Safety and Efficacy of Riluzole in Traumatic Spinal Cord Injury: A Systematic Review With Meta-Analyses.

Traumatic spinal cord injury (SCI) is a cause of significant morbidity, often resulting in long-term disability. We aimed to compare outcomes after riluzole versus patients who received placebo or standard of care with no specific intervention. MEDLINE, Embase, Scopus, and Cochrane Library database searches yielded 92 records, and five met the study inclusion criteria. Fixed-effect and random-effects models were used to establish odds ratios (ORs) and mean difference (MD) with 95% confidence intervals (CIs) for each outcome. The results of the pooled analysis showed that in patients with acute traumatic SCI, riluzole resulted in increased American Spinal Injury Association (ASIA) motor scores at 3 months (MD 0.26, 95% CI [-0.10,0.61], I2 = 0%; p = 0.157) and 6 months (MD 0.21, 95% CI [-0.17,0.60], I2 = 0%; p = 0.280) and change in ASIA Impairment Scale (AIS) at 3 months (OR 0.59, 95% CI [-0.12,1.30], I2 = 0%, p = 0.101) and 6 months (OR 0.28, 95% CI [-0.50,1.06], I2 = 0%, p = 0.479) in comparison to the control groups, though not to a level of statistical significance. Riluzole resulted in fewer adverse events than the control groups (OR -0.12, 95% CI [-1.59,1.35], I2 = 0%, p = 0.874) and lower mortality (OR -0.20, 95% CI [-1.03,0.63], I2 = 0%, p = 0.640), though also not to a level of statistical significance. These meta-analyses suggest that riluzole for the treatment of traumatic SCI is safe and results in improved neurological outcomes when compared to controls, though not to a level of statistical significance. More robust prospective, randomized studies are necessary to help inform the safety and efficacy of riluzole for traumatic SCI.

The complete anterior petrosectomy: an expanded extended-middle fossa approach with removal of the infratrigeminal petrous apex and drilling of the lateral clivus.

Intradural exposure in the extended middle fossa anterior transpetrosal approach is traditionally limited to the inferior petrosal sinus inferomedially. Expanding bone removal of the petrous apex around the petrous internal carotid artery (ICA), underneath the trigeminal ganglion/mandibular nerve, and into the lateral component of the clivus can significantly expand the limits of this approach beyond the inferior petrosal sinus and allows for exposure of the midline structures, aspects of the contralateral inferior clival region, and, when high riding, the vertebrobasilar junction. To date, no descriptive techniques for drilling into the lateral clivus in this approach have been published. The authors provide a detailed stepwise description of their complete anterior petrosectomy, in use at their institution, that involves skeletonization of the posteromedial petrous ICA, gentle elevation of the trigeminal ganglion/mandibular nerve, removal of the infratrigeminal petrous apex, and two techniques for drilling into the lateral clivus along the petroclival fissure. These techniques provide a direct and unobstructed corridor to the midpetroclival region and ventral brainstem with greater maneuverability and enhanced control of the midline structures, which is especially useful for resection of petroclival meningiomas, chondrosarcomas, and giant vascular lesions of the mid- and upper basilar artery and its proximal branches.

Intravascular ultrasound to aid in the diagnosis and revision of an intra-aortic pedicle screw: illustrative case.

BACKGROUND: Pedicle screw impingement on vessel walls has the potential for complications due to pulsatile effects and wall erosion. Artifacts from spinal instrumentation create difficulty in accurately evaluating this interface. The authors present the first case of intravascular ultrasound (IVUS) used to characterize a pedicle screw breach into the aortic lumen. OBSERVATIONS: A 21-year-old female with surgically corrected scoliosis underwent computed tomography angiography (CTA) 3 years postoperatively, which revealed a pedicle screw within the thoracic aorta lumen. Metal artifact distorted the CTA images, which prompted the decision to use intraoperative IVUS. The IVUS confirmed the noninvasive imaging findings and guided final decisions regarding aortic endograft size and location during spine hardware revision. LESSONS: For asymptomatic patients presenting with pedicle screws malpositioned in or near the aorta, treatment decisions revolve around the extent of vessel wall penetration. Intraluminal depth can be obscured by artifact on computed tomography or magnetic resonance imaging or inadequately evaluated by a transesophageal echocardiogram. In our intraoperative experience, IVUS confirmed the depth of vessel lumen violation by a single pedicle screw and no wall penetration by two additional screws of concern. This was useful in deciding on thoracic endovascular aortic repair graft size and landing zone and facilitated safe spinal instrumentation removal and revision.

Frailty in middle cranial fossa approach for encephalocele or cerebrospinal fluid leak repair.

Objective: The modified 5-item frailty index (mFI-5) is a concise, comorbidity-based risk stratification tool that can predict adverse outcomes after surgery. The goal of this study was to understand the frailty of patients undergoing surgery for temporal encephalocele or cerebrospinal fluid (CSF) leak and the utility of mFI-5 for predicting increased post-operative outcomes. Methods: A retrospective review of adults with temporal encephalocele or CSF leak who underwent middle cranial fossa (MCF) approach craniotomies with or without mastoidectomy from January 2015 through August 2021 at a tertiary care academic medical center was performed. Patients who underwent additional surgeries or extended surgical approaches were excluded. The mFI-5 was calculated for all patients. Demographic and clinical data were obtained from the medical record. Results: Thirty-six patients underwent 40 MCF approach craniotomies for temporal encephalocele or CSF leak, including three revision cases and one patient with sequential bilateral operations. Mean age was 54.1 ± 10.8 years, and 66.7% were female. In the univariable regression analysis, mFI-5 score, age, and procedure time use were significantly associated with increased hospital length of stay (LOS) but not increased intensive care unit (ICU) LOS. Anesthesia time and lumbar drain were significantly associated with increased hospital LOS and ICU LOS, and they remained significantly associated with increased hospital LOS in the multivariable model. Conclusion: Frailty is associated with increased hospital LOS stay among patients undergoing MCF approach for CSF leak or encephalocele. Reducing anesthesia time and avoiding lumbar drain use are potentially modifiable risk factors that can reduce the LOS and associated costs. Level of Evidence: 4.

Expansion of the Foramen Ovale in Patients With Cerebrospinal Fluid Leak or Encephalocele.

OBJECTIVE: Spontaneous cerebrospinal fluid (CSF) leaks are associated with elevated intracranial pressure and idiopathic intracranial hypertension (IIH). Skull base erosion and widening of the foramen ovale have been reported in patients with IIH. This study sought to investigate changes in the size of the foramen ovale and foramen spinosum in patients with IIH, spontaneous CSF leak, and encephalocele. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary care academic medical center. PATIENTS: Adult patients treated from 2014 to 2018 with computed tomographic imaging of the head and who were diagnosed with IIH, encephalocele, or CSF leak. INTERVENTION: Two blinded observers measured the long and short axes of the foramen ovale and foramen spinosum on axial computed tomographic images. Measurements were used to calculate the approximate elliptical cross-sectional area of the foramina. MAIN OUTCOME MEASURES: Length, width, and area of the foramen ovale and foramen spinosum. RESULTS: A total of 264 patients were identified meeting the inclusion criteria and were placed into three groups. There were 170 patients with IIH, 48 with spontaneous CSF leak or encephalocele (CSF/E group), and 46 with traumatic or iatrogenic CSF leak (control group). Mean foramen ovale short axis (4.85 ± 1.00 mm) and cross-sectional area (30.17 ± 9.25 mm2) in the CSF/E group were significantly increased compared with measurements in patients with IIH or the control groups. Foramen ovale size was positively correlated with age in the CSF/E group. No significant difference in foramen spinosum size was found. CONCLUSION: Skull base defect resulting in spontaneous CSF leak or encephalocele is associated with enlargement of the foramen ovale on axial computed tomography.

Erroneous Central Venous Catheter Placement: Multidisciplinary Primary Surgical Repair of the Vertebral Artery.

Central venous catheters are a common practice in critical care medicine. These lines are of particular importance when a patient needs large volume resuscitation or medications that cannot be infused through a peripheral line. Even though central venous catheters are frequently utilized, they are associated with potentially significant risks that one must be aware of when attempting placement. The anatomy and pertinent complications are key for any healthcare professional to be aware of during this procedure. As such, vascular injury has been described in the literature, but vertebral artery injury and common repair techniques are less common. Primary repair of the second vertebral artery segment is infrequently detailed in the literature and this report describes pertinent case details and plan of action for identification and repair of iatrogenic vertebral artery injury following catheter placement.

Atrioesophageal Fistula: Considerations for the neurological clinician.

Atrioesophageal fistula (AEF) is a rare complication of cardiac ablation for atrial fibrillation. It can present in many ways, but neurological signs and symptoms are common initial signs sometimes resulting in neurosurgeons and neurologists first evaluating patients with the condition. We present a case report of at 68-year-old female who presented with acute stroke symptoms and multifocal hemorrhages on MRI who was worked up through our neurosurgery department and diagnosed with AEF. This case highlights three clues to alert neurological clinicians to AEF as a possible diagnosis; clinical worsening of neurological symptoms in correlation to episodes of emesis, septic emboli on CT/MRI, and bacteremia caused by a gram positive oral or GI flora. If neurological clinicians encounter these red flags, an immediate CT of the chest and abdomen and consultation with cardiothoracic surgery may be life-saving.

Hemorrhage Rate After External Ventricular Drain Placement in Subarachnoid Hemorrhage: Time to Heparin Administration.

OBJECTIVE: The use of antiplatelet or anticoagulants has previously been shown to increase hemorrhagic complications of ventricular catheterization. Although heparin use 24 h after ventriculostomy appears safe, the safety of heparin immediately (within 4 h) after ventriculostomy is unknown. The objective of this study was to assess the safety of heparin immediately (within 4 h) after ventriculostomy in subarachnoid hemorrhage (SAH) patients undergoing endovascular treatment. PATIENTS AND METHODS: This is a retrospective cohort study of 46 patients with aneurysmal SAH secondary to aneurysm rupture who required ventriculostomy. Post-ventriculostomy imaging was carefully reviewed for tract hemorrhaging. Timing of heparinization was noted. Early heparinization was within 4 h after ventriculostomy, and intermediate heparinization was between 4 and 24 h after ventriculostomy. RESULTS: Overall, the tract hemorrhage rate was 26.1% for the study cohort-mostly grade I tract hemorrhages-consistent with the existing literature. The tract hemorrhage rate in the early (<4 h) heparin group was a remarkable 58.8%. The hemorrhages were also notably larger in the early (<4 h) heparin group. CONCLUSION: Although heparin appears to be safe after 4 h, immediate heparinization (within 4 h) after ventriculostomy significantly increases the odds of tract hemorrhage. Additional time should be afforded between ventriculostomy and heparinization to avoid potentially devastating external ventricular drain tract hemorrhage. It is advisable to wait a sufficient time (at least 4 h) after ventriculostomy before embarking on endovascular treatment of ruptured aneurysms.

Impact of a Vascular Neurosurgery Simulation-Based Course on Cognitive Knowledge and Technical Skills in European Neurosurgical Trainees.

OBJECTIVE: To assess microsurgical and diagnostic cerebral angiography modules and their corresponding objective assessment scales as educational tools for European neurosurgical residents at the European Association of Neurosurgical Societies Resident Vascular Neurosurgery course, which was held in Prague, Czech Republic, on September 2013. Microsurgical skills and cerebral angiography are fundamental skills in vascular neurosurgery. There is a need to develop a simulation-based curriculum focusing on these skills for neurosurgical trainees worldwide. METHODS: The course consisted of 2 modules: microanastomosis and diagnostic cerebral angiography. In addition to an initial screening survey, each module was divided into 3 components: 1) a before didactic cognitive knowledge and technical skills testing, 2) a didactic lecture, and 3) an after didactic cognitive knowledge and technical skills testing. We compared the trainees' cognitive and technical scores from the before and after testing phases. Wilcoxon sum rank test was used to test statistical significance. RESULTS: The knowledge test median scores increased from 63% and 68% to 80% and 88% (P < 0.01) on the microanastomosis and cerebral angiography modules, respectively. The practical hands-on simulation assessment median scores increased from 42% and 50% to 50.5% and 68% (P < 0.01) on the microanastomosis and cerebral angiography modules, respectively. CONCLUSIONS: Our course suggests that a simulation-based vascular neurosurgery curriculum is feasible and may enhance resident knowledge and technical proficiency.

Atypical presentation of primary central nervous system non-Hodgkin lymphoma in immunocompetent young adults.

OBJECTIVE: Primary central nervous system non-Hodgkin lymphoma (PCNSL) is a malignant lymphoma limited to the cranial-spinal axis in the absence of systemic lymphoma. Historically, PCNSL accounts for fewer than 5% of all cases of primary intracranial neoplasms. PCNSL is rare in immunocompetent young adults. Although the prognosis for PCNSL is poor, approximately 20%-30% percent of cases achieve a cure. METHODS: We report two cases of PCNSL originating in the ventricle in otherwise healthy immunocompetent young adults. RESULTS: A 27-year-old man presented with 10 days of nausea, vomiting, and headache and was found to have a large intraventricular mass emanating from the choroid plexus with resultant hydrocephalus. He underwent placement of external ventricular drain and systemic and intrathecal chemotherapy for cytologically proven PCNSL. A 31-year-old pregnant woman presented with headaches, vision difficulties, and ataxia and was found to have a septum pellucidum mass. She underwent craniotomy and subtotal resection of the mass with subsequent systemic therapy and whole brain radiation for treatment of PCNSL. CONCLUSIONS: To our knowledge, this is the first report of primary CNS lymphoma of the choroid plexus and septum pellucidum in otherwise healthy, immunocompetent young adults.

Adenosine for temporary flow arrest during intracranial aneurysm surgery: a single-center retrospective review.

BACKGROUND: Clip application for temporary occlusion is not always practical or feasible. Adenosine is an alternative that provides brief periods of flow arrest that can be used to advantage in aneurysm surgery, but little has been published on its utility for this indication. OBJECTIVE: To report our 2-year consecutive experience with 40 aneurysms in 40 patients for whom we used adenosine to achieve temporary arterial occlusion during aneurysm surgery. METHODS: We retrospectively reviewed our clinical database between May 2007 and December 2009. All patients who underwent microsurgical clipping of intracranial aneurysms under adenosine-induced asystole were included. Aneurysm characteristics, reasons for adenosine use, postoperative angiographic and clinical outcome, cardiac complications, and long-term neurological follow-up with the modified Rankin Scale were noted. RESULTS: Adenosine was used for 40 aneurysms (10 ruptured, 30 unruptured). The most common indications for adenosine were aneurysm softening in 17 cases and paraclinoid location in 14 cases, followed by broad neck in 12 cases and intraoperative rupture in 6 cases. Troponins were elevated postoperatively in 2 patients. Echocardiography did not show acute changes in either. Clinically insignificant cardiac arrhythmias were noted in 5 patients. Thirty-six patients were available for follow-up. Mean follow-up was 12.8 months. The modified Rankin Scale score was 0 for 29 patients at the time of the last follow-up. Four patients had an modified Rankin Scale score of 1, and scores of 2 and 3 were found in 2 and 1 patients, respectively. CONCLUSION: Adenosine appears to allow safe flow arrest during intracranial aneurysm surgery. This can enhance the feasibility and safety of clipping in select circumstances.

Periprocedural MRI perfusion imaging to assess and monitor the hemodynamic impact of intracranial angioplasty and stenting for symptomatic atherosclerotic stenosis.

We aimed to assess the clinical value of MRI perfusion imaging in the periprocedural management of intracranial atherosclerosis, analyzing if changes in mean transit time (MTT), cerebral blood volume (CBV) and cerebral blood flow (CBF) correlated with angiographic outcomes. Pre-procedural and post-procedural MRI perfusion was performed on six patients who underwent angioplasty and/or stenting for symptomatic intracranial atherosclerosis. MTT, CBV and CBF were analyzed and graded. In 83% of patients, perfusion imaging correlated with angiographic outcomes. Perfusion parameters improved to normal in two patients. Two showed marked improvement and one showed mild improvement. In one patient, the results of the post-procedural MRI perfusion prompted an angiogram, which confirmed stent occlusion. Semi-quantitative scores of MTT and CBF changed over time (p=0.05, p=0.03) whereas CBV did not change significantly (p>0.05). We conclude that MRI perfusion appears a promising technique for analyzing the impact of intracranial stenosis on cerebral hemodynamics before and after treatment.

High-grade dural arteriovenous fistula simulating a bilateral thalamic neoplasm.

Dural arteriovenous fistulae (dAVF) provide a diagnostic challenge and must be part of a broad differential in pursuit of a difficult diagnosis or unusual presentation. This case report demonstrates an initially misguided diagnosis of bilateral thalamic neoplasm and demonstrates the importance of continued pursuit until the correct diagnosis is obtained. Moreover, to our knowledge, this is the first reported case of a dAVF simulating a bilateral thalamic neoplasm. We present a patient with a provisional diagnosis of bilateral thalamic neoplasm based on clinical history and an advanced imaging workup including MR spectroscopy. Subsequent biopsy suggested venous congestion, hypoxia, and edema without neoplasia. Routine post-operative CT the following day revealed suggestion of dAVF due to the presence of residual contrast from prior unrelated abdominal CT. Cerebral angiography eventually revealed a Cognard grade IIb dAVF. Trans-arterial Onyx embolization resulted in a dramatic clinical and radiographic improvement. This case highlights an unusual presentation and challenging diagnosis of a dAVF and the importance of pursuing the correct diagnosis.

Type I spinal dural arteriovenous fistulas: historical review and illustrative case.

Type I spinal dural arteriovenous fistulas are the most common vascular malformation of the spinal cord, and an important cause of reversible progressive myelopathy. This lesion remains underdiagnosed, with most patients presenting late in the course of the disease. In this article the authors provide a review of the literature with particular attention to historical aspects related to the pathophysiology, diagnosis, classification, clinical findings, natural history, and treatment of this lesion. An illustrative case is also provided.

Basilar artery occlusion following C1 lateral mass fracture managed by mechanical and pharmacological thrombolysis.

BACKGROUND: Vertebral artery injury following cervical spine trauma can be associated with stroke. We present a case of a C1 fracture resulting in vertebral artery dissection and neurological decline as a result of basilar artery occlusion treated with chemical and mechanical thrombolysis resulting in basilar artery patency and clinical improvement. CASE DESCRIPTION: The patient is a 43-year-old female who was involved in a motor vehicle collision where she sustained multiple cervical spine injuries including a comminuted fracture of the left lateral mass of C1 resulting in vertebral artery dissection which eventually led to a basilar artery embolus and occlusion. A total of 15 mg of intraarterial tissue plasminogen activator was infused throughout the clot, followed by mechanical clot embolectomy using an FDA-approved device. Her neurological exam improved post-procedurally and she was discharged with a left hemiparesis to a rehabilitation facility 3 weeks after admission. At 15 month follow up, she is neurologically intact with the exception of some subtle difficulty with fine motor movement in the right upper extremity and mild dysmetria on the right. CONCLUSIONS: With this case, we report a rare and potentially devastating complication of C1 fracture. To our knowledge there are only two previously reported cases where a C1 fracture has been associated with basilar artery occlusion resulting in death and locked-in syndrome respectively. In this case, chemical thrombolysis and mechanical thrombectomy resulted in recanalization of the basilar artery with excellent long-term neurological outcome.

Symptomatic spontaneous intracranial carotid artery dissection treated with a self-expanding intracranial nitinol stent: a case report.

BACKGROUND: Although extracranial carotid dissection with stroke is common, intracranial dissection with stroke is rare. Stenting has been used to treat extracranial carotid dissections. Intracranially, however, it is only recently that stents have become a feasible option for this disease. We present a case of a spontaneous intracranial CAD with progressive symptoms despite medical management treated with a self-expanding intracranial micronitinol stent. CASE DESCRIPTION: A 47-year-old, right-handed woman presented to the emergency department after noticing left-sided face and arm weakness and numbness, along with slurred speech. The patient was started on aspirin 325 mg/d orally and lovenox 40 mg/d subcutaneously. On hospital day 2, the patient was noted to have repeated episodes of weakness and numbness on the left side and MRI evidence of a new stroke. A diagnostic cerebral angiogram from a selective right internal carotid injection revealed a flow-limiting stenosis secondary to a dissection of the supraclinoid internal carotid artery with severe flow limitation to the hemisphere. Endovascular management was decided on, and a Neuroform stent measuring 4.5 x 20 mm (Boston Scientific Corporation, Natick, Mass) was deployed across the dissection with significant improvement of flow to that hemisphere on the poststent angiogram. CONCLUSIONS: This case illustrates the successful off-label use of a self-expanding intracranial nitinol stent to treat a symptomatic intracranial internal CAD in the setting of failure of traditional medical management. This is a promising application of novel endovascular technology.

Revascularization for complex intracranial aneurysms.

The modern management of intracranial aneurysms includes both constructive and deconstructive strategies to eliminate the aneurysm from the circulation. Both microsurgical and endovascular techniques are used to achieve this goal. Although most aneurysms can be eliminated from the circulation with simple clip reconstruction and/or coil insertion, some require revascularization techniques to enhance tolerance of temporary arterial occlusion during clipping of the aneurysm neck or to enable proximal occlusion or trapping. In fact, the importance of revascularization techniques has grown because of the need for complex reconstructions when endovascular therapies fail. Moreover, the safety and feasibility of bypass have progressed due to advances in neuroanesthesia, technological innovations, and ~ 5 decades of accumulating wisdom by bypass practitioners. Cerebral revascularization strategies become necessary in select patients who possess challenging vascular aneurysms due to size, shape, location, intramural thrombus, atherosclerotic plaques, aneurysm type (for example, dissecting aneurysms), vessels arising from the dome, or poor collateral vascularization when parent artery or branch occlusion is required. These techniques are used to prevent cerebral ischemia and subsequent clinical sequelae. Bypass techniques should be considered in cases in which balloon test occlusion demonstrates inadequate cerebral blood flow and in which there is a need for Hunterian ligation, trapping, or prolonged temporary occlusion. This review article will focus on decision making in bypass surgery for complex aneurysms. Specifically, the authors will review graft options, the utility of balloon test occlusion in decision making, and bypass strategies for various aneurysm types.

Spontaneous spinal epidural hematoma of unknown etiology: case report and literature review.

INTRODUCTION: Our objective is to emphasize the importance of recognizing and rapidly treating spontaneous spinal epidural hematoma (SSEH). SSEH is a pathologic entity traditionally thought to be exceptionally rare but which, in the era of MR imaging, is becoming increasingly prevalent, and which if treated with sufficient rapidity can be completely curable. CLINICAL PRESENTATION: Our particular case presented with clumsiness, neck pain with radiation to both arms, and bilateral arm weakness. According to the literature surveyed, most patients present with severe back and/or neck pain, often with a radicular component, followed by motor and/or sensory deficits. INTERVENTION/TECHNIQUE: C5-6 decompressive hemilaminectomy with evacuation of hematoma. CONCLUSION: As evidenced in the literature, outcome depends on time to operation and prognosis is impacted by age and preoperative deficit. Because of the high risk of poor outcome without treatment, SSEH should always be a diagnostic consideration in patients whose presentation is even slightly suggestive. Rapid, appropriate treatment of these patients can often lead to complete recovery of function, whereas any delay in appropriate treatment can be catastrophic.

Modern endovascular and aesthetic surgery techniques to treat arteriovenous malformations of the scalp: case illustration.

BACKGROUND: Arteriovenous malformations of the scalp consist of abnormally connecting arterial feeding vessels and draining veins, devoid of a normal capillary bed within the subcutaneous fatty layer of the scalp. We present a case of a left temporal scalp AVM treated for aesthetic and pain-related concerns. A multidisciplinary approach combining endovascular AVM embolization and AVM excision with local flap reconstruction was chosen. CASE DESCRIPTION: The patient presented with a progressive painful pulsatile mass in the left temporal region. On examination, there was no evidence of any facial nerve compromise or any other neurologic deficits. Computed tomographic angiography revealed a 6-mm lesion located totally within the scalp and not associated with bone or periosteum. A recommendation was made to proceed with preoperative embolization to facilitate surgical resection. The AVM was occluded endovascularly using multiple detachable platinum coils, and the patient was neurologically intact. The following day, the patient was taken to the operating room. By that time, the mass was minimally pulsatile. The AVM was resected en bloc, and a 3-layered intermediate closure of the 5.5-cm defect was then performed. The procedure was well tolerated, and the patient had an uneventful postoperative course. CONCLUSIONS: Scalp AVMs are interesting lesions with heterogeneous anatomical features. Treatment can be optimized in a multidisciplinary environment, using a prescribed treatment algorithm to minimize the size of soft/hard tissue defect and enhance cosmesis. Careful selection of therapeutic modalities based on AVM anatomy and aesthetic concerns can lead to safe and durable results with high patient satisfaction rates.

Pros, cons, and current indications of open craniotomy versus gamma knife in the treatment of arteriovenous malformations and the role of endovascular embolization.

The successful treatment of an intracranial arteriovenous malformation poses both technical and conceptual problems to the neurosurgeon. Treatment decisions are made in light of current understanding of the natural history of these lesions. It is important to understand the pros, cons and current indication of open craniotomy vs. gamma knife in the treatment of arteriovenous malformations and the role of endovascular embolization. Surgical removal of an arteriovenous malformation is indicated when the operative risk is less than the morbidity and mortality associated with its natural history. The treatment goal of complete angiographic obliteration of arteriovenous malformations is achieved most effectively by microneurosurgery in low-grade lesions. Large lesions frequently require a combination of embolization and microsurgery. Although recent advances in technology and medical management have allowed previously inoperable arteriovenous malformations to be surgically excised, there is still a small group of arteriovenous malformations that cannot be excised safely due to their size and location. Stereotactic radiosurgery is clearly an important adjunct in the multimodality treatment approach for large arteriovenous malformations. Endovascular embolization can potentially increase safety and efficacy in the treatment of arteriovenous malformations when applied to selective cases with well-defined treatment goals.