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Object: A small percentage of cerebral aneurysms rupture, but when they do, the effects are devastating. Current management of unruptured aneurysms consists of surgery, endovascular treatment, or watchful waiting. If the biology of how aneurysms grow and rupture were better known, a novel drug could be developed to prevent unruptured aneurysms from rupturing. Ruptured cerebral aneurysms are characterized by inflammation-mediated wall remodeling. The authors studied the role of stromal cell-derived factor-1 (SDF-1) in inflammation-mediated wall remodeling in cerebral aneurysms., Methods: Human aneurysms, murine carotid artery aneurysms, and murine intracranial aneurysms were studied using immunohistochemistry. Flow cytometry analysis was performed on blood from mice developing carotid or intracranial aneurysms. The effect of SDF-1 on endothelial cells and macrophages was studied by chemotaxis cell migration assay and capillary tube formation assay. Anti-SDF-1 blocking antibody was given to mice and compared with control (vehicle)-administered mice for its effects on the walls of carotid aneurysms and the development of intracranial aneurysms., Results: Human aneurysms, murine carotid aneurysms, and murine intracranial aneurysms all expressed SDF-1, and mice with developing carotid or intracranial aneurysms had increased progenitor cells expressing CXCR4, the receptor for SDF-1 (p < 0.01 and p < 0.001, respectively). Human aneurysms and murine carotid aneurysms had endothelial cells, macrophages, and capillaries in the walls of the aneurysms, and the presence of capillaries in the walls of human aneurysms was associated with the presence of macrophages (p = 0.01). Stromal cell-derived factor-1 promoted endothelial cell and macrophage migration (p < 0.01 for each), and promoted capillary tube formation (p < 0.001). When mice were given anti-SDF-1 blocking antibody, there was a significant reduction in endothelial cells (p < 0.05), capillaries (p < 0.05), and cell proliferation (p < 0.05) in the aneurysm wall. Mice given anti-SDF-1 blocking antibody developed significantly fewer intracranial aneurysms (33% vs 89% in mice given control immunoglobulin G, respectively; p < 0.05)., Conclusions: These data suggest SDF-1 is associated with angiogenesis and inflammatory cell migration and proliferation in the walls of aneurysms, and may have a role in the development of intracranial aneurysms.

Introduction: Over the past several decades, checklists have emerged in a variety of different patient care settings to help reduce medical errors and ensure patient safety. To date, there have been no published accounts demonstrating the effectiveness of checklists designed specifically for the unique demands of neurointerventional procedures., Methods: A three-part, 20-item checklist was developed specific to neurointerventional procedures using the WHO surgical checklist as a template. Staff members (nurses, radiation technologists and physicians) were surveyed regarding near-miss adverse events and the quality of communication immediately following each neurointerventional procedure for 4 weeks prior to implementation of the checklist and again for 4 weeks after using the checklist. Staff members were asked to complete final surveys at the end of the study period., Results: 71 procedures were performed during the 4 weeks prior to checklist implementation and 60 procedures were performed during the 4 weeks after institution of the checklist. Post-checklist surveys indicated significantly improved communication compared with pre-checklist surveys (χ(2) 29.4, p<0.001). The number of adverse events was lower after checklist implementation for eight of the nine adverse event types (not individually significant), but the total number of adverse events was significantly lower after checklist implementation (χ(2) 11.4, p=0.001). Final staff surveys were uniformly positive with 95% of individuals indicating that the checklist should be continued in the department., Conclusions: Use of a neurointerventional procedural checklist resulted in statistically significant improvements in team communication and a significant reduction in total adverse events, with uniformly positive staff feedback.

Background: Untreated, moyamoya angiopathy is a progressive vaso-occlusive process that can lead to ischemic or hemorrhagic stroke., Objective: To review 1 institution's surgical experience with both direct and indirect bypass (encephaloduroarteriosynangiosis) in adult and pediatric groups., Methods: A retrospective review was conducted of a consecutive series of patients treated for moyamoya angiopathy between 1995 and 2009., Results: Thirty-nine adult patients underwent indirect bypass as their initial therapy; 29 adult patients underwent direct bypass. Twenty-four pediatric patients included 20 indirect bypasses and 4 direct bypasses. Overall, 140 hemispheres were treated; 48 patients received revascularization of both hemispheres. There were 14 additional revascularization procedures (10% per hemisphere) performed over a site of continued hypoperfusion postoperatively. Fourteen postoperative ischemic strokes occurred during the entire follow-up (10% per hemisphere), and the Kaplan-Meier analysis was not significantly different between groups (P = .59). Four grafts (9.09%) had failed at radiographic follow-up of the 44 direct bypasses performed. Before the initial surgery, the modified Rankin Scale score was 1.58 ± 0.93, 1.48 ± 0.74, and 1.8 ± 1.1 in the pediatric, adult direct, and adult indirect groups (P = .39). At last follow-up, it was 1.29 ± 1.31, 1.09 ± 0.90, and 1.94 ± 1.51 (P = .04) in the pediatric, adult direct, and adult indirect groups., Conclusion: This series demonstrates that both direct and indirect bypasses can be equally effective in preventing stroke. However, in adult patients, direct bypass patients had significantly greater improvement in symptoms, as seen in modified Rankin Scale scores. Pediatric patients, despite undergoing predominantly indirect bypasses, fared roughly the same as the adults in the direct bypass group.

The Stenting and Aggressive Medical Management for Preventing Recurrent stroke in Intracranial Stenosis (SAMMPRIS) trial, the first randomized trial to compare best medical therapies with angioplasty and stenting, was halted prematurely owing to a 30-day stroke rate of 14.7% in the angioplasty and stenting arm compared with 5.8% in the medical management arm. These results have led to a paradigm shift away from interventional therapies and back to dual antiplatelet therapy and aggressive medical therapies only for these patients. However, there appears to be a subset of patients with intracranial atherosclerotic disease (ICAD) who are different from the general SAMMPRIS cohort and are defined by flow failure from severe intracranial arterial stenosis resulting in recurrent ischemic symptoms despite maximal medical therapy. Offering the option of endovascular revascularization seems appropriate in this patient population, given their recurrent ischemic events regardless of aggressive medical therapies. This paper provides a rationale for reconsidering the role of interventional therapies in patients with critical intracranial stenosis and presents four patients with flow failure from ICAD and persistent symptoms of ischemia, regardless of dual antiplatelet and adjuvant medical therapies, who subsequently improved with angioplasty. Consideration of alternative patient populations and treatment paradigms seems to carry particular relevance now as the endovascular treatment of intracranial atheromatous disease is currently receiving intense scrutiny by those medical specialties involved in the care of stroke patients, as well as the public at large.

Large and giant aneurysms pose significant challenges to the endovascular techniques of coil embolization or parent vessel reconstruction. Many large aneurysms are wide-necked with bulbous domes and frequently require stent-assisted coiling or flow diversion to reconstruct and preserve flow through the parent artery. Often the wire must be looped in the dome before catheterization of the exiting portion of the parent vessel is possible. In addition, it can be challenging to obtain stable distal purchase of the microcatheter that will allow the loop to be withdrawn from the aneurysm without the entire microcatheter unwinding, resulting in herniation into the aneurysm or proximal vessels. The stent anchor technique, a novel method of obtaining distal purchase that allows straightening of the catheter loop within a large aneurysm for the purposes of stenting for vessel reconstruction across large or giant aneurysms, is presented. This technique may facilitate the use of new stent technologies in the treatment of large aneurysms that have traditionally been exceedingly difficult to treat via an endovascular approach.

Background: There is a growing body of literature supporting venous sinus stenosis as a causative etiology for many patients diagnosed with idiopathic intracranial hypertension. Recent series have documented improvement in the pre- and post-stenosis venous pressure gradient as well as clinical symptoms after stenting. Concomitant real time intracranial pressure (ICP) monitoring has not been previously described during venous sinus stenting., Case Report: A woman in her twenties presented with rapidly progressive visual loss and cranial neuropathies with an MRI revealing high grade right transverse sinus stenosis. Lumbar puncture demonstrated an opening pressure >55 cm H₂O. Her vision and cranial neuropathies continued to worsen despite ventriculoperitoneal shunting. A parenchymal ICP monitoring wire was placed, revealing ICP persistently >70 cm H₂O. She underwent venography and a pre- to post-stenosis pressure gradient of 55 mm Hg was measured. The patient underwent sinus stenting resulting in a near immediate reduction in her ICP from 70 to 20 cm H₂O within 30 s after deployment. Her ICP completely normalized within 24 h of stenting., Conclusions: A case is presented of severe intracranial hypertension with rapidly progressive neurologic decline despite CSF diversion secondary to venous sinus stenosis that resolved following venous sinus stenting. This is the first report of real time ICP monitoring during venous sinus stenting.

Introduction: There have been recent reports of high vascular complication rates after the use of the Mynx vascular closure device (VCD). At our institution, vascular complications due to these devices have rarely been encountered. A study was undertaken to retrospectively compare angiographic abnormalities seen after femoral artery closure by both the Mynx and AngioSeal VCDs to provide further insight into the risks associated with VCDs., Methods: All adult patients who underwent deployment of either a Mynx or AngioSeal VCD and subsequently underwent repeat angiography within the next 30 days between 1 July 2010 and 1 April 2011 were reviewed. Two independent blinded radiologists compared blinded pre-procedure and follow-up femoral angiograms for the presence of pseudoaneurysm or other vascular abnormality. Hospital records were reviewed for major or minor complications of the groin site or femoral artery., Results: Thirty patients (31 angiograms) underwent vascular closure with a Mynx and 57 patients (69 angiograms) received an AngioSeal. The average time elapse until repeat femoral angiography was 6.2 days (range 1-21, median 5.5 days) in the Mynx group and 6.3 days (range 0-30, median 5 days) in the AngioSeal group. Two pseudoaneurysms and one minor stenosis were identified in the AngioSeal group. No angiographic abnormalities were seen in the Mynx group. No intraluminal filling defects were demonstrated on any of the follow-up femoral angiograms. One patient who received an AngioSeal developed a delayed minor groin site hematoma that did not require surgical intervention., Conclusions: Angiographic complications were seen in only 3% of patients after closure with Mynx or AngioSeal VCDs. There were no clinically significant groin site or vascular complications. These data suggest that both VCDs are safe for use after angiography with a low rate of femoral artery complications.

Objective: Brown tumors are nonneoplastic lesions that occur only in the setting of hyperparathyroidism. Although vertebral brown tumors are relatively rare pathologic entities, their incidence seems to be on the rise, as evidenced by multiple case reports published during the past four decades. An extensive review of these lesions is lacking in the literature. We present a case of paraparesis secondary to vertebral brown tumor followed by a detailed review of the literature., Methods: We performed a review of the literature to locate all reported cases to date of vertebral brown tumors resulting in neurologic sequelae. In addition, we present the case of a 33-year-old female with end-stage renal disease and previous subtotal parathyroidectomy who presented with acute-onset paraparesis from an expansile L1 brown tumor and was treated successfully by laminectomy and bracing., Results: Thirty cases of vertebral brown tumor resulting in neurologic deficit were located in our literature search. Most occurred in women (63%), those aged 40 to 49 years (27%), and in the thoracic spine (57%). Lesions occurred roughly equally in primary (47%) and secondary (53%) hyperparathyroidism. Most patients demonstrated either symptomatic or radiographic improvement after neurosurgical intervention and/or subtotal or total parathyroidectomy., Conclusion: In patients presenting with a lytic vertebral lesion and known hyperparathyroidism or end-stage renal disease, brown tumor should be considered in the differential diagnosis. In select cases with minimal neurologic symptoms, parathyroidectomy may be warranted prior to neurosurgical intervention., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Background and Importance: Most neuroendovascular interventions rely on a transfemoral approach to the intracranial circulation; however, this is sometimes not possible because of complex aortic arch anatomy or femoral arterial disease. Transradial arteriography and intervention are well established in interventional cardiology, and there have been some reports of successful neurointervention using this technique. The incidence of radial artery occlusion or other access site complications after transradial access is directly related to the outer diameter of the sheath used to access the artery. We describe a novel approach to neuroendovascular intervention using a 070 Neuron guide catheter to directly access the radial artery for complex cerebrovascular intervention., Clinical Presentation: We describe a technique to directly access the radial artery with a 070 Neuron catheter, without the need for a large 6-French sheath, for cerebrovascular interventions. Two successful cases are described in which this technique was used. Case 1 describes the successful Y-stent placement for coiling of a basilar tip aneurysm, and case 2 describes coiling of a ruptured posterior inferior cerebellar artery aneurysm., Conclusion: The 070 Neuron catheter can be used in a direct access transradial approach to the cerebrovascular circulation for complex interventions without a radial sheath, thereby maximizing guide catheter diameter and minimizing the radial arteriotomy size.

Background: The pipeline embolization device (PED) is the latest technology available for intracranial aneurysm treatment., Objective: To report early postmarket results with the PED., Methods: This study was a prospective registry of patients treated with PEDs at 7 American neurosurgical centers subsequent to Food and Drug Administration approval of this device. Data collected included clinical presentation, aneurysm characteristics, treatment details, and periprocedural events. Follow-up data included degree of aneurysm occlusion and delayed (> 30 days after the procedure) complications., Results: Sixty-two PED procedures were performed to treat 58 aneurysms in 56 patients. Thirty-seven of the aneurysms (64%) treated were located from the cavernous to the superior hypophyseal artery segment of the internal carotid artery; 22% were distal to that segment, and 14% were in the vertebrobasilar system. A total of 123 PEDs were deployed with an average of 2 implanted per aneurysm treated. Six devices were incompletely deployed; in these cases, rescue balloon angioplasty was required. Six periprocedural (during the procedure/within 30 days after the procedure) thromboembolic events occurred, of which 5 were in patients with vertebrobasilar aneurysms. There were 4 fatal postprocedural hemorrhages (from 2 giant basilar trunk and 2 large ophthalmic artery aneurysms). The major complication rate (permanent disability/death resulting from perioperative/delayed complication) was 8.5%. Among 19 patients with 3-month follow-up angiography, 68% (13 patients) had complete aneurysm occlusion. Two patients presented with delayed flow-limiting in-stent stenosis that was successfully treated with angioplasty., Conclusion: Unlike conventional coil embolization, aneurysm occlusion with PED is not immediate. Early complications include both thromboembolic and hemorrhagic events and appear to be significantly more frequent in association with treatment of vertebrobasilar aneurysms.

Background: Giant posterior communicating artery (PCoA) aneurysms (> 25 mm) are rare lesions associated with a poor prognosis and high rates of morbidity and mortality., Objective: To review the clinical results of giant PCoA aneurysms surgically treated at our institution, focusing on operative nuances., Methods: All cases of giant PCoA aneurysms treated surgically at our institution were identified from a prospectively maintained patient database. Patient demographic factors, medical comorbidities, rupture status, neurological presentation, clinical outcomes, and surgical records were critically reviewed., Results: From 1989 to 2010, 11 patients (10 women) underwent surgical clipping of giant PCoA aneurysms. Presenting signs and symptoms included cranial nerve palsies, diminished mental status, headache, visual changes, and seizures. Five aneurysms were ruptured on admission. All aneurysms were clipped primarily except 1, which was treated by parent artery sacrifice and extracranial-to-intracranial bypass after intraoperative aneurysm rupture. Perioperative morbidity and mortality rates were 36% (4 of 11) and 18.3% (2 of 11), respectively. Excellent or good clinical outcomes, defined as modified Rankin Scale scores ≤ 2, were achieved in 86% (5 of 6) of patients available for long-term clinical follow-up (mean, 12.5 ± 13.6 months)., Conclusion: Giant PCoA aneurysms are rare vascular lesions that may present with a variety of neurological signs and symptoms. These lesions can be successfully managed surgically with satisfactory morbidity and mortality rates. To the best of our knowledge, this is the largest surgical series of giant PCoA aneurysms published to date.

The pipeline embolization device has demonstrated clinical success in the management of complex intracranial aneurysms arising along the anterior intracranial circulation with a relatively low complication profile. A case report is presented which describes a novel complication of delayed intraparenchymal hemorrhage following deployment of a pipeline embolization device for the treatment of a previously ruptured partially thrombosed ophthalmic segment aneurysm.

Object: Intramedullary, or glomus, spinal arteriovenous malformations (AVMs) are rare vascular lesions amenable to resection with or without adjuvant embolization. The authors retrospectively reviewed the senior author's (R.F.S.'s) surgical series of intramedullary spinal AVMs to evaluate clinical and radiographic outcomes., Methods: Detailed chart and radiographic reviews were performed for all patients with intramedullary spinal AVMs who underwent surgical treatment between 1994 and 2011. Presenting and follow-up neurological examination results were obtained and graded using the modified Rankin Scale (mRS) and McCormick Scale. Surgical technique, outcomes, complications, and long-term angiographic studies were reviewed., Results: During the study period, 20 patients (10 males and 10 females) underwent resection of glomus spinal AVMs. The mean age at presentation was 30 ± 17 years (range 7-62 years). The location of the AVMs was as follows: cervical spine (n = 10), thoracic spine (n = 9), and cervicothoracic junction (n = 1). The most common presenting signs and symptoms included paresis or paralysis (65%), paresthesias (40%), and myelopathy (40%). Perioperative embolization was performed in the majority (60%) of patients. Pial AVM resection was performed in 17 cases (85%). Angiographically verified AVM obliteration was achieved in 15 patients (75%). At a mean follow-up duration of 45.4 ± 52.4 months (range 2-176 months), 14 patients (70%) remained functionally independent (mRS and McCormick Scale scores ≤ 2). One perioperative complication occurred, yielding a surgical morbidity rate of 5%. Three symptomatic spinal cord tetherings occurred at a mean of 5.7 years after AVM resection. No neurological decline was observed after endovascular and surgical interventions. No deaths occurred. Long-term angiographic follow-up data were available for 9 patients (40%) at a mean of 67.6 ± 60.3 months (range 5-176 months) following AVM resection. Durable AVM obliteration was documented in 5 (83%) of 6 patients., Conclusions: Intramedullary AVMs may be safely resected with satisfactory clinical and angiographic results. The pial resection technique, which provides subtotal AVM nidus resection, effectively devascularized these lesions, as confirmed on postoperative angiography, without violating the spinal cord parenchyma, thereby potentially reducing iatrogenic injury.

Objective: Cerebral venous sinus thrombosis (CVST) is a rare cause of stroke. A 21 year-old female presented to our institution in a rapidly deteriorating neurological state following failed systemic heparin therapy for treatment of superior sagittal sinus (SSS) thrombosis., Methods: The patient underwent emergent mechanical thrombectomy of the thrombosed SSS using the 0.054-inch Penumbra catheter. No adjuvant direct pharmacologic and/or mechanical thrombectomy was performed., Results: Successful venous recanalization was achieved using the Penumbra system. The patient improved symptomatically following the intervention, and she made a complete neurological recovery within 30 days. At 6-month follow-up, the patient had returned to work and school and remained neurologically intact. A repeat MRV showed complete sinus recanalization., Conclusion: Direct mechanical thrombectomy using the Penumbra system provided rapid sinus recanalization for the treatment of symptomatic cerebral venous sinus thrombosis. This device is a valuable addition to the neurointerventional armamentarium., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Percutaneous vascular closure devices are being increasingly used as alternatives to manual compression for the closure of femoral arteriotomy after endovascular procedures as they appear to reduce time to ambulate, improve patient's comfort, and are implicated with cost saving. However, vascular closure devices have been associated with an increased risk of complications including hematoma formation, local bleeding, arteriovenous fistula formation, pseudoaneurysm and arterial leg ischemia. To our knowledge, if the above complications occur it is usually within the first 30 days after the procedure. None have been reported in a delayed fashion ten months or longer after closure. We describe a 30-year-old man with a history of a giant basilar trunk aneurysm. He was placed on aspirin and clopidogrel prior to the procedure. He had bilateral femoral access with 6 French sheaths. Following the procedure, 6 French Angio-Seals (St. Jude Medical, St. Paul, MN, USA) were used for closure of bilateral femoral arteriotomies. Ten months after the procedure, the patient kicked a metal cart and developed a large right retroperitoneal iliopsoas hematoma. There was no evidence of pseudoaneurysm. The patient was managed conservatively and his serial hematocrit stayed stable. He did not require surgical intervention. Use of percutaneous vascular closure devices is associated with complications including risk of hematoma, pseudoaneurysm, intravenous fistula, rectal peritoneal hemorrhage, limb ischemia and possible surgical repair. Most complications occur peri-procedure or within 30 days post-procedure. This is the first reported case of a delayed complication at ten months after the initial procedure. Site-related complications associated with percutaneous vascular closure devices may occur in a delayed fashion, even ten months post-procedure, so should be considered in the management of patients.

Background: Intravascular stents have been applied to treat a variety of pathophysiologic conditions. With advances in stent design and delivery, stenting has become a viable treatment option in neurovascular disease. Recently, intracranial arterial stenting has received increasing interest as a modality to rapidly and effectively recanalize affected vessels in the setting of acute ischemic stroke., Methods: To examine the potential of stenting procedures for stroke, we compiled and analyzed relevant experimental and clinical studies in the available databases., Results: Our resulting discussion covers the brief history of stents, from their initial inception in the 1960s, to the developments of interventional cardiology, and finally to the treatment of acute occlusions of the neurovasculature. We also detail technological advances that have improved stent delivery to intracranial arteries and review the several clinical studies that feature stenting for the treatment of acute ischemic stroke., Conclusion: Numerous clinical studies have revealed that stents are a quick and efficacious endovascular tool for acute ischemic stroke treatment. It appears likely that issues regarding design, safety, and feasibility of stent-based devices will experience further improvement and refinement, and from fruitful criticism of existing technologies and techniques, along with lessons from past mistakes, will arise safer and more effective devices., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Objective: Cerebral vasospasm is a major source of morbidity and mortality following aneurysmal subarachnoid hemorrhage (SAH). A variety of therapies have been utilized to prevent or treat vasospasm. Despite the large number of clinical trials, few randomized controlled trials (RCTs) of sufficient quality have been published. We review the RCTs and meta-analyses in the literature regarding the treatment and prevention of cerebral vasospasm following aneurysmal SAH., Methods: A literature search of MEDLINE, the Cochrane Controlled Trials Registry, and the National Institutes of Health/National Library of Medicine clinical trials registry was performed in January 2010 using predefined search terms. These trials were critically reviewed and categorized based on therapeutic modality., Results: Forty-four RCTs and 9 meta-analyses met the search criteria. Significant findings from these trials were analyzed. The results of this study were as follows: nimodipine demonstrated benefit following aneurysmal SAH; other calcium channel blockers, including nicardipine, do not provide unequivocal benefit; triple-H therapy, fasudil, transluminal balloon angioplasty, thrombolytics, endothelin receptor antagonists, magnesium, statins, and miscellaneous therapies such as free radical scavengers and antifibrinolytics require additional study. Tirilazad is ineffective., Conclusions: There are many possible successful treatment options for preventing vasospasm, delayed ischemic neurologic deficits, and poor neurologic outcome following aneurysmal subarachnoid hemorrhage; however, further multicenter RCTs need to be performed to determine if there is a significant benefit from their use. Nimodipine is the only treatment that provided a significant benefit across multiple studies., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Cerebral vasospasm and delayed cerebral ischemia account for significant morbidity and mortality after aneurysmal subarachnoid hemorrhage. While most patients are managed with triple-H therapy, endovascular treatments have been used when triple-H treatment cannot be used or is ineffective. An electronic literature search was conducted to identify English language articles published through October 2010 that addressed endovascular management of vasospasm. A total of 49 articles were identified, addressing endovascular treatment timing, intra-arterial treatments, and balloon angioplasty. Most of the available studies investigated intra-arterial papaverine or balloon angioplasty. Both have generally been shown to successfully treat vasospasm and improve neurological condition, with no clear benefit from one treatment compared with another. There are reports of complications with both therapies including vessel rupture during angioplasty, intracranial hypertension, and possible neurotoxicity associated with papaverine. Limited data are available evaluating nicardipine or verapamil, with positive benefits reported with nicardipine and inconsistent benefits with verapamil.

There has been a substantial increase in the number of neuroendovascular procedures performed over the last 15 years. Although rare, complications of cerebral angiography and neuroendovascular procedures have the potential to be devastating. Fortunately, dedication to careful patient selection, meticulous attention to technical detail, and standardization of endovascular treatment protocols results in an acceptably low complication rate. Factors that may predispose one to complications with cerebral angiography include age, smoking, functional stats, medical comorbidities, and duration of the procedure. The most common complication of angiography is vascular access site complication, with a rate of up to 5%. The overall neurologic complication rate for diagnostic angiography is 1.3-2.6%, with a permanent neurologic deficit rate of 0.14-0.50%. Neuroendovascular interventions are more invasive, take longer to perform, and have higher rates of complication. Procedure specific complications include aneurysm rupture, arterial dissection, stroke, hemorrhage, thromboembolism, and microembolism, and rates of neurologic deficit are higher than those for diagnostic angiography. With knowledge of the common complications, strategies to minimize them, and a meticulous attention to the technical detail of the procedure, complications of neuroendovascular interventions can be minimized.

Stroke patients whose condition does not improve after intravenous administration of tissue plasminogen activator (tPA) may be candidates for endovascular intervention. Patients with new intracerebral hemorrhage noted during such interventions pose a difficult challenge to neurointerventionists and are often sequestered as treatment failures and deemed inappropriate for intraarterial recanalization efforts. The authors present a case in which aggressive intervention was performed despite evidence of contrast extravasation on preintervention angiography. This 37-year-old woman presented with an occlusion of the M(1) segment of the left middle cerebral artery and a National Institutes of Health Stroke Scale score of 24. She received intravenous tPA without improvement. Angiography revealed M(1) thrombus as well as active contrast extravasation without arterial displacement. Thromboaspiration was performed in light of her known hemorrhage with excellent recanalization. Immediate postprocedure imaging demonstrated a large insular hematoma and emergent craniectomy and hematoma evacuation were performed. At 4 months' follow-up, the patient was living at home, was ambulating, and had excellent comprehension with mild expressive aphasia. There is little peer-reviewed data in the literature to aid in the decision-making process when contrast extravasation is recognized at the time of preinterevention angiography. Continuation of mechanical endovascular stroke intervention, in light of active contrast extravasation, may be warranted in young patients with major deficits and absence of arterial displacement or delayed global filling. Further thrombolytics are not advised. In select stroke patients, continuation of a planned attempt at mechanical recanalization without the further use of thrombolytics may be warranted in light of known intracerebral hemorrhage.

Objective: The International Cooperative Study on the Timing of Aneurysm Surgery demonstrated that subarachnoid hemorrhage (SAH) patients who underwent surgery on post-hemorrhage days 4-10 had worse outcomes than patients treated on days 0-3 and days 11-14. Based on these findings, it was concluded that patients who present with SAH on days 4-10 should have aneurysm surgery delayed until after day 10. Since the study, coiling has become a treatment option and it is unclear whether these results apply to this new treatment modality. Our institution is a regional referral center for SAH, and patients are transferred at different time points after hemorrhage. We wanted to determine whether patients that arrive on days 4-10 were safe to undergo coiling immediately rather than waiting until after day 10., Methods: We reviewed 119 consecutive SAH patients who underwent coiling between January 2006 and June 2008. Factors of age, gender, Hunt-Hess grade, Fisher score, aneurysm size and aneurysm location were included in a regression analysis to determine the effect of day of coiling on clinical outcome at discharge., Results: Of 119 study patients, 86% had coiling on post-hemorrhage days 0-3, and 12% on days 4-10. Patients in these cohorts did not differ in any demographic factors. Age and Hunt-Hess grade were the only predictors of mortality (age p=0.0001, Hunt-Hess p=0.0110) and poor outcome, defined as death or discharge to a skilled nursing facility (age p=0.0001, Hunt-Hess p=0.0001). Day of coiling had no effect on mortality (p=0.5731) or poor outcome (p=0.1861)., Conclusions: Coiling of ruptured aneurysms can be performed safely on patients who arrive on post-hemorrhage days 4-10, and treatment need not be delayed after day 10, as the results of the Timing of Aneurysm Surgery Study initially suggested.

Background: Although there are several large-species animal models for saccular aneurysms, there is a need for a simple, reproducible saccular aneurysm model in mice., Objective: To develop a murine saccular aneurysm model, which replicates key characteristics that occur in the formation of human cerebral aneurysms., Methods: Elastase is applied extravascularly to the right common carotid artery. We induced saccular aneurysm formation by our method in C57BL/6 mice (n = 30). Aneurysms and control arteries (left common carotid arteries) were harvested at 1 week, 2 weeks, and 3 weeks postinjury (n = 10 for each time point), measured, and stained for elastin content. To demonstrate BMP-derived cell recruitment to the aneurysms, bone marrow from UBC-gfp transgenic mice was transplanted into irradiated C57BL/6 recipients to create C57BL/6.gfp chimeras. Additionally, bone marrow from DsRed transgenic mice was transplanted into irradiated C57BL/6 recipients to create C57BL/6.DsRed chimeras, and bone marrow from B5/EGFP transgenic mice was transplanted into irradiated FVB recipients to create FVB.gfp chimeras. The elastase injury or sham operations were performed in the C57BL/6.gfp, C57BL/6.DsRed, and FVB.gfp chimeras. Aneurysms and sham vessels were harvested at 3 weeks and examined for BMP-derived cell recruitment. Additionally, aneurysms were stained for matrix metalloproteinase-9, which is overexpressed in human cerebral aneurysm tissue., Results: Aneurysms consistently demonstrated significant loss of elastin in the vessel wall and had significantly larger diameters than control vessels (591 +/- 238 microm vs 328 +/- 61 microm; P = .003 for aneurysms 3 weeks postinjury). Aneurysms from C57BL/6.gfp, FVB.gfp, and C57BL/6.DsRed chimeras consistently revealed significant BMP-derived cell recruitment in the aneurysm wall that was not seen in sham-operated vessels nor in control left common carotid arteries. Aneurysms demonstrated overexpression of matrix metalloproteinase-9., Conclusion: We describe a novel murine elastase saccular aneurysm model that replicates the histopathology and BMP-derived cell-mediated processes that will be a valuable instrument for studying the cell-mediated processes in cerebral aneurysm formation.

Acute intracranial stroke is a major source of morbidity and mortality in the United States. Recent studies have shown improved clinical outcomes for patients who achieve timely arterial recanalization. Multimodal therapies have evolved to meet this end point and include intravenous and/or intra-arterial thrombolysis and mechanical thrombolysis. Modifications to existing balloon-mounted stents commonly used in cardiology have yielded more easily navigable and safer self-expanding intracranial stents that provide rapid arterial recanalization. We review the evolution of acute stroke therapy over the past few decades and the recent results of mechanical thrombolysis, focusing on intracranial stenting in the setting of acute stroke.

Summary: Selective microcatheterization of intracranial aneurysms during coiling can be limited by tortuous vasculature. Stabilization of the microcatheter via distal placement of the guide catheter in the intracranial vasculature may cause vessel dissection or vasospasm. We describe the application of an intermediate sized bridging catheter in four patients with tortuous vasculature who underwent successful coiling of ruptured aneurysms. No complications occurred. The intermediate sized bridging catheter is a useful adjunct for navigation of tortuous parent artery vasculature.

Cerebral venous sinus thrombosis (CVST) is an increasingly diagnosed disease with a wide range of symptoms, ranging from a mild headache to cerebral herniation. A potentially devastating syndrome, CVST has been associated with a mortality rate of 6-10%. In prospective studies, the overall rate of death and dependency from CVST ranges from 8.8 to 44.4%. Systemic anticoagulation remains the first-line treatment. However, a percentage of patients deteriorate despite medical therapy. These cases have resulted in the development of thrombolysis or endovascular treatment for CVST. Initial reports of the use of endovascular treatment of CVST have been promising. However, enthusiasm for the use of endovascular thrombolysis and thrombectomy should be tempered by an understanding of possible risks such as intracerebral hemorrhage and/or vessel dissection. The authors review the literature regarding endovascular treatment of CVST with a description of the chemical and mechanical thrombolytic techniques.

Objective: Antiplatelet therapy is critical to endovascular neurosurgical procedures. Some patients are aspirin-resistant nonresponders. We reviewed our endovascular neurosurgery patients who were premedicated with aspirin and clopidogrel and identified nonresponders to aspirin. Factors associated with aspirin resistance were determined., Methods: Consecutive endovascular neurosurgery patients were identified who were treated by the senior author (BLH) from December 2006 to October 2007 and who were premedicated with aspirin (325 mg) and clopidogrel (75 mg) for 7 days before the procedure. We retrospectively reviewed values from the platelet function analyzer-100 test (Dade-Behring, Deerfield, IL) from 1 day before the procedures. The following factors were evaluated for association with aspirin drug resistance: age, sex, body mass index, and smoking history; patients with hypertension, diabetes, coronary artery disease/ peripheral vascular disease, or hypercholesterolemia; disease pathology (aneurysm, intracranial stenosis, or extracranial stenosis); patients taking statins, beta-blockers, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, or antidepressants; and white blood cell count, hemoglobin, hematocrit, and platelet levels. A stepwise logistic model selection was used to select important factors and their interactions., Results: Eighty-one consecutive patients with the following interventions were included in the study: 35 aneurysm coilings (43%), 21 stent-assisted aneurysm coilings (26%), 13 carotid stent and angioplasties (16%), 7 intracranial stents and angioplasties (9%), and 5 extracranial vertebral artery stents and angioplasties (6%). Seventeen patients (21%) were nonresponders to aspirin. After model selection, the only factor associated with aspirin resistance was not taking an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker (P = 0.0348; odds ratio, 0.214; 95% confidence interval, 0.051-0.896)., Conclusion: Twenty-one percent of patients premedicated with aspirin and clopidogrel dual therapy for 7 days before endovascular neurosurgical procedures were nonresponders to aspirin. Patients not taking an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker may be at higher risk for aspirin drug resistance.

Objective: Intracranial arteriovenous malformations (AVM) may be managed through staged preoperative embolization and resection. Two commonly used liquid embolics are N-butyl cyanoacrylate (nBCA; Cordis Microvascular, Inc., New Brunswick, NJ) and Onyx (ev3, Inc., Irvine, CA). We sought to compare the utility of these agents in terms of fluoroscopy and procedure times., Methods: All intracranial AVMs embolized from 2002 to 2006 at the University of Florida were included in this study. Patients were stratified into three treatment groups: nBCA, Onyx, and patients who received both nBCA and Onyx during separate embolizations. Cohorts were compared by sex, age, Spetzler-Martin grade, AVM volume, fluoroscopy time, procedure time, surgical blood loss, and complications., Results: A total of 182 embolizations were performed on 88 patients (nBCA, 60 patients and 106 procedures; Onyx, 20 patients and 43 procedures; and nBCA/Onyx, eight patients and 16 nBCA and 17 Onyx procedures). There were no significant differences in patient demographics, AVM volumes, and Spetzler-Martin grades. Mean fluoroscopy and procedure times were increased for Onyx (57 min; 2.6 h) compared with nBCA (37 min; 2.1 h) embolizations (P < 0.0001 and P = 0.001, respectively). Cumulative mean fluoroscopy time was increased for Onyx (135 min) and nBCA/Onyx (180 min) cohorts relative to nBCA (64 min; P < 0.0001). Cumulative mean procedure time was increased in the nBCA/Onyx group (10.4 h) compared with nBCA (3.7 h) and Onyx (5.4 h; P < 0.0001). Seventy patients (80%) underwent AVM resection. No significant differences in surgical blood loss or complication rates were observed among the cohorts., Conclusion: Onyx AVM embolization requires increased fluoroscopy and procedure times compared with nBCA. Further investigation is necessary to justify increased radiation exposure and procedure time associated with Onyx.

Objective: Determining factors predictive of the natural risk of rupture of cerebral aneurysms is difficult because of the need to control for confounding variables. We studied factors associated with rupture in a study model of patients with multiple cerebral aneurysms, one aneurysm that had ruptured and one or more that had not, in which each patient served as their own internal control., Methods: We collected aneurysm location, one-dimensional measurements, and two-dimensional indices from the computed tomographic angiograms of patients in the proposed study model and compared ruptured versus unruptured aneurysms. Bivariate statistics were supplemented with multivariable logistic regression analysis to model ruptured status. A total of 40 candidate models were evaluated for predictive power and fit with Wald scoring, Cox and Snell R2, Hosmer and Lemeshow tests, case classification counting, and residual analysis to determine which of the computed tomographic angiographic measurements or indices were jointly associated with and predictive of aneurysm rupture., Results: Thirty patients with 67 aneurysms (30 ruptured, 37 unruptured) were studied. Maximum diameter, height, maximum width, bulge height, parent artery diameter, aspect ratio, bottleneck factor, and aneurysm/parent artery ratio were significantly (P < 0.05) associated with ruptured aneurysms on bivariate analysis. When best subsets and stepwise multivariable logistic regression was performed, bottleneck factor (odds ratio = 1.25, confidence interval = 1.11-1.41 for every 0.1 increase) and height-width ratio (odds ratio = 1.23, confidence interval = 1.03-1.47 for every 0.1 increase) were the only measures that were significantly predictive of rupture., Conclusion: In a case-control study of patients with multiple cerebral aneurysms, increased bottleneck factor and height-width ratio were consistently associated with rupture.

Object: Aneurysmal subarachnoid hemorrhage (ASAH) is a serious event with grave consequences. Delayed ischemic neurological deficits caused by cerebral arterial vasospasm contribute significantly to death and disability. Biomarkers may reflect brain injury and provide an early warning of impending neurological decline and stroke from ASAH-induced vasospasm. Alpha-II spectrin is a cytoskeletal protein whose breakdown products are candidate surrogate markers of injury magnitude, treatment efficacy, and outcome. In addition, all spectrin breakdown products (SBDPs) can provide information on the proteolytic mechanisms of injury., Methods: Twenty patients who received a diagnosis of Fisher Grade 3 ASAH were enrolled in this study to examine the clinical utility of SBDPs in the detection of cerebral vasospasm in patients with ASAH. All patients underwent placement of a ventriculostomy for continual cerebrospinal fluid drainage within 72 hours of ASAH onset. Cerebrospinal fluid samples were collected every 6 hours and analyzed using Western Blotting for SBDPs. Onset of vasospasm was defined as an acute onset of a focal neurological deficit or a change in Glasgow Coma Scale score of two or more points. All suspected cases of vasospasm were confirmed on imaging studies., Results: Both calpain- and caspase-mediated SBDP levels are significantly increased in patients suffering ASAH. The concentration of SBDPs was found to increase significantly over baseline level up to 12 hours before the onset of cerebral arterial vasospasm., Conclusions: Differential expression of SBDPs suggests oncotic necrotic proteolysis may be predominant in acute brain injury after ASAH and cerebral arterial vasospasm.

Background: Bow Hunter's syndrome is a rare form of vertebrobasilar insufficiency that may be successfully treated by surgical intervention. Use of intraoperative dynamic transcranial Doppler ultrasound for surgical treatment of vertebrobasilar insufficiency has been described in literature. However, this technique was inconsistent and unreliable in some patients. We present a case of a patient with Bow Hunter's syndrome treated surgically and emphasize the valuable addition of intraoperative dynamic angiography to determine resolution of vertebral artery compromise., Case Description: The patient was a 58-year-old man with complaints of dizziness, vertigo, and near-syncopal episodes that occurred when he rotated his head to the left. Imaging revealed compromise of the dominant left vertebral artery with leftward head rotation. An anterior cervical approach with decompression of the left subaxial vertebral artery was performed. Significant osteophyte formation was observed. Removal of bone and decompression of the vertebral artery was performed. Intraoperative dynamic angiography confirmed resolution of vertebral artery compression and minimized the amount of decompression. No further intervention was required., Conclusion: Intraoperative dynamic angiography is a definitive test to determine hemodynamic resolution of Bow Hunter's syndrome. It offers real-time feedback of vertebral artery decompression, potentially minimizes the amount of decompression, and can be performed safely.

Background: Recently, a great interest has emerged regarding the use of abciximab for treatment of stroke. Thromboembolic events that occur during neuroendovascular procedures represent a unique subset of stroke patients because definitive angiographic diagnosis and treatment can be performed immediately. The existing literature on this situation suggests excellent results; however, most publications are case reports, and the largest series is 13 cases. We report our experience using abciximab in the treatment of acute thromboembolic events that occur during neuroendovascular procedures., Methods: We reviewed the last 1373 consecutive patients who underwent neuroendovascular procedures at the University of Florida from our prospectively maintained clinical database. Of these patients, 29 (2.11%) endovascular cases were complicated by acute cerebral thromboembolic events that were treated with abciximab. Abciximab was administered in less than 1 hour after the onset of the occlusion in every patient. The Thrombolysis In Myocardial Infarction (TIMI) scale was used to measure immediate angiographic outcome, and the Modified Rankin Scale (MRS) was used to measure clinical outcome at the time of follow-up. Independent outcome was defined as an MRS of 3 or less at follow-up., Results: Angiographic improvement in the TIMI grade was achieved in 29 (81%) of 36 arteries. Three intracerebral hemorrhages occurred with abciximab when administered with concurrent mechanical clot disruption; in two of these hemorrhages, recombinant tissue plasminogen activator (r-tPA) was also administered. The mean follow-up time for the living cohort was 7.54 months. Twenty-four (83%) patients were independent at follow-up, 3 (10%) were dependent at follow-up, and 2 (7%) died., Conclusion: Abciximab appears to be safe and effective in the treatment of acute cerebral thromboembolic complications during neuroendovascular procedures.