Direct, Indirect, and Combined Extracranial-to-Intracranial Bypass for Adult Moyamoya Disease: An Updated Systematic Review and Meta-Analysis.

BACKGROUND: Moyamoya disease is a chronic, progressive cerebrovascular disease involving occlusion or stenosis of the terminal portion of the internal carotid artery. We conducted an updated systematic review and meta-analysis to investigate clinical and angiographic outcomes comparing direct, combined, and indirect bypass for the treatment of moyamoya disease in adults. METHODS: Two independent authors performed Preferred Reporting Items for Systematic reviews and Meta-Analyses guided literature searches in December 2021 to identify articles reporting clinical/angiographic outcomes in adult moyamoya disease patients undergoing bypass. Primary end points used were ischemic and hemorrhagic strokes, clinical outcomes, and angiographic revascularization. Study quality was evaluated with Newcastle-Ottawa and the Oxford Center for Evidence-Based Medicine scales. RESULTS: Four thousand four hundred fifty seven articles were identified in the initial search; 143 articles were analyzed. There were 3827 direct, 3826 indirect, and 3801 combined bypasses. Average length of follow-up was 3.59±2.93 years. Pooled analysis significantly favored direct (odds ratio [OR], 0.62 [0.48-0.79]; P<0.0001; OR, 0.44 [0.32-0.59]; P<0.0001; OR, 0.56 [0.42-0.74]; P<0.0001; OR, 3.1 [2.5-3.8]; P=0.0001) and combined (OR, 0.53 [0.41-0.69]; P<0.0001; OR, 0.28 [0.2-0.41]; P<0.0001; OR, 0.41 [0.3-0.56]; P<0.0001; OR, 3.1 [2.8-4.3]; P=0.0001) over indirect bypass for early stroke, late stroke, late intracerebral hemorrhage, and favorable outcomes, respectively. Indirect bypass was favored over combined (OR, 3.1 [1.7-5.6]; P<0.0001) and direct (OR, 4.12 [2.34-7.25]; P<0.0001) for early intracerebral hemorrhage. The meta-analysis significantly favored direct (OR, 0.37 [0.23-0.60]; P<0.001; OR, 0.49 [0.31-0.77]; P=0.002) and combined (OR, 0.23 [0.12-0.43]; P<0.00001; OR, 0.30 [0.18-0.49]; P<0.00001) bypass over indirect bypass for late stroke and late hemorrhage, respectively. Combined bypass was favored over indirect bypass for favorable outcomes (OR, 2.06 [1.18-3.58]; P=0.01). CONCLUSIONS: Based on combined meta-analysis (43 articles) and pooled analysis (143 articles), the existing literature indicates that combined and direct bypasses have significant benefits for patients suffering from late stroke and hemorrhage versus indirect bypass. Combined bypass was favored over indirect bypass for favorable outcomes. This is a strong recommendation based on low-quality evidence when utilizing the Grades of Recommendation, Assessment, Development, and Evaluation system. These findings have important implications for bypass strategy selection.

External validation of TICI-ASPECTS-glucose score as a predictive model for symptomatic intracranial hemorrhage following mechanical thrombectomy.

INTRODUCTION: The indication for mechanical thrombectomy for acute ischemic stroke (AIS) secondary to large vessel occlusion has substantially increased in the past few years, but predictors of symptomatic intracranial hemorrhage (sICH) remain largely unstudied. A recent study assessing these predictors, led to the development of the TICI-ASPECTS-glucose (TAG) score, an internally validated model to predict sICH following thrombectomy. METHODS: To externally validate this scoring system and identify other potential risk factors for hemorrhagic conversion following endovascular therapy for AIS, 420 consecutive patients treated with mechanical thrombectomy from 2014-2017 were retrospectively reviewed. Data were collected pertaining to admission factors, procedural metrics, and functional outcomes. The components comprising the TAG score consist of modified thrombolysis in cerebral infarction (mTICI) score (mTICI 0-2a=2 points; 2b-3=0 points), Alberta stroke program early CT (ASPECTS) score (<6=4 points, 6-7=2 points, ≥8=0 points), and glucose (≥150 mg/dL=1 point, <150 mg/dL=0 points). Statistical analyses including univariate analysis, logistic regression analysis, and area under the receiver-operating curve (AUROC) were performed to validate the predictive capability of the model. RESULTS: The patients with sICH presented with lower ASPECTS (8.13±1.55 v 9.16±1.24, p < 0.001), but no significant correlation with mTICI scores and admission glucose was observed. Decreasing ASPECTS correlated with increased risk of sICH (OR 1.57, 95% CI 1.25-1.96, p < 0.001), and increasing TAG score was associated with increased sICH (OR 1.46, 95% CI 1.11-1.94, p < 0.01). AUROC of the model was 0.633. Stratifying patients into low (TAG 0-2), intermediate,3,4 and high5-7 risk groups identified similar results to the original study with sICH risks of 5.2%, 10.5%, and 33.3%, respectively. CONCLUSION: The TICI-ASPECTS-glucose (TAG) score adequately predicts sICH following mechanical thrombectomy, and appropriately stratifies individual patient risk. Further inclusion of additional predictors of sICH would likely yield a more robust model.

Hemicraniectomy for Malignant Middle Cerebral Artery Syndrome: A Review of Functional Outcomes in Two High-Volume Stroke Centers.

BACKGROUND AND PURPOSE: Despite recent landmark randomized controlled trials showing significant benefits for hemicraniectomy (HCT) compared with medical therapy (MT) in patients with malignant middle cerebral artery infarction (MMCAI), HCT rates have not substantially increased in the United States. We sought to evaluate early outcomes in patients with MMCAI who were treated with HCT (cases) in comparison to patients treated with MT due to the perception of procedural futility by families (controls). METHODS: We retrospectively evaluated consecutive patients with acute MMCAI treated in 2 tertiary care centers during a 7-year period. Pretreatment National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS) at 3 months were documented. Functional independence (FI) and survival without severe disability (SWSD) were defined as mRS of 0-2 and 0-4, respectively. RESULTS: A total of 66 patients (37 cases and 29 controls) fulfilled the study inclusion criteria (mean age 59 ± 15 years, 52% men, median admission NIHSS score: 19 points [interquartile range {IQR}: 16-22]). Cases were younger (51 ± 11 versus 68 ± 13 years; P < .001) and tended to have lower median admission NIHSS than controls (18 [IQR:16-20] versus 20 [IQR:18-23]; P = .072). The rates of FI and SWSD at 3 months were higher in cases than controls (16% versus 0% [P = .031] and 62% versus 0% [P < .001]), while 3-month mortality was lower (24% versus 77%; P < .001). Multivariable Cox regression analyses adjusting for potential confounders identified HCT as the most important predictor of lower risk of 3-month mortality (hazard ratio: .02, 95% confidence interval: .01-0.10; P < .001). CONCLUSIONS: HCT is a critical and effective therapy for patients with MMCAI but cannot provide a guarantee of functional recovery.

Machine learning for clinical outcome prediction in cerebrovascular and endovascular neurosurgery: systematic review and meta-analysis.

BACKGROUND: Machine learning (ML) may be superior to traditional methods for clinical outcome prediction. We sought to systematically review the literature on ML for clinical outcome prediction in cerebrovascular and endovascular neurosurgery. METHODS: A comprehensive literature search was performed, and original studies of patients undergoing cerebrovascular surgeries or endovascular procedures that developed a supervised ML model to predict a postoperative outcome or complication were included. RESULTS: A total of 60 studies predicting 71 outcomes were included. Most cohorts were derived from single institutions (66.7%). The studies included stroke (32), subarachnoid hemorrhage ((SAH) 16), unruptured aneurysm (7), arteriovenous malformation (4), and cavernous malformation (1). Random forest was the best performing model in 12 studies (20%) followed by XGBoost (13.3%). Among 42 studies in which the ML model was compared with a standard statistical model, ML was superior in 33 (78.6%). Of 10 studies in which the ML model was compared with a non-ML clinical prediction model, ML was superior in nine (90%). External validation was performed in 10 studies (16.7%). In studies predicting functional outcome after mechanical thrombectomy the pooled area under the receiver operator characteristics curve (AUROC) of the test set performances was 0.84 (95% CI 0.79 to 0.88). For studies predicting outcomes after SAH, the pooled AUROCs for functional outcomes and delayed cerebral ischemia were 0.89 (95% CI 0.76 to 0.95) and 0.90 (95% CI 0.66 to 0.98), respectively. CONCLUSION: ML performs favorably for clinical outcome prediction in cerebrovascular and endovascular neurosurgery. However, multicenter studies with external validation are needed to ensure the generalizability of these findings.

Prevalence of unruptured intracranial aneurysms (UIAs) examined in the trauma population.

BACKGROUND: Previous data on the prevalence of unruptured intracranial aneurysms (UIAs) vary widely, and studies based on these data are plagued with unintentional bias. Accurate prevalence data are paramount for any physician who counsels patients with intracranial aneurysms on rupture risk and treatment. We therefore sought to determine a more accurate number for the true prevalence of UIAs. METHODS: A retrospective chart review was conducted at a level 1 trauma center and tertiary care hospital in an urban setting between 2019 and 2020. Inclusion criteria included patients admitted with blunt trauma. Exclusion criteria included not having a head and neck CTA performed and read by an attending radiologist. All head and neck CTA radiology reads were reviewed for incidentally discovered UIAs. Subgroup analysis was performed by age group, race, and gender. RESULTS: A total of 5978 out of 8999 patients met the inclusion criteria, and 54 patients with 58 total aneurysms were identified giving an overall prevalence of 0.9%. Subgroup analysis was performed for all age groups, genders, and racial groups. CONCLUSION: The overall aneurysm prevalence was found to be 0.9% in this sample. This rate is lower than rates previously cited in the literature and those quoted in local practice. This finding has significant implications when attempting to understand average rupture risk. Further studies are needed to power more subgroup analyses to use a more personalized approach to understanding an individual's risk of rupture.

Acute and Long-Term Management of Blunt Cerebrovascular Injury at a Quaternary Referral Level 1 Trauma Center: The Memphis Experience and Comparison of a New Scoring System.

BACKGROUND AND OBJECTIVES: The management of blunt cerebrovascular injuries (BCVIs) remains an important topic within trauma and neurosurgery today. There remains a lack of consensus within the literature and significant variation across institutions. The purpose of this study was to evaluate management of BCVI at a large, tertiary referral trauma center. METHODS: Institutional Review Board approval was obtained to conduct a retrospective review of patients with BCVI at our Level 1 Trauma Center. Computed tomography angiography was used to identify BCVI for each patient. Patient information was collected, and statistical analysis was performed. With the included risk factors for ischemic complications, a novel scoring system based on ischemic risk, the "Memphis Score," was developed and evaluated to grade BCVI. RESULTS: Two hundred seventeen patients with BCVI from July 2020 to August 2022 were identified. The most common mechanism of injury was motor vehicle collision (141, 65.0%). Vertebral arteries were the most common vessel injured (136, 51.1%) with most injuries occurring at a high cervical location (101, 38.0%). Denver Grade 1 injuries (89, 33.5%) and a Memphis Score of 1 were most frequent (172, 64.6%), and initial anticoagulation with heparin drip was initiated 56.7% of the time (123). Endovascular treatment was required in 24 patients (11.1%) and was usually performed in the first 48 hours (15, 62.5%). While Denver Grade (P = .019) and Memphis Score (P < .00001) were significantly higher in those patients undergoing endovascular treatment, only the Memphis Score demonstrated a significant difference between those patients who had stroke or worsening on follow-up imaging and those who did not (P = .0009). CONCLUSION: Although BCVI management has improved since early investigative efforts, institutions must evaluate and share their data to help clarify outcomes. The novel "Memphis Score" presents a standardized framework to communicate ischemic risk and guide management of BCVI.

Extracranial-Intracranial Cerebral Revascularization for Atherosclerotic Vessel Occlusion: An Updated Systematic Review of the Literature.

BACKGROUND: Atherosclerotic steno-occlusive cerebrovascular disease includes extracranial carotid occlusive and intracranial atherosclerotic disease. Despite the negative findings in Carotid Occlusion Surgery Study (COSS), many large centers continue to report favorable results for revascularization surgery in select groups of patients. The aim of our study was to perform an updated systematic review to investigate the role of revascularization surgery for atherosclerotic steno-occlusive patients in the modern era. METHODS: Five independent reviewers performed Preferred Reporting Items for Systematic Reviews and Meta-Analyses-guided literature searches in October 2022 to identify articles reporting clinical outcomes in adult patients undergoing bypass for atherosclerotic steno-occlusive disease. Primary endpoints used were perioperative and long-term ischemic strokes, intracerebral hemorrhage, bypass patency, and favorable clinical outcomes. Study quality was evaluated with Newcastle-Ottawa, JADAD, and the Oxford Center for Evidence-Based Medicine scales. RESULTS: A total of 6709 articles were identified in the initial search. Of these articles, 50 met the inclusion criteria and were included in the systematic review. A notable increase in the proportion of articles published over the past 10 years was observed. There were 6046 total patients with 4447 bypasses performed over the period from 1978 to 2022. The average length of follow-up was 2.75 ± 2.71 years. The average Newcastle-Ottawa was 6.23 out of 9 stars. There was a significant difference in perioperative stroke (odds ratio [OR], 0.65 [0.48-0.87]; P = 0.004), long-term ischemia (OR, 0.32 [0.23-0.44]; P < 0.0001), overall ischemia (OR, 0.36 [0.28-0.44]; P < 0.0001), and favorable outcomes (OR, 3.63 [2.84-4.64]; P < 0.0001) when comparing pre-COSS to post-COSS time frames in favor of post-COSS. CONCLUSIONS: Based on a systematic review of 50 articles, the existing literature indicates that long-term stroke rates and favorable outcomes for surgical revascularization for steno-occlusive disease have improved over time and are lower than previously reported. Improved patient selection, perioperative care, and surgical techniques may contribute to improved outcomes.

Flat-panel detector CT to assess intracranial hemorrhage immediately following mechanical thrombectomy.

BACKGROUND AND PURPOSE: The risk of symptomatic intracranial hemorrhage (ICH) approaches 5% despite mechanical thrombectomy (MT) efficacy for ischemic stroke secondary to large vessel occlusion. Flat-panel detector CT (FDCT) imaging with Syngo Dyna CT imaging (Siemens Medical Solutions, Malvern, PA) can be used immediately following MT to detect ICH. PURPOSE: To evaluate the accuracy and reliability of FDCT imaging with Dyna CT compared to conventional post-MT CT and MRI. METHODS: Head FDCT (20 second, 70 kV) was performed immediately following MT on 26 consecutive patients; postprocedural CT or MRI was obtained ∼24 hours later. Two blinded, independent neuroradiologists evaluated all imaging, identifying ICH, stroke, and presence of subarachnoid contrast. Cohen's κ statistic was used to assess interrater agreement for each imaging outcome and compared the FDCT to conventional imaging. RESULTS: FDCT for ICH demonstrated a strong degree of interrater reliability (κ = 0.896; 95% confidence interval [CI], 0.734-1.057). Negligible reliability was seen for ischemia determination on immediate post-MT FDCT (κ = 0.149; 95% CI, -0.243 to 0.541). ICH evaluation between FDCT and post-MT conventional CT revealed modest interrater reliability (κ = 0.432; 95% CI, -0.100 to 0.965), which did not reach statistical significance. There was no substantive reliability in the evaluation of ICH between FDCT and post-MT MRI (κ = 0.118, 95% CI, -0.345 to 0.580). CONCLUSION: FDCT, such as Dyna CT, immediately post-MT is a promising tool that can expedite the detection of ICH with a high degree of reliability, although the detection of ischemic parenchymal changes is limited.

Safety and effectiveness of the Woven EndoBridge (WEB) system for the treatment of wide necked bifurcation aneurysms: final 5 year results of the pivotal WEB Intra-saccular Therapy study (WEB-IT).

INTRODUCTION: The US Woven EndoBridge Intra-saccular Therapy (WEB-IT) study is a pivotal, prospective, single arm, investigational device exemption study to evaluate the safety and effectiveness of the WEB device for the treatment of wide neck bifurcation aneurysms (WNBAs). We present complete 5 year data for the cohort of 150 patients. METHODS: 150 patients with WNBAs were enrolled at 21 US and six international centers. Imaging from the index procedure, 6 month, 1 year, 3 year, and 5 year follow-up were reviewed by a core laboratory. Adverse events were reviewed and adjudicated by a clinical events adjudicator. RESULTS: 83 patients had 5 year follow-up imaging and 123 had clinical follow-up. No ruptured (0/9) or unruptured aneurysm (0/141) rebled or bled during follow-up. No new device or procedure related adverse events or serious adverse events were reported after 1 year. At 5 years, using the LOCF method, complete occlusion was observed in 58.1% and adequate occlusion in 87.2% of patients. For patients with both 1 year and 5 year occlusion statuses available, 76.8% (63/82) of aneurysms remained stable or improved with no retreatment. After 1 year, 18 aneurysms were retreated, 11 of which were adequately occluded at 1 year, and 15 of which were retreated in the absence of any deterioration in occlusion grade. CONCLUSIONS: Five year follow-up data from the WEB-IT study demonstrated that the WEB device was safe and effective when used in the treatment of WNBAs. Aneurysm occlusion rates achieved at 1 year follow-up were durable, with rates of progressive thrombosis far exceeding rates of recurrence over time.

Stroke imaging modality for endovascular therapy in the extended window: systematic review and meta-analysis.

BACKGROUND: In anterior circulation large vessel occlusion (LVO) in the extended time window, the guidelines recommend advanced imaging (ADVI) to select patients for endovascular therapy (EVT). However, questions remain regarding its availability and applicability in the real world. It is unclear whether an approach to the extended window EVT that does not use ADVI would be equivalent. METHODS: In April 2022, a literature search was performed to identified randomized controlled trials (RCT) and observational studies describing 90-day outcomes. We performed a meta-analysis of the proportion of aggregate using a random effect to estimate rates of functional independence, defined as modified Rankin Scale (mRS) score ≤2 at 90 days, mean mRS, mortality and symptomatic intracranial hemorrhage (sICH) stratified by imaging modality. RESULTS: Four RCTs and 28 observational studies were included. The pooled proportion of functional independence among patients selected by ADVI was 44% (95% CI 39% to 48%; I2=80%) and 48% (95% CI 41% to 55%; I2=75%) with non-contrast CT/CT angiography (NCCT/CTA) (p=0.36). Mean mRS with ADVI was 2.88 (95% CI 2.36 to 3.41; I2=0.0%) and 2.79 (95% CI 2.31 to 3.27; I2=0.0%) with NCCT (p=0.79). Mortality in patients selected by ADVI was 13% (95% CI 10% to 17%; I2=81%) and 16% (95% CI 12% to 22%; I2=69%) with NCCT (p=0.29). sICH with ADVI was 4% (95% CI 3% to 7%; I2=73%) and 6% with NCCT/CTA (95% CI 4% to 8%; I2=6%, p=0.27). CONCLUSIONS: Our study suggests that, in anterior circulation LVO, the rates of functional independence may be similar when patients are selected using ADVI or NCCT for EVT in the extended time window. A simplified triage protocol does not seem to increase mortality or sICH. PROTOCOL REGISTRATION NUMBER: (PROSPERO ID: CRD42021236092).

Long-Term Follow-up of Aneurysms Treated With Hydrogel-Coated Coils Shows Progressive Thrombosis and Improvement in Raymond-Roy Classification.

BACKGROUND: Coil embolization of aneurysms has been shown to be a safe and effective method of aneurysm treatment. Hydrogel-coated coils were developed as a hybrid embolization device to increase the packing density of a coil mass in an aneurysm and to reduce retreatment and rerupture rates. Previous studies have shown a benefit compared with bare metal coils. OBJECTIVE: To present long-term follow-up of a cohort of patients treated with hydrogel-coated coils to better determine the effectiveness compared with bare platinum coils. METHODS: Between January 2003 and April 2012, we identified patients with both ruptured and unruptured aneurysms coiled at our institution, using some portion of hydrogel-coated coils. Planned follow-up angiography was performed at 6 months, 18 months, and 5 years post-treatment. All imaging was independently adjudicated by a single physician at a separate institution. The results were scored with the modified Raymond-Roy Occlusion Classification. RESULTS: A total of 145 patients with 153 treated aneurysms were included in the study analysis. Immediately after treatment, 49% of aneurysms were classified at Raymond-Roy Occlusion Classification I or II, which improved to 83% by 6 months. This percent plateaued at 18-month and 5-year follow-up, measuring 86% and 90%, respectively. The retreatment rate was 14% over the 5-year period, and there were no rerupture events captured. CONCLUSION: Treatment of intracranial aneurysms with coil embolization using hydrogel-coated aneurysms shows evidence of progressive occlusion, particularly over the first 6 months of follow-up. The retreatment rate is comparable with historical data, and the rerupture rate is low.

Automated emergent large vessel occlusion detection by artificial intelligence improves stroke workflow in a hub and spoke stroke system of care.

BACKGROUND: Emergent large vessel occlusion (ELVO) acute ischemic stroke is a time-sensitive disease. OBJECTIVE: To describe our experience with artificial intelligence (AI) for automated ELVO detection and its impact on stroke workflow. METHODS: We conducted a retrospective chart review of code stroke cases in which VizAI was used for automated ELVO detection. Patients with ELVO identified by VizAI were compared with patients with ELVO identified by usual care. Details of treatment, CT angiography (CTA) interpretation by blinded neuroradiologists, and stroke workflow metrics were collected. Univariate statistical comparisons and linear regression analysis were performed to quantify time savings for stroke metrics. RESULTS: Six hundred and eighty consecutive code strokes were evaluated by AI; 104 patients were diagnosed with ELVO during the study period. Forty-five patients with ELVO were identified by AI and 59 by usual care. Sixty-nine mechanical thrombectomies were performed.Median time from CTA to team notification was shorter for AI ELVOs (7 vs 26 min; p<0.001). Door to arterial puncture was faster for transfer patients with ELVO detected by AI versus usual care transfer patients (141 vs 185 min; p=0.027). AI yielded a time savings of 22 min for team notification and a 23 min reduction in door to arterial puncture for transfer patients. CONCLUSIONS: AI automated alerts can be incorporated into a comprehensive stroke center hub and spoke system of care. The use of AI to detect ELVO improves clinically meaningful stroke workflow metrics, resulting in faster treatment times for mechanical thrombectomy.

Sequential Flow Diversion After Nitinol Stent Placement for a Large, Matricidal Cavernous Internal Carotid Artery Aneurysm: Technical Video.

The Surpass Evolve flow diverter is a novel 64-wire braided intravascular stent approved to treat unruptured large or giant saccular wide-neck or fusiform intracranial aneurysms of the intracranial internal carotid artery.1-3 Flow diverting stents have been used for the treatment of previously stented aneurysms, including residual aneurysms following prior flow diversion.5-8 This patient initially presented with a large symptomatic matricidal cavernous ICA aneurysm4 that was treated with stand-alone Neuroform Atlas stenting at an outside hospital. Here we present a video demonstrating the placement of sequential Surpass Evolve flow diverter stents within a Neuroform Atlas nitinol stent.

Double-Barrel (2-Donor-2-Recipient) Bypass as Rescue Treatment for Patient with Occluded Middle Cerebral Artery Intracranial Stent and Recurrent Ischemia.

Stent occlusion is a challenging complication following endovascular interventions that require intracranial stenting.1-4 Although there are small series describing revascularization for stenoocclusive disease failing best medical management,5-14 there are few reports in the literature regarding surgical bypass as a treatment for stent occlusion.5 We present the case of a 37-year-old man who presented with right-sided weakness, numbness, and difficulty with speech and ambulation. His history is notable for a left M1 (segment of middle cerebral artery) occlusion 6 months prior that was treated with mechanical thrombectomy requiring repeat thrombectomy and rescue acute middle cerebral artery (MCA) stent placement given vessel reocclusion. Diagnostic cerebral angiography demonstrated stent occlusion. Given his continued ischemic symptoms despite best medical management, the patient underwent a double-barrel superficial temporal artery-MCA direct bypass to revascularize the MCA territory. To our knowledge, there is no literature to date describing a 2-donor-2-recipient direct bypass for the rescue treatment of symptomatic intracranial stent occlusion with recurrent ischemia. We review the case presentation, angiographic findings, surgical nuances, and postoperative course with imaging. The patient provided informed consent for the procedure and verbal support for publishing his image and inclusion in this submission.

Woven EndoBridge Embolized Aneurysm Clippings: 2-Dimensional Operative Video.

The Woven EndoBridge (WEB) device (MicroVention, Aliso Viejo, California) is an intrasaccular flow disruptor used for the treatment of both unruptured and ruptured intracranial aneurysms. WEB has been shown to have 54% complete and 85% adequate aneurysm occlusion rates at 1-yr follow-up.1 Residual and recurrent ruptured aneurysms have been shown to have a higher risk of re-rupture than completely occluded aneurysms.2 With increased utilization of WEB in the United States, optimizing treatment strategies of residual aneurysms previously treated with the WEB device is essential, including surgical clipping.3,4 Here, we present an operative video demonstrating the surgical clip occlusion of previously ruptured middle cerebral artery and anterior communicating artery aneurysms that had been treated with the WEB device and had sizable recurrence on follow-up angiography. Informed consent was obtained from both patients. Lessons learned include the following: (1) the WEB device is highly compressible, unlike coils; (2) proximal WEB marker may interfere with clip closure; (3) no evidence of WEB extrusion into the subarachnoid space; (4) no more scarring than expected in ruptured cases; and (5) clipping is a feasible option for treating WEB recurrent or residual aneurysms.

Predicting the degree of difficulty of the trans-radial approach in cerebral angiography.

BACKGROUND: To evaluate anatomical and clinical factors that make trans-radial cerebral angiography more difficult. METHODS: A total of 52 trans-radial diagnostic angiograms were evaluated in a tertiary care stroke center from December 2019 until March 2020. We analyzed a number of anatomical variables to evaluate for correlation to outcome measures of angiography difficulty. RESULTS: The presence of a proximal radial loop had a higher conversion to femoral access (p<0.03). The presence of a large diameter aortic arch (p<0.01), double subclavian innominate curve (p<0.01), left proximal common carotid artery (CCA) loop (p<0.001), acute subclavian vertebral angle (p<0.01), and absence of bovine aortic arch anatomy (p=0.03) were associated with more difficult trans-radial cerebral angiography and increased fluoroscopy time-per-vessel. CONCLUSION: The presence of a proximal radial loop, large diameter aortic arch, double subclavian innominate curve, proximal left CCA loop, acute subclavian vertebral angle, and absence of bovine aortic arch anatomy were associated with more difficult trans-radial cerebral angiography. We also introduce a novel grading scale for diagnostic trans-radial angiography.

Direct to Angiography vs Repeated Imaging Approaches in Transferred Patients Undergoing Endovascular Thrombectomy.

Importance: A direct to angiography (DTA) treatment paradigm without repeated imaging for transferred patients with large vessel occlusion (LVO) may reduce time to endovascular thrombectomy (EVT). Whether DTA is safe and associated with better outcomes in the late (>6 hours) window is unknown. Also, DTA feasibility and effectiveness in reducing time to EVT during on-call vs regular-work hours and the association of interfacility transfer times with DTA outcomes have not been established. Objective: To evaluate the functional and safety outcomes of DTA vs repeated imaging in the different treatment windows and on-call hours vs regular hours. Design, Setting, and Participants: This pooled retrospective cohort study at 6 US and European comprehensive stroke centers enrolled adults (aged ≥18 years) with anterior circulation LVO (internal cerebral artery or middle cerebral artery subdivisions M1/M2) and transferred for EVT within 24 hours of the last-known-well time from January 1, 2014, to February 29, 2020. Exposures: Repeated imaging (computed tomography with or without computed tomographic angiography or computed tomography perfusion) before EVT vs DTA. Main Outcomes and Measures: Functional independence (90-day modified Rankin Scale score, 0-2) was the primary outcome. Symptomatic intracerebral hemorrhage, mortality, and time metrics were also compared between the DTA and repeated imaging groups. Results: A total of 1140 patients with LVO received EVT after transfer, including 327 (28.7%) in the DTA group and 813 (71.3%) in the repeated imaging group. The median age was 69 (interquartile range [IQR], 59-78) years; 529 were female (46.4%) and 609 (53.4%) were male. Patients undergoing DTA had greater use of intravenous alteplase (200 of 327 [61.2%] vs 412 of 808 [51.0%]; P = .002), but otherwise groups were similar. Median time from EVT center arrival to groin puncture was faster with DTA (34 [IQR, 20-62] vs 60 [IQR, 37-95] minutes; P < .001), overall and in both regular and on-call hours. Three-month functional independence was higher with DTA overall (164 of 312 [52.6%] vs 282 of 763 [37.0%]; adjusted odds ratio [aOR], 1.85 [95% CI, 1.33-2.57]; P < .001) and during regular (77 of 143 [53.8%] vs 118 of 292 [40.4%]; P = .008) and on-call (87 of 169 [51.5%] vs 164 of 471 [34.8%]; P < .001) hours. The results did not vary by time window (0-6 vs >6 to 24 hours; P = .88 for interaction). Three-month mortality was lower with DTA (53 of 312 [17.0%] vs 186 of 763 [24.4%]; P = .008). A 10-minute increase in EVT-center arrival to groin puncture in the repeated imaging group correlated with 5% reduction in the functional independence odds (aOR, 0.95 [95% CI, 0.91-0.99]; P = .01). The rates of modified Rankin Scale score of 0 to 2 decreased with interfacility transfer times of greater than 3 hours in the DTA group (96 of 161 [59.6%] vs 15 of 42 [35.7%]; P = .006), but not in the repeated imaging group (75 of 208 [36.1%] vs 71 of 192 [37.0%]; P = .85). Conclusions and Relevance: The DTA approach may be associated with faster treatment and better functional outcomes during all hours and treatment windows, and repeated imaging may be reasonable with prolonged transfer times. Optimal EVT workflow in transfers may be associated with faster, safe reperfusion with improved outcomes.

Aneurysm inflow-angle as a discriminant for rupture in sidewall cerebral aneurysms: morphometric and computational fluid dynamic analysis.

BACKGROUND AND PURPOSE: The ability to discriminate between ruptured and unruptured cerebral aneurysms on a morphological basis may be useful in clinical risk stratification. The objective was to evaluate the importance of inflow-angle (IA), the angle separating parent vessel and aneurysm dome main axes. METHODS: IA, maximal dimension, height-width ratio, and dome-neck aspect ratio were evaluated in sidewall-type aneurysms with respect to rupture status in a cohort of 116 aneurysms in 102 patients. Computational fluid dynamic analysis was performed in an idealized model with variational analysis of the effect of IA on intra-aneurysmal hemodynamics. RESULTS: Univariate analysis identified IA as significantly more obtuse in the ruptured subset (124.9 degrees+/-26.5 degrees versus 105.8 degrees+/-18.5 degrees, P=0.0001); similarly, maximal dimension, height-width ratio, and dome-neck aspect ratio were significantly greater in the ruptured subset; multivariate logistic regression identified only IA (P=0.0158) and height-width ratio (P=0.0017), but not maximal dimension or dome-neck aspect ratio, as independent discriminants of rupture status. Computational fluid dynamic analysis showed increasing IA leading to deeper migration of the flow recirculation zone into the aneurysm with higher peak flow velocities and a greater transmission of kinetic energy into the distal portion of the dome. Increasing IA resulted in higher inflow velocity and greater wall shear stress magnitude and spatial gradients in both the inflow zone and dome. CONCLUSIONS: Inflow-angle is a significant discriminant of rupture status in sidewall-type aneurysms and is associated with higher energy transmission to the dome. These results support inclusion of IA in future prospective aneurysm rupture risk assessment trials.

How to WEB: a practical review of methodology for the use of the Woven EndoBridge.

Wide-necked bifurcation aneurysms (WNBAs) make up 26-36% of all brain aneurysms. Treatments for WNBAs pose unique challenges due to the need to preserve major bifurcation vessels while achieving a durable occlusion of the aneurysm. Intrasaccular flow disruption is an innovative technique for the treatment of WNBAs. The Woven EndoBridge (WEB) device is the only United States Food and Drug Administration approved intrasaccular flow disruption device. In this review article we discuss various aspects of treating WNBAs with the WEB device, including indications for use, aneurysm/device selection strategies, antiplatelet therapy requirement, procedural technique, potential complications and bailouts, and management strategies for residual/recurrent aneurysms after initial WEB treatment.

Intravenous thrombolysis pretreatment and other predictors of infarct in a new previously unaffected territory (INT) in ELVO strokes treated with mechanical thrombectomy.

INTRODUCTION: One uncommon complication of mechanical thrombectomy (MT) is an infarct in a new previously unaffected territory (infarct in new territory (INT)). OBJECTIVE: To evaluate the predictors of INT with special focus on intravenous thrombolysis(IVT)pretreatmentbefore MT. METHODS: Consecutive patients with emergent large vessel occlusion (ELVO) treated with MT during a 5-year period were evaluated. INT was defined using standardized methodology proposed by ESCAPE investigators. The predictors of INT and its impact on outcomes were investigated. RESULTS: A total of 419 consecutive patients with ELVO received MT (mean age 64±15 years, 50% men, median baseline National Institutes of Health Stroke Scale score 16 points (IQR 11-20), 69% pretreated with IVT). The incidence of INT was lower in patients treated with combination therapy (IVTandMT) than in patients treated with MT alone, respectively (10% vs 20%; p=0.011). The INT group had more patients with posterior circulation occlusions than the group without INT (28% vs 10%, respectively; p<0.001). The rates of 3-month functional independence were lower in patients with INT (30% vs 50%; p=0.007). IVT pretreatment was not independently related to INT (OR=0.75; 95% CI 0.32 to 1.76), and INT did not emerge as an independent predictor of 3-month functional independence (OR=0.69; 95% CI 0.29 to 1.62) on multivariable logistic regression models. Location of posterior circulation occlusion was independently associated with a higher odds of INT (OR=3.33; 95% CI 1.43 to 7.69; p=0.005). CONCLUSIONS: IVT pretreatment is not independently associated with a lower likelihood of INT in patients with ELVO treated with MT. Patients with ELVO with posterior circulation occlusion are more likely to have INT after MT.