Extracranial/Intracranial Vascular Bypass in the Treatment of Head and Neck Cancer - Related Carotid Blowout Syndrome.

OBJECTIVE/HYPOTHESIS: To investigate the endovascular intervention or extracranial/intracranial (EC/IC) vascular bypass in the management of patients with head and neck cancer-related carotid blowout syndrome (CBS). STUDY DESIGN: Retrospective case series. METHODS: Retrospective analysis of clinical data of patients with head and neck cancer-related CBS treated by endovascular intervention and/or EC/IC vascular bypass, analysis of its bleeding control, neurological complications, and survival results. RESULTS: Thrity-seven patients were included. Twenty-five were associated with external carotid artery (ECA); twelve were associated with internal or common carotid artery (ICA/CCA). All patients with ECA hemorrhage were treated with endovascular embolization. Of the 12 patients with ICA/CCA hemorrhage, 9 underwent EC/IC bypass, 1 underwent endovascular embolization, and 3 underwent endovascular stenting. For patients with ECA-related CBS, the median survival was 6 months, and the 90-day, 1-year, and 2-year survival rates were 67.1%, 44.7%, and 33.6%, respectively; the estimated rebleeding risk at 1-month, 6-month, and 2-year was 7.1%, 20.0%, and 31.6%, respectively. For patients with ICA/CCA-related CBS, the median survival was 22.5 months, and the 90-day, 1-year, and 2-year survival rates were 92.3%, 71.8%, and 41.0%, respectively; the estimated rebleeding risk at 1 month, 6 months, and 2 years is 7.7%,15.4%, and 15.4%, respectively. ICA/CCA-related CBS patients have significantly longer survival time and lower risk of rebleeding, which may be related to the more use of EC/IC vascular bypass as a definite treatment. CONCLUSIONS: For patients with ICA/CCA-related CBS, if there is more stable hemodynamics, longer expected survival, EC/IC vascular bypass is preferred. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:1548-1556, 2021.

Impact of the COVID-19 outbreak on acute stroke pathways - insights from the Alsace region in France.

BACKGROUND AND PURPOSE: To date, no study has attempted to quantify the impact of the COVID-19 outbreak on the incidence and treatment of acute stroke. METHODS: This was a retrospective review of acute stroke pathway parameters in all three stroke units in the Alsace region during the first month of the outbreak (1-31 March 2020), using the similar period from 2019 as a comparator. A secondary detailed analysis of all stroke alerts and stroke unit admissions was performed in the centre with the largest case volume. RESULTS: Compared to the same period in 2019, in March 2020 there were 39.6% fewer stroke alerts and 33.3% fewer acute revascularization treatments [40.9% less intravenous thrombolysis (IVT) and 27.6% less mechanical thrombectomy (MT)]. No marked variation was observed in the number of stroke unit admissions (-0.6%). The proportion of patients with acute revascularization treatments (IVT or MT) out of the total number of stroke unit admissions was significantly lower in March 2020 (21.3%) compared to 2019 (31.8%), P = 0.034. There were no significant differences in time delays or severity of clinical symptoms for patients treated by IVT or MT, nor in the distribution of final diagnosis amongst stroke alerts and stroke unit admissions. CONCLUSION: These results suggest that the overall incidence of stroke remained the same, but fewer patients presented within the therapeutic time window. Increased public awareness and corrective measures are needed to mitigate the deleterious effects of the COVID-19 outbreak on acute stroke care.

Impact of EMS bypass to endovascular capable hospitals: geospatial modeling analysis of the US STRATIS registry.

BACKGROUND: Routing patients directly to endovascular capable centers (ECCs) would decrease time to mechanical thrombectomy (MT), but may delay intravenous thrombolysis (IVT). OBJECTIVE: To study the clinical outcomes of patients with a stroke transferred directly to ECCs compared with those transferred to ECCs from non-endovascular capable centers (nECCs). METHODS: Data from the STRATIS registry were analyzed to evaluate process and clinical outcomes under five routing policies: (1) transport to nearest nECC; (2) transport to STRATIS ECC over any distance or (3) within 20 miles; (4) transport to ideal ECC (iECC), over any distance or (5) within 20 miles. RESULTS: Among 236 patients, 117 (49.6%) were transferred by ground, of whom 62 (53%) were transferred within 20 miles. Median MT start time was accelerated in all direct transport models. IVT start was prolonged with direct transport across all distances, but accelerated with direct transport to iECC ≤20 miles. With bypass limited to ≤20 miles, the median modeled EMS arrival to IVT interval decreased for both iECCs and ECCs (by 12 min and 6 min, respectively), and median EMS arrival to puncture time decreased by up to 94 min. In this cohort, no patient would have become ineligible for IVT. Bypass to iECC modeling under 20 miles showed a significant reduction in the level of disability at 3 months, with freedom from disability (modified Rankin Scale score 0-1) at 3 months increased by 12%. CONCLUSIONS: Direct routing of patients with a large vessel occlusion to ECCs, especially when within 20 miles, may lead to better clinical outcomes by accelerating the start of MT without any delay of IVT. CLINICAL TRIAL REGISTRATION NUMBER: http://www.clinicaltrials.gov. Unique identifier: NCT02239640.

Trends in hospital procedure volumes for intra-arterial treatment of acute ischemic stroke: results from the paul coverdell national acute stroke program.

BACKGROUND: Rates of intra-arterial revascularization treatments (IAT) for acute ischemic stroke (AIS) are increasing in the USA. Using a multi-state stroke registry, we studied the trend in IAT use among patients with AIS over a period spanning 11 years. We examined the impact of IAT rates on hospital procedure volumes and patient outcome after stroke. METHODS: We used data from the Paul Coverdell National Acute Stroke Program (PCNASP) and explored trends in IAT between 2008 and 2018. Patient outcomes were examined by rates of IAT procedures across hospitals. Specifically, outcomes were compared across low-volume (<15 IAT per year), medium-volume (15-30 IAT per year), and high-volume hospitals (>30 IAT per year). Favorable outcome was defined as discharge to home. RESULTS: There were 612 958 patients admitted with AIS to 687 participating hospitals within the PCNASP during this study. Only 2.9% of patients (mean age 68.5 years, 49.3% women) received IAT. The percent of patients with AIS receiving IAT increased from 1% in 2008 to 5.3% in 2018 (p<0.001). The proportion of low-volume hospitals decreased over time (p<0.001), and the proportions of medium-volume (p=0.007) and high-volume hospitals (p<0.001) increased between 2008 and 2018. When compared with medium-volume hospitals, high-volume hospitals had a higher (p<0.0001) and low-volume hospitals had a lower (p<0.0001) percent of patients discharged to home. CONCLUSION: High-volume hospitals were associated with a higher rate of favorable outcome. With the increased use of IAT among patients with AIS, the proportion of low-volume hospitals performing IAT significantly decreased.

Symptomatic carotid near-occlusion causes a high risk of recurrent ipsilateral ischemic stroke.

OBJECTIVE: To assess the risk of recurrent ipsilateral ischemic stroke in patients with symptomatic near-occlusion with and without full collapse. METHODS: Included were consecutive patients eligible for revascularization, grouped into symptomatic conventional ≥ 50% carotid stenosis (n = 266), near-occlusion without full collapse (n = 57) and near-occlusion with full collapse (n = 42). The risk of preoperative recurrent ipsilateral ischemic stroke was analyzed, or, for cases not revascularized within 90 days, 90-day risk was analyzed. RESULTS: The risk of a preoperative recurrent ipsilateral ischemic stroke or ipsilateral retinal artery occlusion was 15% (95% CI 9-20%) for conventional ≥ 50% stenosis, 22% (95% CI 6-38%) among near-occlusion without full collapse and 30% (95% CI 16-44%) among near-occlusion with full collapse (p = 0.01, log rank test). In multivariate analysis, near-occlusion with full collapse had a higher risk of recurrent ipsilateral ischemic stroke (adjusted HR 2.6, 95% CI 1.3-5.3) and near-occlusion without full collapse tended to have a higher risk (adjusted HR 2.0, 95% CI 0.9-4.5) than conventional ≥ 50% stenosis. Only 24% of near-occlusion with full collapse underwent revascularization, common causes for abstaining were misdiagnosis as occlusion (31%), deemed surgically unfeasible (21%) and low perceived benefit (10%). CONCLUSIONS: Symptomatic carotid near-occlusion has a high short-term risk of recurrent ipsilateral ischemic stroke, especially near-occlusion with full collapse.

Impact of Statewide Telestroke Network on Acute Stroke Treatment in Hawai'i.

Hawai'i faces unique challenges in providing access to subspecialty care, particularly on the islands outside of O'ahu. Telemedicine allows remote treatment of patients with acute ischemic stroke by a neurologist with stroke expertise. The Hawai'i Telestroke Program was implemented in 2012 to connect hospitals with limited neurology coverage to a tertiary stroke center on O'ahu with 24/7 stroke neurology coverage. By 2017, seven hospitals were included in the program. The clinical data and revascularization therapy rate for all telestroke cases between January 2012 and July 2017 were analyzed. Annual telestroke consultations increased from 11 in 2012 to 203 in 2016. Among a total of 490 telestroke consultations, 318 patients (64.9%) were diagnosed with ischemic stroke while the remaining 172 patients had other diagnoses. Revascularization therapies, including intravenous tissue plasminogen activator and mechanical thrombectomy, were provided in 190 patients (38.8%). Using the discharge modified Rankin Scale, 141 (44.3%) patients were functionally independent at the time of hospital discharge, while 162 (50.9%) were disabled or dependent, and 15 (4.7%) died while in the hospital. Of the 490 telestroke consultations, 151 patients (30.8%) were transferred to the hub hospital while 69.2% of patients were able to remain in their local hospital. In summary, development of the Hawai'i Telestroke Program resulted in an increasing number of acute telestroke consultations and revascularization therapies at seven hospitals with limited neurological subspecialty coverage. Utilization of telemedicine in acute stroke treatment is feasible and may help address existing disparities of subspecialty care in Hawai'i.

Factors impacting on technical success in stroke thrombectomy: experience of a UK neuro-interventional unit.

AIM: To investigate factors that could impact on recanalisation and reperfusion in patients undergoing mechanical thrombectomy and to assess the technical success over time. MATERIALS AND METHODS: Two hundred consecutive patients who underwent thrombectomy for a proximal anterior circulation occlusion were dichotomised into equal groups (groups 1 and 2) based on the date that immediate access to emergency general anaesthesia (GA) commenced. RESULTS: Recanalisation success using thrombolysis in cerebral infarction (TICI) 2b/3 or TICI 2c/3 significantly improved in group 2 (67% versus 93%, p<0.0001; 52% versus 78%, p=0.0002). Symptomatic haemorrhage also reduced from 9% to 4%. Despite similar presentation Alberta Stroke Program Early (computed tomography) CT Scores (ASPECTS), post-procedural ASPECTS was significantly increased in group 2 (7; [interquartile range {IQR} 4-9] versus 8 [IQR 7-9]; p=0.0034). The number of patients with a post procedural ASPECTS of 8-10 increased (46% versus 64%, p=0.0155) and the difference in ASPECTS between pre- and post-thrombectomy CT was significantly lower (2 [IQR 1-4] versus 1 [IQR 0-2], p<0.0001). GA use increased from 8% to 56% (p=0.0001) as did use of distal aspiration (59% versus 87%, p=0.0001) mostly in combination with a stent-retriever. Failed access fell from 8% to 3%. When GA was used, successful recanalisation (TICI 2b/3) was achieved more frequently (90.5% versus 76.7%; OR 3.04, 1.2-7.69, p=0.0187). CONCLUSION: Technical results for thrombectomy are improving over time. Technique modification, operator experience, and judicious use of GA may be contributing.

Superficial Temporal Artery-Middle Cerebral Artery Bypass Surgery for Refractory Symptomatic Intracranial Atherosclerotic Stenosis.

OBJECTIVE: To evaluate blood flow changes after bypass surgery for refractory symptomatic intracranial atherosclerotic stenosis (ICAS). METHODS: We examined a cohort of consecutive patients with symptomatic ICAS. Superficial temporal artery-middle cerebral artery (MCA) bypass was performed in refractory patients with poor perfusion. Angiograms were graded systematically for antegrade, collateral, and bypass flow, and clinical variables were collected preoperatively, at 7 days postoperatively, and 3, 6, and 12 months postoperatively. RESULTS: Among 185 consecutive cases with ICAS, 15 patients who were unsuitable for or did not respond to the best medical therapy or stenting underwent bypass surgery. No patients had new ischemic deficits within 7 days postoperatively. The mean follow-up period was 30.2 ± 12.3 months. Within this period, all anastomoses were patent by methods of ultrasound or computed tomography angiography. In 2 patients, stenotic lesions exhibited early postoperative occlusion conversion at 7 days on digital subtraction angiography. In 2 patients, stenotic lesions showed progression of occlusion at 6 and 8 months. The 2 lesions with early occlusion were both located in the MCA. The extent of retrograde blood flow via bypass anastomosis was correlated with early occlusion conversion. CONCLUSIONS: For refractory ICAS in patients with compromised hemodynamics, direct bypass might induce early occlusion of a stenotic area. MCA lesions may have a greater tendency toward early occlusion conversion.

Flow Diverter Stents for the Treatment of Anterior Cerebral Artery Aneurysms: Safety and Effectiveness.

BACKGROUND AND PURPOSE: Flow diverter stents (FDSs) are increasingly used for the treatment of intracranial aneurysms. Initially developed for the management of giant and large aneurysms, their indications have progressively expanded. The purpose of our study was to evaluate the safety and effectiveness of FDSs for the treatment of anterior cerebral artery (ACA) aneurysms. MATERIALS AND METHODS: Among the 94 consecutive patients treated for 100 intracranial aneurysms by means of FDSs in our institution from October 2010 to January 2015, eight aneurysms (8 %) in seven patients were located on the ACA. Three aneurysms were located on the A1 segment, three aneurysms on the anterior communicating artery (ACom) and two on the A2-A3 junction. In three cases, FDS was used for angiographic recurrence after coiling. Five patients were treated with a Pipeline embolization device, one with a NeuroEndograft and the last one with a Silk FDS. RESULTS: Treatment was feasible in all cases. No technical difficulty was reported. No acute or delayed clinical complication was recorded. Modified Rankin Scale was 0 for six patients and one for one patient. Mean angiographic follow-up was 9.7 ± 3.9 months (range 6-15). Total exclusion was observed in five aneurysms (71.4 %) and neck remnant in two (28.6 %) cases. One patient refused the control DSA. CONCLUSION: Our series shows the safety and effectiveness of FDSs for the treatment of ACA aneurysms.

Safety and Efficacy of Surgical and Endovascular Treatment for Distal Anterior Cerebral Artery Aneurysms: A Systematic Review and Meta-Analysis.

BACKGROUND: Aneurysms of the distal anterior cerebral artery (DACA) are rare, representing between 1% and 9% of all intracranial aneurysms. The best treatment strategy for these aneurysms continues to be debated. OBJECTIVE: We conducted a systematic review of the literature to evaluate the safety and efficacy of treatment strategies of DACA aneurysms. METHODS: A systematic search of Medline, Embase, Scopus, and Web of Science was performed for studies published from January 2000 to August 2015. We included studies describing treatment of DACA aneurysms with ≥10 patients. Random effects meta-analysis was used to pool the following outcomes: complete occlusion, technical success, periprocedural morbidity/mortality and stroke rates, aneurysm recurrence/rebleed, and long-term neurologic morbidity/mortality. RESULTS: Thirty studies with 1329 DACA aneurysms were included. Complete occlusion was 95% (95% confidence interval [CI], 91.0%-97.0%) in the surgical group and 68% (95% CI, 56.0%-78.0%) in the endovascular group (P < 0.0001). Aneurysm recurrence occurred in 3% (95% CI, 2.0%-4.0%) after surgery and in 19.1% (95% CI, 12.0%-27.0%) after endovascular treatment (P < 0.0001). Overall neurologic morbidity and mortality were 15% (95% CI, 11.0%-21.0%) and 9% (95% CI, 7.0%-11.0%) after surgery and 14% (95% CI, 10.0%-19.0%) (P = 0.725) and 7% (95% CI, 5.0%-10.0%) (P = 0.422) after endovascular treatment, respectively. Overall long-term favorable neurologic outcome was 80% and it was equal in both groups (80%; 95% CI, 73.0%-85.0% in the surgical group and 80%; 95% CI, 72.0%-87.0% in the endovascular group) (P = 0.892). CONCLUSIONS: Our meta-analysis showed that both treatment modalities are technically feasible and effective with sufficient long-term aneurysm occlusion and acceptable recurrence/rebleed rates. Surgical treatment is associated with superior angiographic outcomes. There were no substantial differences in procedure-related morbidity and mortality. These findings are important because they suggest that therapy of DACA aneurysms should be performed on a selective, case-by-case basis to maximize patient benefits.

The anterior temporal artery: an underutilized but robust donor for revascularization of the distal middle cerebral artery.

OBJECTIVE The anterior temporal artery (ATA) supplies an area of the brain that, if sacrificed, does not cause a noticeable loss of function. Therefore, the ATA may be used as a donor in intracranial-intracranial (IC-IC) bypass procedures. The capacities of the ATA as a donor have not been studied previously. In this study, the authors assessed the feasibility of using the ATA as a donor for revascularization of different segments of the distal middle cerebral artery (MCA). METHODS The ATA was studied in 15 cadaveric specimens (8 heads, excluding 1 side). First, the cisternal segment of the artery was untethered from arachnoid adhesions and small branches feeding the anterior temporal lobe and insular cortex, to evaluate its capacity for a side-to-side bypass to insular, opercular, and cortical segments of the MCA. Any branch entering the anterior perforated substance was preserved. Then, the ATA was cut at the opercular-cortical junction and the capacity for an end-to-side bypass was assessed. RESULTS From a total of 17 ATAs, 4 (23.5%) arose as an early MCA branch. The anterior insular zone and the frontal parasylvian cortical arteries were the best targets (in terms of mobility and caliber match) for a side-to-side bypass. Most of the insula was accessible for end-to-side bypass, but anterior zones of the insula were more accessible than posterior zones. End-to-side bypass was feasible for most recipient cortical arteries along the opercula, except for posterior temporal and parietal regions. Early ATAs reached significantly farther on the insular MCA recipients than non-early ATAs for both side-to-side and end-to-side bypasses. CONCLUSIONS The ATA is a robust arterial donor for IC-IC bypass procedures, including side-to-side and end-to-side techniques. The evidence provided in this work supports the use of the ATA as a donor for distal MCA revascularization in well-selected patients.

Direct Bypass Versus Indirect Bypass in Adult Moyamoya Angiopathy with Symptoms or Hemodynamic Instability: A Meta-analysis of Comparative Studies.

BACKGROUND: It remains controversial which bypass methods are optimal for treating adult moyamoya angiopathy patients. This study aimed to analyze the literature about whether different bypass methods affect differently outcome results of adult moyamoya patients with symptoms or hemodynamic instability. METHODS: A systematic search of the PubMed, Embase, and Cochrane Central databases was performed for articles published between 1990 and 2015. Comparative studies about the effect of direct or combined bypass (direct bypass group) and indirect bypass (indirect bypass group) in patients with moyamoya angiopathy at 18 years of age or older were selected. For stroke incidence at the end of the follow-up period, the degree of angiographic revascularization, hemodynamic improvement, and perioperative complication rates within 30 days, pooled relative risks were calculated between the 2 groups with a 95% confidence interval. RESULTS: A total of 8 articles (including 536 patients and 732 treated hemispheres) were included in the meta-analysis. There were no significant differences between the 2 groups when we compared the overall stroke rate, the hemodynamic improvement rate, or the perioperative complication rate at the end of the follow-up period. The direct bypass group, however, had a lower risk than the indirect bypass group for obtaining a poor angiographic revascularization rate (risk ratio, 0.35; 95% confidence interval, 0.15-0.84; P = 0.02). CONCLUSIONS: The current meta-analysis suggests that the direct or combined bypass surgical method is better for angiographic revascularization in adult moyamoya patients with symptoms or hemodynamic instability. Future studies may be necessary to confirm these findings.

Is Carotid Revascularization Safe for Patients with Concomitant Carotid Stenosis and Intracranial Aneurysms?

OBJECTIVE: The safety of carotid revascularization in patients with concomitant extracranial carotid stenosis and cerebral aneurysm is rarely reported. We examine the risk of subarachnoid hemorrhage, aneurysm growth, ipsilateral transient ischemic attack, or stroke after revascularization in patients with both carotid stenosis and cerebral aneurysms. METHODS: A retrospective cohort study of patients with concomitant diagnosis of aneurysm and carotid stenosis evaluated in the neurosurgical department at our institution from 1990 to 2013 was carried out. Patients with both revascularized and nonrevascularized carotid stenosis were included. Demographic and angiographic characteristics, medical history, and treatment outcomes were collected. Comparison was made between the following 2 groups: revascularized carotid stenosis with stent or carotid endarterectomy versus nonrevascularized carotid stenosis. RESULTS: The study cohort consisted of 39 patients with 48 stenotic cervical internal carotid arteries and 51 cerebral aneurysms. Twenty patients (51.3%) underwent carotid endarterectomy/stenting, and 19 (48.7%) were managed medically. Patient characteristics were similar across the 2 groups except for increased severity of carotid stenosis (P < 0.001) and more posterior circulation aneurysms (P = 0.045) in the revascularized group. Ipsilateral stenosis and aneurysm was observed in 9 cases (40.9%) in the revascularized group and in 11 cases (42.3%) in the nonrevascularized group. During average follow-up of 1.62 years, no aneurysm rupture was observed. One ipsilateral stroke occurred in the revascularized group during follow-up, corresponding to an annual risk of 2.0%. One aneurysm enlargement occurred per group, with both located in the posterior circulation. CONCLUSIONS: Our study suggests that revascularization procedures for carotid stenosis should be considered safe and effective in patients with concomitant extracranial carotid occlusive disease and cerebral aneurysms.

National Analysis of 2454 Pediatric Moyamoya Admissions and the Effect of Hospital Volume on Outcomes.

BACKGROUND AND PURPOSE: Comprehensive multicenter data on treatment of pediatric moyamoya in the United States is lacking. We sought to identify national trends in the diagnosis and treatment of this disease. METHODS: A total of 2454 moyamoya admissions from 1997 to 2012 were identified from the Kids Inpatient Database. Demographics, inpatient costs, interventions, and discharge status were analyzed. Admissions with and without surgical revascularization were reviewed separately. The effect of hospital moyamoya volume on outcomes was analyzed by multivariate regression analysis. RESULTS: Care of moyamoya patients has been concentrating at high-volume centers during the past 12 years. Among moyamoya admission without surgical revascularization, high-volume hospitals show no difference in length of stay, cost, or complications compared with low-volume centers. However, low-volume hospitals have more nonroutine discharges (odds ratio, 2.32; P=0.0005) and inpatient deaths (odds ratio, 12.7; P=0.02) when no revascularization was performed. In contrast, among admissions with surgical revascularization, high-volume centers had decreased length of stay (4.7 versus 6.2 days; P=0.004), reduced cost ($88 000 versus $138 000; P<0.0001), and no increase in complications (P=0.29) compared with low-volume centers. Admissions with revascularization to low-volume hospitals also had increased likelihood of nonroutine discharge (odds ratio, 8.23; P=0.02) compared with high-volume centers. CONCLUSIONS: This is the largest study of US pediatric moyamoya admissions to date. These data demonstrate that volume correlates with outcome, indicating high-volume centers provide significantly improved care and reduced mortality in pediatric moyamoya patients, with the most marked benefit observed in admissions for surgical revascularization.

Temporal Trends in the Use of Investigations After Stroke or Transient Ischemic Attack.

BACKGROUND: Guidelines recommend that patients with stroke or transient ischemic attack (TIA) undergo neuroimaging and cardiac investigations to determine etiology and guide treatment. It is not known how the use of these investigations has changed over time and whether there have been associated changes in management. OBJECTIVES: To evaluate temporal trends in the use of brain and vascular imaging, echocardiography, and antithrombotic and surgical therapy after stroke or TIA. RESEARCH DESIGN: We analyzed 42,738 patients with stroke or TIA presenting to any of the 11 regional stroke centers in Ontario, Canada between 2003 and 2012 using the Ontario Stroke Registry database. The study period was divided into 1-year intervals and we used the Cochran-Armitage test to determine trends over time. RESULTS: Between 2003/2004 and 2011/2012, the proportion of patients undergoing brain imaging increased from 96% to 99%, as did the proportion receiving ≥3 brain scans (21%-39%), magnetic resonance imaging (13%-50%), vascular imaging (62%-88%), or echocardiography (52%-70%) (P<0.0001 for all comparisons). There was an increase in the proportion receiving any antithrombotic therapy (83%-91%, P<0.0001) but no change in use of anticoagulation (25% overall and 68% in subgroup with atrial fibrillation) or carotid revascularization (1.4%-1.5%, P=0.49). CONCLUSIONS: The use of investigations after stroke has increased over time without concomitant changes in medical or surgical management. Although initial neurovascular imaging is in accordance with practice guidelines, the use of multiple imaging procedures and routine echocardiography are of uncertain clinical effectiveness.

Flow-diverter devices in the treatment of intracranial aneurysms: A meta-analysis and systematic review.

OBJECTIVE: The purpose of this report was to discuss the overall limitations, safety and efficacy of flow-diverter stenting for intracranial aneurysms. METHODS: The authors performed a meta-analysis from January 2009 to September 2014 using the terms "flow diverter" and "intracranial aneurysms." Additional studies were identified through references in each reviewed article. Data extraction, performed independently by the authors, included demographic data, technical and clinical complications, morbidity and mortality, aneurismal occlusion rates related to flow-diverter devices. The analysis was performed using a fixed effect. RESULTS: Twenty-nine studies with 1524 patients and three to 62 months of follow-up were identified for analysis. The overall technical failure and complication rate was 9.3% (95% CI 6%-12.6%). The rate of procedure-related complication was 14% (95% CI 10.2%-17.9%) and 6.6% (95% CI 4%-9.1%) for morbidity and mortality. Fusiform, dissecting and circumferential aneurysm (OR 3.10, 95% CI 0.93-10.37) were significant risk factors for technical failure and complication. Posterior circulation location (OR 4.03, 95% CI 2.45-6.61), peripheral location (OR 2.74, 95% CI 1.52-4.94) and fusiform, dissecting and circumferential aneurysm (OR 1.95, 95% CI 1.15-3.30) were statistically significant risk factors for procedure-related complications. Posterior circulation location (OR 4.39, 95% CI 2.44-7.90) and peripheral location (OR 3.64, 95% CI 1.74-7.62) were statistically significant risk factors for morbidity and mortality. CONCLUSIONS: Fusiform, dissecting and circumferential aneurysm, posterior circulation and peripheral locations have greater procedure-related complications.

Direct Microsurgical Embolectomy for Acute Occlusion of the Internal Carotid Artery and Middle Cerebral Artery.

BACKGROUND: Surgical embolectomy is the most promising therapy for physically removing emboli from major cerebral arteries. However, it requires an experienced surgical team, time-consuming steps, and is not incorporated into acute stroke therapy. METHODS: We established seamless collaboration between services, refined surgical techniques, and conducted a prospective trial of emergency surgical embolectomy. Surgical indications included the presence of acute hemispheric symptoms, absence of low-density area on computed tomography, evidence of internal carotid artery terminus or proximal middle cerebral artery occlusion, and availability of resources to start surgery within 3 hours of symptom onset. The indications were confirmed by an interdisciplinary team. We assessed revascularization rates, time from admission to surgery and from surgery to recanalization, procedural complications, and clinical outcomes. RESULTS: Between 2005 and 2014, 14 consecutive patients with acute proximal middle cerebral artery or internal carotid artery terminus occlusion underwent emergency surgical embolectomy. All patients showed complete recanalization. Twelve patients survived and 7 had fair functional outcome (Rankin Scale score, ≤3). No significant procedural adverse events occurred. The mean times from admission to start of surgery, from surgery to recanalization, and from onset to recanalization were 14 minutes, 79 minutes, and 223 minutes, respectively. CONCLUSIONS: Our results suggest that microsurgical embolectomy can rapidly, safely, and effectively retrieve clots and deserves reappraisal, although the choice largely depends on local institutional expertise.

Relation between reperfusion and hemorrhagic transformation in acute ischemic stroke.

INTRODUCTION: Intravenous recombinant tissue plasminogen activator (IV-rtPA) is given in acute ischemic stroke patients to achieve reperfusion. Hemorrhagic transformation (HT) is a serious complication of IV-rtPA treatment and related to blood-brain barrier (BBB) injury. It is unclear whether HT occurs secondary to reperfusion in combination with ischemic BBB injury or is caused by the negative effect of IV-rtPA on BBB integrity. The aim of this study was to establish the association between reperfusion and the occurrence of HT. METHODS: From the DUST study, patients were selected with admission and follow-up non-contrast CT (NCCT) and CT perfusion (CTP) imaging, and a perfusion deficit in the middle cerebral artery territory on admission. Reperfusion was categorized qualitatively as reperfusion or no-reperfusion by visual comparison of admission and follow-up CTP. Occurrence of HT was assessed on follow-up NCCT. The association between reperfusion and occurrence of HT on follow-up was estimated by calculating odds ratios (ORs) and 95 % confidence intervals (CIs) with additional stratification for IV-rtPA treatment. RESULTS: Inclusion criteria were met in 299 patients. There was no significant association between reperfusion and HT (OR 1.2 95%CI 0.5-3.1). In patients treated with IV-rtPA (n = 203), the OR was 1.3 (95%CI 0.4-4.0), and in patients not treated with IV-rtPA (n = 96), the OR was 0.8 (95%CI 0.1-4.5). HT occurred in 14 % of the IV-rtPA patients and in 7 % of patients without IV-rtPA (95%CI of difference -1 to 14 %). CONCLUSION: Our results suggest that the increased risk of HT after acute ischemic stroke treatment is not dependent on the reperfusion status.

Surgeon case volume and 30-day mortality after carotid endarterectomy among contemporary medicare beneficiaries: before and after national coverage determination for carotid artery stenting.

BACKGROUND AND PURPOSE: After the 2005 National Coverage Determination to reimburse carotid artery stenting (CAS) for Medicare beneficiaries, the number of CAS procedures increased and carotid endarterectomy (CEA) decreased. We evaluated trends in surgeons' past-year CEA case-volume and 30-day mortality after CEA, and their association before and after the National Coverage Determination. METHODS: In a retrospective cohort study of patients undergoing CEA (2001-2008) and CAS (2005-2008) using Medicare data, we described yearly trends of CEA and CAS rates, patient characteristics, and 30-day mortality after CEA. We used logistic regression adjusting for patient- and surgeon-level factors to assess the effect of surgeon case volume on 30-day mortality after CEA. RESULTS: We identified 454 717 CEA and 27 943 CAS patients. Patients undergoing CEA in recent years were older and had more comorbidities than earlier years. CEA rates per 10 000 beneficiaries declined from 18.1 in 2002 to 12.7 in 2008, whereas median surgeon past-year case-volume declined from 27 to 21. The CAS rates peaked at 2.3 per 10 000 beneficiaries in 2006 but declined to 1.8 in 2008, resulting in declining overall revascularization procedure rates during 2005 to 2008. Thirty day post-CEA mortality was 1.40% (95% confidence interval, 1.34-1.47) in 2001 to 2002 and 1.17% (1.10-1.24) in 2007 to 2008. Surgeon's past-year case-volume of <10 was associated with higher 30-day mortality consistently during 2001 to 2008. CONCLUSIONS: The rate of CEA procedures decreased substantially during 2001 to 2008, as did surgeon past-year case-volume. The postprocedural mortality in Medicare beneficiaries was high compared with trial patients but somewhat improved over time. Those operated by lower past-year case-volume surgeons had increased mortality.

Carotid revascularization treatment is shifting to low volume centers.

BACKGROUND: Expansion of the endovascular and surgical workforce in the USA might lead to carotid revascularization procedures being carried out at low volume centers. OBJECTIVE: To evaluate trends in the treatment of carotid stenosis at high volume centers in the USA and compare outcomes by hospital volume. METHODS: Using the Nationwide Inpatient Sample, we evaluated trends in the proportion of carotid revascularization procedures performed at high volume centers in the USA from 2005 to 2011. High volume was defined as combined endarterectomy/stenting volume ≥ 130 patients/year, carotid endarterectomy volume ≥ 117 cases/year and carotid stenting volume ≥ 38 cases/year. In-hospital mortality, discharge to a long-term facility, intracranial hemorrhage, and postoperative stroke rates were compared between high and low volume centers. RESULTS: A total of 181,972 patients were included in this study. Overall, 63,442 patients (34.9%) were treated at high volume centers. The proportion of patients treated at high volume carotid revascularization centers decreased from 38.3% in 2005-2006 to 30.2% in 2010-2011. The proportion of patients treated at high volume centers decreased from 35.7% to 30.0% for carotid endarterectomy (p<0.0001) and 45.2% to 35.1% for carotid stenting. Patients treated at low volume centers had significantly higher rates of discharge to a long-term facility than high volume center patients (6.3% vs 5.0%, p<0.0001). The same was true for endarterectomy patients (6.0% vs 4.7%, p<0.0001) and stenting patients (8.3% vs 6.5%, p<0.0001). CONCLUSIONS: A trend toward a lower proportion of patients with carotid stenosis being treated in high volume centers from 2005 to 2011 is concerning as these high volume centers had lower complication rates.