Background: While stroke is the second leading cause of death worldwide, little work has been done to quantify the growth and progress of stroke publications. The purpose of this study is to quantitatively analyze trends in the stroke literature over the past 12 years, specifically examining changes in worldwide productivity and study methodology. Methods: The study was a retrospective bibliometric analysis of all stroke articles published between 1996 and 2008 indexed in MEDLINE. Country of origin, MEDLINE-defined methodology, specialty of the first author, and funding sources (for US articles) were recorded. Growth was analyzed by using linear and nonlinear regression. Results: Total articles numbered 32,309 during the study period, with leading global contributors including the United States with 8795 (27.2%) articles, Japan with 2757 (8.5%) articles, and the United Kingdom with 2629 (8.1%) articles. Growth globally and in the United States followed a linear pattern at 209.9 and 56.2 articles per year, respectively (both P < 0.001). Review articles and clinical trials numbered 5932 (18.4%) and 2934 (9.1%), respectively. Clinical trials followed an exponential growth pattern of 7.7% per year (P < 0.001). Regarding specialty influence, pain management and rehabilitation had the largest proportional growth in clinical trials from 4 to 51 articles. Conclusions: Within the stroke literature, we observed continued growth worldwide, sustained growth in the United States, and a steady increase in the number of clinical trials, especially by pain management and rehabilitation.

Background: Type I Arnold-Chiari malformation (ACM) has an adult onset and consists of a downward displacement of the cerebellar tonsils and the medulla through the foramen magnum. There is paucity of literature on the anesthetic management during pregnancy of residual ACM Type I, with cervical xyphosis and persistent syringomyelia. Case Description: A 34-year-old woman with surgically corrected ACM Type I presented for Cesarean delivery. A recent MRI demonstrated worsening of cervical xyphosis after several laminectomies and residual syringomyelia besides syringopleural shunt. Awake fiberoptic intubation was performed under generous topical anesthesia to minimize head and neck movement during endotracheal intubation. We used a multimodal general anesthesia without neuromuscular blockade. The neck was maintained in a neutral position. Following delivery, the patient completely recovered in post-anesthesia care unit (PACU), with no headache and no exacerbation or worsening of neurological function. Conclusions: The present case demonstrates that patients with partially corrected ACM, syringomyelia, cervical kyphosis, and difficult intubation undergoing Cesarean delivery require an interdisciplinary team approach, diligent preparation, and skilled physicians.

Background: Utilization of the transforaminal lumbar interbody fusion (TLIF) approach for scoliosis offers the patients deformity correction and interbody fusion without the additional morbidity associated with more invasive reconstructive techniques. Published reports on complications associated with these surgical procedures are limited. The purpose of this study was to quantify the intra- and postoperative complications associated with the TLIF surgical approach in patients undergoing surgery for spinal stenosis and degenerative scoliosis correction. Methods: This study included patients undergoing TLIF for degenerative scoliosis with neurogenic claudication and painful lumbar degenerative disc disease. The TLIF technique was performed along with posterior pedicle screw instrumentation. The average follow-up time was 30 months (range, 15-47). Results: A total of 29 patients with an average age of 65.9 years (range, 49-83) were evaluated. TLIFs were performed at 2.2 levels on average (range, 1-4) in addition to 6.0 (range, 4-9) levels of posterolateral instrumented fusion. The preoperative mean lumbar lordosis was 37.6° (range, 16°-55°) compared to 40.5° (range, 26°-59.2°) postoperatively. The preoperative mean coronal Cobb angle was 32.3° (range, 15°-55°) compared to 15.4° (range, 1°-49°) postoperatively. The mean operative time was 528 min (range, 276-906), estimated blood loss was 1091.7 mL (range, 150-2500), and hospitalization time was 8.0 days (range, 3-28). A baseline mean Visual Analog Scale (VAS) score of 7.6 (range, 4-10) decreased to 3.6 (range, 0-8) postoperatively. There were a total of 14 (49%) hardware and/or surgical technique related complications, and 8 (28%) patients required additional surgeries. Five (17%) patients developed pseudoarthrosis. The systemic complications (31%) included death (1), cardiopulmonary arrest with resuscitation (1), myocardial infarction (1), pneumonia (5), and pulmonary embolism (1). Conclusion: This study suggests that although the TLIF approach is a feasible and effective method to treat degenerative adult scoliosis, it is associated with a high rate of intra- and postoperative complications and a long recovery process.

Background: Acute neurological deterioration and death in a patient harboring a colloid cyst of the third ventricle remains a poorly understood phenomenon. Sudden neurological derangement caused by spontaneous bleeding within a colloid cyst is a rare and potentially fatal event, usually requiring immediate diagnosis and emergency surgical treatment. Case Description: A 47-year-old male presented with acute right-sided hemiparesis and speech impediment, followed by rapid deterioration of consciousness. Neuroimaging studies showed a rounded mass at the roof of the anterior third ventricle, causing biventricular hydrocephalus along with a left-sided basal ganglia hematoma. The lesion showed scattered foci of a recent hemorrhage which extended into the left lateral ventricle. Surgical treatment involved emergency external ventricular drainage followed by the prompt elective total resection of the lesion via a transcallosal route. Pathological findings confirmed the diagnosis of a colloid cyst with focal areas of vascular congestion and blood extravasation within its wall. Conclusions: Spontaneous bleeding into a colloid cyst of the third ventricle may cause acute obstructive hydrocephalus and intracranial hypertension due to rapid enlargement of the lesion. This event may account for the sudden neurological deterioration and/or death observed in a previously asymptomatic patient. The diagnosis of hemorrhagic phenomena within a colloid cyst represents a challenge due to the variable signal usually displayed by these lesions on computed tomography (CT) and magnetic resonance imaging (MRI). Emergency ventricular drainage followed by elective tumoral removal constitutes a valid and safe treatment strategy.

Background: Duplication of the pituitary gland (DPG) is a rare craniofacial developmental anomaly occurring during blastogenesis with postulated etiology such as incomplete twinning, teratogens, median cleft face syndrome or splitting of the notochord. The complex craniocaudal spectrum of blastogenesis defects associated with DPG is examined with an illustrative case. Case Description: We report for the first time in the medical literature some unique associations with DPG, such as a clival encephalocele, third cerebral peduncle, duplicate odontoid process and a double tongue with independent volitional control. This patient also has the previously reported common associations such as duplicated sella, cleft palate, hypertelorism, callosal agenesis, hypothalamic enlargement, nasopharyngeal teratoma, fenestrated basilar artery and supernumerary teeth. This study also reviews 37 cases of DPG identified through MEDLINE literature search from 1880 to 2011. It provides a detailed analysis of the current case through physical examination and imaging. Conclusion: The authors propose that the developmental deformities associated with duplication of pituitary gland (DPG) occur as part of a developmental continuum, not as chance associations. Considering the fact that DPG is uniquely and certainly present throughout the spectrum of these blastogenesis defects, we suggest the term DPG-plus syndrome.

Background: Osteochondroma is a common bone tumor and rarely affects the central nervous system. Although intraspinal osteochondromas are known to cause neurological deficits, intracranial osteochondromas with neurological compromise are very rare. Case Description: The authors report an exceptional case of a quadriparetic 73-year-old patient with a basioccipital bone osteochondroma growing into the foramen magnum. The embryology, differential diagnoses, and optimal management strategies are discussed. Conclusion: Although extremely rare, osteochondromas should be included in the differential diagnoses of tumors within the foramen magnum. For the tumors originating from the basioccipital bone, a simple medial suboccipital approach might suffice, while for ventral tumors, a far lateral transcondylar approach is necessary to avoid any neurovascular complications. Despite potentially catastrophic presenting symptoms, these tumors are pathologically benign and complete excision often results in long-term cure. To the best of our knowledge, this is the first report of an osteochondroma arising from the basiocciput.

Background: There are limited indications for superficial temporal artery to middle cerebral artery (STA-MCA) bypass in the treatment of cerebral atherosclerotic disease. However, recent reports emphasize that STA-MCA bypass may be beneficial for select patients. In this report, we describe a case in which a flow-dependent STA-MCA bypass was achieved in a patient with unstable internal carotid artery (ICA) stenosis. Case Description: A 51-year-old woman presented with left ICA occlusion. A severely elongated mean transit time (MTT) indicated misery perfusion. STA-MCA bypass was performed immediately and blood flow through the graft appeared excellent on magnetic resonance angiography (MRA). Two weeks later, MRA revealed normal anterograde ICA blood flow and the bypass graft was not visible. Three years later, the left ICA stenosis again became severe and the patient developed contralateral hemiparesis. She underwent endovascular surgery and the ipsilateral MCA became occluded during the procedure. The STA-MCA bypass graft appeared immediately after the MCA occlusion and became a major provider of blood flow to the ipsilateral MCA area. She recovered with almost no deficit. Conclusion: This is a rare case which shows that dynamic flow changes through an STA-MCA bypass can occur with variable ICA blood flow. STA-MCA bypass can be beneficial for the treatment of unstable ICA stenosis.

Our understanding of the pathophysiological and biochemical basis of a number of neurological disorders has increased enormously over the last three decades. Parallel with this growth of knowledge has been a clearer understanding of the mechanism by which a number of naturally occurring plant extracts, as well as whole plants, can affect these mechanisms so as to offer protection against injury and promote healing of neurological tissues. Curcumin, quercetin, green tea catechins, balcalein, and luteolin have been extensively studied, and they demonstrate important effects on cell signaling that go far beyond their antioxidant effects. Of particular interest is the effect of these compounds on immunoexcitotoxicity, which, the authors suggest, is a common mechanism in a number of neurological disorders. By suppressing or affecting microglial activation states as well as the excitotoxic cascade and inflammatory mediators, these compounds dramatically affect the pathophysiology of central nervous system disorders and promote the release and generation of neurotrophic factors essential for central nervous system healing. We discuss the various aspects of these processes and suggest future directions for study.

Background: Because extra-axial cavernous malformations (CMs) are rare, the common clinical course remains unclear. We report the case of a patient with progressive CM originating from the cerebellar tentorium. Case Description: A 64-year-old woman was admitted to our hospital with the complaint of diplopia. Magnetic resonance (MR) imaging revealed a lesion attached to the left cerebellar tentorium, close to the cerebral peduncle. This well-demarcated lesion rapidly enlarged for 3 months and eroded into the midbrain. Cerebral angiography showed a branch of the middle meningeal artery supplying the lesion and pooling of the contrast medium in the venous phase. A dark reddish and mulberry-like mass of the tentorium was observed intraoperatively, allowing the diagnosis of a tentorial CM. The feeding artery was identified in the tentorium and was coagulated. Postoperative MR imaging showed remarkable mass reduction and central necrosis of the lesion. However, the lesion recurred in 3 months; consequently, gamma knife radiosurgery was performed. After an additional 2 months, the lesion shrank in response to the radiosurgery. Conclusions: We report an extremely rare case of tentorial CM which showed rapid growth in a short period. Coagulation of the feeding artery was not sufficient to control the lesion. Gamma knife radiosurgery may prove highly effective for recurrent lesions.

Background: Cerebellopontine angle (CPA) lesions can mimic more common tumors through nonspecific symptoms and radiologic findings. Methods: To increase the preoperative diagnostic accuracy for CPA pathologies, the authors review the full spectrum of reported CPA lesions. Results: A wide spectrum of lesions mimics vestibular schwannoma (VS) in the space of the CPA. Conclusion: The presence of any suspicious clinical and radiographic finding uncharacteristic of VS makes it necessary to maintain a broad differential diagnosis list. Differentiation of CPA lesions, although challenging, may be best achieved by incorporating the clinical history, physical exam findings, audiometry results, and multi-modality imaging studies to construct a comprehensive preoperative knowledge of the lesion. This knowledge will allow improved operative execution and outcomes.

Background: There has been a tremendous amount of interest focused on the topic of concussions over the past few decades. Neurosurgeons are frequently consulted to manage patients with mild traumatic brain injuries (mTBI) that have radiographic evidence of cerebral injury. These injuries share significant overlap with concussions, injuries that typically do not reveal radiographic evidence of structural injury, in the realms of epidemiology, pathophysiology, outcomes, and management. Further, neurosurgeons often manage patients with extracranial injuries that have concomitant concussions. In these cases, neurosurgeons are often the only "concussion experts" that patients encounter. Results: The literature has been reviewed and data have been synthesized on the topic including sections on historical background, epidemiology, pathophysiology, diagnostic advances, clinical sequelae, and treatment suggestions, with neurosurgeons as the intended target audience. Conclusions: Neurosurgeons should have a fundamental knowledge of the scientific evidence that has developed regarding concussions and be prepared to guide patients with treatment plans.

Background: Dissecting through the gluteus maximus muscle by splitting its fibers, instead of complete sectioning of the muscle, is faster, involves less damage to tissues, and diminishes recovery time. The objective of the current paper is to present a clinical series of sciatic nerve lesions where the nerve was sufficiently exposed via the transgluteal approach. Methods: We retrospectively selected 18 traumatic sciatic nerve lesions within the buttock, operated upon from January 2005 to December 2009, with a minimum follow-up of 2 years. In all patients, a transgluteal approach was employed to explore and reconstruct the nerve. Results: Ten males and eight females, with a mean age of 39.7 years, were studied. The etiology of the nerve lesion was previous hip surgery (n = 7), stab wound (n = 4), gunshot wound (n = 3), injection (n = 3), and hip dislocation (n = 1). In 15 (83.3%) cases, a motor deficit was present; in 12 (66.6%) cases neuropathic pain and in 12 (66.6%) cases sensory alterations were present. In all cases, the transgluteal approach was adequate to expose the injury and treat it by neurolysis alone (10 cases), neurolysis and neurorrhaphy (4 cases), and reconstruction with grafts (4 cases; three of these paired with neurolysis). The mean pre- and postoperative grades for the tibial nerve (LSUHSC scale) were 1.6 and 3.6, respectively; meanwhile, for the peroneal division, preoperative grade was 1.2 and postoperative grade was 2.4. Conclusions: The transgluteal approach adequately exposes sciatic nerve injuries of traumatic origin in the buttock and allows for adequate nerve reconstruction without sectioning the gluteus maximus muscle.

Background: The influence of cerebral perfusion pressure (CPP) on real-time focal cerebral blood flow (fCBF) is not fully understood, in either intact or injured brain. We wanted to evaluate that relationship, and by implication investigate the relative importance of perfusion pressure versus metabolism in the regulation and control of cerebral blood flow. Our hypothesis was that metabolic needs dominated over a physiologic range of blood pressure. Methods: This was an observational study of 23 patients, most of them with closed head injury, three with subarachnoid hemorrhage, one with a gunshot wound to the brain, and one monitored after craniotomy for unruptured aneurysm. Arterial lines, ventriculostomies, and fCBF monitors were placed. CPP (mean arterial pressure − intracranial pressure) and fCBF were measured and recorded to a computer database every minute. The relationship between CPP and fCBF was graphed and correlation coefficients were compared between survivors and non-survivors. Results: Graphs of CPP versus fCBF did not show any linearity over a range of 50-150 mm Hg in patients who survived. In those who died, four of seven showed some indication of linearity. The difference in the correlation coefficients between survivors and non-survivors was statistically significant (P < 0.05), with survivors having essentially no correlation, as expected with autoregulation intact, and non-survivors having a mean correlation of 0.311. Conclusions: In the functioning and viable brain, metabolic regulation of cerebral blood flow (CBF) predominates, leading to the lack of an obvious relationship between perfusion pressure and flow. This predominance of metabolic regulation is robust and preserved over a wide range of brain injury, with pressure autoregulation necessary but not clinically apparent in the metabolically active brain. This robust and constantly varying relationship of pressure and flow shown by our real-time measurements of fCBF has important implications for interpreting clinical measurements of autoregulation. Perhaps most importantly, the development of a correlation between pressure and flow may indicate and be an early warning of deterioration.

Background: Decompressive craniectomy is undertaken for relief of brain herniation caused by acute brain swelling. Brain stiffness can be estimated by palpating the decompressive cranial defect and can provide some relatively subjective information to the neurosurgeon to help guide care. The goal of the present study was to objectively evaluate transcutaneous stiffness of the cranial defect using a tactile resonance sensor and to describe the values in patients with a decompressive window in order to characterize the clinical association between brain edema and stiffness. Methods: Data were prospectively collected from 13 of 37 patients who underwent a decompressive craniectomy in our hospital during a 5-year period. Transcutaneous stiffness was measured as change in frequency and as elastic modulus. Results: Stiffness variables of the decompressive site were measured without any adverse effect and subsequent calculations revealed change in frequency = 101.71 ± 36.42 Hz, and shear elastic modulus = 1.99 ± 1.11 kPa. Conclusions: The elasticity of stiffness of a decompressive site correlated with brain edema, cisternal cerebrospinal fluid pressure, and brain shift, all of which are related to acute brain edema.

Background: Congenital intracranial dermoid tumors are very rare. The location of these dermoid lesions in the cavernous sinus and the complexity of the operative procedure for these lesions have been noted by several authors. Dermoid tumors originating in the cavernous sinus are usually interdural, and thus blurred vision is an uncommon presentation. Case Description: Herein we report the first incidental case of a cavernous sinus dermoid cyst in a 21-year-old woman. Conclusions: A literature review was done and the possible treatments and approaches for this lesion are discussed. We consider that surgical treatment is indicated in most incidental cavernous sinus dermoid lesions due to the possible symptoms related to compression or rupture leading to chemical meningitis.

Background: The authors report a case of intraparenchymal germinoma pathologically diagnosed using navigation-guided endoscopic biopsy. Case Description: A 27-year-old man had mild left hemiparesis, transcortical motor aphasia, and amnesia. Magnetic resonance (MR) imaging revealed an intraparenchymal mass lesion near the left ventricular trigone. Navigation-guided endoscopic biopsy was performed, and histopathology revealed large neoplastic cells immunohistochemically positive for germinoma-specific antigens, which were diagnosed as pure germinoma. Chemotherapy with whole-brain radiotherapy was performed, and the neurological symptoms did not change during the treatment. Follow-up MR imaging 1 year after the surgery showed no evidence of recurrence or dissemination. Conclusions: Navigation-guided endoscopic biopsy can be a useful technique in such intraparenchymal germinoma cases.

Background: Interspinous fusion devices (IFDs) are increasingly offered to patients over the age of 50 with lumbar spinal stenosis and intermittent neurogenic claudication. Here, we review the literature on complication rates, reoperation rates, and outcomes for implanting IFD, and offer an assessment of IFD charges at a single institution in 2010. Methods: The literature concerning IFD implants was reviewed with particular attention focused on complications, reoperation rates, and outcomes. Additionally, the costs of implanting 31 IFD devices in 16 patients at one to three levels at a single institution in 2010 are presented. Results: Reviewing the spinal literature concerning the postoperative status of IFD followed over an average of 23-42.9 postoperative months revealed that IFD resulted in 11.6-38% complication rate, 4.6-85% reoperation rate, and 66.7-77% frequency of poor outcomes. Additionally, the 31 devices implanted in 16 patients at a single university hospital in 2010 cost a total of $576,407. Conclusions: With high maximal complication rates (38%), reoperation rates (85%), poor outcomes (77%), and high costs ($576,407 for 31 devices in 16 patients), the utilization and implantation of IFD remains extremely controversial and should be investigated further.

Background: Spinal hemangioblastomas (HB) are rare, histologically benign, highly vascularized tumors often associated with von Hippel-Lindau (VHL) disease. The aim of the current study is to demonstrate the benefit of early surgical resection of large spinal HBs in selected asymptomatic patients with VHL. Methods: Seventeen patients underwent microsurgical resection of 20 spinal HBs at the Department of Neurosurgery at Helsinki University Central Hospital (HUCH). Thirteen tumors were in the cervical spine, five in thoracic and one patient had two lumbar lesions. MRI tumor showed an associated syrinx in 16 patients (94%). Tumor volume ranged from 27 to 2730 mm³ . Out of 17 patients, 11 (65%) tested positive for VHL in mutation analysis. Five of these patients with tumors ranging from 55 to 720 mm³ were treated prophylactically. Results: Complete tumor resection was performed in 16 patients (94%) who were followed up for a median of 57 months (range 2-165 months). No patient had neurological decline on long-term follow-up. Among the patients with VHL, five patients with preoperative sensorimotor deficits showed improvement of their symptoms but never regained full function. One patient who presented with tetraplegia remained the same. Otherwise, all five patients with prophylactic surgery remained neurologically intact. Conclusion: Although documented growth on serial MRIs and the need for pathological diagnosis have been suggested as indications for surgery in otherwise asymptomatic patients, our series showed that a potentially larger group of asymptomatic patients with spinal HB associated with VHL would benefit from microsurgical resection. Long-term results of the surgical management of spinal HB are generally favorable. Our results suggest staging and early treatment for spinal HB larger than 55 mm³ , especially in patients with VHL. Small spinal HBs may be followed up.

Background: Endovascular embolization represents the method of choice for the treatment of carotid-cavernous fistulas (CCFs). Methods: We report our experience using the endovascular technique in 24 patients harboring 25 CCFs treated between October 1994 and April 2010, with an emphasis on the role of detachable balloons for the treatment of direct CCFs. Results: Of the 16 patients who presented with direct CCFs (Barrow Type A CCFs) (age range, 7-62 years; mean age, 34.3 years), 14 were caused by traumatic injury and 2 by a ruptured internal carotid artery (ICA) aneurysm. Eight patients (age range, 32-71 years; mean age, 46.5 years) presented with nine indirect CCFs (Barrow Types B, C, and D). The clinical follow-up after endovascular treatment ranged from 2 to 108 months (mean, 35.2 months). In two cases (8%), the endovascular approach failed. Symptomatic complications related to the procedure occurred in three patients (12.5%): transient cranial nerve palsy in two patients and a permanent neurological deficit in one patient. Detachable balloons were used in 13 out of 16 (81.3%) direct CCFs and were associated with a cure rate of 92.3%. Overall, the angiographic cure rate was obtained in 22 out of 25 (88%) fistulas. Patients presenting with III nerve palsy improved gradually between 1 day and 6 months after treatment. Good clinical outcomes [modified Rankin scale (mRS) ≤ 2] were observed in 22 out of 24 (91.6%) patients at last follow-up. Conclusions: Endovascular treatment using detachable balloons still constitutes a safe and effective method to treat direct carotid-cavernous fistulas.

Objective: Leber congenital amaurosis (LCA) is a rare, clinically and genetically heterogeneous disorder characterized by severe loss of vision in the first year of life, affecting approximately 3000 people in the United States. Some LCA patients manifest developmental abnormalities of the central nervous system (CNS) and neuroradiological studies have revealed a variety of cerebral anomalies in association with LCA; however, Chiari I malformations (CMI) have never been described. Case Description: We report two sisters who were referred to the pediatric neurosurgery clinic for evaluation of CMI. The elder sister presented with convergence nystagmus from 3 months of age and magnetic resonance imaging (MRI) demonstrated evidence of significant CMI. Her younger sister began developing nystagmus at 4 months of age. Both had symptomatic progression and underwent suboccipital decompression. Both were subsequently diagnosed with LCA. Case specifics and imaging findings are presented. Conclusions: CMI have been found in association with several genetic syndromes, but not with LCA. These patients represent the first reported cases of CMI with LCA and suggest an additional potential CNS anomaly. The unique occurrence in siblings and the association with another inherited disorder are suggestive of a genetic basis for CMI.

Objective: Cerebral vasospasm is the commonest cause for mortality and morbidity in patients following clipping of a ruptured aneurysm. Selective phosphodiesterase (PDE) inhibitor like sildenafil acts as a vasodilator. The objective of this study was to evaluate the safety and feasibility of oral sildenafil citrate in patients with symptomatic refractory vasospasm. Methods: A total of 832 patients with aneurysmal subarachnoid bleed were operated in 4 years. Two hundred and seventy-three patients had vasospasm. Of these, 72 patients had refractory cerebral vasospasm. Vasospasm was defined as "refractory" when institution of "HHH" failed to reverse the transcranial Doppler (TCD) values even after 24 hours. Computed tomography (CT) scan showed no infarct, hematoma, or hydrocephalus, and the serum electrolytes were within normal limits. They received 100-150 mg of sildenafil every 4 hours. Response was evaluated by 2-hourly TCD. Results: Eight patients had sustained (TCD values normal for >48 hours) and four had temporary relief in vasospasm, as suggested. Four patients developed complications significant enough to terminate the therapy. Conclusions: Sildenafil citrate may be effective in patients with refractory symptomatic vasospasm. It calls upon the pharmacologists and scientists to discover newer supraselective PDE inhibitors, specific to PDE receptors in brain vessels.

In the fall of 1999, the Institute of Medicine released "To Err is Human: Building a Safer Health System," a sobering report on the safety of the American healthcare industry. This work and others like it have ushered in an era where the science of quality assurance has quickly become an integral facet of the practice of medicine. One critical component of this new era is the development, application, and refinement of checklists. In a few short years, the checklist has evolved from being perceived as an assault on the practitioners' integrity to being welcomed as an important tool in reducing complications and preventing medical errors. In an effort to further expand the neurosurgical community's acceptance of surgical checklists, we review the rationale behind checklists, discuss the history of medical and surgical checklists, and remark upon the future of checklists within our field.

Background: Rosai-Dorfman disease (RDD) was first described in 1969 as an idiopathic histiocytic proliferative disorder. It commonly presents as a massive and painless adenopathy. Until 1990, extranodal involvement of the central nervous system (CNS) was rare and reported in less than 5% of the total number of patients with extranodal RDD. Complete removal of CNS RDD has been achieved in many cases. Case Description: We report a case of an isolated intracranial RDD in a 53-year-old man. The patient had an episode of generalized seizures. Imaging studies of the brain were compatible with a meningioma en plaque. The mass was exposed by a right frontotemporal craniotomy. The tumor was adhered tightly to the adjacent cerebral cortex and was permeated by pial arteries of the brain surface. The sacrificing of these arteries was inevitable in order to achieve the total removal of the tumor. The patient had incomplete left hemiparesis after the surgery. Brain computed tomography (CT) imaging revealed a postoperative hemorrhage and a low-density lesion in the right frontal lobe. The patient was postoperatively diagnosed with isolated central nervous system RDD. Conclusion: Although the complete removal of dural-based lesions without any neurological deficits has been performed in many cases, the treatment of cases with high risks, such as the present case, indicates conservative excisions and adjuvant radiotherapy with or without chemotherapy.

Precision is the ultimate aim of stereotactic technique. Demands on stereotactic precision reach a pinnacle in stereotactic functional neurosurgery. Pitfalls are best avoided by possessing in-depth knowledge of the techniques employed and the equipment used. The engineering principles of arc-centered stereotactic frames maximize surgical precision at the target, irrespective of the surgical trajectory, and provide the greatest degree of surgical precision in current clinical practice. Stereotactic magnetic resonance imaging (MRI) provides a method of visualizing intracranial structures and fiducial markers on the same image without introducing significant errors during an image fusion process. Although image distortion may potentially limit the utility of stereotactic MRI, near-complete distortion correction can be reliably achieved with modern machines. Precision is dependent on minimizing errors at every step of the stereotactic procedure. These steps are considered in turn and include frame application, image acquisition, image manipulation, surgical planning of target and trajectory, patient positioning and the surgical procedure itself. Audit is essential to monitor and improve performance in clinical practice. The level of stereotactic precision is best analyzed by routine postoperative stereotactic MRI. This allows the stereotactic and anatomical location of the intervention to be compared with the anatomy and coordinates of the intended target, avoiding significant image fusion errors.

Vagus nerve stimulation (VNS) is a unique epilepsy treatment in that a peripheral intervention is used to treat a disease that is entirely related to pathological events occurring within the brain. To understand how stimulation of the vagus nerve can be used to stop seizures, an understanding of the peripheral anatomy and physiology of the vagus nerve is essential. The peripheral aspects of the vagus nerve are discussed in this review, with an explanation of which fibers and branches are involved in producing these antiepileptic effects, along with speculation about the potential for improving the therapy.

The amygdala was a popular target during the era of psychosurgery, specifically for the treatment of intractable aggression. This mesiotemporal structure was thought to primarily mediate fear and anger. However, recent evidence suggests that the amygdala is part of a complex network that mediates the formation of a larger repertoire of positive and negative emotions. Dysfunctions within the network or the amygdala itself can lead to various mental illnesses. In those cases, deep brain stimulation (DBS) applied focally may treat the symptoms. This review presents data supporting the potential therapeutic role of DBS of the amygdala in the treatment of anxiety disorders, addiction, and mood disorders. The success of DBS for psychiatric conditions will likely depend on our ability to precisely determine the optimal target for a specific case.

Background: Behavioral surgery (BS) is resurging because of unmet clinical need, advances in basic sciences, neuroimaging, neurostimulation, and stereotaxy. However, there is a danger that BS will fall unless acceptable strategies are adopted by BS providers. Methods: A critical review of conditions leading to rise of psychosurgery (PS) and concerns resulting in its fall was conducted to learn lessons and safeguard BS of the future. Results: PS rose and spread in 1960 like wildfire without adequate preclinical and clinical studies. Hundreds of patients had PS without adequate preoperative diagnosis or assessment, proper consent, and non-objective reporting of outcome. Furthermore, there was public opposition against PS because of its potential abuse to control violent behavior and dissidents. Advances in neurostimulation, neuroimaging, and stereotaxy, and emergence of treatment-resistant mental disorders led to increased interest in BS. Several recent studies have shown BS to be safe and effective. However, concerns related to strength of evidence, safety, efficacy, consent, and objectivity of studies have been raised. Unless clinical and regulatory governance structures are adopted in each jurisdiction, BS will face the same fate as that of PS in the past. Conclusion: The future of BS as a safe and effective therapy is dependent upon adopting clear moral ethical and governance standards on the following lines: Patients must have failed adequate therapies; must be assessed by psychiatrist-led multidisciplinary teams; patients' abilities to give consent and diagnosis must be verified by independent authorities designated for this purpose by the state; and the independent authority must also decide whether the teams were adequately trained to perform BS.

The success of deep brain stimulation (DBS) surgery in treating medically refractory symptoms of some movement disorders has inspired further investigation into a wide variety of other treatment-resistant conditions. These range from disorders of gait, mood, and memory to problems as diverse as obesity, consciousness, and addiction. We review the emerging indications, rationale, and outcomes for some of the most promising new applications of DBS in the treatment of postural instability associated with Parkinson's disease, depression, obsessive-compulsive disorder, obesity, substance abuse, epilepsy, Alzheimer's-type dementia, and traumatic brain injury. These studies reveal some of the excitement in a field at the edge of a rapidly expanding frontier. Much work still remains to be done on basic mechanism of DBS, optimal target and patient selection, and long-term durability of this technology in treating new indications.

Classical trigeminal neuralgia is a chronic pain condition that was clinically recognized centuries ago. Nevertheless, the pathological mechanism(s) involved in the development of classical trigeminal neuralgia is still largely based on the theory of peripheral versus central nervous system origin. Limitations of both hypotheses are discussed. Evidence of radiation effects in the electrical conduction of peripheral nerves is reviewed. Results of experimental studies using modern and current radiosurgery techniques and doses are also brought to discussion in an attempt to elucidate the radiation mechanisms involved in the conduction block of excessive sensory information triggering pain attacks. Clinical features and prognostic factors associated with pain control, recurrence, and facial numbness in patients submitted to surgical procedures for classical trigeminal neuralgia are discussed in the context of the features related to the pathogenesis of this condition. Studies focusing on the electrophysiology properties of partially demyelinated trigeminal nerves submitted to radiosurgery are vital to truly advance our current knowledge in the field.

Initially designed for the treatment of functional brain targets, stereotactic radiosurgery (SRS) has achieved an important role in the management of a wide range of neurosurgical pathologies. The interest in the application of the technique for the treatment of pain, and psychiatric and movement disorders has returned in the beginning of the 1990s, stimulated by the advances in neuroimaging, computerized dosimetry, treatment planning software systems, and the outstanding results of radiosurgery in other brain diseases. Since SRS is a neuroimaging-guided procedure, without the possibility of neurophysiological confirmation of the target, deep brain stimulation (DBS) and radiofrequency procedures are considered the best treatment options for movement-related disorders. Therefore, SRS is an option for patients who are not suitable for an open neurosurgical procedure. SRS thalamotomy provided results in tremor control, comparable to radiofrequency and DBS. The occurrence of unpredictable larger lesions than expected with permanent neurological deficits is a limitation of the procedure. Improvements in SRS technique with dose reduction, use of a single isocenter, and smaller collimators were made to reduce the incidence of this serious complication. Pallidotomies performed with radiosurgery did not achieve the same good results. Even though the development of DBS has supplanted lesioning as the first alternative in movement disorder surgery; SRS might still be the only treatment option for selected patients.

Functional neurosurgery includes surgery conducted to ablate, augment, or modulate targets that lead to improvement in neurological function or behavior. Surgical approaches for this purpose include destructive lesioning with different mechanical or biologic agents or energy sources, non-destructive electrical modulation, and cellular or chemical augmentation. Our purpose was to review the role of stereotactic radiosurgery used for functional indications and to discuss future applications and potential techniques. Imaging and neurophysiological research will enable surgeons to consider new targets and circuits that may be clinically important. Radiosurgery is one minimal access approach to those targets.

Background: Although the frequency of spinal surgical procedures has been increasing, particularly in patients of age 65 and over (geriatric), multiple overlapping comorbidities increase their risk/complication rates. Nevertheless, sometimes these high-risk geriatric patients are considered for "unnecessary", too much (instrumented fusions), or too little [minimally invasive surgery (MIS)] spine surgery. Methods: In a review of the literature and reanalysis of data from prior studies, attention was focused on the increasing number of operations offered to geriatric patients, their increased comorbidities, and the offers for "unnecessary" spine fusions, including both major open and MIS procedures. Results: In the literature, the frequency of spine operations, particularly instrumented fusions, has markedly increased in patients of age 65 and older. Specifically, in a 2010 report, a 28-fold increase in anterior discectomy and fusion was observed for geriatric patients. Geriatric patients with more comorbid factors, including diabetes, hypertension, coronary artery disease (prior procedures), depression, and obesity, experience higher postoperative complication rates and costs. Sometimes "unnecessary," too much (instrumented fusions), and too little (MIS spine) surgeries were offered to geriatric patients, which increased the morbidity. One study observed a 10% complication rate for decompression alone (average age 76.4), a 40% complication rate for decompression/limited fusion (average age 70.4), and a 56% complication rate for full curve fusions (average age 62.5). Conclusions: Increasingly, spine operations in geriatric patients with multiple comorbidities are sometimes "unnecessary," offer too much surgery (instrumentation), or too little surgery (MIS).

Background: Vestibular schwannomas are benign brain tumors arising from the 8th cranial nerve with a varying natural history. Various reports have described discernable growth patterns for these tumors. However, growth predictability remains low because of slow and indeterminate changes over time with follow-up reports not usually exceeding 3 years. Our report describes the long-term follow-up of an unusual cystic schwannoma with growth patterns prior to and following treatment, adding valuable information to the variable natural history and outcome of these infrequent tumors. Case Description: A 68-year-old gentleman presented with a left-sided cystic vestibular schwannoma, initially managed conservatively. Imaging revealed wide variations in the size of his tumor over a period of 3 years. He was finally treated with Gamma Knife radiosurgery, and at 1 year following treatment shows tumor shrinkage with a change in tumor morphology. Conclusion: To our knowledge, the present case represents the first instance of a schwannoma showing wide fluctuations in tumor size and morphology over a period of time, with a good response to radiosurgery. We emphasize in this report that there is no "one size fits all" treatment paradigm for these tumors and each patient requires individualized care and intervention, taking into account their differing natural histories.

Background: Purely extradural lumbar schwannomas are rare lesions. Resection traditionally requires an open laminectomy and ipsilateral complete facectomy. Recent reports have demonstrated safety and efficacy of removal of these tumors using mini-open access devices with expandable retractors. We report a case of a giant L3 schwannoma successfully resected through a minimally invasive approach using the non-expandable Spotlight tubular retrator (Depuy Spine). Case Description: A 77-year-old woman presented with a history of chronic right leg pain, paresthesias and proximal right leg weakness. Magnetic Resonance imaging (MRI) scan revealed a large dumbbell-shaped extradural foraminal lesion at the L3-L4 level with significant extraforaminal extension. The patient underwent a minimally invasive gross total resection (GTR) of the tumor using an 18-mm Spotlight tubular retractor system. Pathology confirmed the lesion to be a benign schwannoma. Postoperatively, the patient's symptoms resolved and she was discharged from the hospital on the second postoperative day. Postoperative MRI showed no residual tumor. The patient returned to normal activities after 2 weeks and remained asymptomatic with no neurological deficits at final 6 months follow-up. Conclusion: Giant lumbar extradural schwannomas can be safely and completely resected using minimally invasive surgery without the need for facectomy or subsequent spinal fusion.

Background: Significant controversy exists regarding the existence of the so-called arcade of Struthers and whether this structure is involved in some cases of proximal ulnar nerve entrapment. Therefore, the aim of the present study was to further elucidate this anatomy. Methods: Fifteen cadavers (30 sides) underwent dissection of the medial arm with special attention to the course of the ulnar nerve and its relationships to the soft tissues of this region. Results: We identified a thickening in the inferior medial arm that crosses the ulnar nerve and is consistent with the so-called arcade of Struthers in 86.7% of sides. On 57.7% of the sides, the arcade was found to be due to a thickening of the brachial fascia and was classified as a type I arcade. On 19.2% of the sides, the arcade was due to the internal brachial ligament and these were classified as type II arcades. On 23.1% of the sides, the arcade was due to a thickened medial intermuscular septum and these were classified as type III arcades. The mean length of the arcade was 4.3 cm and the distal end of the arcade was, on average, 6.8 cm above the medial epicondyle. Although the presence of an arcade of Struthers was slightly more common in female specimens, this did not reach statistical significance. However, arcades were found more often on right side (P < 0.001). Conclusions: Based on our findings, the arcade of Struthers is an anatomical band of connective tissue in the medial distal arm that crosses the ulnar nerve. This structure was found in the majority of our specimens and may need to be evaluated in proximal ulnar neuropathies. We believe that past studies that have not observed the arcade and past studies with varied findings are due to the various definitions used for this anatomical structure. Using the classification system as demonstrated in the present study may make future communications regarding the arcade of Struthers more exact.

Objective: To observe interdepartmental variation in the availability of resources and academic activities within the various neurosurgery programs of Pakistan. Methods: This was a proforma-based survey of neurosurgery trainees and young neurosurgeons of Pakistan, looking at the academic infrastructure and output of their programs. The proforma was filled by 36 respondents from 11 neurosurgery centers of the country. All these centers were accredited for neurosurgery training in Pakistan. Results: Out of the 36 respondents, 30 were completing a Fellowship training (FCPS) and six were enrolled for a Master in Surgery (MS) program. About 80% of the participants used the Youman's Textbook of Neurosurgery as a reference book. Only 40% of the candidates had access to more than one indexed neurosurgery journal. Structured academic sessions (e.g., journal clubs and neuropathology meetings) were lacking in a majority of the training institutes, 95% of the trainees had no microsurgical laboratory experience, and modern neurosurgical tools (frameless neuronavigation system, neuroendoscopy) were in use at a few centers only. Conclusion: Neurosurgery training in Pakistan is not uniform and wide variations exist between the programs at the centers evaluated. We recommend exchange programs between centers at national and international levels, to allow trainees to gain first-hand exposure to training components not available in their own center.

Background: The choice of radiological investigations in head trauma in Africa is influenced by factors such as cost. Some patients who require computed tomography (CT) scan elsewhere are either managed blindly or do not present for it at the appropriate time. This paper evaluates the CT scan findings as they are obtained in cases of head trauma in a region of Nigeria. Methods: Prospectively recorded data of all head injury patients who presented for CT scan between January 2009 and April 2010 at Memfys Hospital for Neurosurgery (MHN), Enugu, Nigeria, were analyzed. Mobile CereTom 8-Slice CT was used in all cases. New and follow-up cases were included. Results: There were 204 CT scans for head trauma (171 new, 33 follow-up), accounting for about 34% of all head CT scans performed with this unit. The male to female ratio was 3.5:1. About 33.9% of the patients were in the third and fourth decades of life. In 19.9% cases, CT was unremarkable, while 80.1% cases had abnormal CT findings. The CT diagnosis was not in keeping with the indication of head trauma in 7%, and 13% had more than one finding. The most common CT findings were: subdural hematoma 30%, cerebral contusions and edema 30.7%, skull fractures 23.4% and extradural hematoma 8.0%. About 64% of the CT findings required surgical interventions. The overall mortality was 11.1%, but amongst the 137 patients who had abnormal CT findings, it was 13.9%. Conclusion: The high yield and diversity of CT scan findings in head trauma patients support the indication for the appropriate use of CT in diagnosis and management of head trauma even in developing countries.

Background: Simultaneous presentation of multiple primary central nervous system (CNS) malignancies is extremely rare. There have been only eight cases of meningiomas co-existing with primary cerebral lymphoma, reported in the literature. Case Description: We present a case of a patient who underwent surgical resection of an olfactory grove meningioma that was interdigitated with a primary CNS B-cell lymphoma. Following surgery, the patient was treated with high-dose methotrexate, and has no evidence of recurrence after 18 months. Conclusion: Because of the early recognition of these two distinct pathologies, the patient received directed adjuvant therapies, and has exceeded the survival of all other cases reported in the literature.

Background: The technique of sub-pial resection, first described in the early 1900s, was later refined by Penfield and Jasper for removal of supratentorial epileptic cortex. This technique has not been widely adopted for intrinsic tumor resection, for which the most widely used technique involves piecemeal aspiration of the tumor. This technique of "staying within the tumor" results in persistent bleeding, with obscuration of the tumor/brain interface, potentially yielding less than satisfactory results. In our experience, the sub-pial technique is useful for resections of supratentorial intrinsic tumor. We report the use of sub-pial resection technique and present illustrative cases. Methods: The sub-pial resection technique is described along with important clinical decision-making guidelines. Representative cases are presented to discuss application of the sub-pial technique and to demonstrate surgical results. Results: The sub-pial technique preserves the pia during cortical resections and makes it easier to protect and identify normal anatomy, including sulci, gyri, cranial nerves, and major vascular structures. This reduces bleeding, making surgery safer and more efficient. In most cases, an en bloc resection can be accomplished, permitting more accurate histopathology and more extensive tissue acquisition for research purposes. Conclusion: The sub-pial technique can be incorporated into strategies for supratentorial intrinsic tumor resections, including temporal, frontal, occipital, and insular tumors, at para-Sylvian or para-insular-sulcus locations.

Background: Neurosurgical intervention involving the scalp may cause neuralgia or other pain syndromes. Therefore, a comprehensive understanding of scalp innervation may be helpful in prevention of pain potentially induced by surgery. Methods: Using standard search engines, a review of the literature regarding the anatomy of the nerves that innervate the scalp was performed with attention given to anatomic landmarks. Results: This paper provides a comprehensive review of the anatomy, embryology, pathology, and neurosurgical application of the knowledge of the innervation of the scalp. Conclusions: Knowledge of the nerves that supply the scalp is important to the neurosurgeon who hopes to maximize patient recovery and minimize post-procedural complications.

Background: Neurocysticercosis is the most common parasitic infestation of the central nervous system and an important cause of acquired epilepsy. Although endemic in developing countries, with an increased immigration from the endemic regions, it is also seen progressively in other parts of the world. Hence, there is an increased need for awareness of neurocysticercosis in the non-endemic areas. Case Description: The case described here is of a 13-year-old girl who presented with refractory seizures. She had been on antiepileptic medication and had also received anti-parasitic treatment for neurocysticercosis. Surgical intervention was recommended because the seizures were resistant to treatment and also because the diagnosis could not be clearly established. Following surgery, the seizures have been under control and the patient has been doing well. Conclusion: Neurocysticercosis can be a potential cause of refractory seizure even in non-endemic countries. Some cases may be difficult to diagnose. Clinical presentation of seizure and brain imaging should be given priority over blood investigations for diagnosing neurocysticercosis and advanced neurosurgical intervention can be considered in suitable cases for better outcome.

Background: The incidence of primary brain tumors by subtype is currently unknown in Australia. We report an analysis of incidence by tumor subtype in a retrospective multicenter study in the state of New South Wales (NSW) and the Australian Capital Territory (ACT), with a combined population of >7 million with >97% retention rate for medical care. Methods: Data from histologically confirmed primary brain tumors diagnosed from January 2000 through December 2008 were weighted for patient outflow and data completeness, and age standardized and analyzed using joinpoint analysis. Results: A significant increasing incidence in glioblastoma multiforme (GBM) was observed in the study period (annual percentage change [APC], 2.5; 95% confidence interval [CI], 0.4-4.6, n = 2275), particularly after 2006. In GBM patients in the ≥65-year group, a significantly increasing incidence for men and women combined (APC, 3.0; 95% CI, 0.5-5.6) and men only (APC, 2.9; 95% CI, 0.1-5.8) was seen. Rising trends in incidence were also seen for meningioma in the total male population (APC, 5.3; 95% CI, 2.6-8.1, n = 515) and males aged 20-64 years (APC, 6.3; 95% CI, 3.8-8.8). Significantly decreasing incidence trends were observed for Schwannoma for the total study population (APC, −3.5; 95% CI, −7.2 to −0.2, n = 492), significant in women (APC, −5.3; 95% CI, −9.9 to −0.5) but not men. Conclusion: This collection is the most contemporary data on primary brain tumor incidence in Australia. Our registries may observe an increase in malignant tumors in the next few years that they are not detecting now due to late ascertainment. We recommend a direct, uniform, and centralized approach to monitoring primary brain tumor incidence by subtype, including the introduction of nonmalignant data collection.

Background: Angiography-confirmed complete resection of an arteriovenous malformation (AVM) has traditionally been considered curative. However, recurrence of AVM following angiographically proven complete resection does exist, especially in children. This rare occurrence has been reported 29 times in the English language literature. Although recurrence may be asymptomatic, many reported cases result in epilepsy or intracranial hemorrhage anywhere from 0.5 to 9 years following complete resection. We report a rare case of AVM recurrence that became symptomatic 16 years after complete resection. We review the literature and discuss the relevance of performing follow-up imaging to detect AVM recurrence. Case Description: An 8-year-old girl presented with a right occipital hemorrhage with intraventricular extension from a ruptured AVM of the right occipital lobe. She underwent AVM resection through a right occipital craniotomy. Postoperative angiography confirmed complete resection and she made an uneventful recovery. Sixteen years later, she presented with a 2-month history of headaches, nausea and dizziness. Angiography revealed recurrence of the AVM which was completely resected, as documented on postoperative angiography. Conclusion: In children, an AVM may recur after angiography-proven complete resection. Recurrence may be due to persistence and growth of an initially angiographically occult arteriovenous shunt left in place during surgery or the development of a new AVM. In addition to obtaining follow-up angiography 6-12 months after surgery, a late angiography 5 years after resection may be warranted in patients at risk for recurrence. Asymptomatic recurrence detection allows treatment and may prevent the morbidity associated with intracranial hemorrhage.

Background: The management of cerebrospinal fluid (CSF) rhinorrhea has evolved over the last two decades. We present here a review of our 11-year data on CSF rhinorrhea and its management at a tertiary care hospital in a developing country, with particular reference to the diagnosis, surgical management and outcome of the disease. Methods: The medical charts of all patients with a diagnosis of CSF rhinorrhea over an 11-year period were reviewed. The etiology of CSF rhinorrhea was classified into three categories: spontaneous, iatrogenic and traumatic. All the patients were divided into three categories based on the type of management as conservative, intracranial and transnasal endoscopic groups. Results: A total of 43 patients fulfilled our inclusion criteria and were included in the final analysis. Eleven of the 43 patients were managed conservatively, while 22 underwent intracranial repairs; 10 patients had transnasal endoscopic repairs. The primary success rate for the transnasal approach was 70% compared to 86% for the intracranial repair. Blood loss, special care unit (SCU) stay and total cost were found to be significantly less in the transnasal endoscopic group. Computed tomography (CT) cisternography was found to have the highest sensitivity and specificity. Further, no postoperative complications were found in the transnasal endoscopic group, while five patients from the intracranial group developed various complications. Conclusions: We conclude that the transnasal endoscopic approach has comparable success rates with the intracranial approach and significantly lower morbidity.

Background : Intrasphenoidal encephaloceles are extremely rare findings. Sternberg's canal is a lateral craniopharyngeal canal resulting from incomplete fusion of the greater wings of the sphenoid bone with the basisphenoid. It acts as a weak spot of the skull base, which may lead to develop a temporal lobe encephalocele protruding into the lateral recess of the sphenoid sinus (SS). Case Description : We present two cases of intrasphenoidal encephalocele due to persistence of the lateral craniopharyngeal canal. The first case presented with cerebrospinal fluid (CSF) rhinorrhea and the second one was referred to the neurosurgical department with CSF rhinorrhea and meningitis. Radiological investigations consisted of computed tomography (CT) scan, CT cisternography and magnetic resonance images in both cases. These imaging studies identified a herniated temporal lobe through a bony defect which communicates the middle cranial fossa with the lateral recess of the SS. Both patients underwent a transcranial repair of the encephalocele because of the previous failure of the endoscopic surgery. There was no complication related to the surgical procedure and no recurrence of CSF leakage occurred 2 and 3 years after surgery, respectively. Conclusion : Encephalocele within the lateral recess of the SS is a rare entity which must be suspected in patients who present with spontaneous CSF rhinorrhea. Congenital intrasphenoidal encephaloceles, which are located medial to the foramen rotundum, seem to be due to persistence of the Sternberg's canal. Transcranial approach is a good option when a transnasal approach had failed previously.

Background : Cerebral aneurysm rupture can lead to devastating neurological complications and present a complex problem to treat. We report a unique case of a ruptured posterior communicating artery (PCoA) aneurysm presenting with sudden and complete vision loss. Case Description : A 39-year-old man presented with the acute onset of severe headache and complete bilateral vision loss. The patient described headaches for several months prior to presentation. However, prior to the day of presentation, he had no visual disturbance. A CT angiogram (CTA) and magnetic resonance imaging (MRI) of the brain revealed a 1.6-cm, non-contrast enhancing suprasellar mass, eccentric to the left side, consistent with hemorrhagic mass. There was no obvious aneurysm or vascular malformation. The sella tursica was normal in appearance. The patient was taken for an immediate endoscopic endonasal transtuberculum approach for optic nerve decompression. Hematoma without an associated tumor was encountered and partially evacuated before aborting with resultant partial improvement in vision. A subsequent cerebral angiogram revealed an irregularly shaped, postero-laterally pointing, 2.5-mm left PCoA aneurysm. The patient was then taken for open clipping of the ruptured aneurysm. A large, fibrinous capsule was found over the superolateral aspect of the aneurysm. The ruptured aneurysm was secured with clips and the surrounding hematoma was evacuated. Conclusion : In the immediate postoperative period, the patient regained vision in the nasal field of his right eye. This case illustrates a unique presentation of a ruptured PCoA aneurysm, and thus must be considered in the differential diagnosis of a suprasellar hemorrhage resulting in visual loss in absence of a recognizable associated tumor.

Background : Surgery of skull base meningiomas by the lateral supraorbital (LSO) approach requires relaxed brain. Therefore, we assessed combined effects of the elements of neuroanesthesia on neurosurgical conditions during craniotomy. Methods : The anesthesiological and surgical charts of 66 olfactory groove, 73 anterior clinoidal, and 52 tuberculum sellae meningioma patients operated on by the senior author (J.H.) at the Department of Neurosurgery of Helsinki University Central Hospital, Helsinki, Finland, between September 1997 and August 2010, were retrospectively analyzed. Results : One-hundred fifty-four (82%) patients had good surgical conditions, and this was achieved by (1) elevating the head 20 cm above the cardiac level in all patients with only slightly lateral turn or neck flexion, (2) administering mannitol preoperatively in medium or large meningiomas (n = 60), (3) maintaining anesthesia with propofol infusion (n = 46) or volatile anesthetics (n = 107) also in patients with large tumors (n = 37), and (4) controlling intraoperative hemodynamics. Brain relaxation was satisfactory in 18 (10%) and poor in 15 (8%) patients. The median intraoperative blood loss was 200 (range, 0-2000) ml. Only 9% of patients received red blood cell transfusion. The median time to extubation was 18 (range, 8-105) min after surgery. Extubation time correlated with the patients' preoperative clinical status and the size of tumor but not with the modality of anesthesia. Conclusions : Slack brain during the LSO approach is achieved by correct patient positioning, preoperative mannitol, either by propofol or in small tumors inhaled anesthetics, and optimizing cerebral perfusion pressure. Under these circumstances, intraoperative brain swelling is prevented, bleeding is minimal, and no blood transfusions are needed.

Background : Surgical stabilization of injured spine in patients with complete spinal cord injury is a common practice despite the lack of strong evidence supporting it. The aim of this study is to compare clinical outcomes and cost-effectiveness of surgical stabilization versus conservative management of spinal injury in patients with complete deficits, essentially from a developing country's point of view. Methods : A detailed analysis of patients with traumatic spine injury and complete deficits admitted at the Aga Khan University Hospital, Pakistan, from January 2004 till January 2010 was carried out. All patients presenting within 14 days of injury were divided in two groups, those who underwent stabilization procedures and those who were managed non-operatively. The two groups were compared with the endpoints being time to rehabilitation, length of hospital stay, 30 day morbidity/mortality, cost of treatment, and status at follow up. Results : Fifty-four patients fulfilled the inclusion criteria and half of these were operated. On comparing endpoints, patients in the operative group took longer time to rehabilitation (P-value = 0.002); had longer hospital stay (P-value = 0.006) which included longer length of stay in special care unit (P-value = 0.002) as well as intensive care unit (P-value = 0.004); and were associated with more complications, especially those related to infections (P-value = 0.002). The mean cost of treatment was also significantly higher in the operative group (USD 6,500) as compared to non-operative group (USD 1490) (P-value < 0.001). Conclusion : We recommend that patients with complete SCI should be managed non-operatively with a provision of surgery only if their rehabilitation is impeded due to pain or deformity.

Background : We describe a new posterior dynamic stabilizing system that can be used to augment the mechanics of the degenerating lumbar segment. The mechanism of this system differs from other previously described surgical techniques that have been designed to augment lumbar biomechanics. The implant and technique we describe is an extension-limiting one, and it is designed to support and cushion the facet complex. Furthermore, it is inserted through an entirely percutaneous technique. The purpose of this technical note is to demonstrate a novel posterior surgical approach for the treatment of lumbar degenerative. Methods : This report describes a novel, percutaneously placed, posterior dynamic stabilization system as an alternative option to treat lumbar degenerative disk disease with and without lumbar spinal stenosis. The system does not require a midline soft-tissue dissection, nor subperiosteal dissection, and is a truly minimally invasive means for posterior augmentation of the functional facet complex. This system can be implanted as a stand-alone procedure or in conjunction with decompression procedures. Results : One-year clinical results in nine individual patients, all treated for degenerative disease of the lower lumbar spine, are presented. Conclusions : This novel technique allows for percutaneous posterior dynamic stabilization of the lumbar facet complex. The use of this procedure may allow a less invasive alternative to traditional approaches to the lumbar spine as well as an alternative to other newly developed posterior dynamic stabilization systems.

Background: The central sulcus may be located through magnetic resonance imaging (MRI) by identifying the ipsilateral inverted Omega shape. In a brain with a lesion in this area, its identification becomes a hard task irrespective of the technique applied. The aim of this study is to show the usefulness of the contralateral Omega sign for the location of tumors in and around the central sulcus. We do not intend to replace modern techniques, but to show an easy, cheap and relatively effective way to recognize the relationship between the central sulcus and the lesion. Methods: From July 2005 through December 2010, 43 patients with lesions in and around the central sulcus were operated using the contralateral Omega sign concept. Additionally, 5 formalin-fixed brains (10 hemispheres) were studied to clarify the anatomy of the central sulcus where the Omega shape is found. Results: The central sulcus has three genua. The middle genu is characterized by an inverted Omega-shaped area in axial sections known as the Omega sign. On anatomical specimens, Omega was 11.2 ± 3.35 mm in height, on average, and 18.7 ± 2.49 mm in width, at the base. The average distance from the medial limit of the Omega to the medial edge of the hemisphere was 24.5 ± 5.35 mm. Identification of the Omega sign allowed for the topographic localization of the contralateral central sulcus in all our surgical cases but one. Conclusion: The contralateral Omega sign can be easily and reliably used to clarify the topographic location of the pathology. Hence, it gives a quick preoperative idea of the relationships between the lesion and the pre- and post-central gyri.

Background: High-grade primary and metastatic central nervous system (CNS) tumors are common, deadly, and refractory to conventional therapy and continue to be therapeutically challenging. A key nodal transcriptional factor, the signal transducer and activator of transcription 3 (STAT3), drives the fundamental components of tumor malignancy and metastases in the CNS by enhancing proliferation, angiogenesis, invasion, metastasis, and immunosuppression. The introduction of STAT3 inhibitors in clinical trials for this patient population is imminent. Methods: STAT3 inhibitors have been extensively tested in a variety of preclinical murine models. Results: The STAT3 inhibitor, WP1066, has displayed marked efficacy with minimal toxicity against malignancy in murine models, including established intracerebral tumors. The mechanism of this in vivo efficacy of the STAT3 blockade agents is a combination of direct tumor cytotoxicity and immune cytotoxic clearance. Conclusions: Given their direct antitumor cytotoxic effects, STAT3 inhibitors may exert therapeutic activity in the monotherapy setting but may also have compelling use as immunotherapeutic modulators or as a salvage therapy.

Background: Intravesical instillations of live-attenuated Bacillus Calmette-Guérin (BCG) are a well-known and effective method for prevention and treatment of bladder carcinoma and carcinoma in situ. Although considered a safe procedure with rare side effects, local and systemic complications may occur. While long bone ostemolyelitis has been well described, very few reports of BCG spondylodiscitis exist in the literature. Case Description: A 67-year-old man developed low back pain, anorexia, and weight loss 11 months after a 6-week course of intravesical BCG instillations for the treatment of bladder carcinoma in situ. Imaging studies revealed L1-L2 spondylodiscitis with epidural and bilateral psoas abscesses. Tissue cultures obtained by percutaneous computed tomography-guided aspiration were positive for Mycobacterium bovis. Despite triple antituberculous therapy (isoniazid, rifampin, and ethambutol), clinical and radiological progression occurred. Therefore, L1 and L2 corpectomies with extensive debridement were performed, followed by 360° anterior-posterior instrumented fusion. After 20 months of follow-up, the patient remains asymptomatic and recurrence-free. Conclusion: Mycobacterium bovis spondylodiscitis is a rare complication of intravesical BCG therapy. Although medical therapy with antituberculous agents is the first-line treatment, surgical decompression, debridement, and stabilization may be necessary in refractory cases.

Background: Leukoencephalopathy, Calcification, and Cyst (LCC) is a syndrome describing the rare concurrence of these three unusual radiographic findings. Here, we describe the neurosurgical management in a patient afflicted with LCC and review the existing literature on surgical indications and outcomes. Case Description: A 24-year-old man presented with symptoms of progressive headache, gait imbalance and horizontal diplopia. Magnetic resonance imaging (MRI) showed radiographic findings typically associated with LCC, including a large pontine cyst with significant mass effect. The patient's symptoms resolved after open surgical cyst drainage. However, he suffered cyst re-accumulation 3 months after the initial procedure and ultimately underwent placement of a ventriculo-cysto-peritoneal shunt. At the 3-year follow-up, the patient remained symptom free with continued cyst decompression. Conclusion: Our case report suggests that ventriculo-cysto-peritoneal shunting appeared an effective strategy in LCC patients in whom the cyst fenestration failed. We present this case report in the context of the first systematic review of literature on neurosurgical management strategies for patients afflicted with LCC.

Background: Cerebral metastases are a common neurosurgical finding. Surgery confers several advantages to other therapies, including immediate symptomatic improvement, diagnosis, and relief from corticosteroid dependence. Here we evaluate patients with cerebellar metastases who underwent surgery and compare their findings to those in the literature, and address the benefit of avoiding ventriculo-peritoneal shunting in patients undergoing surgery. Methods: We performed a retrospective analysis involving 50 patients with cerebellar metastases who underwent surgical resection. Ventriculo-peritoneal shunts were placed in patients necessitating permanent CSF drainage. We evaluated presentation, diagnosis, complications, and outcome. Results: Our review included 21 males and 29 females, 29 to 82 years of age. Primary tumors included lung (48%), breast (14%), GI (14%), endometrial/ovarian (6%), melanoma (6%), sarcoma (4%), lymphoma (4%), laryngeal (2%), and other (2%). Clinical symptoms at presentation commonly were those secondary to elevated intracranial pressure and were the initial complaint in 34% of patients. Preoperatively, 29 patients were noted to have hydrocephalus. Importantly, 76% of these patients were able to avoid placement of a ventriculo-peritoneal shunt following surgery. Only two complications were noted in our series of 50 patients, including a symptomatic pseudomeningocele and a wound infection. No symptomatic postoperative hematoma developed in any surgical case. Conclusion: A review of the literature has shown a high complication rate in patients undergoing surgical resection of cerebellar metastases. We have shown that surgical resection of cerebellar metastases is a safe procedure and is effective in the treatment of hydrocephalus in the majority of patients harboring cerebellar lesions.

Background: Meningiomas are the most common benign brain tumors that are frequently followed-up by neurologists, general practitioners, and neurosurgeons. Some recent studies advocate the accurate volumetric method (VM) over measuring the linear maximum diameter although its clinical significance still remains unknown. The aim of this study is to directly compare the linear method (LM) and VM to delineate the characteristics of both measurements. Methods: Between 2003 and 2010, growth analysis using magnetic resonance imaging DICOM files was performed for 189 meningiomas in 161 patients at the Cleveland Clinic. In LM, a minimum increase of 2 mm in maximum diameter was defined as tumor growth. The absolute volume growth (VG, in cm ³ ) was calculated for each tumor. Results: Linear growth (LG) was seen in 71 tumors (37.6%) within the median follow-up of 2.0 years. These tumors with LG showed a mean VG of 2.80 cm ³ . Some large LG-positive tumors can be larger than estimated from LG. In addition, the skull base location was correlated to greater VG. On the other hand, 118 tumors without LG demonstrated the minimal actual volume increase, i.e., mean VG of 0.16 cm ³ . Although a small subset of these LG-negative tumors might have slightly high VG when they were large, the location of tumor had no correlation to VG. Conclusions: Our data demonstrated some important precautions in measuring the tumor growth. We believe that it is mandatory in the conservative management of meningiomas to correctly understand benefits and potential limitations of different measurement methods utilized.

Background: Despite refinements in neurotrauma care, the morbidity and mortality of severe traumatic brain injury (TBI) in pediatric patients remains high. We report a novel approach to the surgical management of increased intracranial pressure in severe TBI utilizing an in situ free-floating craniectomy technique, which was originally devised as a creative solution to the unique challenges in a Haitian field hospital following the 2010 earthquake. Case Description: A 13-month-old Haitian boy presented to Project Medishare field hospital in Port-au-Prince with left hemiplegia, a bulging fontanelle, and increasing lethargy following a traumatic head injury 4 days prior. An urgent craniectomy was performed based on clinical grounds (no brain imaging was available). A standard trauma flap incision was made, followed by a hemicraniectomy and expansion duraplasty. A small hematoma was evacuated. Frontal, temporal, and parietal bone flaps were placed on the dura in approximation to their normal anatomical configuration, but not affixed, leaving space for further brain edema, and the scalp was closed. The child experienced favorable peri-operative and early postoperative results. Conclusion: In situ free-floating craniectomy, while devised as a creative solution to limited resources in a natural disaster zone, may offer advantages over more traditional techniques.

Background: We present a review of the results of the current surgical management of acute cervical spine injuries in the Federal Capital Territory, Abuja, Nigeria. This is the first detailed retrospective study on the surgical management of patients with cervical spine injuries from Nigeria. Methods: The medical reports of patients with traumatic cervical spine and spinal cord injuries undergoing surgery from 1 August 2009 till 30 August 2010 were reviewed. Management and early results of outcome were ascertained and detailed consecutively in a prospective Microsoft Office Access^® database (Microsoft Group of Companies). Frankel grading was used for pre- and immediate post-operative evaluation (within 48 hours). The Barthel index (BI) was used to classify patients as dependent or independent at follow-up. Results: Twenty consecutive patients presented with acute cervical spine and spinal cord injuries since August 2009. Twenty anterior cervical spine decompression and fixation with an iliac graft and an anterior cervical plate (ACDF) were performed in 18 patients. All operations were performed with general anaesthesia using standard techniques but without a microscope or a high speed drill. Of the 18 patients who were operated, 4 patients died within a short period following surgical intervention. Seven patients have made a full recovery and seven remain fully dependent. Only two of the dependent quadriplegic patients have become reintegrated back into the society. Conclusion: The management of spinal cord injuries in Abuja is evolving. The operations were performed adequately with much limited complement of equipment. Poor intensive care therapy is a major challenge and improvements in this area of care will likely lead to better patient outcomes.

Background: The occurrence of primitive neuroectodermal tumors (PNET) in patients with neurofibromatosis type 1 (NF1) has only been reported in two other cases in English-Language literature. Owing to the rarity of intraspinal PNET and the extremely high gene mutation variability in NF1, there is currently no conclusive evidence to suggest that PNET is associated with NF1. Here, we report a case of intradural PNET in a patient with NF1. Case Description: A 27-year-old male underwent a C1-C3 laminectomy for resection of an intramedullary mass. Histopathology and immunohistopathology analysis was performed. Microscopic examination and immunohistochemical staining indicated the mass was a primitive neuroectodermal tumor. Within 1 month after tumor resection, the patient developed leptomeningeal carcinomatosis. The patient was not a candidate for radiation therapy but underwent palliative systemic chemotherapy. He subsequently developed neutropenia and died 3 months after tumor resection. Conclusion: To our knowledge, this is the first reported intraspinal PNET associated with NF1. Genetic analysis of CNS PNETs suggests a possible correlation, but larger case series are needed to support this theory.

Background: Tinnitus, a profoundly widespread auditory disorder, is characterized by the perception of sound in the absence of external stimulation. The aim of this work is to review the various surgical treatment options for tinnitus, targeting the various disruption sites along the auditory pathway, as well as to indicate novel neuromodulatory techniques as a mode of tinnitus control. Methods: A comprehensive analysis was conducted on published clinical and basic neuroscience research examining the pathophysiology and treatment options of tinnitus. Results: Stereotactic radiosurgery methods and microvascular decompressions are indicated for tinnitus caused by underlying pathologies such as vestibular schwannomas or neurovascular conflicts of the vestibulocochlear nerve at the level of the brainstem. However, subsequent hearing loss and secondary tinnitus may occur. In patients with subjective tinnitus and concomitant sensorineural hearing loss, cochlear implantation is indicated. Surgical ablation of the cochlea, vestibulocochlear nerve, or dorsal cochlear nucleus, though previously suggested in earlier literature as viable treatment options for tinnitus, has been shown to be ineffective and contraindicated. Recently, emerging research has shown the neuromodulatory capacity of the somatosensory system at the level of the trigeminal nerve on the auditory pathway through its inputs at various nuclei in the central auditory pathway. Conclusion: Tinnitus remains to be a difficult disorder to treat despite the many surgical interventions aimed at eliminating the aberrant neuronal activity in the auditory system. A promising novel neuromodulatory approach using the trigeminal system to control such a bothersome and difficult-to-treat disorder deserves further investigation and controlled clinical trials.

Background: Gliomas that aggregate in families with history of malignancy may have an inheritable genetic basis. Gliomas can occur in several well known tumor syndromes. However, their occurrence in the absence of these syndromes is quite rare. High-grade gliomas, such as glioblastoma multiforme (GBM), are the most common and most lethal primary cancers of the central nervous system (CNS). Case Description: We present a case of two brothers both diagnosed with GBM. Both siblings underwent biopsy with debulking of the tumors by different surgeons. Only one sibling elected to undergo chemotherapy and radiation. Cytogenetic studies were possible only on one sibling and the tumor specimen revealed multiple chromosomal abnormalities, including triploidies 4, 8, 12, 22 and loss of heterozygosity of 1p, 9p, and 10. Histological samples for both tumors were similar, both revealing increased cellularity consisting of gemistocytic astrocytes, central necrosis, and microvascularization. Conclusion: We present two brothers who display a rare familial relationship in the development of their GBMs. Supplementary and improved genetic studies may allow for specific treatment modalities as certain genetic abnormalities have better response to tailored treatments and carry better prognoses.

Background: The growing number of community hospitals with neurointerventional services over the past decade has changed the type and complexity of cerebral aneurysms referred to tertiary centers. The authors hypothesized that this would be reflected in changes in the location frequencies of aneurysms treated now compared to before the widespread institution of endovascular coiling. Methods: Using a prospectively collected aneurysm database, aneurysm location frequencies were retrospectively reviewed for the last 200 consecutively treated aneurysms (2009-2010) and 200 consecutive aneurysms treated starting from May 1999 to December 2000. International Subarachnoid Aneurysm Trial (ISAT) aneurysm location nomenclature was utilized. Two-tailed Student's t-tests were used to compare means and Fisher exact tests were used to compare proportions. Results: The location frequencies of all aneurysms (ruptured and unruptured) treated in the 2000 epoch as compared to the modern epoch showed significant changes for middle cerebral aneurysms (12.0% vs. 21.0%, P = 0.014), posterior communicating (21.0% vs. 13.0%, P = 0.0001), and para-ophthalmic aneurysms (10.0% vs. 25.5%, P = 0.0002). For unruptured/elective aneurysms, the change in posterior communicating aneurysms was even more pronounced (27.8% vs 3.6%, P = 0.0001). The rate of aneurysm coiling at the center rose from 26% to 37% (P = 0.02). Conclusions: The significant reduction in the referrals to our tertiary center of less technically complex aneurysms (posterior communicating segment) and increased referrals of aneurysms not as amenable to coil embolization (middle cerebral artery) is likely attributable to the growth of neurointerventional services at community hospitals over the past 10 years.

Background: Choroid plexus papilloma (CPP) can develop at a primary intraparenchymal location completely unrelated to the ventricular system. Here, we present a case of CPP that was difficult to diagnose preoperatively. Case Description: Preoperative imaging and operative findings showed that the tumor originated entirely within the cerebrum parenchyma, with no connections between the tumor and the ventricular system. Histopathological examination of the tumor revealed a papillary structure with a single layer of well-differentiated columnar epithelium in the lesion. Furthermore, part of this lesion had infiltrated the cerebral parenchyma. Therefore, the tumor was diagnosed as CPP, and the diagnosis was confirmed by immunohistological examination. Conclusions: CPP originating as intraparenchymal growths are extremely rare. Origins of extraventricular CCP are discussed in the context of the literature.

Background: The neurosurgical procedure of hinge decompressive craniectomy (hDC), or hinge craniotomy (HC), as described from units in the advanced countries makes use of metallic implants, usually titanium plates and screws, which may not be economically viable in resource-limited practice settings. Methods: We describe our surgical techniques for performing this same procedure of hDC in a developing country using the patient's own temporalis muscle instead of any other potentially costly implants. Results: The technique as described appears to be successful in achieving intracranial decompression in cases of traumatic brain swelling in which it has been used. Clinical and radiological illustrations of the feasibility, and practical utility, of the procedures in four clinical scenarios of traumatic brain injury are presented. Like all other techniques of HC, this "new" surgical technique of hDC temporalis saves the survivors the added imperative of future cranioplasty of the usual postcraniectomy skull defect. Unlike the others, the procedure eliminates the added cost of the metallic implants needed to perform the former techniques. Conclusions: The procedure of hDC temporalis appears to be a viable option for performing the surgical procedure of HC and has added cost-cutting economic benefits for resource-limited practice settings.

Background: Worldwide, Salmonella enteritidis (SE) is becoming a common cause of gastrointestinal infections by contaminated food products, mainly eggs. Extra-intestinal manifestations such as brain abscess are more commonly associated with Salmonella typhimurium and are rare in adults. We report the clinical features, treatment outcomes and risk factors predisposing our patient to Salmonella enteritidis brain abscess and discuss relevant literature. Case Description: A 57-year-old-man developed SE subdural empyema, abscess and possible ventriculitis following reoperation for progression of a right temporal glioblastoma. He initially presented with rapidly worsening headaches over a few days, with a wound discharge and associated meningeal signs. An emergent wound washout revealed pus in the epidural, subdural space and resection cavity. An external ventricular drain (EVD) was placed and cultures revealed gram negative rods. Timely intervention, EVD, and antibiotics resulted in complete resolution. Nine cases of Salmonella abscess associated with primary brain tumor have been reported in literature, most frequently caused by SE in association with glioblastoma multiforme (GBM). We describe our management and outcome in addition to discussing neurosurgical literature on the reported cases. Conclusions: Re-operative tumor surgery has a higher incidence of post-operative infections, with Gram positive cocci being the most common pathogens. Predisposing factors reported for intracranial salmonellosis include compromised immunity, diabetes, HIV, and recent travel. Chronic corticosteroid use, multiple regimens of chemotherapy, and regions of tumor necrosis likely potentiate this rare infection in GBM patients.

Background: While numerous laboratory studies have searched for neuroprotective treatment approaches to traumatic brain injury, no therapies have successfully translated from the bench to the bedside. Concussion is a unique form of brain injury, in that the current mainstay of treatment focuses on both physical and cognitive rest. Treatments for concussion are lacking. The concept of neuro-prophylactic compounds or supplements is also an intriguing one, especially as we are learning more about the relationship of numerous sub-concussive blows and/or repetitive concussive impacts and the development of chronic neurodegenerative disease. The use of dietary supplements and herbal remedies has become more common place. Methods: A literature search was conducted with the objective of identifying and reviewing the pre-clinical and clinical studies investigating the neuroprotective properties of a few of the more widely known compounds and supplements. Results: There are an abundance of pre-clinical studies demonstrating the neuroprotective properties of a variety of these compounds and we review some of those here. While there are an increasing number of well-designed studies investigating the therapeutic potential of these nutraceutical preparations, the clinical evidence is still fairly thin. Conclusion: There are encouraging results from laboratory studies demonstrating the multi-mechanistic neuroprotective properties of many naturally occurring compounds. Similarly, there are some intriguing clinical observational studies that potentially suggest both acute and chronic neuroprotective effects. Thus, there is a need for future trials exploring the potential therapeutic benefits of these compounds in the treatment of traumatic brain injury, particularly concussion.

Background: Chordomas are rare tumors that arise from the remnants of embryonic notochord anywhere along the neuroaxis. Even though they may occur in an extraosseous intradural location, the most common sites include the sacrococcygeal and clivus regions. The authors report a unique presentation encompassing the pineal region with metastasis to the peritoneum after a ventriculoperitoneal (VP) shunt procedure and review the current knowledge about their pathophysiology and management. The presentation and clinical history endorse the idea that intradural extraosseous chordomas may be distinct from ecchordosis physaliphora and probably do not derive from it. Case Description: An 18-year-old male with previous history of VP shunt presented to the emergency room with pain and abdominal distension. Computed tomography (CT) scans revealed a mass in the pineal region and in the abdominal cavity. Histopathologic exams showed chordoma in both abdominal and cranial samples. The patient died due to systemic complications. Conclusion: The authors hypothesized that notochord remnants may subsist within the brain and occasionally may generate a neoplastic lesion.

Background: The most frequent intraocular malignant tumor is choroidal melanoma (CM). Although brain metastasis is a common feature of other types of cancers, metastasis of CM to the brain is a rare entity. Case Description: The authors report a case of a 28-year-old woman presenting with a single brain metastasis, 10 years after the treatment of a CM. She underwent a total en-bloc resection of the lesion, and the diagnosis was confirmed histopathologically. The patient concomitantly received whole-brain irradiation therapy combined with chemotherapy, with a survival period of 24 months. Conclusion: The present case report draws attention to the necessity of a close and lifelong follow-up of patients treated for this malignancy. The international literature is also reviewed.

Background: The retromastoid approach has been effective in exposing the cerebellopontine angle for resection of a variety of lesions, including vestibular schwannomas and decompression of cranial nerves. The following incisions and their variations have been most commonly used for the retromastoid approach: linear (and its variations, such as "lazy S-shaped") and "C-shaped" incision. Methods: Herein, we describe a curvilinear incision and compare its advantages and disadvantages with the other previously described incisions based on the senior author's experience with 120 retromastoid operations. Results: The senior author has used the curvilinear incision for the last 70 of 120 patients who underwent retromastoid operations. Of these, one patient encountered postoperative cerebrospinal fluid (CSF) leakage through the incision, requiring a repeat operative wound revision, and one patient suffered from a soft asymptomatic pseudomeningocele. Among the initial 50 patients who underwent a linear incision, one patient suffered from a CSF leakage managed with local wound care and another patient required a repeat operation for a tense pseudomeningocele. No wound breakdown or infection was encountered in either group. Conclusions: The curvilinear incision is simple and efficient and may provide a shorter working distance and protect the suboccipital muscles and associated neurovascular bundle.

Background: Meningioma firmness is a critical factor that influences ease of resection and risk, notably when operating on tumors intimate with neurovascular structures such as the mesial sphenoid wing. This study develops a predictive tool using preoperative magnetic resonance imaging (MRI) characteristics to determine meningioma consistency. Methods: 101 patients with intracranial meningioma (50 soft/51 firm) were included. MRI characteristics of 38 tumors (19 soft/19 firm) were retrospectively reviewed to identify preoperative imaging features that were then correlated with intraoperative description of the tumor as either "soft and/or suckable" or "firm and/or fibrous." Criteria were developed to predict consistency and then blindly applied to the remaining 63 meningiomas (31 soft/32 firm). Results: The overall sensitivities for detecting soft and firm consistency were 90% and 56%, respectively (95% CI = 73-97% and 38-73%; P < 0.001). Compared to gray matter, meningiomas that were T2 hypointense were almost always firm. Soft meningiomas were hyperintense on T2 and hypointense on T1. Soft meningiomas were slightly larger and less likely to be associated with edema. There was a slight preponderance of firm meningiomas in the infratentorial compartment. Grade of meningioma was not predictive. Contrast enhancement, diffusion restriction, changes in overlying bone, intratumoral cysts, and angiographic features were not predictable. Conclusions: This tool using T1 and T2 series predicts meningioma consistency. Such knowledge should assist the surgeon in preoperative planning and counseling.

Background: Congenital unilateral hydrocephalus is an uncommon entity occurring almost exclusively in children. Atresia, stenosis, membranous occlusion and even functional obstruction of the foramen of Monro have been described to be the main cause of this type of hydrocephalus. There are two options available in the surgical management of unilateral hydrocephalus: one is the placement of shunt CSF diversion from the dilated ventricle and the other is fenestration of the occluded foramen of Monro or septum pellucidum by endoscopy or by stereotactic method. Migration of the ventriculoperitoneal (VP) shunt in or out of ventricles is not so uncommon, but the relocation of the ventricular tip of a catheter from the ventricle into the quadrigeminal cisterns and superior vermis in association with ventriculostomy is extremely rare. Spontaneous ventriculostomy is a rare event and results from spontaneous rupture of a ventricle into the subarachnoid space. Case Description: A 5½-month-old baby with a right-sided congenital unilateral hydrocephalus underwent a VP shunt andhad experienced an uneventful outcome. Four years later on an MR imaging examination, the tip of the ventricular catheter passing through the medial wall of the ventricle and the quadrigeminal cistern was found to be situated in the superior vermis. During the follow-up period, there were no neurological difficulties. The cognitive and motor skill development corresponded well with the child's age. It transpired that the hydrocephalic ventricle reduced its size dramatically to normal. Conclusion: We have described the extremely rare site of the relocation of the ventricular catheter after the treatment of the congenital unilateral hydrocephalus by VP shunting. Spontaneous ventriculostomy as a rare phenomenon may be the explanation of the relocation of the ventricular catheter.

Background: Anterior clinoidectomy is a difficult but important part of surgery for a variety of parasellar, proximal carotid and central skull base pathologies. First developed intradurally nearly 60 years ago, the promotion of an extradural technique decades later offered an approach with a different set of difficulties, risks and benefits. Many recent studies have demonstrated that there is no consensus about the "correct" side of the dura from which to remove the anterior clinoid process in a number of pathologies. Here, we review and compare the current techniques for intra- and extradural clinoidectomy and describe a hybrid alternative technique. Methods: We used a hybrid method to potentially engage the advantages of the intradural and extradural techniques. The hybrid method starts with an extradural sphenoid wing osteotomy to the level of the superior orbital fissure (SOF). The dura is then incised parallel to the sphenoid wing lateral to the SOF, and the need for further bony removal, including clinoidectomy, is assessed after gentle elevation of the frontal lobe and release of cerebrospinal fluid through opening the optico-carotid cisterns and inspection of the pathology in relation to the clinoid. Sylvian fissure may be dissected to relieve retraction on the frontal lobe. Results: The hybrid method allows an early identification of the optic nerve and its protection during clinoidectomy. The operator leaves the dura medial to the SOF intact and the clionoidectomy proceeds in an extradural fashion while intradural inspection periodically is performed to assess the extent of necessary extradural bony removal. Conclusion: The hybrid method theoretically can be used as a versatile method under some circumstances. Cutting the dura along the sphenoid wing will prevent the dural layers from obscuring the clinoid and offers intradural visualization to monitor the lesion and potentially tailor bony removal.

Background : Spinal fusion is the most rapidly increasing type of lumbar spine surgery for various lumbar degenerative pathologies. The surgical treatment of lumbar spine degenerative disc disease may involve decompression, stabilization, or arthroplasty procedures. Lumbar disc athroplasty is a recent technological advance in the field of lumbar surgery. This study seeks to determine the clinical impact of anterior lumbar disc replacement on the surgical treatment of lumbar spine degenerative pathology. This is a retrospective assessment of the Nationwide Inpatient Sample (NIS). Methods : The NIS was searched for ICD-9 codes for lumbar and lumbosacral fusion (81.06), anterior lumbar interbody fusion (81.07), and posterolateral lumbar fusion (81.08), as well as for procedure codes for revision fusion surgery in the lumbar and lumbosacral spine (81.36, 81.37, and 81.38). To assess lumbar arthroplasty, procedure codes for the insertion or replacement of lumbar artificial discs (84.60, 84.65, and 84.68) were queried. Results were assayed from 2000 through 2008, the last year with available data. Analysis was done using the lme4 package in the R programming language for statistical computing. Results : A total of nearly 300,000 lumbar spine fusion procedures were reported in the NIS database from 2000 to 2008; assuming a representative cross-section of the US health care market, this models approximately 1.5 million procedures performed over this time period. In 2005, the first year of its widespread use, there were 911 lumbar arthroplasty procedures performed, representing 3% of posterolateral fusions performed in this year. Since introduction, the number of lumbar spine arthroplasty procedures has consistently declined, to 653 total procedures recorded in the NIS in 2008. From 2005 to 2008, lumbar arthroplasties comprised approximately 2% of lumbar posterolateral fusions. Arthroplasty patients were younger than posterior lumbar fusion patients (42.8 ± 11.5 vs. 55.9 ± 15.1 years, P < 0.0000001). The distribution of arthroplasty procedures was even between academic and private urban facilities (48.5% and 48.9%, respectively). While rates of posterolateral lumbar spine fusion steadily grew during the period (OR 1.06, 95% CI: 1.05-1.06, P < 0.0000001), rates of revision surgery and anterior spinal fusion remained static. Conclusions : The impact of lumbar arthroplasty procedures has been minimal. Measured as a percentage of more common lumbar posterior arthrodesis procedures, lumbar arthroplasty comprises only approximately 2% of lumbar spine surgeries performed in the United States. Over the first 4 years following the Food and Drug Administration (FDA) approval, the frequency of lumbar disc arthroplasty has decreased while the number of all lumbar spinal fusions has increased.

Background : C1 fracture accounts for 2% of all spinal column injuries and 10% of cervical spine fractures, and is most frequently caused by motor vehicle accidents and falls. We present a rare case of C1 anterior arch fracture following standard foramen magnum decompression for Chiari malformation type 1. Case Description : A 63-year-old man underwent standard foramen magnum decompression (suboccipital craniectomy and C1 laminectomy) under a diagnosis of Chiari malformation type 1 with syringomyelia in June 2009. The postoperative course was uneventful until the patient noticed progressive posterior cervical pain 5 months after the operation. Computed tomography of the upper cervical spine obtained 7 months after the operation revealed left C1 anterior arch fracture. The patient was referred to our hospital at the end of January 2010 and C1-C2 posterior fusion with C1 lateral mass screws and C2 laminar screws was carried out in March 2010. Complete pain relief was achieved immediately after the second operation, and the patient resumed his daily activities. Conclusion : Anterior atlas fracture following foramen magnum decompression for Chiari malformation type 1 is very rare, but C1 laminectomy carries the risk of anterior arch fracture. Neurosurgeons should recognize that fracture of the atlas, which commonly results from an axial loading force, can occur in the postoperative period in patients with Chiari malformation.

Background : Retroperitoneal hemorrhage is a life-threatening condition. This is the first reported case of rupture of one of multiple thoraco-lumbar artery aneurysms associated with a metameric paraspinal vascular lesion. Case Description : A 77-year-old female patient presented to the emergency room with a new onset of left-sided low back pain shooting down the leg associated with weakness, numbness, and inability to walk. On physical examination, there was a notable left paraspinal swelling with a harsh bruit audible in the same area, left flank ecchymosis and a positive straight leg raising test. A computed tomography (CT) scan showed a large retroperitoneal hematoma. Digital subtraction angiography showed a large left paraspinal high-flow arteriovenous lesion, with large arterial aneurysms of the left T11, T12, and L1 segmental arteries. The patient was successfully treated with endovascular aneurysm embolization using coils and Onyx-34. Six months following the procedure, the patient had fully recovered, and a follow-up angiogram showed no residual or recurrent aneurysms. Conclusion : Thoraco-lumbar artery aneurysms have never previously been described in association with a metameric paraspinal vascular malformation. We report a case of retroperitoneal hemorrhage due to rupture of one of several high-flow artery aneurysms of a paraspinal arteriovenous malformation (AVM). The diagnosis was made on CTA, MRI, and angiography, and the lesion was successfully treated by transarterial embolization.

Background : Psammomatous melanotic schwannomas (PMS) of the spine may be a component of the Carney complex in 50% of cases and is inherited in an autosomal dominant manner. Most PMS are benign and frequently associated with lentiginous pigmentation; cardiac, cutaneous, or breast myxomas; endocrine overactivity; and cutaneous blue nevi. These tumors are characterized by melanin containing cells having ultrastructural characteristics of Schwann cells. Case Description : Two patients had spinal PMS that were surgically resected with adjacent local radiotherapy, followed by local recurrence and metastasis. The aggressive nature of this tumor is reported. Conclusion : Spinal PMS are rarely malignant with local recurrence and distal metastases. Inquiry into the patient's and family members' hereditary background for the Carney complex is important to avoid overlooking potential lethal associated abnormalities.

Background : Giant distal anterior cerebral artery (DACA) aneurysms are extremely rare, with only 32 cases reported in the literature. Most giant DACA aneurysms have features that make standard neck clipping difficult, and bypass surgery is sometimes required, although this surgery was performed in only three reported cases. This report presents the fourth case treated with bypass surgery. Case Description : A 69-year-old female presented with an unruptured thrombosed giant DACA aneurysm. She underwent wrapping operation 7 years before, but radiological imaging revealed enlargement of the aneurysm at the left pericallosal artery (PerA)-callosomarginal artery (CMA) junction. Before operation, three different strategies were considered for bypass surgery in case the neck could not be clipped. Aneurysm resection and left proximal PerA-CMA end-to-end anastomosis were successfully performed under intraoperative digital subtraction angiography (DSA) and motor-evoked potential (MEP) monitoring. Conclusion : Most DACA aneurysms are located at the PerA-CMA junction. In some cases, adequate retrograde flow to the distal PerA from the posterior or middle cerebral artery can be expected, making distal PerA reconstruction unnecessary. Moreover, when the distal PerA is cut, proximal PerA-CMA end-to-end anastomosis can be easily performed because of reduced tension in both vessels. We therefore conclude that this strategy should be utilized for treating such patients. We also presented here the effectiveness of intraoperative modalities, such as intraoperative DSA and MEP monitoring, for performing a safe operation.

Background : Based on numerous reports citing high sensitivity and specificity of non-invasive imaging [e.g. computed tomography angiography (CTA) or magnetic resonance angiography (MRA)] in the detection of intracranial aneurysms, it has become increasingly difficult to justify the role of conventional angiography [digital subtraction angiography (DSA)] for diagnostic purposes. The current literature, however, largely fails to demonstrate the practical application of these technologies within the context of a "real-world" neurosurgical practice. We sought to determine the proportion of patients for whom the additional information gleaned from 3D rotational DSA (3DRA) led to a change in treatment. Methods : We analyzed the medical records of the last 361 consecutive patients referred to a neurosurgeon at our institution for evaluation of "possible intracranial aneurysm" or subarachnoid hemorrhage (SAH). Only those who underwent non-invasive vascular imaging within 3 months prior to DSA were included in the study. For asymptomatic patients without a history of SAH, aneurysms less than 5 mm were followed conservatively. Treatment was advocated for patients with unruptured, non-cavernous aneurysms measuring 5 mm or larger and for any non-cavernous aneurysm in the setting of acute SAH. Results : For those who underwent CTA or MRA, the treatment plan was changed in 17/90 (18.9%) and 22/73 (30.1%), respectively, based on subsequent information gleaned from DSA. Several reasons exist for the change in the treatment plan, including size and location discrepancies (e.g. cavernous versus supraclinoid), or detection of a benign vascular variant rather than a true aneurysm. Conclusions : In a "real-world" analysis of intracranial aneurysms, DSA continues to play an important role in determining the optimal management strategy.

Background : Although the usage of combined motor and sensory intraoperative monitoring has been shown to improve the surgical outcome of patients with cervical myelopathy, the role of transcranial electric motor evoked potentials (tceMEP) used in conjunction with somatosensory evoked potentials (SSEP) in patients presenting with radiculopathy but without myelopathy has been less clear. Methods : We retrospectively reviewed all patients (n = 57) with radiculopathy but without myelopathy, undergoing anterior cervical decompression and fusion at a single institution over the past 3 years, who had intraoperative monitoring with both tceMEPs and SSEPs. Results : Fifty-seven (100%) patients presented with radiculopathy, 53 (93.0%) with mechanical neck pain, 35 (61.4%) with motor dysfunction, and 29 (50.9%) with sensory deficits. Intraoperatively, 3 (5.3%) patients experienced decreases in SSEP signal amplitudes and 4 (6.9%) had tceMEP signal changes. There were three instances where a change in neuromonitoring signal required intraoperative alteration of the surgical procedure: these were deemed clinically significant events/true positives. SSEP monitoring showed two false positives and two false negatives, whereas tceMEP monitoring only had one false positive and no false negatives. Thus, tceMEP monitoring exhibited higher sensitivity (33.3% vs. 100%), specificity (95.6% vs. 98.1%), positive predictive value (33.3% vs. 75.0%), negative predictive value (97.7% vs. 100%), and efficiency (91.7% vs. 98.2%) compared to SSEP monitoring alone. Conclusions : Here, we present a retrospective series of 57 patients where tceMEP/SSEP monitoring likely prevented irreversible neurologic damage. Though further prospective studies are needed, there may be a role for combined tceMEP/SSEP monitoring for patients undergoing anterior cervical decompression without myelopathy.

Background : In the setting of a deep brain stimulation (DBS) lead with defective electrical circuitry, potential patient morbidity and additional surgery may be avoided if impedance testing of the brain lead is performed prior to final lead implantation. In the present report, detection of a short circuit upon lead placement and prior to lead anchoring was detected utilizing recently released DBS hardware and software (Medtronic, Minneapolis, MN). This report suggests that neurosurgeons need to be aware and consider the use of the newly available DBS testing equipment. Methods : During the first DBS lead placement in a 69-year-old man with advanced idiopathic Parkinson's disease undergoing bilateral subthalamic nucleus DBS over staged procedures, test stimulation and lead impedance testing were accomplished prior to lead anchoring. An external neurostimulator (ENS) was affixed to an updated clinician programmer and connected to the DBS lead with a screening cable specific for the ENS and DBS. Results : Impedance testing demonstrated a short circuit involving the 1 and 3 lead-electrode bipolar combination in a visually intact lead. The lead was replaced, repeat impedance testing and test stimulation were completed and the intact lead was secured. Subsequent DBS surgeries were completed uneventfully. The lead abnormality was verified by the manufacturer. Conclusions : This case highlights a new method to test DBS lead circuitry at the time of placement. The method may also be employed to directly test lead integrity when localizing a DBS system short or open circuit of unclear etiology. Our case suggests that the method is valuable and should be utilized.

Background : Post-transplantation primary central nervous system lymphoma (PT-PCNSL) is a rare neoplasm that can develop within months to years after transplantation, and imaging often reveals multiple lesions with homogeneous or ring enhancement. The clinical and imaging presentation of PT-PCNSL can often be nonspecific and present a diagnostic challenge. Case Description : A 56-year-old woman presented to a tertiary university emergency room with altered mental status 15 months after undergoing renal transplantation. On brain MRI, she was found to have three rim-enhancing mass lesions, and biopsy revealed PT-PCNSL. Conclusion : There has been a steady increase in the number of patients living following organ transplantation in the United States and an increasing likelihood that PT-PCNSL will increasingly be encountered in neurosurgical practice. We present here a case of PT-PCNSL and a brief review of the relevant clinical characteristics, treatment options, and prognosis of PT-PCNSL.

Background : Perineural cysts of the sacrum, or Tarlov cysts, are cerebrospinal fluid (CSF)-filled sacs that commonly occur at the intersection of the dorsal root ganglion and posterior nerve root in the lumbosacral spine. Although often asymptomatic, these cysts have the potential to produce significant symptoms, including pain, weakness, and/or bowel or bladder incontinence. We present a case in which the sacral roof is removed and reconstructed via plated laminoplasty and describe how this technique could be of potential use in maximizing outcomes. Methods : We describe technical aspects of a sacral laminoplasty in conjunction with cyst fenestration for a symptomatic sacral perineural cyst in a 50-year-old female with severe sacral pain, lumbosacral radiculopathy, and progressive incontinence. This patient had magnetic resonance imaging (MRI) and computed tomography (CT)-myelographic evidence of a non-filling, 1.7 Χ 1.4 cm perineural cyst that was causing significant compression of the cauda equina and sacral nerve roots. This surgical technique was also employed in a total of 18 patients for symptomatic tarlov cysts with their radiographic and clinical results followed in a prospective fashion. Results : Intraoperative images, drawings, and video are presented to demonstrate both the technical aspects of this technique and the regional anatomy. Postoperative MRI scan demonstrated complete removal of the Tarlov cyst. The patient's symptoms improved dramatically and she regained normal bladder function. There was no evidence of radiographic recurrence at 12 months. At an average 16 month followup interval 10/18 patients had significant relief with mild or no residual complaints, 3/18 reported relief but had persistent coccydynia around the surgical area, 2/18 had primary relief but developed new low back pain and/or lumbar radiculopathy, 2/18 remained at their preoperative level of symptoms, and 1/18 had relief of their preoperative leg pain but developed new pain and neurological deficits. Conclusions : Sacral laminoplasty and microscopic cystic fenestration is a feasible approach in the operative treatment of this difficult, and often controversial, spinal pathology. This technique may be used further and studied in an attempt to minimize potential surgical morbidity, including CSF leaks, cyst recurrence, and sacral insufficiency fractures.

Background : The nucleus caudalis dorsal root entry zone (DREZ) surgery is used to treat intractable central craniofacial pain. This is the first journal publication of DREZ lesioning used for the long-term relief of an intractable chronic traumatic headache. Case Description : A 40-year-old female experienced new-onset bi-temporal headaches following a traumatic head injury. Despite medical treatment, her pain was severe on over 20 days per month, 3 years after the injury. The patient underwent trigeminal nucleus caudalis DREZ lesioning. Bilateral single-row lesions were made at 1-mm interval between the level of the obex and the C2 dorsal nerve roots, using angled radiofrequency electrodes, brought to 80°C for 15 seconds each, along a path 1 to 1.2 mm posterior to the accessory nerve rootlets. The headache improved, but gradually returned. Five years later, her headaches were severe on over 24 days per month. The DREZ surgery was then repeated. Her headaches improved and the relief has continued for 5 additional years. She has remained functional, with no limitation in instrumental activities of daily living. Conclusions : The nucleus caudalis DREZ surgery brought long-term relief to a patient suffering from chronic traumatic headache.

Objective : We describe a rare case of a patient with subarachnoid hemorrhage (SAH) due to a ventral dissecting mid-basilar aneurysm that was treated surgically. One week after surgery, the patient experienced sudden deterioration due to a new SAH caused by the development of a new aneurysm of the basilar trunk distinct from the previously clipped aneurysm. Case Description : A 54-year-old woman with acute subarachnoid hemorrhage was found to have a small, broad-based aneurysm arising from the ventral aspect of the mid-basilar artery. This complicated lesion was treated with a microsurgical clipping via a translabyrinthine pre-sigmoidal sub-temporal approach. One week postoperatively, the patient suffered a new SAH and was found to have developed a distinct basilar artery aneurysm. The patient was returned to the Operating Room for microsurgical clipping via the previous craniotomy. After surgery, the patient made a slow, but steady, recovery. She underwent repeated angiographic imaging, demonstrating a stable appearance. Two years post surgery, the patient had returned to work and had no obvious neurological deficit, with the exception of unilateral iatrogenic hearing loss. Conclusion : We describe a rare case of multiple aneurysms originating in relation to a mid-basilar dissection, resulting in multiple episodes of SAH. These are difficult and dangerous lesions that can be treated with open microsurgical reconstruction or possibly via an endovascular approach. The intricate location of the lesions poses a particular challenge to neurosurgeons attempting to directly treat mid-basilar lesions.

Background : Primitive trigeminal artery variants (PTAVs) are one of the rare persistent fetal anastomoses between the carotid and vertebrobasilar circulations. They originate from the internal carotid artery and join one of the cerebellar arteries instead of the basilar artery. Case Description : We present an 82-year-old woman with subarachnoid hemorrhage due to a ruptured aneurysm originating at a PTAV. Three-dimensional computed tomography angiogram and cerebral angiography revealed bilateral PTAV and two aneurysms originating at the left PTAV. The proximal and distal aneurysms were saccular and fusiform, respectively. She underwent surgical treatment and her postoperative course was uneventful. Conclusion : Our case demonstrates that extremely rare cerebral aneurysms associated with PTAV can be addressed successfully by surgical intervention.

Background : Trends in management of aneurysmal subarachnoid hemorrhage and unruptured intracranial aneurysms among neurosurgeons is very variable and had not been previously described in any Latin American country. This study was conducted to determine the preferences of Colombian neurosurgeons in pharmacologic, surgical, and endovascular management of patients with aneurysmal subarachnoid hemorrhage and unruptured intracranial aneurysms. Methods : A survey-based descriptive study was performed in a sample of members from the Colombian Association of Neurosurgery. Questions about pharmacologic, surgical, and endovascular management of aneurysmal subarachnoid hemorrhage and unruptured intracranial aneurysm were carried out. We calculated the mean and the standard deviation of the results obtained from the continuous variables. The results of the categorical variables are presented as percentages. Results : The preference of medication with poor clinical evidence, such as magnesium sulfate, aspirin, statins, and anti-fibrinolytics was lower than 10%. The use of intravenous nimodipine and systemic glucocorticoids was as high as 31%. The availability of endovascular therapy was 69%. The indication for treatment of patients with unruptured intracranial aneurysms that required intervention was less than 13.8%. In patients with ruptured or unruptured intracranial aneurysms, coiling was the preferred method for exclusion. Conclusions : Reported compliance of evidence-based clinical guidelines was similar to that described in developed countries, and even better. However, there is little agreement in treating patients with unruptured intracranial aneurysms. For other issues, the conducts reported by Colombian neurosurgeons are in accordance with the current guidelines.

Background : The pterional approach is the most common for AComm aneurysms, but we present a unilateral approach to a midline region for addressing the AComm complex. The pure subfrontal approach eliminates the lateral anatomic dissection requirements without sacrificing exposure. The subfrontal approach is not favored in the US compared to Asia and Europe. We describe our experience with the subfrontal approach for AComm aneurysms treated at a single institution. Methods : We identified 28 patients treated for AComm aneurysms through the subfrontal approach. Patient records and imaging studies were reviewed. Demographics and case data, as well as clinical outcome at 6 weeks and 1 year were collected. Results : Mean patient age was 48 (range 21-75) years and 64% suffered subarachnoid hemorrhage (SAH). All aneurysms were successfully clipped. Gyrus rectus was resected in 57% of cases, more commonly in ruptured cases. Intraoperative rupture occurred in 11% of cases. The average operative time was 171 minutes. There were two patient deaths. Ninety-two percent of patients had a Glasgow Outcome Scale (GOS) of 5 at 6 weeks. All unruptured patients had a GOS of 5. At 12 months, 96% of all patients had a GOS of 5. Conclusions : The subfrontal approach provides an efficient avenue to the AComm region, which reduces opening and closing friction but still yields a comprehensive operative window for access to the anterior communicating region.

Background : Although a relatively simple procedure, cranioplasties have been associated with high complication rates. Keeping this in perspective, we aimed to determine the factors associated with immediate and long-term complications of cranioplasties at our institution. Methods : A retrospective review of patient records was carried out for patients having undergone reconstructive cranioplasties at our institution during the last 10 years (2001-2010). All case notes, records, and investigations were reviewed and the data were recorded in a predesigned questionnaire. Complications were recorded along with existing comorbids and measures taken for their prevention and management. Univariate and multivariate logistic regression analysis was performed to determine possible predictors of complications. Results : A total of 96 patients with a mean age of 33 + 15 years were included in the study. Of the sample, 76% (n = 73) had no comorbids. The leading primary pathology was blunt traumatic brain injuries in 46% (n = 44), followed by cerebrovascular incidents in 24% (n = 23), penetrating traumatic brain injuries in 12% (n = 11), and tumors in 10% (n = 10) of cases, with 41% (n = 39) of patients requiring multiple craniotomies. In a mean follow-up of 386 ± 615 days, complications were noted in 36.5% (n = 35) of the patients. Twenty six percent of patients (n = 25) had minor complications which included breakthrough seizures (15.6%, n = 15), subgaleal collections (3.1%, n = 3), and superficial wound infections (3.1%, n = 3), whereas major complications (10.4% n = 10) included hydrocephalus (3.1%, n = 3), transient neurological deficits (3.1%, n = 3), and osteomyelitis (2.1%, n = 2). Univariate and multivariate analysis revealed External Ventricular Drain (EVD) placement and parietal flaps to be associated with complications. This could be explained by the fact that the patients requiring EVD usually have relatively severe head injuries, increasing the possibility of hydrocephalus. Conclusion : We have found a higher risk of complications of cranioplasty in patients who had EVD placement and removal prior to their constructive surgery. We however did not find any association between risks of complications in any other studied variable. We also did not find any association between intraoperative placement of subgaleal drains and postoperative risk of subgaleal fluid collections. Overall, our results are comparable with other reported series on cranioplasties.

Background: The use of force to control public uprisings, riots, unruly mobs is an important tool in any administrative setup. Law enforcement agencies often resort to aerial firing, which can be responsible for unintended injuries due to stray bullets.This study was designed to study the pattern of stray bullet injuries and to generate awareness about the hazards related to the use of live ammunition during riot control. Methods: This study was conducted in our unit of the neurosurgery department over a period of 18 months, from June 2008 to December 2010. We enrolled all patients who had head or spine injuries caused by stray bullets from firing during riot control far away from the site of injury. Results: We had two patients with head injury and two with spinal injury sustained because of stray bullets. One of the patients with head injury was operated and the other one was managed conservatively; the latter died on the third day of injury, while the former is surviving with some residual neurological deficit. Amongst the patients with spinal injury, neurological deficits persist till date. None of the patients were aware that they had sustained a bullet injury, and it was only after inquiry that we came to know that the police had resorted to aerial firing for controlling public agitation in nearby areas. Conclusion: Aerial firing of live cartridges is generally considered an 'innocuous' method; however, in view of the potential for injury to innocent bystanders, we recommend that the use of live cartridges during aerial firing be banned.

Background: The recovery of hand function is consistently rated as the highest priority for persons with tetraplegia. Recovering even partial arm and hand function can have an enormous impact on independence and quality of life of an individual. Currently, tendon transfers are the accepted modality for improving hand function. In this procedure, the distal end of a functional muscle is cut and reattached at the insertion site of a nonfunctional muscle. The tendon transfer sacrifices the function at a lesser location to provide function at a more important location. Nerve transfers are conceptually similar to tendon transfers and involve cutting and connecting a healthy but less critical nerve to a more important but paralyzed nerve to restore its function. Methods: We present a case of a 28-year-old patient with a C5-level ASIA B (international classification level 1) injury who underwent nerve transfers to restore arm and hand function. Intact peripheral innervation was confirmed in the paralyzed muscle groups corresponding to finger flexors and extensors, wrist flexors and extensors, and triceps bilaterally. Volitional control and good strength were present in the biceps and brachialis muscles, the deltoid, and the trapezius. The patient underwent nerve transfers to restore finger flexion and extension, wrist flexion and extension, and elbow extension. Intraoperative motor-evoked potentials and direct nerve stimulation were used to identify donor and recipient nerve branches. Results: The patient tolerated the procedure well, with a preserved function in both elbow flexion and shoulder abduction. Conclusions: Nerve transfers are a technically feasible means of restoring the upper extremity function in tetraplegia in cases that may not be amenable to tendon transfers.

Background: Calcified chronic subdural hematomas occur infrequently. When the calcifications are extensive and bilateral, the condition is termed "armored brain". We describe a case of "armored brain" incidentally discovered in an adult presenting with abdominal pain and mild headaches, long after initial placement of a ventriculo-peritoneal (VP) shunt. Case Description: A 38-year-old woman, treated at infancy with a VP shunt, presented with a 2-month history of abdominal pain associated with nausea and chills. She was neurologically intact on exam. An abdominal computed tomography (CT) scan demonstrated a rim-enhancing loculated fluid collection surrounding the patient's distal VP shunt catheter tip. As a part of her initial work-up, she received a head CT to evaluate the proximal VP shunt, which demonstrated large bilateral chronic subdural hematomas with heavily calcified walls. She was eventually taken to the operating room (OR) for replacement of the distal catheter. It was felt that her acute clinical presentation was unrelated to the bilateral, calcified subdural hematomas and thus the decision was made to manage them conservatively. Conclusions: This rare complication of chronic shunting for hydrocephalus is sometimes referred to as armored brain. Surgery for armored brain is infrequently indicated and beneficial in only small subgroup of patients, with management guided by clinical presentation. Our patient fully recovered after shunt revision alone.

Background: There have been 18 reported cases of primary spinal intradural, extramedullary ependymomas reported in the literature. One of the 18 cases had an extradural component and was benign. Our case is the second spinal intradural, extramedullary ependymoma with an extradural component and the first with its initial presentation as an anaplastic ependymoma. Case Description: A 50-year-old male presented with bilateral upper thigh weakness and thoracic numbness. His exam showed the pin-prick level at T5. Magnetic resonance imaging (MRI) of the thoracic spine showed an enhancing lesion at T5-6 with severe compression of the spinal cord with a dumbbell shape extension of the tumor through the right T5-6 neural foramen. The patient had a laminectomy at T4-T6 with the resection of the tumor. Postoperatively, the patient regained full strength in his lower extremities. Intraoperatively, the tumor was found to be intradural, extramedullary with an extradural component. The tumor was found to be an anaplastic ependymoma. Conclusions: Even though spinal intradural extramedullary ependymomas are very rare, surgeons must be aware that on MRI, they can be mistaken for meningiomas or nerve sheath tumors especially if there is an extradural component. Our case report is the first intradural, extramedullary ependymoma that is anaplastic and has an extradural component. A review of the literature provides little information on the treatment and prognosis for these tumors especially if they are anaplastic. We propose that the treatment, as done in our case, should be complete resection of the tumor with spinal radiotherapy to the tumor level.

Background: Intracranial osteochondromas are uncommon. The majority of lesions arise from the base of the skull or from bones developed by endochondral ossification. A minority of cases are attached to the falxcerebri in the fronto parietal location. Case Description: We report a case of a giant intracranial osteochondroma in a 24-year-old man. This patient presented with complaints of convulsions and headache. Imaging studies of the brain, gross, and histological features concluded it to be an osteochondroma. Conclusion: This case is reported in view of extreme rarity of the lesion, and to emphasize the fact that complete surgical resection is curative.

Background: Acute hydrocephalus (HCP) after aneurysmal subarachnoid hemorrhage (SAH) often persists. Our previous study described factors that singly and combined in a formula correlate with permanent CSF diversion. We now aimed to determine whether the same parameters are applicable at an institution with different HCP management practice. Methods: We reviewed records of 181 consecutive patients who presented with SAH and received an external ventricular drain (EVD) for acute HCP. After exclusion and inclusion criteria were met, 71 patients were analyzed. Data included admission Fisher and Hunt and Hess grades, aneurysm location, treatment modality, ventricle size, CSF cell counts and protein levels, length of stay (LOS) in the hospital, and the presence of craniectomy. Outcome measures were: (1) initial EVD challenge outcome; (2) shunting within 3 months; and (3) LOS. Results: Shunting correlated with Hunt and Hess grade, CSF protein, and the presence of craniectomy. The formula derived in our previous study demonstrated a weaker correlation with initial EVD challenge failure. Several parameters that correlated with shunting in the previous study were instead associated with LOS in this study. Conclusions: The decision to shunt depends on management choices in the context of a disease process that may improve over time. Based on the treatment strategy, the shunting rate may be lowered but LOS increased. Markers of disease severity in patients with HCP after SAH correlate with both shunt placement and LOS. This is the first study to directly evaluate the effect of different practice styles on the shunting rate. Differences in HCP management practices should inform the design of prospective studies.

Background : Spindle cell oncocytoma (SCO) and pituicytoma are rare nonfunctioning tumors of the pituitary. Both tumors are low grade and macroscopically indistinguishable from a nonfunctioning pituitary adenoma.We report one case of SCO and one case of pituicytoma and review the previous literature. Case Description : One patient was a 39-year-old man who presented with progressive headache, visual blurring, and polyuria of 3-year duration. He underwent partial resection (30% of the tumor) and postoperative adjuvant radiation therapy. Histopathology revealed SCO. However, after 9 months, the residual tumor grew and partial resection (70% of the tumor) was performed again. Four months after the second surgery, the tumor recurred again and he underwent transsphenoidal resection of the tumor with stable residual tumor to date. The other patient was a 59-year-old man who presented with a 3-month history of visual decline, fatigue, difficulty in writing, and polyuria. He underwent transsphenoidal resection (total) of the tumor. Histopathology revealed pituicytoma. He has been stable without evidence of recurrence for 1 year and 4 months. Conclusion : To date, there are 15 reported cases of SCO and 45 reported cases of pituicytoma including our cases. An incomplete resection of the tumor was a significant risk factor for recurrence in both SCO and pituicytoma (P = 0.0014 and P = 0.019, respectively). These tumors have a tendency to be hypervascular, which may hamper total resection. Epithelial membrane antigen (EMA) and mitochondria positivity is characteristic to SCO and they are considered to be important immunomarkers to distinguish these tumors.

Background : INFUSE, bone morphogenetic protein-2 combined with bovine Type I collagen in the lumbar tapered fusion device (LT Cage), is used to promote anterior lumbar interbody fusion (ALIF). In spinal surgery, INFUSE is only Federal Drug Administration (FDA) approved for this "on-label" use. While the efficacy and possible complications due to INFUSE have been debated, we know less about the costs and frequency of "on-label" versus "off-label" use of INFUSE to perform spinal fusions. Methods : At one institution, we determined the costs (with overhead) and frequency of utilizing INFUSE "on-label" and "off-label" in performing spinal fusions during 2010. Results : During 2010, 177 spinal fusions utilized INFUSE. Ninety-six percent, or 170 of 177 spinal fusions, utilized INFUSE in an "off-label" capacity at a cost of $4,547,822. Only 4%, or seven of 177 cases, utilized INFUSE in an "on-label" capacity (ALIF); the total cost was $296,419. Conclusions : In 2010, at one institution, 96% of the spinal fusions utilized INFUSE in an "off-label" capacity (cost $4,547,822), while only 4% were performed "on-label" (cost $296,4194).

Background: It is almost an accepted scenario that trigeminal neuralgia (TN) occurs when there is a kind of vascular compression on the root entry zone of trigeminal nerve at pons. There are occasional reports about trigeminal neuralgia as the presenting sign of intracranial tumors but temporal glioma has rarely been included in the list. Case Description: We report three cases of temporal lobe glioma which presented with trigeminal neuralgia as the initial manifestation and review the relevant literature briefly. The patients were 19-, 20-, and 31-year-old males who presented with partially controlled TN. The tumor mass could be detected in paraclinical evaluations when the usual modalities of therapy for facial pain in our community were not effective. Excisional surgery led in full pain control in all the cases. Two of the patients died because of tumor recurrence after a year and the other one is being treated by adjuvants. Conclusion: We add these types of intracranial tumors to the list of the etiologies for TN and the possible mechanisms for the initiation of pain in these types of intracranial tumors are discussed.

Background: Most of the time meningiomas are benign brain tumors and surgical removal ensures cure in the vast majority of the cases. Thus, whenever possible, complete surgical resection should be the goal of the treatment. Methods: This is a report of our surgical technique for the operative resection of a trigonal meningioma in a resource-limited setting. The necessity of accurate and deep knowledge of the regional anatomy is outlined. Results: A 44-year-old male presented to our outpatient clinic complaining of cephalalgia increasing in frequency and intensity over the last month. His neurological exam was normal, yet a brain computed tomography scan revealed a lesion in the right trigone of the ventricular system. The diagnosis of possible meningioma was set. After thoroughly informing the patient, tumor resection was decided. An intraparietal sulcus approach was favored without the use of any modern technological aids such as intraoperative magnetic resonance imaging or neuronavigation. The postoperative course was uneventful and a postoperative computed tomography scan demonstrated the complete resection of the tumor. The patient was discharged two days later with no neurological deficits. In a two-year-follow-up he remains recurrence-free. Conclusion: In the current cost-effective era it is still possible to safely remove an intraventricular trigonal meningioma without the convenience of neuronavigation. Since the best neuronavigator is the profound neuroanatomical knowledge, no technological advancement could replace a well-educated and trained neurosurgeon.

Background: Glial scar (GS) is the most important inhibitor factor to neuroregeneration after spinal cord injury (SCI) and behaves as a tertiary lesion. The present review of the literature searched for representative studies concerning GS and therapeutic strategies to neuroregeneration. Methods: The author used the PubMed database and Google scholar to search articles published in the last 20 years. Key words used were SCI, spinal cord (SC) inflammation, GS, and SCI treatment. Results: Both inflammation and GS are considered important events after SCI. Despite the fact that firstly they seem to cause benefit, in the end they cause more harm than good to neuroregeneration. Each stage has its own aspects under the influence of the immune system causing inflammation, from the primary to secondary lesion and from those to GS (tertiary lesion). Conclusion: Future studies should stress the key points where and when GS presents itself as an inhibitory factor to neuroregeneration. Considering GS as an important event after SCI, the author defends GS as being a tertiary lesion. Current strategies are presented with emphasis on stem cells and drug therapy. A better understanding will permit the development of a therapeutic basis in the treatment of the SCI patients considering each stage of the lesion, with emphasis on GS and neuroregeneration.

Background: Intraoperative transcranial motor-evoked potential (TCMEP) monitoring is widely performed during neurosurgical operations. Sensitivity and specificity in TCMEP during neurosurgical operations were examined according to the type of operation. Methods: TCMEP monitoring was performed during 283 neurosurgical operations for patients without preoperative motor palsy, including 121 spinal operations, 84 cerebral aneurysmal operations, and 31 brain tumor operations. Transcranial stimulation at 100-600 V was applied by screw electrodes placed in the scalp and electromyographic responses were recorded with surface electrodes placed on the affected muscles. To exclude the effects of muscle relaxants on TCMEP, compound muscle action potential (CMAP) by supramaximal stimulation of the peripheral nerve immediately after transcranial stimulation was used for compensation of TCMEP. Results: In spinal operations, with an 80% reduction in amplitude as the threshold for motor palsy, the sensitivity and specificity with CMAP compensation were 100% and 96.4%, respectively. In aneurysmal operations, with a 70% reduction in amplitude as the threshold for motor palsy, the sensitivity and specificity with CMAP compensation were 100% and 94.8%, respectively. Compensation by CMAP was especially useful in aneurysmal operations. In all neurosurgical operations, with a 70% reduction in amplitude as the threshold for motor palsy, the sensitivity and specificity with CMAP compensation were 95.0% and 90.9%, respectively. Conclusions: Intraoperative TCMEP monitoring is a significantly reliable method for preventing postoperative motor palsy in both cranial and spinal surgery. A 70% reduction in the compensated amplitude is considered to be a suitable alarm point in all neurological operations.

Background: To better understand the longitudinal trend in the proportion of techniques employed for cerebral aneurysm treatment, we reviewed our experience with 2253 patients over the last 11 years. Methods: We reviewed data in our prospective aneurysm database for all consecutive patients treated from January 1998 through December 2009. Data regarding age, sex, aneurysm location, presence or absence of hemorrhage, Fisher grade, clinical grade, treatment methods, length of hospitalization, and mortality rates by the time of discharge were retrieved and retrospectively analyzed. The most common aneurysm types were subsequently classified and analyzed separately. Results: The patient population included 663 males (29%) and 1590 females (71%). A total of 2253 patients presented with 3413 aneurysms; 1523 (63%) of the aneurysms were diagnosed as aneurysmal subarachnoid hemorrhage. A total of 2411 (71%) aneurysms were treated. Overall, 645 (27%) of the 2411 aneurysms underwent endosaccular coiling and 1766 (73%) underwent clip ligation; 69 (3%) of these aneurysms required both treatment modalities. The percentage of all aneurysms treated by endosaccular coiling increased from 8% (21) in 1998 to 28% (87) in 2009. There was no statistical difference between the average length of hospitalization for patients who underwent endosaccular coiling and clip ligation for their ruptured (P = 0.19) and unruptured (P = 0.80) aneurysms during this time period. Conclusions: In our practice, endovascular treatment has continued to be more frequently employed to treat cerebral aneurysms. This technique has had the greatest proportional increase in the treatment of posterior circulation aneurysms.

Background: Many studies offer excellent demonstration of the ability of bone morphogenic protein (BMP) to enhance fusion rates in anterior as well as posterior lumbar surgery. Recently, BMP has also been shown to increase arthrodesis rates in anterior cervical surgery, albeit with concomitant increases in complication rates. To date, however, few studies have investigated the safety and efficacy of BMP in cervical surgeries approached posteriorly. Methods: We retrospectively reviewed 204 consecutive patients with degenerative cervical spinal conditions necessitating posterior cervical fusion at a single institution over the past 4 years. The incidence of postoperative mechanical neck pain, fusion rates, as well as neurologic outcomes were compared between patients who received BMP vs those who did not receive BMP intraoperatively. Results: There were no significant differences in preoperative variables between the non-BMP vs the BMP cohorts. Over an average follow-up of 24.2 months, there were no significant differences between the two cohorts in duration of hospitalization, cerebrospinal fluid leakage, deep vein thrombosis, pulmonary embolism, hyperostosis, infection, pneumonia, hematoma, C5 palsy, wound dehiscence, reoperation rates, or Nurick/ASIA scores. Eleven (7.1%) patients in the non-BMP group experienced instrumentation failure vs none in the BMP group (P=0.06). Patients receiving BMP had a significantly increased rate of fusion by the chi-square test (P=0.01) and the log-rank test (P=0.02). However, patients receiving BMP also had the highest rates of recurrent/persistent neck pain by the chi-square test (P=0.003) and the log-rank test (P=0.01). Conclusions: To date, few studies have evaluated the safety and efficacy of BMP in the posterior cervical spine. Here, we show that BMP usage does not increase complication rates, but it significantly increases arthrodesis rates and also may increase the rate of recurrent/persistent neck pain.

Some individuals suffering from mild traumatic brain injuries, especially repetitive mild concussions, are thought to develop a slowly progressive encephalopathy characterized by a number of the neuropathological elements shared with various neurodegenerative diseases. A central pathological mechanism explaining the development of progressive neurodegeneration in this subset of individuals has not been elucidated. Yet, a large number of studies indicate that a process called immunoexcitotoxicity may be playing a central role in many neurodegenerative diseases including chronic traumatic encephalopathy (CTE). The term immunoexcitotoxicity was first coined by the lead author to explain the evolving pathological and neurodevelopmental changes in autism and the Gulf War Syndrome, but it can be applied to a number of neurodegenerative disorders. The interaction between immune receptors within the central nervous system (CNS) and excitatory glutamate receptors trigger a series of events, such as extensive reactive oxygen species/reactive nitrogen species generation, accumulation of lipid peroxidation products, and prostaglandin activation, which then leads to dendritic retraction, synaptic injury, damage to microtubules, and mitochondrial suppression. In this paper, we discuss the mechanism of immunoexcitotoxicity and its link to each of the pathophysiological and neurochemical events previously described with CTE, with special emphasis on the observed accumulation of hyperphosphorylated tau.

Background : To evaluate the changes in brain metabolites by H1 magnetic resonance spectroscopy in two patients with electrical status epilepticus. Case Description : Two boys (aged 6 and 7 years) with electrical status epilepticus in sleep have been evaluated. N-acetyl aspartate levels were slightly elevated, and showed no decline in the postictal period. Creatine and choline levels were similar to that in controls. No evidence of neuronal cell damage was seen. Conclusion : Electrical status epilepticus is a balanced condition of hypermetabolism, when not accompanied with seizure.

Background : Our aim was to identify the preoperative factors associated with a greater risk of poor inpatient outcomes in those undergoing resection of hypothalamic hamartomas. Methods : We performed a multi-institutional retrospective cohort analysis via the Nationwide Inpatient Sample (1998 - 2007). Patients of any age who underwent resection of hypothalamic hamartomas were identified by ICD-9 coding. The primary outcomes included inpatient complications, length of stay (LOS), and total charges. Multivariate regression models were constructed to analyze the outcomes. Results : Two hundred and eighty-two patients were identified with a mean age of 27.7 years, with most being male (53.2%), Caucasian (78.9%), privately insured (69.3%), and treated electively (74.7%) at academic centers (91.7%). A majority (82.2%) had Elixhauser comorbidity scores of < 1, indicating few comorbidities. No inpatient deaths were reported. Mean LOS was 7.39 days and the mean total hospital charges were $53,935. Overall, 19.5% developed an inpatient complication, primarily stroke (16.7%). Female gender, ethnic / racial minorities, higher comorbidity scores, private insurance, and non-academic hospitals were associated with greater LOS and total charges. Private insurance (Odds Ratio, OR: 1.59, P = 0.045) and academic hospitals (OR: 1.43, P = 0.008) were associated with significantly higher odds of any complication. Minority race / ethnicity was associated with a minimal increase in the odds of postoperative stroke (OR: 1.02, P < 0.001) relative to Caucasians. Conclusions : Through an analysis of a 10-year multi-institutional database, we have described the surgical outcomes of patients undergoing resection of hypothalamic hamartomas. Results demonstrate significant inpatient morbidity, particularly postoperative stroke. Patient- and institution-level factors should be considered in determining the perioperative risk for such patients.

Background: Myelopathy from ectatic vertebral artery compression of the spinal cord at the cervicomedullary junction is a rare condition. Case Description: A 63-year-old female was originally diagnosed with occult hydrocephalus syndrome after presenting with symptoms of ataxia and urinary incontinence. Ventriculoperitoneal shunting induced an acute worsening of the patient's symptoms as she immediately developed a sensory myelopathy. An MR scan demonstrated multiple congenital abnormalities including cervicomedullary stenosis with anomalous vertebral artery compression of the dorsal spinal cord at the cervicomedullary junction. The patient was taken to surgery for a suboccipital craniectomy, C1-2 laminectomy, vertebral artery decompression, duraplasty, and shunt ligation. Intraoperative findings confirmed preoperative radiography with ectactic vertebral arteries deforming the dorsal aspect of the spinal cord. There were no procedural complications and at a 6-month follow-up appointment, the patient had experienced a marked improvement in her preoperative signs and symptoms. Conclusion: Myelopathy from ectatic vertebral artery compression at the cervicomedullary junction is a rare disorder amenable to operative neurovascular decompression.

Background: In recent years, distal nerve transfers have become a valid tool for nerve reconstruction. Though grafts remain the gold standard for proximal median nerve injuries, a new distal transfer of flexor carpi ulnaris branches of the ulnar nerve to selectively restore anterior interosseous nerve function, concomitant with median nerve graft repair, could enhance outcomes. The objective of this paper is to anatomically analyze a technique to selectively reinnervate the thumb and index flexors. Methods: Both the median and ulnar nerves were dissected in 10 cadavers. First and second branches to the flexor carpi ulnaris (FCU) were measured for length at its emergence from the ulnar nerve, and for width. The emergence of the AIN, just proximal to the arch of the flexor digitorum superficialis, was dissected, and the distance measured from this point to its motor entry at the long flexor pollicis and its branch to the long index flexor. A tensionless repair was performed between one FCU branch and the AIN. Results: The mean AIN length was 32.3±8.20 mm and width 2.4±0.49 mm. The first branch from the ulnar nerve to the FCU measured 20.8±2.04 mm and 1.52±0.44 mm, while the second, more distal branch measured 24.3±6.71 and 1.9±0.17 mm, respectively. In all dissections, it was possible to contact both the proximal and distal branches of the ulnar nerve to the FCU with the distal stump of the divided AIN, with no tension or need for interposed nerve grafts. Conclusions: Though proximal reconstruction remains the gold standard, new distal nerve transfer techniques may improve outcomes.

Background: Tectal plate tumors have traditionally been considered low-grade, indolent lesions. We report a patient who presented with a tectal region glioblastoma multiforme (GBM), a rare pathology in this anatomic location. Case Description: This is a case report of a 45-year-old female that presented with worsening confusion, memory loss, and loss of bladder control for 3 days. There was no family history of brain malignancy. The patient presented with Parinaud's phenomenon. Pronator drift was not present. The patient had dysarthric speech. An elevated white blood cell count was also noted. Non-contrast CT scan of the head showed the presence of a tectal region mass and hydrocephalus. A follow-up MRI with and without contrast confirmed the presence of a 4.2 × 3.3 × 4.6 cm ³ mass. Magnetic Resonance Spectroscopy (MRS) demonstrated an elevated choline/N-acetylaspartate ratio and an increase in lactate suggesting an aggressive neoplasm. A ventriculoperitoneal shunt was initially placed to relieve the hydrocephalus. The patient subsequently underwent a suboccipital craniotomy for debulking of tumor and for tissue diagnosis. Pathology of the lesion was consistent with GBM. The patient declined postoperative treatment with chemotherapy and radiation. Conclusion: Although tectal region masses are predominantly low-grade lesions, high-grade lesions can present in this anatomical location. Furthermore, MRS can help to differentiate benign lesions from more aggressive lesions in the tectal plate. Biopsy of tectal plate lesions should be considered in select cases to establish diagnosis and prognosis in order to optimize treatment.

Background: Double-injection models of subarachnoid hemorrhage (SAH) in rats are the most effective in producing vasospasm, delayed neurological deficits and infarctions. However, they require two large surgeries to expose the femoral artery and the atlanto-occipital membrane. We have developed a minimally-invasive modification that prevents confounding effects of surgical procedures, leakage of blood from the subarachnoid space and minimizes risk of infection. Methods: Rats are anesthetized and the ventral tail artery is exposed through a small (5 mm), midline incision, 0.2 mL of blood is taken from the artery and gentle pressure is applied for hemostasis. The rat is flipped prone, and with the head flexed to 90 degrees in a stereotactic frame, a 27G angiocath is advanced in a vertical trajectory, level with the external auditory canals. Upon puncturing the atlanto-occipital membrane, the needle is slowly advanced and observed for cerebrospinal fluid (CSF). A syringe withdraws 0.1 mL of CSF and the blood is injected into the subarachnoid space. The procedure is repeated 24 hours later by re-opening the tail incision. At 8 days, the rats are euthanized and their brains harvested, sectioned, and incubated with triphenyltetrazolium chloride (TTC). Results: Rats develop neurological deficits consistent with vasospasm and infarction as previously described in double-injection models. Cortical and deep infarctions were demonstrated by TTC staining and on histopathology. Conclusions: A minimally invasive, double-injection rat model of SAH and vasospasm is feasible and produces neurological deficits and infarction. This model can be used to study neuroprotective treatments for vasospasm and delayed neurological deficits following SAH, reducing the confounding effects of surgical interventions.

Background: To describe the use of a short segment cortical intracranial-intracranial (IC-IC) bypass for the treatment of a distal middle cerebral artery (MCA) aneurysm. Case Description: A 54-year-old woman presented with a loss of consciousness followed by multiple seizures and was found to have a partially thrombosed distal MCA aneurysm. This possibly mycotic aneurysm was treated by creating a short segment jump graft between a normal cortical artery and a nearby cortical branch arising from the aneurysmal M3 arterial segment. The bypass allowed for subsequent occlusion of the aneurysmal vessel without ischemic consequence. At surgery, the anterior division of the superficial temporal artery (STA) was exposed and dissected. Intraoperative angiography was utilized to localize a cortical artery arising from the involved segment as well as a nearby cortical artery arising from a distinct, uninvolved MCA branch. A segment of the STA was harvested, and then 10-0 suture was utilized to anastomose this short segment, to both the involved and normal cortical arteries. This created a short jump graft allowing for subsequent sacrifice of the diseased artery. Following surgery, the patient immediately underwent coil embolization of the aneurysm back into the parent artery resulting in local vascular sacrifice. The remainder of the patient's hospital course was uneventful. She was discharged home in good condition. Conclusions: We suggest that cortical IC-IC bypass followed by endovascular arterial sacrifice as performed in our case represents a simple and safe option for treating unclippable distal MCA aneurysms including mycotic lesions.

Background: The spinal dura is anchored within the vertebral canal by connective tissue in the epidural space as well as the spinal roots. Inadvertent disruption of these dural attachments may lead to durotomy and cerebrospinal fluid (CSF) leaks. We observed well-developed connective tissue ligaments connecting the lumbar dura to the spinal column and examined these tissues microscopically. Methods: Intraoperative images were obtained during lumbar laminectomy procedures. They demonstrated connective tissue attachments, linking the lumbar dura to the spinal column in the dorsal midline and dorsolaterally. Tissue samples were obtained and examined microscopically. We then conducted a search of the literature to find references to dural attachments to the spinal column. Results: Histological examination of the samples showed minimal cellular fibrous tissue. To date no references to these attachments have been made in neurosurgical literature. Previous studies, including live, cadaveric, and radiographic examinations, have demonstrated a dorsomedian fold of dura attached to the junction of the ligamentum flavum, and dorsolateral ligaments that divide the dorsal epidural space into an anterior and posterior compartment. Conclusions: Epidural fibrous connections or ligaments between the dura and the lumbar spinal column may be of clinical importance to the neurosurgeon. Care should be taken during lumbar procedures not to disrupt or tear these ligaments as this may cause dural tears and CSF leaks. Identifying these ligaments and cutting them sharply may prevent inadvertent durotomies.

Background: Cauda equina paragangliomas (CEP) are rare tumors. Low back pain and sciatica are the main presenting symptoms. Magnetic resonance imaging (MRI) is the study of choice and treatment consists of total excision when feasible. Definitive diagnosis can only be made after immunohistochemical investigation. CEP is classified as grade I WHO and after total removal the prognosis is excellent. Nonetheless, after subtotal removal, tumor recurrence can occur. Case Description: We present 3 cases of CEP, preoperatively diagnosed as an intradural mass on MRI and suspected to be ependymoma. All 3 patients presented with low back pain and variable sciatic pain. Total resection of the tumor was performed after which all patients fully recovered. There is no recurrence after 13, 11, and 5 years, respectively. Conclusion: CEP is a rare tumor. We diagnosed 3 paragangliomas out of a series of 105 intradural extramedullary tumors in adults (1994-2005). No recurrence was seen after total resection. In retrospect, both the intraoperative appearance and the MR image were not completely typical for schwannoma or ependymoma, but final diagnosis can only be made histologically.

Background: Aneurysms of the anterior inferior cerebellar artery (AICA), especially those located in the distal portion of the AICA, are rare. There are few reported cases treated with surgery or endovascular embolization. Case Description: We report two cases of fusiform distal AICA aneurysms presenting with subarachnoid hemorrhage. Parent artery occlusion with coils and n-butyl cyanoacrilate (n-BCA) resulted in complete aneurysm occlusion and prevented rebleeding. Both patients presented postprocedure neurological deficits, but have made a good recovery at 4 and 10 months, respectively. Conclusion: Occlusion of the parent artery for the treatment of ruptured fusiform distal AICA aneurysms is effective but has significant neurological risks.

Background: A major purported benefit of minimally-invasive spinal surgery (MIS) technique is less disruption of paraspinal soft tissues, but there is little quantifiable evidence of this in medical literature. Postoperative C-reactive protein (CRP) levels been shown to become more significantly elevated with larger surgical procedures, and this may allow for more measurable appreciation of any benefits of MIS verses open spinal surgery. Methods: CRP values were measured prior to and at multiple time points following surgery in patients undergoing posterior spinal fusion using both open and minimally invasive techniques. Results: Peak postoperative CRP was significantly lower in the 35 single-level minimally invasive procedures compared with the 11 single-level open procedures (13.5 vs. 21.3, p <0.01) and lower in the 12 two-level minimally invasive surgeries compared with 16 two-level open procedures (20.5 vs. 31.8, p <0.01). Conclusions: MIS lumbar fusion is associated with a lower peak in postoperative CRP compared with open surgery. This appears to support the notion that minimally invasive spine surgery technique leads to a measurable reduction in paraspinal soft tissue destruction mediated inflammation in the immediate postoperative period.

Background: Open discectomy remains the standard method for treatment of lumbar disc herniation, but can traumatize spinal structure and leaves symptomatic epidural scarring in more than 10% of cases. The usual transforaminal approach may be associated with difficulty reaching the epidural space due to anatomical peculiarities at the L5-S1 level. The endoscopic interlaminar approach can provide a direct pathway for decompression of disc herniation at the L5-S1 level. This study aimed to evaluate the clinical results of endoscopic interlaminar lumbar discectomy at the L5-S1 level and compare the technique feasibility, safety, and efficacy under local and general anesthesia (LA and GA, respectively). Methods: One hundred twenty-three patients with L5-S1 disc herniation underwent endoscopic interlaminar lumbar discectomy from October 2006 to June 2009 by two spine surgeons using different anesthesia preferences in two medical centers. Visual analog scale (VAS) scores for back pain and leg pain and Oswestry Disability Index (ODI) sores were recorded preoperatively, and at 3, 6, and 12 months postoperatively. Results were compared to evaluate the technique feasibility, safety, and efficacy under LA and GA. Results: VAS scores for back pain and leg pain and ODI revealed statistically significant improvement when they were compared with preoperative values. Mean hospital stay was statistically shorter in the LA group. Complications included one case of dural tear with rootlet injury and three cases of recurrence within 1 month who subsequently required open surgery or endoscopic interlaminar lumbar discectomy. There were no medical or infectious complications in either group. Conclusion: Disc herniation at the L5-S1 level can be adequately treated endoscopically with an interlaminar approach. GA and LA are both effective for this procedure. However, LA is better than GA in our opinion.

Background: Isolated intraventricular hemorrhage (IVH) secondary to lenticulostriate artery aneurysm rupture is extremely rare. Thus, the diagnostic imaging modalities and therapeutic interventions utilized in the management of such cases are not clearly defined. Case Description: Here we describe a case of isolated or primary IVH (PIVH) in a 71-year-old woman presenting with severe headache. Emergent catheter cerebral angiography, performed after nondiagnostic computed tomography angiography (CTA), revealed the bleeding source to be a 4 × 2.6 mm distal medial lenticulostriate artery aneurysm that ruptured directly into the lateral ventricle. The poorly accessible location of the aneurysm for both endovascular and direct surgical treatment argued for conservative management. A good clinical outcome was obtained with rapid angiographic resolution of the ruptured aneurysm. Conclusion: Thus, lenticulostriate artery aneurysm rupture must be given diagnostic consideration in cases of isolated IVH. Emergent catheter cerebral angiography should be performed in cases such as this when noninvasive imaging is unrevealing. Conservative management may be a reasonable therapeutic option in patients with this kind of aneurysm, and spontaneous resolution can be observed.

Background: The diencephalic leaf of the Liliequist's membrane is a continuous structure that should be perforated in the endoscopic third ventriculostomy. Its lateral borders are penetrated by the third cranial nerve and the posterior communicating arteries. The most important complication of endoscopic third ventriculostomy is the vascular injury, such as the posterior communicating artery. The purpose of this study is to measure the distance between posterior communicating arteries located below the third ventricle floor and anterior of the mammillary bodies. Methods: In this observational prospective study 20 fresh brains from cadavers were utilized to measure the distance between the posterior communicating arteries in April 2008 at the Death Check Unit of our Institution. A digital photograph of the posterior communicating arteries was taken and the distance between the arteries was measured. The measurement was analyzed using descriptive statistics. Results: In the descriptive analysis of the 20 specimens, the posterior communicating arteries distance was 9 to 18.9 mm, a mean of 12.5 mm, median of 12.2 mm, standard deviation of 2.3 mm. Conclusion: The detailed knowledge of vascular structures involved in the endoscopic third ventriculostomy as to the posterior communicating arteries distance provides a safe lateral vascular border when performing such procedure.

Background: There is a considerable variety of management practices for nontraumatic subarachnoid hemorrhage (ntSAH) across high-volume centers in the Unite