Faculty Bibliography

Malignant brainstem gliomas (BSG) are rare tumors in adults, associated with a grim prognosis and limited treatment options. Currently, radiotherapy represents the mainstay of treatment, although new studies suggest an increased role for certain chemotherapeutic agents. Intravenous (IV) administration of bevacizumab (Avastin, Genentech Pharmaceuticals) has been shown to be active in the treatment of some enhancing malignant brainstem gliomas. The IV route of administration, however, carries a risk of systemic side effects such as bowel perforation, wound disrepair and pulmonary embolism. In addition, the percentage of IV drug that reaches the tumor site is restricted by the blood brain barrier (BBB).Weill Cornell Brain Tumor Center, Department of Neurosurgery, Weill Cornell Medical College of Cornell University: New York, NY, USA. This technical report describes our protocol in performing superselective intra-arterial cerebral infusion (SIACI) of bevacizumab using endovascular balloon-assistance in the top of the basilar artery in a patient with a recurrent malignant brainstem glioma. It represents the first time such a technique has been performed for this disease. This method of drug delivery may have important implications in the treatment of both adult and pediatric brainstem gliomas

BACKGROUND: Arteriovenous malformations (AVMs) are the most common cause of intracerebral hemorrhage in children. Different options exist for their successful management consisting of surgery, endovascular embolization, stereotactic radiosurgery, or a combination of these treatments. DISCUSSION: In this paper, we discuss the different treatment modalities in the treatment of pediatric cerebral AVMs emphasizing the role of surgery and endovascular embolization as a preoperative strategy

We present a case of delayed aggravation of initially-resolved symptoms in a patient after successful embolization of a T5 spinal dural arteriovenous (AV) fistula with N-butyl cyanoacrylate. The symptoms were attributed to venous thrombosis and resolved with systemic anticoagulation after five days of treatment. Although the most adequate treatment for preventing venous thrombosis after spinal dural AV fistula is not known, we describe this patient as a case for more aggressive prophylactic anticoagulation measures in the immediate post-embolization time period

BACKGROUND: Sphenoid wing meningiomas are slow-growing, well-circumscribed, and histologically benign lesions. The recurrence rate is low if removed completely at the time of surgery. Adequate surgical exposure with minimal morbidity is a challenge for those treating these lateral skull base lesions. OBJECTIVE: To describe our experience with the lateral tranzygomatic approach for resection of sphenoid wing meningioms in which the entire zygoma is mobilized and remains vascularized by masseter muscle attachments. METHODS: A retrospective review of the records of 19 patients who underwent sphenoid wing meningioma resection via a lateral transzygomatic approach between 1997 and 2007 was performed. A confirmatory cadaver dissection was performed to illustrate the anatomic nature of the technique. To achieve maximal exposure and minimal brain retraction, a lateral transzygomatic approach with osteotomies of the entire zygoma, which remains pedicled on the masseter muscle, was used. RESULTS: Nineteen patients with sphenoid wing meningioma underwent resection via a lateral transzygomatic approach. Complete resection of the meningioma was achieved in 17 cases. Morbidity consisted of temporary frontal nerve weakness (57.9%), mild to moderate temporalis atrophy (36.8%), and diplopia (15.8%). There were no cases of wound infection, bone malunion, or resorption. A mean follow-up period of 33.1 months (range, 2-71 months) revealed no recurrences after surgery as demonstrated by computed tomography or magnetic resonance imaging. CONCLUSION: The lateral transzygomatic approach to the sphenoid wing can be performed safely with minimal morbidity and facilitates complete resection of the tumor. Complete removal at an early stage is the best prognostic factor in treating sphenoid wing meningioma. This approach belongs in the armamentarium of surgeons who are involved in the resection of skull base neoplasms

BACKGROUND: A consecutive series of patients with intracranial aneurysms in the practice of one neurovascular surgeon was retrospectively reviewed to illustrate that one physician can become proficient in microneurosurgery as well as endovascular surgery and achieve favorable outcomes in both disciplines. This supports one model of training for cerebrovascular surgeons that includes the complimentary practice of open microneurovascular surgery with endovascular surgery. METHODS: The senior author (HAR) treated 351 patients with 413 aneurysms between July 2001 and March 2007. Of these, 172 patients (216 aneurysms) were treated with open microneurosurgical techniques and 179 patients (197 aneurysms) were treated using endovascular techniques. RESULTS: Complete obliteration was attained in 94.3% of clipped aneurysms, and 61.9% and 65.9% of coiled aneurysms immediately and after at least 6 months of follow-up, respectively. At latest evaluation, 93% of endovascular patients and 90% of microneurosurgical patients had good clinical outcomes (GOS, 4 or 5; mean follow-up, 23 months; combines ruptured and unruptured cohorts). Procedure-related mortality included 1 surgical patient and 2 endovascular patients. CONCLUSIONS: Because the fields of microvascular and endovascular surgeries are both technically complex, there has been concern that hybrid cerebrovascular surgeons cannot perform each technique with the skill necessary to achieve good outcomes. When compared to clipping and coiling reviews in the neurosurgical literature, we illustrate that one hybrid neurovascular surgeon is capable of attaining great facility in both techniques and that this type of physician will represent one practice model of cerebrovascular specialist in the future. This has potential implications for the training of hybrid cerebrovascular surgeons

Glioblastoma Multiforme (GBM) is a uniformly fatal disease with a median survival of approximately 15 months. Recent monoclonal antibody therapies such as Bevacizumab (Avastin) have been shown to be active in GBM and to prolong survival in patients with recurrent malignant glioma. Therefore, patients routinely receive intravenous (i.v.) Bevacizumab (10 mg/kg) every two weeks when they have recurred following standard therapy with chemoradiation. I.v Bevacizumab; however, can cause significant systemic side effects including bowel perforation and pulmonary embolism. In addition, the blood brain barrier (BBB) continues to provide an obstacle to the effective delivery of the antibody to the brain tumor bed. In order to overcome the BBB, and to limit the systemic toxicity of i.v. Bevacizumab, we have begun a Phase I clinical trial to test the safety of transient blood brain barrier disruption with intraarterial (IA) Mannitol followed by superselective intraarterial cerebral infusion (SIACI) of Bevacizumab. This case report describes the technical aspects of this procedure and its associated benefits and risks. This novel delivery method, which may herald the revival of Interventional Neuro-oncology, may significantly alter the way therapy is administered to patients with GBM

Summary: During embolization of a large frontal arteriovenous malformation (AVM), Onyx-18 (eV3) was injected into an M3 branch of the middle cerebral artery via a Marathon microcatheter (eV3). After 40 minutes of embolization, the microcatheter could not be retracted due to fixation within the Onyx cast despite prolonged, robust attempts. A balloon microcatheter (Hyperform(TM), eV3) was advanced distally and inflated to provide distal counter tension, allowing microcatheter retrieval with minimal traction on the vasculature

A 50-year-old woman underwent facial massage. After 13 days, she experienced left retro-orbital pain, ptosis, and miosis. Magnetic resonance imaging (MRI) showed stenotic dissection of bilateral cervical internal carotid and vertebral arteries. The intracranial vasculature was intact. She was treated conservatively with long-term oral anticoagulation and remains asymptomatic 18 months later

BACKGROUND AND PURPOSE: Hypotension and bradycardia are common in carotid artery stenting (CAS) and are particularly worrisome in the high risk patient who is typically referred for CAS. The purpose of this work was to assess the incidence and predictors of hypotension and bradycardia and the risk of their delayed occurrence after CAS. MATERIALS AND METHODS: A total of 53 men and 40 women (median age, 71 years) with symptomatic (57%) or asymptomatic (42%) carotid artery stenosis had CAS performed in our institution between December 2002 and January 2007. Patient vital sign records for the 12 hours post-CAS were analyzed. The relative decrease of blood pressure and pulse rate were used as primary end points, and the requirement of pressor or anticholinergic drugs was used as a surrogate end point. Significant predictors of hypotension and bradycardia were analyzed with a logistic regression model. Cumulative freedom from hypotension and bradycardia was calculated by using the Kaplan-Meier method. Negative predictive value (NPV) of screening for early hypotension and bradycardia was determined. RESULTS: The incidence of hypotension, bradycardia, and both was 14%, 23%, and 15%, respectively. Drug intervention was required in 45 patients (48%). Asymptomatic stenosis was an independent predictor of hypotension and bradycardia. Stenosis proximity to the bifurcation and dilation percentage were independent predictors of the drug intervention requirement. Seven patients (8%) had new onset of hypotension or bradycardia later than 6 hours post-CAS. The NPV of early hypotension and bradycardia was 97% and 93%, respectively. CONCLUSION: In this retrospective study, the risk of hypotension or bradycardia after CAS is significantly influenced by the degree of dilation performed, and the risk of their delayed occurrence may justify a minimum of 12 hours postprocedural vital sign monitoring

BACKGROUND: The false-negative rate of DSA in the setting of a ruptured cerebral aneurysm is approximately 15% (Topcuoglu M, Ogilvy C, Carter B, et al. Subarachnoid hemorrhage without evident cause on initial angiography studies: diagnostic yield of subsequent angiography and other neuroimaging tests. J Neurosurg 2003;98:1235-1240). Detecting these aneurysms is imperative to avoid repeat hemorrhage. Rarely, one is able to document the phenomenon of the disappearance and subsequent reappearance of the ruptured aneurysm. CASE DESCRIPTION: This is a case report of subarachnoid hemorrhage (SAH) in which a cerebral aneurysm of the M1 segment of the left proximal middle cerebral artery was initially detected by CTA at an outside hospital only to evade detection with both CTA and DSA at our institution. Repeat DSA 1 week later revealed the culprit aneurysm, which was then treated endovascularly. CONCLUSIONS: Patients with significant SAH and negative DSA findings should be considered for further diagnostic testing including CTA or repeat DSA. The current literature supports the strategy used at our institution of initial CTA and DSA in the setting of SAH, and then subsequent repeat DSA as warranted if the initial studies are nondiagnostic. Timing of repeat examination, as demonstrated in this case, should favor a shorter time course