C. Michael Cawley

Recommendations for Comprehensive Stroke Centers: A Consensus Statement From the Brain Attack Coalition

Background and Purpose— To develop recommendations for the establishment of comprehensive stroke centers capable of delivering the full spectrum of care to seriously ill patients with stroke and cerebrovascular disease. Recommendations were developed by members of the Brain Attack Coalition (BAC), which is a multidisciplinary group of members from major professional organizations involved with the care of patients with stroke and cerebrovascular disease. Summary of Review— A comprehensive literature search was conducted from 1966 through December 2004 using Medline and Pub Med. Articles with information about clinical trials, meta-analyses, care guidelines, scientific guidelines, and other relevant clinical and research reports were examined and graded using established evidence-based medicine approaches for therapeutic and diagnostic modalities. Evidence was also obtained from a questionnaire survey sent to leaders in cerebrovascular disease. Members of BAC reviewed literature related to their field and graded the scientific evidence on the various diagnostic and treatment modalities for stroke. Input was obtained from the organizations represented by BAC. BAC met on several occasions to review each specific recommendation and reach a consensus about its importance in light of other medical, logistical, and financial factors. Conclusions— There are a number of key areas supported by evidence-based medicine that are important for a comprehensive stroke center and its ability to deliver the wide variety of specialized care needed by patients with serious cerebrovascular disease. These areas include: (1) health care personnel with specific expertise in a number of disciplines, including neurosurgery and vascular neurology; (2) advanced neuroimaging capabilities such as MRI and various types of cerebral angiography; (3) surgical and endovascular techniques, including clipping and coiling of intracranial aneurysms, carotid endarterectomy, and intra-arterial thrombolytic therapy; and (4) other specific infrastructure and programmatic elements such as an intensive care unit and a stroke registry. Integration of these elements into a coordinated hospital-based program or system is likely to improve outcomes of patients with strokes and complex cerebrovascular disease who require the services of a comprehensive stroke center.

Evolution of the management of tentorial dural arteriovenous malformations

OBJECTIVETentorial dural arteriovenous malformations (DAVMs) are uncommon lesions associated with an aggressive natural history. Controversy exists regarding their optimal treatment. We present a single-institution series of tentorial DAVMs treated during a 12-year period, address the current controversies, and present the rationale for our current therapeutic strategy. METHODSTwenty-two patients with tentorial DAVMs were treated between 1988 and 2000. Treatment consisted of transarterial or transvenous embolization, surgical resection, disconnection of venous drainage, or a combination of these therapies. The clinical presentations, radiological features, treatment strategies, and results were studied. RESULTSEighteen patients (82%) presented with intracranial hemorrhage or progressive neurological deficits. Retrograde leptomeningeal venous drainage was documented in 22 cases (100%), classifying the lesions as Borden Type III. Angiographic follow-up monitoring was performed for 0 to 120 months and clinical follow-up monitoring for 1 to 120 months. Posttreatment angiography demonstrated obliteration in 22 cases (100%). Two patients experienced neurological decline after endovascular treatment and died. All of the 20 surviving patients exhibited clinical improvement; there were no episodes of rehemorrhage or new neurological deficits. Outcomes were excellent in 17 cases (77%), good in 2 cases (9%), and fair in 1 case (5%), and there were 2 deaths (9%). CONCLUSIONTentorial DAVMs are aggressive lesions that require prompt total angiographic obliteration. Disconnection of the venous drainage from the fistula may be accomplished with transarterial embolization to the venous side, transvenous embolization, or surgical disconnection of the fistula. We think that extensive nidal resections carry more risk and are unnecessary. We do not think there is a role for stereotactic radiosurgery in the treatment of these lesions.

Neurosurgical management of intracranial aneurysms previously treated with endovascular therapy.

OBJECTIVEWith the increased use of endovascular therapy, an increasing number of patients with incompletely treated intracranial aneurysms are presenting for further surgical management. This study reviews our experiences with such patients. METHODSDuring a 7-year period, 38 patients with 40 intracranial aneurysms who were initially treated with endovascular therapy underwent surgical obliteration of refractory or recurrent lesions. All patients were recorded in a prospective registry, and their clinical data and imaging studies were analyzed retrospectively. RESULTSTwenty-six anterior and 14 posterior circulation aneurysms were treated. Four aneurysms were on the cavernous internal carotid artery, 13 were on the distal internal carotid artery, 6 were on the anterior communicating artery complex, 2 were on the middle cerebral artery, 3 were on the posteroinferior cerebellar artery, 1 was at the vertebrobasilar junction, 3 were on the superior cerebellar artery, 4 were at the basilar apex, 2 were on the posterior cerebral artery, and 1 was on the distal vertebral artery. Two pseudoaneurysms—one on the petrocavernous segment of the internal carotid artery and one on the distal VA—also were treated. The median time until recurrence was 6 months. Thirty-one aneurysms were clip-ligated, and six were treated with trapping. Three extracranial-intracranial bypasses were performed. One aneurysm was treated with muslin wrapping. Two aneurysms required the use of surgical approaches that involved hypothermic circulatory arrest. Nine aneurysms required coil mass extraction and/or complex vascular reconstruction to complete lesion obliteration. All aneurysms except the single wrapped aneurysm were successfully excluded from the intracranial circulation. Two deaths occurred as a result of the operative procedures, and another patient died as a result of subarachnoid hemorrhage-induced massive myocardial infarction. Ultimately, 86.8% of patients achieved an excellent or good recovery. CONCLUSIONWith endovascular therapy assuming an increasing role in the treatment of patients with intracranial aneurysms, more lesions that are refractory to initial treatment will require surgical management. Our experience indicates that good results are attainable, although technical challenges are frequently encountered.

Effect of antiplatelet therapy and platelet function testing on hemorrhagic and thrombotic complications in patients with cerebral aneurysms treated with the pipeline embolization device: a review and meta-analysis.

Purpose The pipeline embolization device (PED) necessitates dual antiplatelet therapy (APT) to decrease thrombotic complications while possibly increasing bleeding risks. The role of APT dose, duration, and response in patients with hemorrhagic and thromboembolic events warrants further analysis. Methods A PubMed and Google Scholar search from 2009 to 2014 was performed using the following search terms individually or in combination: pipeline embolization device, aneurysm(s), and flow diversion, excluding other flow diverters. Review of the bibliographies of the retrieved articles yielded 19 single and multicenter studies. A statistical meta-analysis between aspirin (ASA) dose (low dose ≤160 mg, high dose ≥300 mg), loading doses of APT agents, post-PED APT regimens, and platelet function testing (PFT) with hemorrhagic or thrombotic complications was performed. Results ASA therapy for ≤6 months post-PED was associated with increased hemorrhagic events. High dose ASA ≤6 months post-PED was associated with fewer thrombotic events compared with low dose ASA. Post-PED clopidogrel for ≤6 months demonstrated an increased incidence of symptomatic thrombotic events. Loading doses of ASA plus clopidogrel demonstrated a decreased incidence of permanent symptomatic hemorrhagic events. PFT did not show a statistically significant relationship with symptomatic hemorrhagic or thrombotic complications. Conclusions High dose ASA >6 months is associated with fewer permanent thrombotic and hemorrhagic events. Clopidogrel therapy ≤6 months is associated with higher rates of thrombotic events. Loading doses of ASA and clopidogrel were associated with a decreased incidence of hemorrhagic events. PFT did not have any significant association with symptomatic events.

Treatment of complex anterior cerebral artery aneurysms with Pipeline flow diversion: mid-term results

Background The off-label use of flow diverters in the treatment of distal aneurysms continues to be debated. Objective To report our multicenter experience in the treatment of complex anterior cerebral artery aneurysms with the Pipeline embolization device (PED). Methods The neurointerventional databases of the four participating institutions were retrospectively reviewed for aneurysms treated with PED between October 2011 and January of 2016. All patients treated for anterior cerebral artery aneurysms were included in the analysis. Clinical presentation, location, type, vessel size, procedural complications, clinical and imaging follow-up were included in the analysis. Results Twenty patients (13 female) with 20 aneurysms met the inclusion criteria in our study. Fifteen aneurysms were classified as saccular and five as fusiform (mean size 7.3 mm). Thirteen aneurysms were located in the anterior communicating region (ACOM or A1/2 junction), six were A2-pericallosal, and one was located in the A1 segment. Six patients had presented previously with subarachnoid hemorrhage and had their aneurysms initially clipped or coiled. There was one minor event (a small caudate infarct) and one major event (intraparenchymal hemorrhage). Sixteen of the 20 patients had angiographic follow-up (mean 10 months). Eleven aneurysms were completely occluded, one had residual neck, and four had residual aneurysm filling. Conclusions The treatment of complex anterior cerebral artery aneurysms with the PED as an alternative for patients who are not good candidates for conventional methods is technically feasible and safe. Mid-term results are promising but larger series with long-term follow-up are required to assess its effectiveness.

Microsurgical and endovascular management of pericallosal aneurysms.

Background Pericallosal, or A2 bifurcation, aneurysms are an infrequently encountered cause of subarachnoid hemorrhage (SAH). While the International Subarachnoid Aneurysm Trial showed improved outcomes for patients with any ruptured anterior circulation aneurysm treated with embolization, there was also a higher recurrence rate for embolized aneurysms. Notably, there were relatively few pericallosal aneurysms. Objective Specific analysis of pericallosal aneurysms may help guide therapeutic decisions. Methods Retrospective analysis of patients who presented with proven saccular pericallosal aneurysms was performed at two institutions from 1999 to 2009. Patients were stratified according to presentation Hunt and Hess grades and modified Fisher scores, treatment modality and outcomes as well as development of vasospasm, hydrocephalus and required treatment. Results Eighty-eight patients with pericallosal aneurysms were identified. Sixty-two presented with SAH and 26 in elective fashion, 2 of whom had a prior history of SAH. Fifty-four patients underwent microsurgical repair and 32 endovascular repair. Patients presenting with SAH due to pericallosal aneurysm treated with an endovascular approach were more likely to have a good modified Rankin scale (mRS) (mRS 0–2 vs 3–6) (p=0.028), to make a complete recovery (mRS=0) (p=0.017) and were less likely to die (mRS=6) (p=0.026). Patients with electively treated pericallosal aneurysms did not have statistically significant differences in outcome between surgical and endovascular cohorts. Differences in secondary endpoints did not reach significance. Conclusion Patients with ruptured pericallosal aneurysms fare better with endovascular therapy, with better chance of complete recovery. Surgical and endovascular treatments of unruptured pericallosal aneurysms have similar results and outcome.

Surgical Management of Intracranial Aneurysms in the Endovascular Era : Review Article

The advent of endovascular therapy for intracranial aneurysms and the rapid advances in that field have supplanted microsurgical treatment for many intracranial aneurysms. Applying current outcome data and other parameters, nuances of selecting the modality of treatment for intracranial aneurysms are reviewed. Patient factors, such a age, co-morbidities, vasospasm and other medical conditions, are addressed. A custom-tailored multimodality treatment paradigm for the management of ruptured and unruptured aneurysms will maximize the favorable results seen in this difficult patient population.

Antithrombotic states and outcomes in patients with angiographically negative subarachnoid hemorrhage.

BACKGROUND:Antithrombotic states are encountered frequently, either because of medical therapy or by preexistent pathological states, and may affect the severity of hemorrhagic strokes such as angiographically negative subarachnoid hemorrhages. OBJECTIVE:To determine the effects of antithrombotic states on the outcomes of patients with angiographically negative subarachnoid hemorrhage by examining data pooled from 2 institutions. METHODS:This is a retrospective review of patients who experienced angiographically negative subarachnoid hemorrhage at 2 institutions over the past 5 years. The patients were grouped into those with and those without an antithrombotic state at time of hemorrhage and were stratified according to presentation, clinical grades, outcomes, need for cerebrospinal fluid diversion, and development of vasospasm. Computed tomography of the head was assessed for bleed pattern and modified Fisher grade. Patients were excluded if a causative lesion was subsequently discovered. RESULTS:There is a statistically significant association between antithrombotic states and poorer presentation, higher Hunt and Hess score, increased amount of subarachnoid hemorrhage, higher modified Fisher grade, increased incidence of vasospasm, hydrocephalus, and poor outcomes as assessed by modified Rankin scale (P < .001). Patients with an antithrombotic state experience worse outcomes even with adjustment for the amount of hemorrhage as assessed by modified Fisher grade (P < .001). CONCLUSION:Patients in an antithrombotic state presenting with angiographically negative subarachnoid hemorrhage present with inferior clinical scores, diffuse hemorrhage patterns, and worse modified Fisher grades and have worse outcomes.

Early Aggressive Medical Management for Patients with Symptomatic Intracranial Stenosis

BACKGROUND There are limited data on the effect of an early aggressive risk factor modification program to achieve risk factor targets and its impact on clinical outcomes among patients with symptomatic intracranial stenosis. METHODS We prospectively identified patients with symptomatic intracranial stenosis of 50% to 99% (using computed tomographic angiography or cerebral angiography) who failed to qualify for or declined to participate in the Stenting and Aggressive Medical Management for Preventing Recurrent stroke in Intracranial Stenosis trial but elected to receive aggressive medical management. Aggressive medical management was defined as aspirin plus clopidogrel therapy for a minimum of 3 months, blood pressure control, statin use with a low-density lipoprotein (LDL) goal of <70 mg/dL, smoking cessation, and body mass index <25 kg/m(2). RESULTS Of 22 patients, the mean age was 65.6 ± 7.7 years, 82% were male, 59% were white, and mean percent stenosis was 71.5 ± 9.5% (55% with 70% to 99% stenosis). Median time from symptomatic event to first evaluation was 3 days. All patients completed 3 months of dual antiplatelet therapy, and at last follow-up, 86% had met their blood pressure goal, all were on statin therapy although only 73% had met their LDL goal, 96% reported no active tobacco use, and 36% had lost weight, but only 23% had achieved the BMI target. Over a mean follow-up of 1.2 years, there was no ischemic stroke, brain hemorrhage, or death from other vascular causes. CONCLUSIONS An early aggressive risk factor modification program achieved high levels of blood pressure and cholesterol targets for patients with symptomatic intracranial stenosis and when combined with dual antiplatelet therapy was effective for the prevention of recurrent vascular events in this cohort.

Flexible tip guides and intermediate catheters: two center experience and a proposed taxonomy

Background Stable access to target lesions is foundational to endovascular therapy, be it in hemorrhagic or ischemic disease. Continued evolution in access technology has resulted in next generation catheters that afford improved trackability and proximal support. Objective Assess safety and patterns of use at two high volume centers, and conceptualize usage patterns. Materials and methods A retrospective review of 608 cases in which a ‘next generation’ catheter was used during 2008–2010 at Cleveland Clinic (Cleveland, Ohio, USA) and throughout 2009–2010 at Emory University Hospital (Atlanta, Georgia, USA) was conducted, and the cases classified by indication. Catheter placement, distal most location, and related complications were recorded and experience summarized. We also reviewed the differences in the catheters and the rationale for catheter selection, as well as relative costs for each approach. Results 311 Neuron 053, 166 Neuron 070, 36 distal access catheter (DAC) 3.9 F, 61 DAC 4.3 F, and 34 DAC 5.2 F catheters were deployed. Of these, 459 placements were in the anterior circulation, 130 in the posterior circulation, 11 in the external carotid artery, and eight were used intravenously. Complication rates were 9/131 (6.9%) for the DAC catheter group, 16/311 (5.1%) for the Neuron 053 group, and 14/166 (8.4%) for the Neuron 070 group (p=0.37, χ2 test). Conclusions Next generation access catheters possess characteristics that blend qualities of traditional microcatheters and stiff guide catheters. There was no statistically significant difference in complication rates between the various catheter families in this small retrospective review, and the complication rates were similar to historical complication rates.