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The abrupt occurrence of a devastating stroke has been referred to as "super death." It has long been realized that ischemic cerebral vascular disease may become symptomatic with a wide variety of clinical patterns. A robust circle of Willis has been recognized for its major protective function in many cases. When it became possible to actually create new collateral circulation to the brain by microsurgical techniques, significant enthusiasm arose. This enthusiasm was interrupted by the negative results of the international randomized trial. Further analysis of the trial raised serious questions regarding incomplete randomization by contributors to the study, and there remains uncertainty about important potential benefits for some individuals. Long-term follow-up of 3 patients having different and complex circumstances is described to emphasize this concern. After the creation of reliable collateral circulation to the brain, none has experienced new ischemic deficit during the subsequent follow-up of 27, 25, and 12 years, respectively. [ABSTRACT FROM AUTHOR]

Objectives: Large meningiomas of the cerebellopontine angle present a formidable surgical challenge due to tumor vascularity, neural attachment, and brain stem compression. The purpose of this paper is to present our use of the combined transtemporal approach in the surgical treatment of 29 large meningiomas. Study Design and Setting: Twenty-nine patients with large meningiomas of the CPA were surgically treated through a combined retrosigmoid-transpetrosal-transcochlear approach at our tertiary care academic medical center from July 1995 through July 2004. Data was collected from a retrospective medical records review. Results: Total tumor removal was achieved in 19 of 29 (67%) of the patients and the facial nerve was anatomically preserved in 26 of 29 (89%) of the cases. Cerebrospinal fluid leakage was seen in 3.5% of the patients and additional transient cranial nerve deficits were noted in 14% of the cases, but no significant neurologic sequelae occurred. Of the 10 patients with residual tumor, 6 have been stable without growth, 2 were treated with reoperation for regrowth of disease, and 2 were controlled with localized radiotherapy. Conclusions: This combined lateral transtemporal approach provided wide exposure to the cerebellopontine angle and optimized the surgical extirpation of 29 large meningiomas presented in this series. Ebm Rating: C-4. [ABSTRACT FROM AUTHOR]

The purpose of this report is to chronicle a 2-decade period of educational innovation and improvement, as well as governance reform, across the specialty of neurological surgery. Neurological surgery educational and professional governance systems have evolved substantially over the past 2 decades with the goal of improving training outcomes, patient safety, and the quality of US neurosurgical care. Innovations during this period have included the following: creating a consensus national curriculum; standardizing the length and structure of neurosurgical training; introducing educational outcomes milestones and required case minimums; establishing national skills, safety, and professionalism courses; systematically accrediting subspecialty fellowships; expanding professional development for educators; promoting training in research; and coordinating policy and strategy through the cooperation of national stakeholder organizations. A series of education summits held between 2007 and 2009 restructured some aspects of neurosurgical residency training. Since 2010, ongoing meetings of the One Neurosurgery Summit have provided strategic coordination for specialty definition, neurosurgical education, public policy, and governance. The Summit now includes leadership representatives from the Society of Neurological Surgeons, the American Association of Neurological Surgeons, the Congress of Neurological Surgeons, the American Board of Neurological Surgery, the Review Committee for Neurological Surgery of the Accreditation Council for Graduate Medical Education, the American Academy of Neurological Surgery, and the AANS/CNS Joint Washington Committee. Together, these organizations have increased the effectiveness and efficiency of the specialty of neurosurgery in advancing educational best practices, aligning policymaking, and coordinating strategic planning in order to meet the highest standards of professionalism and promote public health.

Background Deciding how to manage an unruptured intracranial aneurysm can be difficult for patients and physicians due to controversies about management. The decision as to when and how to intervene may be variable depending on physicians' interpretation of available data regarding natural history and morbidity and mortality of interventions. Another significant factor in the decision process is the patients' conception of the risks of rupture and interventions and the psychological burden of harboring an unruptured intracranial aneurysm. Objective  To describe which factors are being considered when patients and their physicians decide how to manage unruptured intracranial aneurysms.  Materials & methods  In a retrospective chart review study, we identified patients seen for evaluation of an unruptured intracranial aneurysm. Data was collected regarding patient and aneurysm characteristics. The physician note pertaining to the management decision was reviewed for documented reasons for intervention. Results  Of 88 patients included, 36 (41%) decided to undergo open or endovascular surgery for at least one unruptured intracranial aneurysm. Multiple aneurysms were present in 14 (16%) patients. Younger patients and current smokers were more likely to undergo surgery, but gender and race did not affect management. Aneurysm size and location strongly influenced management. The most common documented reasons underlying the decision of whether to intervene were the risk of rupture, aneurysm size, and risks of the procedure. For 23 aneurysms (21%), there were no factors documented for the management decision.  Conclusion  The risk of rupture of unruptured intracranial aneurysms may be underestimated by currently available natural history data. Major factors weighed by physicians in management decisions include aneurysm size and location, the patient's age, and medical comorbidities along with the risk of procedural complications. Additional data is needed to define specific aneurysm characteristics and patient factors that influence rupture, in particular in small aneurysms. Physicians should carefully document their rationale along with the patient's perspective given the controversial nature of these management decisions.

Purpose: Esthesioneuroblastoma is an uncommon malignancy of the head and neck for which there is no defined treatment protocol. The purpose of this study is to report our experience with the treatment and patterns of failure of this disease., Methods and Materials: From 1994 to 2012, 37 previously unreported patients with esthesioneuroblastoma were evaluated, and 32 eventually treated for cure at 2 academic medical centers. All patients were staged with Kadish criteria. The mean and median follow-ups were 96.1 and 76.5 months respectively (range 6-240 months)., Results: The Kadish stage was A in 6 patients, B in 13 patients, and C in 13 patients. Four patients were initially treated with concurrent chemo-radiation therapy. Twenty-eight patients were treated with primary surgery. Two (2) underwent open medial maxillectomy and 26 underwent craniofacial resection (open - 17, endoscopic - 9). Three patients received curative surgical resection only. Seven patients failed either within the cranial axis or distantly, 6 of the 7 are dead of disease, 10-194 months following initial treatment. Six patients had isolated neck recurrences, 4/6 were salvaged with neck dissection and additional chemo-radiation and remain alive 30-194 months following initial treatment. Estimated overall survival rate at 10 years was 78% based on Kadish and T stages., Conclusion: In this retrospective analysis of 32 patients, Kadish stage C and stage T3/T4 tumors were associated with worse outcome. Total radiation dose of 60 Gy, margin status, patient age, were not found to have significant prognostic value., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Neurotraumatology has its roots in ancient history, but its modern foundations are the physical examination, imaging to localize the pathology, and thoughtful medical and surgical decision making. The neurobiology of cranial and spinal injury is similar, with the main goal of therapies being to limit secondary injury. Brain injury treatment focuses on minimizing parenchymal swelling within the confined cranial vault. Spine injury treatment has the additional consideration of spinal coumn stability. Current guidelines for non-operative and operative management are reviewed in this chapter., (© 2014 Elsevier B.V. All rights reserved.)

Background: Restrictions on duty hours and shift length by the Accreditation Council for Graduate Medical Education and public pressure to reduce complications and to improve outcomes in the clinical educational environment have enhanced interest in the use of procedural and surgical simulation to train neurosurgical residents., Objective: To introduce simple, available, and, when possible, inexpensive model-based simulation for early learners into the initial stages of neurosurgical residency training., Methods: Simulation for early-stage trainees in neurological surgery has taken advantage of model-based systems. The Society of Neurological Surgeons postgraduate year 1 courses have served as one paradigm for designing and using model-based simulators for procedural and surgical skill training as part of a purpose-designed overall curriculum. Ongoing surveys of resident and faculty course participants have supported iterative improvements in simulator models and curriculum from year to year., Results: Simulation for basic neurosurgical and intensive care procedures has been undertaken through the use of available materials, surgical technology, and modifications of related existing model simulators. Simulation of common, standard surgical procedures for early learners may be broken into individual surgical skills and maneuvers to prepare trainees for safe practice of these component skills during live procedures under direct supervision appropriate to their training stage., Conclusion: Model-based simulation is particularly effective for early surgical learners as part of a coordinated curriculum. Almost 600 residents have used model-based simulation during the first 3 years of the Society of Neurological Surgeons boot camp courses, with ongoing modification and improvement of individual simulation models.

Object: In July 2010, the Society of Neurological Surgeons (SNS) introduced regional courses to promote patient safety and teach fundamental skills and knowledge to all postgraduate Year 1 (PGY1) trainees entering Accreditation Council for Graduate Medical Education (ACGME)-accredited US neurosurgery residency programs. Data from these courses demonstrated significant didactic learning and high faculty and resident satisfaction with hands-on training. Here, the authors evaluated the durability of learning from and the relevance of participation in SNS PGY1 courses as measured midway through PGY1 training., Methods: Resident participants were resurveyed 6 months after boot camp course attendance to assess knowledge retention and course effectiveness. Exposure to relevant hands-on experiences during PGY1 training and the subjective value of pre-residency simulated training in the courses were assessed., Results: Ninety-four percent of all residents entering US PGY1 neurosurgical training participated in the 2010 SNS boot camp courses. One hundred sixty-four (88%) of these resident participants responded to the survey. Six months after course completion, 99% of respondents believed the boot camp courses benefited beginning neurosurgery residents and imparted skills and knowledge that would improve patient care. The PGY1 residents' knowledge of information taught in the courses was retained 6 months after initial testing (p < 0.0001)., Conclusions: The learning and other benefits of participation in a national curriculum for residents entering PGY1 neurosurgical training were maintained 6 months after the courses, halfway through the initial training year.

The most prominent stigma of supratentorial skull base surgery is the defect caused by wasting of the temporalis muscle by denervation, devascularization, or rotation of the muscle. Any of the above may lead to a unilateral temporal deformity informally referred to patients as "the divot in my head." Abdominal free fat grafting has been used by surgeons for years to close posterior fossa defects with excellent results. We present our experience using abdominal free fat grafts to improve cosmetic results and to prevent cerebrospinal fluid leaks in supratentorial skull base surgery. The basic technique and its benefits are described.

Background: In July 2009, the Accreditation Council for Graduate Medical Education (ACGME) incorporated postgraduate year 1 (PGY1 intern) level training into all U.S. neurosurgery residency programs., Objective: To provide a fundamentals curriculum for all incoming neurosurgery PGY1 residents in ACGME-accredited programs, including skills, knowledge, and attitudes that promote quality, patient safety, and professionalism., Methods: The Society of Neurological Surgeons organized 6 regional "boot camp" courses for incoming neurosurgery PGY1 residents in July 2010 that consisted of 9 lectures on clinical and nonclinical competencies plus 10 procedural and 6 surgical skills stations. Resident and faculty participants were surveyed to assess knowledge and course effectiveness., Results: A total of 186 of 197 U.S. neurosurgical PGY1 residents (94%) and 75 neurosurgical faculty from 36 of 99 programs (36%) participated in the inaugural boot camp courses. All residents and 83% of faculty participants completed course surveys. All resident and faculty respondents thought that the boot camp courses fulfilled their purpose and objectives and imparted skills and knowledge that would improve patient care. PGY1 residents' knowledge of information taught in the courses improved significantly in postcourse testing (P < .0001). Residents and faculty particularly valued simulated and other hands-on skills training., Conclusion: Regional organization facilitated an unprecedented degree of participation in a national fundamental skills program for entering neurosurgery residents. One hundred percent of resident and faculty respondents positively reviewed the courses. The boot camp courses may provide a model for enhanced learning, professionalism, and safety at the inception of training in other procedural specialties.

Background: Incorporation of the first postgraduate year of training into neurological surgery residencies in 2009 posed new challenges to neurosurgical educators. A "boot camp" course was held in August 2009 to introduce first year neurosurgical trainees to various fundamental cognitive and practical skills., Objective: The effectiveness of this course was evaluated by electronic survey of all trainees and faculty members., Methods: Eighteen trainees entering 5 western neurosurgical residencies (in either the first or second postgraduate year) participated in a course taught by 10 faculty members at a single host institution (Oregon Health & Science University) for 2 days. All trainees completed an online survey evaluating the relevance and quality of each didactic and hands-on course component and answered additional questions about the goals and design of the course. Faculty members were also surveyed., Results: All trainees thought the course met its goals, provided relevant and useful information and experience, and was likely to improve patient care. In particular, hands-on procedural and operative course components were highly valued., Conclusion: A fundamental skills boot camp course for first year neurosurgical trainees seems valuable.

Object: Venous thromboembolism (VTE), a combination of deep venous thrombosis (DVT) and pulmonary embolism (PE), is a major cause of morbidity and death in neurosurgical patients. This study evaluates 1) the risk of developing lower-extremity DVT following a neurosurgical procedure; 2) the timing of initiation of pharmacological DVT prophylaxis upon the occurrence of VTE; and 3) the relationship between DVT and PE as related to VTE prophylaxis in neurosurgical patients., Methods: The records of all neurosurgical patients between January 2006 and December 2008 (2638 total) were reviewed for clinical documentation of VTE. As part of a quality improvement initiative, a subgroup of 1638 patients was studied during the implementation of pharmacological prophylaxis. A high-risk group of 555 neurosurgical patients in the intensive care unit underwent surveillance venous lower-extremity duplex ultrasonography studies twice weekly. All patients throughout the review received mechanical DVT prophylaxis. Pharmacological DVT prophylaxis, consisting of 5000 U of subcutaneous heparin twice daily (initially started within 48 hours of a neurosurgical procedure and subsequently within 24 hours of a procedure) was implemented in combination with mechanical prophylaxis. The DVT and PE rates were calculated for each group., Results: In the surveillance group (555 patients), 84% of the DVTs occurred within 1 week and 92% within 2 weeks of a neurosurgical procedure. There was a linear correlation between the duration of surgery and DVT development. The use of subcutaneous heparin reduced the rate of DVT from 16% to 9% when medication was given at either 24 or 48 hours postoperatively, without any increase in hemorrhagic complications. In the overall group (2638 patients), there were 94 patients who exhibited clinical signs of a possible PE and therefore underwent spiral CT; 22 of these patients (0.8%) had radiological confirmation of PE. There was no correlation between the use of pharmacological prophylaxis at either time point and the occurrence of PE, despite a 43% reduction in the lower-extremity DVT rate with pharmacological intervention., Conclusions: The majority of DVTs occurred within the first week after a neurosurgical procedure. There was a linear correlation between the duration of surgery and DVT occurrence. Use of early subcutaneous heparin (at either 24 or 48 hours) was associated with a 43% reduction of developing a lower-extremity DVT, without an increase in surgical site hemorrhage. There was no association of pharmacological prophylaxis with overall PE occurrence.

Object: This study was conducted to evaluate the value of postoperative CT scans in determining the probability of return to the operating room (OR) and the optimal time to obtain such scans to determine the effects of surgery., Methods: Between January and December 2006 (12 months), all postoperative head CT scans obtained for 3 individual surgeons were reviewed. Scans were divided into 3 groups, which were determined by the preference of each surgeon: Group A (early scans-scheduled between 0 and 7 hours); Group B (delayed scans-scheduled between 8 and 24 hours); and Group C (urgent scans-ordered because of a new neurological deficit). The initial scans were reviewed and analyzed in 2 different fashions. The first was to analyze the efficacy of the scans in predicting return to the OR. The second was to determine the optimal time for obtaining a scan. The second analysis was a review of serial postoperative scans for expected versus unexpected findings and changes in the acuity of these findings over time., Results: In 251 (74%) of 338 cases, the patients had postoperative head CT scans within 24 hours of surgery. Analysis 1 determined the percent of patients returning to the OR for emergency treatment based on postoperative scans: Group A (early)-133 patients, with 0% returning to the OR; Group B (delayed)-108 patients, with 0% returning to the OR; and Group C (urgent)-10 patients, with 30% returning to the OR (p < 0.05). Analysis 2 determined the optimal timing of postoperative scans and changes in scan acuity: Group A (early scan) had an 11% incidence of change in acuity on subsequent scans. Group B (delayed scan) had a 3% incidence of change in acuity on follow-up scans (p < 0.05)., Conclusions: Routine postoperative scans at 0-7 hours or at 8-24 hours are not predictive of return to the OR, whereas patients with a new neurological deficit in the postoperative period have a 30% chance of emergency reoperation based on CT scans. In addition, early postoperative scans (0-7 hours) fail to predict CT changes, which might evolve over time and may influence postoperative medical management.

Object: Mortality rate is a common outcome measure used by patients, families, physicians, insurers, and health care policy makers to evaluate and measure the quality of health care. The mortality index is a heavily used metric to measure survival, and is a key indicator in hospital report cards and national rankings. The significance of this metric is belied by the literature, which fails to accurately detail the overall mortality rate within the neurosurgical population. Given that there is no gold standard that can be used as a baseline, it is difficult to make durable interinstitutional comparisons concerning performance. In Part I of this paper, the authors examined an academic neurosurgical program's mortality rate and the effect of certain variables on this rate. In Part II, they assumed a broader perspective, examining a group of institutions, the University HealthSystem Consortium (UHC) Clinical Database/Resource Manager, and identifying factors that may be responsible for variability in the mortality index between hospitals., Methods: Over a 36-month period, the authors' neurosurgical service performed 3650 procedures. Monthly "mortality and morbidity" conference logs were reviewed to collect information on the number of deaths. Deaths were classified according to elective or nonelective admission status. Additionally, the authors reviewed the UHC Clinical Database/Resource Manager for information regarding mortality rates in various other neurosurgical programs. These data reflected a 12-month period. Comparisons of hospital mortality indices were based on the percentage of transferred patients (both emergency department [ED] and inpatient), whether a hospital was a designated Level 1 trauma center, whether a hospital was designated a certified stroke center, and also based on the number of Medicaid patients treated., Results: Sixty-two patients met the criteria to be considered neurosurgery-related deaths at the authors' institution (1.7% of all cases): 9 elective admissions (15%), 3 nonelective direct admissions (5%), 24 transfer patients (39%), and 26 ED admissions (42%). Causes of death included trauma (40%), stroke (33%), tumor (14%), spinal disease (8%), and infection (6%). Evaluation of the UHC data revealed that a mortality index of >or= 1.00 was seen in the following hospital types: trauma centers, hospitals with 11-20% Medicaid patients, and those with > 50,000 ED admissions. A nonstatistically significant trend toward increasing mortality rates was seen in hospitals with a lower percentage of elective neurosurgical cases, in Level 1 trauma centers, and in hospitals that were not certified stroke centers. Significance was seen in comparisons of hospitals with the highest and lowest mortality index quartiles in the following groups: trauma centers, hospitals with > 10% Medicaid patients, and hospitals with a high number of ED visits., Conclusions: Many variables appear to impact the mortality rate within the neurosurgical population. The authors' observations have illuminated some of the reasons why: the data are elusive, documentation is variable, and the modes of statistical analysis are questionable. The first step in addressing this issue is to identify that there is a problem. The authors believe that this study has done so. Presently there is no definitive or reliable source for rating the quality of overall neurosurgical care, nor is there a good and complete source for understanding the quality of neurosurgical care in the US. It is important to view these results as the initial steps to a better understanding of patient outcomes, their measures, and their impact on neurosurgical practice.

Injury to the anterior choroidal artery (AchA) can be devastating owing to the importance of the territory it supplies. The AchA is a known site of aneurysm formation, and is often exposed during various surgical and endovascular procedures. We report a patient with an aneurysm at the origin of the AchA, and an anomalous medial take off of the artery from the internal carotid artery, then a sharp lateral turn followed by a normal course toward the choroidal fissure, unreported to date to our knowledge. The aneurysm was treated successfully by endovascular therapy. The typical anatomy of the AchA, and reported variations in its origin are discussed. Thorough knowledge of the normal cerebrovascular anatomy and attention to variations play an important role in the successful management of patients with neurological vascular conditions.

Object: Vestibular schwannomas (VSs) are rare in the pediatric population. Most often, these lesions manifest as a bilateral disease process in the setting of neurofibromatosis Type 2. Even in the absence of additional clinical diagnostic criteria, the presentation of a unilateral VS in a young patient may be a harbinger of future penetrance for this hereditary tumor syndrome., Methods: The authors retrospectively reviewed the charts of a cohort of 7 patients who presented with apparently sporadic, unilateral VSs. These patients had previously undergone surgery via translabyrinthine, retrosigmoid, or combined approaches. Clinical outcomes were reviewed with emphasis on facial nerve function and follow-up for signs and symptoms of a heritable disorder., Results: All patients underwent microsurgical resection in a multidisciplinary effort by the senior authors. The average tumor size was 4.57 cm, with an average duration of symptoms prior to definitive diagnosis of 31.2 months. The tumor size at the time of presentation followed a trend different from reports in adults, while the duration of symptoms did not. At a follow-up average of 6.3 years (range 1-12 years), 100% of patients demonstrated good facial function (House-Brackmann Grade I or II). No patient in this cohort demonstrated symptoms, objective signs, or genetic analysis indicating the presence of neurofibromatosis Type 2., Conclusions: Diagnosis and management of sporadic, unilateral VSs in children is complicated by clinical presentations and surgical challenges unique from their adult counterparts. Careful consideration should be given to a heritable genetic basis for sporadic unilateral VS in the pediatric population. Results of genetic testing do not preclude the necessity for long-term follow-up and systemic investigation. In patients who present with large tumors, preliminary experience leads the authors to suggest that a combined retrosigmoid-translabyrinthine approach offers the greatest opportunity for preservation of facial nerve function.

Treatment of intracranial aneurysms involves many factors: patient preference and demographics; aneurysm size, site, geometry, access, and intrinsics; practitioner experience and availability; facility; technology; and ancillaries. Volume counts, teamwork enhancement, and management should be individualized.

Decompressive hemicraniectomy with durotomy is a life-saving procedure for patients who have large middle cerebral artery or carotid terminus strokes at high risk for malignant cerebral edema. Although randomized clinical trial data are not yet available, there are several case series that attempt to address issues of patient selection and timing of the procedure in the context of survival and functional outcomes. Patients who have an increased number of medical comorbidities, especially older age, are less likely to benefit from the procedure, but patients who have even large dominant hemispheric infarctions may do relatively well in certain circumstances.

We report the use of 16S ribosomal RNA gene amplification and sequencing to diagnose culture-negative intracerebral abscesses in younger patients. These 3 cases demonstrate the optimal application of gene sequencing from direct specimens for patients with negative culture results compromised by antibacterial therapy but histories highly suggestive of acute bacterial infection.

Objective: The absence of surgical subspecialty emergency care in the United States is a growing public health concern. Neurosurgery is a field lacking coverage in many areas of the country; however, this is generally thought to be of greater concern in rural areas. Because of decreasing numbers of neurosurgeons, medical malpractice, and liability concerns, neurosurgery coverage is becoming a public health crisis in urban areas. Our objective was to quantify neurosurgical emergency transfers to academic medical centers in Cook County, IL, including patient demographics, reasons for transfer, time lapse in transfer, and effects on patient condition., Methods: Data on neurosurgery emergency transfers was gathered prospectively by all five of the academic neurosurgery departments in Cook County, IL, over a 2-month period. Patient demographics devoid of identifiers, diagnosis, transfer origin, time lapse of transfer, and patient condition at the time of transfer and at the receiving hospital were recorded., Results: Two-hundred thirty emergent neurosurgical transfers occurred during the study period. The most common diagnoses were parenchymal intracerebral hemorrhage (33%) and subarachnoid hemorrhage (28%). Sixty-six percent of neurosurgical transfers to academic medical facilities originated at hospitals without full-time neurosurgery coverage. The mean time to transfer for all patients was 5 hours 10 minutes (standard deviation, 3 h 42 min; range, 1-20 h 12 min). A decline in Glasgow Coma Scale score was seen in 29 patients. A shortage of neurosurgical intensive care unit beds occurred on 55% of the days in the study. Only 19% of the emergency cases were related to cranial trauma, and only 3% of transfers came from Level 1 trauma centers., Conclusion: A combination of factors has led to decreases in availability of neurosurgical coverage in Cook County community hospital emergency departments. This has placed an increased burden on neurosurgical departments at academic centers, and, in some cases, delays led to a decline in patient condition. Eighty-one percent of the cases were not related to cranial trauma; thus, acute care trauma surgeons would be of little use. Coordinated efforts among local governments, medical centers, and emergency medical services to regionalize subspecialty services will be necessary to manage this problem.

The conventional wisdom resulting from the international, multicenter, trial of extracranial-intracranial bypass surgery is that this procedure offers no benefit. Because of the complex and unique circumstances of some, clinical experience and judgment must sometimes overrule some statistical conclusions.

Unlabelled: Intratemporal skull base tumors may invade the facial nerve in the horizontal (tympanic) or descending (vertical) segments, while parotid malignancies typically infiltrate the facial nerve at the stylomastoid foramen. This article will describe our results following intratemporal facial nerve grafting in 44 patients., Methods: This was a retrospective analysis of 44 patients requiring intratemporal facial nerve repair following lateral skull base tumor resection at our tertiary care, academic medical center., Results: Tumor histology included 17 parotid cancers, 13 temporal bone malignancies, 9 glomus tumors, 3 facial neuromas, and 2 endolymphatic sac tumors. The greater auricular nerve was used in 25 patients and the sural nerve was used in 19 cases. Forty patients were available for facial function assessment at 2 years. Using the House-Brackmann (H-B) recovery scale, the breakdown of patients by facial function was as follows: Grade I, 0 patients; Grade II, 4 patients; Grade III, 29 patients; Grade IV, 4 patients; Grade V, 3 patients; and Grade VI, 0 patients., Conclusions: Facial paralysis may occur from intrinsic or external lateral skull base invasion of the facial nerve. Intratemporal interposition grafting resulted in favorable facial function (H-B II or III) in 33 of the 40 (82.5%) patients at the 2-year assessment.

Objective: Accurate placement of ventricular catheters decreases the incidence of proximal catheter failure. The use of a frameless, interactive neuronavigational system can optimize catheter placement., Methods: Thirty-four ventricular catheters were placed using a Medtronic electromagnetic frameless neuronavigational system (Medtronic Navigation, Inc., Louisville, CO) during a 12-month period. The patients ranged in age from 11 months to 79 years; the mean age was 40.8 years. Nineteen male and 12 female patients participated in the study. The indications for ventricular catheter placement included obstructive hydrocephalus, normal pressure hydrocephalus, pseudotumor cerebri, intrathecal therapy, and tumor cyst aspiration., Results: No proximal failures have been reported to date. One infection necessitated shunt removal. Three postoperative deaths occurred because of non-catheter-related events., Conclusion: Frameless neuronavigation in the placement of ventricular catheters assures accurate catheter placement, thereby decreasing the incidence of proximal catheter failure. The absence of rigid head fixation allows additional cohorts to benefit from the apparatus. The use of the electromagnetic system provides a safe, simple, and easy adjunct to optimal catheter placement.

Objective: To review the intraoperative findings and facial nerve management in nine patients who presented with facial paralysis associated with glomus jugulare tumors., Study Design: A retrospective analysis of patient medical records., Setting: Tertiary care academic medical center., Patients: All patients who presented with facial paralysis and a glomus jugulare tumor who underwent surgical resection of their tumors at our institution., Intervention: A postauricular infratemporal fossa approach for tumor removal and greater auricular interposition neural repair., Main Outcome Measure: Intraoperative facial nerve findings and long-term facial recovery., Results: One hundred two patients underwent a postauricular infratemporal approach for resection of glomus jugulare tumor from July 1988 through July 2005. Nine of these patients presented with ipsilateral facial paralysis. The medial surface of the vertical segment was invaded by tumor in all nine cases. Facial recovery at 2 years was House-Brackmann Grade III in eight patients and Grade IV in one individual. Facial recovery did not significantly change after 2 years (mean follow-up of 7.4 years)., Discussion: Facial nerve invasion of the vertical segment occurred in 9 (9%) of 101 patients in our series. Facial nerve resection with interposition grafting resulted in House-Brackmann Grade III in eight (89%) of nine patients. Facial nerve dissection and preservation was not possible when preoperative facial paralysis was evident.

Objective: To present our experience in the diagnosis and management of 39 patients with lower cranial nerve schwannomas of the posterior fossa., Study Design: A retrospective chart review of patient medical records., Setting: Tertiary care, academic medical center., Patients: All patients with intracranial lower cranial nerve schwannomas treated surgically in our institution between July 1998 and July 2005., Intervention: A retrosigmoid, transcondylar, or combined approach was used for tumor recurrence., Results: Thirty-nine patients underwent surgical resection, with complete tumor removal in 32, near-total resection in 5 patients, and subtotal tumor excision in 2 patients. Long-term (mean, 8.2 years) magnetic resonance imaging surveillance demonstrated recurrent tumor in 2 of 32 complete resections and slow regrowth in 2 of 7 patients with known residual disease. Only one of these four patients required reoperation., Discussion: Intracranial schwannomas of the lower cranial nerves are relatively uncommon and may present with subtle or no clinical symptoms. Successful surgical resection with low risk of tumor recurrence can be achieved with the retrosigmoid or transcondylar approach. Morbidity, in this series, was primarily related to lower cranial nerve deficits.

Decompressive surgery with hemicraniectomy and durotomy for malignant MCA infarction remains a salvage procedure but can be associated with reasonable clinical outcomes in highly selected patients. This selection of patients appropriate for intervention is of the utmost importance, but exact criteria remain to be defined; older age and increased numbers of associated medical comorbidities seem to define a group of patients who would not derive long term benefit, however. The determination as to whether or not surgery is equally beneficial for dominant or nondominant hemispheric infarction is hampered by lack of good comparative data, but selected case series suggest that some patients who have dominant hemispheric infarction achieve a reasonable degree of independence. Although a well-defined principle of stroke practice is that "time is brain," there are no clear data as to when intervention should be done, as there are some patients who have large MCA infarction and who may not progress to cerebral herniation. Clinicians managing the growing population of patient status post hemicraniectomy should also be aware of this process of the syndrome of the trephined and the potential for resolution that may prompt earlier cranial reconstruction. At present, the decision to proceed with this aggressive intervention of hemicraniectomy and durotomy for large ischemic infarction remains a case-by-case individualized approach, based on patient and family preferences and clinicians' subjective perspective as to patients' potential for clinical recovery.

Treatment of intracranial aneurysms involves many factors: patient preference and demographics; aneurysm size, site, geometry, access, and intrinsics; practitioner experience and availability; facility; technology; and ancillaries. Volume counts, teamwork enhancement, and management should be individualized.

Objective: Patients who underwent skull base procedures have been noted to experience appreciable pain. This study examines pain after surgery and the effectiveness of patient controlled analgesia (PCA) with combination morphine ondansetron for analgesia and control of emesis., Study Design and Setting: A total of 120 skull base surgery patients were randomized to receive placebo, morphine, or morphine ondansetron. Demographic and intraoperative variables were recorded along with pain, nausea, vomiting, and rescue analgesics. Total PCA use, hospital stay, satisfaction, and cost were also compared., Results: Demographically the groups were similar. Pain was elevated with placebo PCA, and this group averaged twice as many analgesic rescues. Total usage time was lower with placebo PCA. Morphine ondansetron PCA had the lowest pain score with highest satisfaction. Nausea and vomiting was similar but female patients had more vomiting regardless of PCA group., Conclusions and Significance: The use of morphine PCA reduced pain and did not appreciably increase nausea or vomiting. The addition of ondansetron produced no real benefit and its PCA use cannot be justified., Ebm Rating: A-1b.

Objective: During the past decade, applications of anterior and anterolateral cranial approaches for both benign and malignant pathologies have expanded in frequency and application. Complications associated with these procedures impact significantly on patient outcome. The primary aim of this study is to detail the strategies for complication management and avoidance developed from experience with 120 patients who underwent anterior and anterolateral cranial base procedures during the past 14 years., Methods: Between July 1990 and February 2004, 62 male and 58 female patients underwent 120 combined (neurological surgery and otolaryngology joint participation) anterior and anterolateral cranial base procedures. Fifty-four percent had malignant pathology, and 46% had benign pathology. The approaches taken were transfacial (10%), extended subfrontal (33%), lateral craniofacial (23%), and anterior craniofacial (35%). Thirty-day morbidity and mortality were analyzed., Results: Twenty (17%) patients experienced at least one complication. Malignancy and reoperation, regardless of histology, appeared to affect the complication rate. A decline in complications occurred with experience, in part because of changes in management that reflected the complication experience (25% in Patients 0-31, 18% in Patients 32-70, 10% in Patients 71-120). Methodology is detailed for avoidance and management of retraction injury, infection, tension pneumocephalus, cerebrospinal fluid leak, pericranial flap failure, free flap sizing, dural banding, intracranial hypotension, and cerebrovascular events. Individual patient analysis, complications timing, and strategy for management are discussed., Conclusion: Improved patient outcomes for anterior and anterolateral cranial base surgery are, in part, directly related to the ability to avoid and manage associated complications. Experience, avoidance, and interdiction are key factors in complication management.

In this study we investigated the T-type calcium channel and its involvement in the cell division of U87MG cultured glioma cells and N1E-115 neuroblastoma cells. Using Western blot analysis, we found that expression of both alpha1G and alpha1H subunits of the T-type calcium channel decreased during conditions associated with a decrease in proliferation as evidenced by increased expression of cyclin D1, a marker for non-proliferating cells. Both serum starvation and application of mibefradil, a selective T-type calcium channel antagonist, resulted in a 50% decrease in the expression of alpha1G and alpha1H and a 700-900% increase in levels of cyclin D1 in U87MG and N1E-115 cells, respectively. Furthermore, overexpression of the alpha1H subunit resulted in a two-fold increase in cell proliferation compared to control cultures or cultures receiving an empty vector. In contrast, blocking expression of the alpha1G subunit using antisense oligonucleotides lead to a 70% decrease in proliferation of U87MG and N1E-115 cells compared to control cultures or cultures receiving a scrambled oligonucleotide. Our findings suggest that proliferation of U87MG glioma cells and N1E-115 is regulated by T-type calcium channel expression.

Background: Intracranial dural arteriovenous fistulas account for 10 to 15% of all intracranial arteriovenous malformations. Tentorial dural arteriovenous fistulas with spinal medullary venous drainage causing spinal cord myelopathy are very rare, but have been previously described. We describe a case using a cranio-orbito zygomatic approach with intraoperative angiography for the surgical treatment of a tentorial artery dural arteriovenous fistula causing spinal cord myelopathy., Case Presentation: A 42-year-old male presented complaining of a 1-year history of incoordination and dizziness and a 2-month history of progressive myelopathy with bowel and bladder incontinence. The patient had magnetic resonance imaging (MRI) performed along with cerebral and spinal angiography that revealed a right tentorial artery dural arteriovenous fistula with spinal medullary venous involvement down to T11. Angiographic embolization was attempted, but selective catheterization was unsuccessful. The patient underwent a cranio-orbito zygomatic approach with obliteration of the dural arteriovenous fistula. An intraoperative angiogram confirmed complete obliteration of the dural arteriovenous fistula., Conclusion: Intracranial dural arteriovenous fistulas are a rare cause of spinal cord myelopathy. When a patient presents with suspicion of spinal dural fistula and negative spinal angiography, an intracranial origin should be suspected and a cerebral angiogram performed. Skull base approaches along with intraoperative angiography provide an alternative modality for obliteration of the dural arteriovenous fistula nidus, thereby eliminating the venous congestion and hence the spinal cord ischemia.

Vertebral arteriovenous fistulas are rare in children and the congenital form has been seldom reported in the literature. Prior to using endovascular therapy techniques, only surgery was the main treatment. The most common endovascular treatment is through the use of detachable balloons. This report describes the clinical and radiological findings of a congenital vertebral artery fistula in a 20-month-old child. Balloons could not be safely employed; therefore, embolization was performed with Guglielmi detachable microcoils. We review the history and treatment of these lesions, their clinical presentation, and imaging features, including their outcome, with particular attention to the pediatric population.

Object: Malignant tumors of the skull base represent a group of diverse and infrequent lesions. Comprehensive oncological management requires a multidisciplinary team of neurological surgeons, otolaryngologists, radiation oncologists, plastic surgeons, and medical oncologists. The authors describe an institutional experience in performing 54 combined anterior-anterolateral cranial base resections for malignant disease., Methods: The technical considerations for preoperative workup, surgical approach, resection, and reconstruction are outlined and illustrated. Considerations for complication management and avoidance are detailed., Conclusions: Overall mortality (0%) and morbidity rates (18%) are acceptable. The influence on the natural history of the disease process is an ongoing study.

The etiology, classification, clinical presentation, complications, and intravascular routes to image and treat carotid-cavernous fistulas percutaneously are described. Endoarterial and transvenous approaches (through the jugular, inferior petrosal, or cavernous veins) are discussed in relation to the etiology, size, and characteristics of the fistulas, as well as in relation to the planned therapeutic approach and its possible complications. Possible outcomes, with particular attention to the internal carotid circulation, side effects, and complications also are discussed in relation to etiology and type of fistula. Four exemplary cases are presented.

Transverse-sigmoid sinus dural arteriovenous malformations (DAVM) are uncommon vascular lesions for which complete cure may be difficult to obtain. A wide variety of treatments for these lesions include observation, arterial compression, surgical resection, and endovascular embolization. We propose that transverse-sigmoid sinus DAVM can be completely cured by occluding the ipsilateral dural sinus with detachable balloon and Guglielmi detachable coils (GDC) coils before arterial feeder embolization with histoacryl. Three patients who presented with pulsatile tinnitus and normal magnetic resonance imaging (MRI) studies underwent angiography, which demonstrated transverse-sigmoid sinus DAVM. All three patients wer treated with retrograde transvenous sinus embolization with complete occlusion of the transverse-sigmoid sinus with detachable balloons and GDC coils with preservation of the vein of Labbé. Subsequently, the various feeders from the external carotid artery were embolized. The tentorial arteries arising from the ipsilateral internal carotid arteries were not embolized in any of the cases, which were still contributing to the DAVM. Complete cure with thrombosis of the tentorial branch of the internal carotid artery (ICA) was seen on follow-up angiogram 1 day after embolization in one patient and on 4-week and 6-week follow-up angiograms in the other two patients. Complete occlusion of the transverse sinus proximal to the vein of Labbé, in spite of incomplete arterial feeder embolization, can result in complete cure of the transversesinus dural AVF if adequate time is given for the remaining feeders to occlude, once the fistula is obliterated.

Mastery of the three-dimensional anatomic relationships of the cranial base/paranasal sinuses is required to reduce the incidence of iatrogenic surgical complications, facilitate complete tumor extirpation, and enhance functional outcomes. Real-time intraoperative localization technology is one method available to assist the cranial base surgeon. We report our institutional experience with the StealthStationtrade mark treatment guidance platform. Eighty-eight consecutive patients with pathology of the cranial base/paranasal sinuses were operated on with the aid of real-time frameless stereotactic localization. Preoperative image data sets were acquired with either CT or MRI scans. Patient demographics, accuracy of the data sets, surgical approaches, pathology, complications, and further applications of this technology are presented. Procedures were performed on 47 women and 41 men ranging in age from 6 to 85 years. In these 88 procedures, 44 MRI and 44 CT scans with a mean accuracy of 1.57 and 1.23 mm, respectively, were used. Approaches to the cranial base included midface degloving (25), endoscopic (23), craniofacial (13), maxillectomy (12), rhinotomy without maxillectomy (5), transoral (5), pterional (2), transcondylar (1), and transcervical (2). Indications for surgery included severe inflammatory disease of the paranasal sinuses with epidural or subdoral abscess, or both (7), cerebrospinal fluid fistula or encephalocele, or both (11), and 40 benign and 30 malignant tumors. Complications occurred in 10 of 88 patients (11%). Real-time intraoperative localization can be applied to cranial base surgery in a variety of scenarios. The instantaneous transfer of imaging data to the surgical field is useful in localizing pathology, enhancing operative safety, and reducing morbidity, thereby improving outcomes. This technology will certainly play an integral role in minimizing complications and improving surgical outcomes as cranial base surgery moves into the next millennium.

Background: The actual incidence of residual aneurysm after clipping is unknown. The natural history of residual aneurysm can be regrowth and hemorrhage. Intraoperative angiography offers a cost-effective, safe interdiction to the problem of residual aneurysm and parent vessel stenosis., Methods/results: Forty consecutive patients harboring 54 aneurysms underwent 42 operative procedures to clip 52 aneurysms, during which 220 intraoperative angiographic runs were performed. Ninety-three percent of the procedures were performed on patients with acute subarachnoid hemorrhage. There were 4 giant (>2.5 cm, 4/52 = 8%, all anterior circulation), 21 large (1.0-2.5 cm, 21/52 = 40%, 16/ 21 = 76% anterior circulation, 6/21 = 28% posterior circulation), and 27 small (<1.0 cm, 27/52-52%, 22/27 = 81% anterior circulation, 5/27 = 18% posterior circulation) aneurysms. Intraoperative angiography led to clip adjustment in 18/52 = 34% of aneurysms (4/18 = 22% for parent artery stenosis, 8/18 = 44% for residual aneurysm and 6/18 = 33% for both). Of the 18 adjustments made, 16 = 88% were made on giant or large aneurysms and two were small (one was a complex anterior communicating and one was a vertebral junction aneurysm). Follow-up angiography was performed on 26/42 = 62% of operative cases. Postoperative angiography confirmed intraoperative angiography in all cases. Two complications occurred during 220 angiographic runs: one embolic stroke and one incident of equipment failure., Conclusion: A grading scale was applied to test the relationship between anatomical site and size as they relate to the necessity for clip adjustment for complete aneurysm obliteration and/or parent artery compromise. Significance was related to site (basilar bifurcation, anterior communicating, middle cerebral bifurcation, and ophthalmic) and size (>1.0 cm), both as independent and codependent variables. An analysis of the cost-effectiveness of intraoperative angiography was demonstrated.

Abnormalities of the clivus/skull base occur most commonly as a result of disease spread from adjacent structures, but can also occur from primary involvement of the clivus. Traditionally, definitive diagnosis was made by CT guided biopsy or craniotomy. However, lesions can occur in this area that are not amenable to CT guided biopsy or craniotomy. Endoscopic transsphenoidal surgery can provide a safe method for obtaining a clival biopsy, debulking of tumor tissue, or definitive treatment without the morbidity and mortality of a craniotomy. This study was designed to describe our experience with the endoscopic approach to the skull base and clivus via the sphenoid sinus. A series of seven patients underwent endoscopic transsphenoidal biopsy of a sphenoid clival lesion. All patients avoided anticipated craniotomy, and definitive pathology was obtained in five of six patients. In two cases, excisional biopsy proved to be therapeutic. There were no deaths, and major complications included one CSF leak and one intraoperative hemorrhage, both of which were controlled immediately. The experience gained with these patients demonstrates the feasibility and safety of this new application of endoscopic sinus surgery for the diagnosis and possible treatment of lesions of the sphenoid and clivus.

The objective of this study is to determine the role of arachidonic acid (AA) in cell proliferation by inhibiting AA synthetic enzyme phospholipase A2 (PLA2) and to determine its involvement in the role of the second messenger intracellular calcium (Ca2+). Methods used to determine the effects on proliferation of cell cultures of primary meningioma and astrocytoma U373-MG included treatment with micromolar concentrations of PLA2 inhibitors 4-bromophenacylbromide and quinacrine. Effects of these drugs on proliferation were further investigated by the application of concentrations that inhibit growth by 50% while antagonizing these agents with AA replacement. Free cytosolic Ca2+ was measured with the use of fluorescent dye Fura-2 during PLA2 agonist/antagonist studies. These Ca2+ measurements were performed in the absence of extracellular Ca2+ to identify the contribution of intracellular Ca2+ sources. PLA2 inhibition resulted in decreased growth of cultured astrocytoma and meningioma cells in a dose-dependent manner in the micromolar range. This inhibitory effect was antagonized by the addition of AA. PLA2 inhibition caused an elevation of basal-cytosolic-free [Ca2+] while depleting internal Ca2+ stores. These Ca2+ changes were also antagonized by the addition of AA. In conclusion, these results demonstrate that AA, a PLA2 enzyme product, is involved in regulating the growth rate of these cell types. The PLA2 pathway also regulates the maintenance of the internal Ca2+ stores. Ca2+ is known to be a growth-related intracellular second messenger. These results suggest that the growth regulatory functions of AA are mediated by Ca2+-dependent mechanisms., (Copyright 1998 Academic Press.)

Cervical spondylosis is a disease that is often attributed to aging and considered the result of degenerative changes in the spine. The idea that there is a genetic predisposition to develop diseases of the skeletal elements of the spine has been discussed previously, but has never been proven conclusively. The authors report three cases of severe cervical spondylosis in patients who are first-degree relatives: a mother and her two sons. All three individuals had cervical disc herniations and stenosis at C3-4, C4-5, C5-6, and C6-7, and all three required decompressive procedures. The location and degree of cervical spondylosis were as similar among these three patients as they have been in identical twins reported in other studies. Such familial inheritance of cervical spondylosis has been reported only once. The existence of familial cervical spondylosis is not an unrealistic proposal because other studies have shown that genetics determines the shape of one's spine and that similar spines tend to degenerate in similar ways. Therefore, genetic counseling for a family such as the one reported here may prove to be of great benefit to warn siblings that they are at high risk for cervical spine injury. However rare it might be, familial cervical spondylosis may be a phenomenon that any spine surgeon should suspect in a family with cervical spine abnormalities found in several members.

Objective: Intimate to the application of lateral transtemporal approaches to the cranial base are the identification, manipulation, and/or the sacrifice of the venous anatomy of the inferolateral temporal lobe and the superior petrosal sinus and the transection of the tentorium. This study demonstrates the relationship and variability of the venous drainage of the lateral and inferior surfaces of the temporal lobe., Methods: Twenty-one specially prepared, injected cadaver specimens yielded 40 temporal lobes for examination. The venous systems in these specimens were traced from their origins on the temporal lobe (venous drainage complexes) to the transverse/petrosal sinuses, and the geometry of these venous complexes (venous configuration) was noted. The measurements of each complex's entry to the sinuses were noted., Results: Four distinct venous drainage complexes were identified: 1) the lateral complex, 2) the anteroinferior complex, 3) the medial-inferior complex, and 4) the posteroinferior complex. Three basic venous configurations were found: 1) the candelabra of veins uniting to form one large draining vein, 2) multiple independent draining veins, and 3) venous lakes running in the tentorium before entering the sinuses. The lateral complex, incorporating the classic "vein of Labbé," was present in 100% of the specimens. However, in the majority of cases, it did not represent the dominant venous drainage of the lateral and inferior surfaces of the temporal lobe., Conclusion: An understanding of the complexity and diversity of the venous drainage complexes and their configurations is necessary to avoid venous complications during lateral cranial base surgery.

Background: The development of frameless stereotaxis allows for repetitive intraoperative localization with millimeter accuracy. High-resolution computed tomographic (CT) angiography provides multiplanar, three-dimensional imaging of cerebral vascular lesions. The image data set generated during CT angiography can be used for localization in frameless stereotaxis when performed with appropriate fiducials in place., Methods: The feasibility of melding these two technologies was tested on a patient with a small (5 mm), distal ruptured posterior inferior cerebellar artery aneurysm, which was visualized by CT angiography and localized by frameless stereotaxis., Results: Visualization by CT angiography and intraoperative localization by frameless stereotaxis were successful., Conclusions: The practical application of this technology meld is demonstrated in this sample case. Applications to distal anterior cerebral artery aneurysms, abnormal flow-related aneurysms associated with arteriovenous malformations, and mycotic aneurysms are discussed.