Noncontrast CT Selected Thrombectomy vs Medical Management for Late-Window Anterior Large Vessel Occlusion.

BACKGROUND AND OBJECTIVES: There is uncertainty whether patients with large vessel occlusion (LVO) presenting in the late 6-hour to 24-hour time window can be selected for endovascular therapy (EVT) by noncontrast CT (NCCT) and CT angiography (CTA) for LVO detection. We evaluated the clinical outcomes of patients selected for EVT by NCCT compared with those medically managed in the extended time window. METHODS: This multinational cohort study was conducted at 66 sites across 10 countries. Consecutive patients with proximal anterior LVO stroke selected for EVT by NCCT or medically managed and presenting within 6-24 hours of time last seen well (TSLW) from January 2014 to May 2022 were included. The primary end point was the 90-day ordinal shift in the modified Rankin Scale (mRS) score. Inverse probability treatment weighting (IPTW) and multivariable methods were used. RESULTS: Of 5,098 patients screened, 839 patients were included, with a median (interquartile range) age of 75 (64-83) years; 455 (54.2%) were women. There were 616 patients selected to undergo EVT by NCCT (73.4%) and 223 (26.6%) who were medically managed. In IPTW analyses, there was a more favorable 90-day ordinal mRS shift in patients selected by NCCT to EVT vs those who were medically managed (odds ratio [OR] 1.99, 95% CI 1.53-2.59; p < 0.001). There were higher rates of 90-day functional independence (mRS 0-2) in the EVT group (40.1% vs 18.4%, OR 3.31, 95% CI 2.11-5.20; p < 0.001). sICH was nonsignificantly higher in the EVT group (8.5% vs 1.4%, OR 3.77, 95% CI 0.72-19.7, p = 0.12). Mortality at 90 days was lower in the EVT vs MM group (23.9% vs 32.3%, OR 0.61, 95% CI 0.45-0.83, p = 0.002). DISCUSSION: In patients with proximal anterior LVO in the extended time window, there was a lower rate of disability and mortality in patients selected with NCCT and CTA to EVT compared with those who were medically managed. These findings support the use of NCCT as a simpler and more inclusive approach to patient selection in the extended window. TRIAL REGISTRATION INFORMATION: This study was registered at ClinicalTrials.gov under NCT04096248. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that for patients with proximal anterior circulation occlusion presenting with ischemic stroke from 6 to 24 hours, compared with medical management, those undergoing thrombectomy based on NCCT have reduced disability and mortality at 90 days.

Development and validation of a SCORing systEm for pre-thrombectomy diagnosis of IntraCranial Atherosclerotic Disease (Score-ICAD).

BACKGROUND: Early identification of intracranial atherosclerotic disease (ICAD) may impact the management of patients undergoing mechanical thrombectomy (MT). We sought to develop and validate a scoring system for pre-thrombectomy diagnosis of ICAD in anterior circulation large vessel/distal medium vessel occlusion strokes (LVOs/DMVOs). METHODS: Retrospective analysis of two prospectively maintained comprehensive stroke center databases including patients with anterior circulation occlusions spanning 2010-22 (development cohort) and 2018-22 (validation cohort). ICAD cases were matched for age and sex (1:1) to non-ICAD controls. RESULTS: Of 2870 MTs within the study period, 348 patients were included in the development cohort: 174 anterior circulation ICAD (6% of 2870 MTs) and 174 controls. Multivariable analysis ß coefficients led to a 20 point scale: absence of atrial fibrillation (5); vascular risk factor burden (1) for each of hypertension, diabetes, smoking, and hyperlipidemia; multifocal single artery stenoses on CT angiography (3); absence of territorial cortical infarct (3); presence of borderzone infarct (3); or ipsilateral carotid siphon calcification (2). The validation cohort comprised 56 ICAD patients (4.1% of 1359 MTs): 56 controls. Area under the receiver operating characteristic curve was 0.88 (0.84-0.91) and 0.82 (0.73-0.89) in the development and validation cohorts, respectively. Calibration slope and intercept showed a good fit for the development cohort although with overestimated risk for the validation cohort. After intercept adjustment, the overestimation was corrected (intercept 0, 95% CI -0.5 to -0.5; slope 0.8, 95% CI 0.5 to 1.1). In the full cohort (n=414), ≥11 points showed the best performance for distinguishing ICAD from non-ICAD, with 0.71 (95% CI 0.65 to 0.78) sensitivity and 0.82 (95% CI 0.77 to 0.87) specificity, and 3.92 (95% CI 2.92 to 5.28) positive and 0.35 (95% CI 0.28 to 0.44) negative likelihood ratio. Scores ≥12 showed 90% specificity and 63% sensitivity. CONCLUSION: The proposed scoring system for preprocedural diagnosis of ICAD LVOs and DMVOs presented satisfactory discrimination and calibration based on clinical and non-invasive radiological data.

Outcomes of Bridging Intravenous Thrombolysis Versus Endovascular Therapy Alone in Late-Window Acute Ischemic Stroke.

BACKGROUND: Studies comparing bridging intravenous thrombolysis (IVT) with direct endovascular therapy (EVT) in patients with acute ischemic stroke who present late are limited. We aimed to compare the clinical outcomes and safety of bridging IVT in patients with acute ischemic stroke due to anterior circulation large vessel occlusion who underwent EVT 6 to 24 hours after time last known well. METHODS: We enrolled patients with anterior circulation large vessel occlusion stroke and a National Institutes of Health Stroke Scale score of ≥6 from 20 centers across 10 countries in the multicenter retrospective CLEAR study (CT for Late Endovascular Reperfusion) between January 2014 and May 2022. We used inverse probability of treatment weighting modeling adjusted for clinical and imaging confounders to compare functional outcomes, reperfusion success, symptomatic intracranial hemorrhage, and mortality between EVT patients with and without prior IVT. RESULTS: Of 5098 patients screened for eligibility, we included 2749 patients, of whom 549 received bridging IVT before EVT. The timing of IVT was not recorded. Witnessed stroke onset and transfer rates were higher in the bridging IVT group (25% versus 12% and 77% versus 55%, respectively, P value for both <0.0001), and time intervals between stroke onset and treatment were shorter (time last known well-start of EVT median 560 minutes [interquartile range, 432-791] versus 724 minutes [interquartile range, 544-912]; P<0.0001). After adjustment for confounders, there was no difference in functional outcome at 3 months (adjusted common odds ratio for modified Rankin Scale shift, 1.03 [95% CI, 0.89-1.19]; P=0.72) or successful reperfusion (adjusted odds ratio, 1.19 [95% CI, 0.81-1.75]; P=0.39). There were no safety concerns associated with bridging IVT versus direct EVT (symptomatic intracranial hemorrhage: adjusted odds ratio, 0.75 [95% CI, 0.38-1.48]; P=0.40; mortality: adjusted odds ratio, 1.14 [95% CI, 0.89-1.46]; P=0.31). Results were unchanged when the analysis was limited to patients who received IVT >6 hours after last known well. CONCLUSIONS: In patients with an anterior circulation large vessel occlusion stroke who underwent EVT 6 to 24 hours from last known well, bridging IVT was not associated with a difference in outcomes compared with direct EVT. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04096248.

Endovascular versus medical therapy in posterior cerebral artery stroke: role of baseline NIHSS and occlusion site.

Background: Acute ischemic stroke (AIS) with isolated posterior cerebral artery occlusion (iPCAO) lacks management evidence from randomized trials. We aimed to evaluate whether the association between endovascular treatment (EVT) and outcomes in iPCAO-AIS is modified by initial stroke severity (baseline NIHSS) and arterial occlusion site. Methods: Based on the multicenter, retrospective, case-control study of consecutive iPCAO-AIS patients (PLATO study), we assessed the heterogeneity of EVT outcomes compared to medical management (MM) for iPCAO, according to baseline NIHSS (≤6 vs. >6) and occlusion site (P1 vs. P2), using multivariable regression modelling with interaction terms. The primary outcome was the favorable shift of 3-month mRS. Secondary outcomes included excellent outcome (mRS 0-1), functional independence (mRS 0-2), symptomatic intracranial hemorrhage (sICH) and mortality. Results: From 1344 patients assessed for eligibility, 1,059 were included (median age 74 years, 43.7% women, 41.3% had intravenous thrombolysis), 364 receiving EVT and 695 MM. Baseline stroke severity did not modify the association of EVT with 3-month mRS distribution (pint=0.312), but did with functional independence (pint=0.010), with a similar trend on excellent outcome (pint=0.069). EVT was associated with more favorable outcomes than MM in patients with baseline NIHSS>6 (mRS 0-1: 30.6% vs. 17.7%, aOR=2.01, 95%CI=1.22-3.31; mRS 0-2: 46.1% vs. 31.9%, aOR=1.64, 95%CI=1.08-2.51), but not in those with NIHSS≤6 (mRS 0-1: 43.8% vs. 46.3%, aOR=0.90, 95%CI=0.49-1.64; mRS 0-2: 65.3% vs. 74.3%, aOR=0.55, 95%CI=0.30-1.0). EVT was associated with more sICH regardless of baseline NIHSS (pint=0.467), while the mortality increase was more pronounced in patients with NIHSS≤6 (pint=0.044, NIHSS≤6: aOR=7.95,95%CI=3.11-20.28, NIHSS>6: aOR=1.98,95%CI=1.08-3.65). Arterial occlusion site did not modify the association of EVT with outcomes compared to MM. Conclusion: Baseline clinical stroke severity, rather than the occlusion site, may be an important modifier of the association between EVT and outcomes in iPCAO. Only severely affected patients with iPCAO (NIHSS>6) had more favorable disability outcomes with EVT than MM, despite increased mortality and sICH.

Safety and clinical outcomes of endovascular therapy versus medical management in late presentation of large ischemic stroke.

INTRODUCTION: The benefit of endovascular therapy (EVT) among stroke patients with large ischemic core (ASPECTS 0-5) in the extended time window outside of trial settings remains unclear. We analyzed the effect of EVT among these stroke patients in real-world settings. PATIENTS AND METHODS: The CT for Late Endovascular Reperfusion (CLEAR) study recruited patients from 66 centers in 10 countries between 01/2014 and 05/2022. The extended time-window was defined as 6-24 h from last-seen-well to treatment. The primary outcome was shift of the 3-month modified Rankin scale (mRS) score. Safety outcomes included symptomatic intracranial hemorrhage (sICH) and mortality. Outcomes were analyzed with ordinal and logistic regressions. RESULTS: Among 5098 screened patients, 2451 were included in the analysis (median age 73, 55% women). Of patients with ASPECTS 0-5 (n = 310), receiving EVT (n = 209/310) was associated with lower 3-month mRS when compared to medical management (median 4 IQR 3-6 vs 6 IQR 4-6; aOR 0.4, 95% CI 0.2-0.7). Patients undergoing EVT had higher sICH (11.2% vs 4.0%; aOR 4.1, 95% CI 1.2-18.8) and lower mortality (31.6% vs 58.4%, aOR 0.4; 95% CI 0.2-0.9) compared to medically managed patients. The relative benefit of EVT was comparable between patients with ASPECTS 0 and 5 and 6-10 in the extended time window (interaction aOR 0.9; 95% CI 0.5-1.7). CONCLUSION: In the extended time window, patients with ASPECTS 0-5 may have preserved relative treatment benefit of EVT compared to patients with ASPECTS 6-10. These findings are in line with recent trials showing benefit of EVT among real-world patients with large ischemic core in the extended time window. TRIAL REGISTRATION NUMBER: clinicaltrials.gov; Unique identifier: NCT04096248.

Rescue Therapy for Failed Mechanical Thrombectomy in Acute Ischemic Stroke: A Pooled Analysis of the Society of Vascular and Interventional Neurology Registry.

OBJECTIVE: We aimed to evaluate the association between rescue therapy (RT) and functional outcomes compared to medical management (MM) in patients presenting after failed mechanical thrombectomy (MT). METHODS: This cross-sectional study utilized prospectively collected and maintained data from the Society of Vascular and Interventional Neurology Registry, spanning from 2011 to 2021. The cohort comprised patients with large vessel occlusions (LVOs) with failed MT. The primary outcome was the shift in the degree of disability, as gauged by the modified Rankin Scale (mRS) at 90 days. Additional outcomes included functional independence (90-day mRS score of 0-2), symptomatic intracranial hemorrhage (sICH), and 90-day mortality. RESULTS: Of a total of 7,018 patients, 958 presented failed MT and were included in the analysis. The RT group comprised 407 (42.4%) patients, and the MM group consisted of 551 (57.5%) patients. After adjusting for confounders, the RT group showed a favorable shift in the overall 90-day mRS distribution (adjusted common odds ratio = 1.79, 95% confidence interval [CI] = 1.32-2.45, p < 0.001) and higher rates of functional independence (RT: 28.8% vs MM: 15.7%, adjusted odds ratio [aOR] = 1.93, 95% CI = 1.21-3.07, p = 0.005) compared to the MM group. RT also showed lower rates of sICH (RT: 3.8% vs MM: 9.1%, aOR = 0.52, 95% CI = 0.28-0.97, p = 0.039) and 90-day mortality (RT: 33.4% vs MM: 45.5%, aOR = 0.61, 95% CI = 0.42-0.89, p = 0.009). INTERPRETATION: Our findings advocate for the utilization of RT as a potential treatment strategy for cases of LVO resistant to first-line MT techniques. Prospective studies are warranted to validate these observations and optimize the endovascular approach for failed MT patients. ANN NEUROL 2024.

Miniature battery-free epidural cortical stimulators.

Miniaturized neuromodulation systems could improve the safety and reduce the invasiveness of bioelectronic neuromodulation. However, as implantable bioelectronic devices are made smaller, it becomes difficult to store enough power for long-term operation in batteries. Here, we present a battery-free epidural cortical stimulator that is only 9 millimeters in width yet can safely receive enough wireless power using magnetoelectric antennas to deliver 14.5-volt stimulation bursts, which enables it to stimulate cortical activity on-demand through the dura. The device has digitally programmable stimulation output and centimeter-scale alignment tolerances when powered by an external transmitter. We demonstrate that this device has enough power and reliability for real-world operation by showing acute motor cortex activation in human patients and reliable chronic motor cortex activation for 30 days in a porcine model. This platform opens the possibility of simple surgical procedures for precise neuromodulation.

Early technique switch following failed passes during mechanical thrombectomy for ischemic stroke: should the approach change and when?

BACKGROUND: Fast and complete reperfusion in endovascular therapy (EVT) for ischemic stroke leads to superior clinical outcomes. The effect of changing the technical approach following initially unsuccessful passes remains undetermined. OBJECTIVE: To evaluate the association between early changes to the EVT approach and reperfusion. METHODS: Multicenter retrospective analysis of prospectively collected data for patients who underwent EVT for intracranial internal carotid artery, middle cerebral artery (M1/M2), or basilar artery occlusions. Changes in EVT technique after one or two failed passes with stent retriever (SR), contact aspiration (CA), or a combined technique (CT) were compared with repeating the previous strategy. The primary outcome was complete/near-complete reperfusion, defined as an expanded Thrombolysis in Cerebral Infarction (eTICI) of 2c-3, following the second and third passes. RESULTS: Among 2968 included patients, median age was 66 years and 52% were men. Changing from SR to CA on the second or third pass was not observed to influence the rates of eTICI 2c-3, whereas changing from SR to CT after two failed passes was associated with higher chances of eTICI 2c-3 (OR=5.3, 95% CI 1.9 to 14.6). Changing from CA to CT was associated with higher eTICI 2c-3 chances after one (OR=2.9, 95% CI 1.6 to 5.5) or two (OR=2.7, 95% CI 1.0 to 7.4) failed CA passes, while switching to SR was not significantly associated with reperfusion. Following one or two failed CT passes, switching to SR was not associated with different reperfusion rates, but changing to CA after two failed CT passes was associated with lower chances of eTICI 2c-3 (OR=0.3, 95% CI 0.1 to 0.9). Rates of functional independence were similar. CONCLUSIONS: Early changes in EVT strategies were associated with higher reperfusion and should be contemplated following failed attempts with stand-alone CA or SR.

Middle meningeal artery embolization reduces recurrence following surgery for septated chronic subdural hematomas.

BACKGROUND: Septated chronic subdural hematomas (cSDH) have high rates of recurrence despite surgical evacuation. Middle meningeal artery embolization (MMAE) has emerged as a promising adjuvant for secondary prevention, yet its efficacy remains ill-defined. METHODS: This is a retrospective review of septated cSDH cases treated at our institution. The surgery-only group was derived from cases performed before 2018, and the surgery+MMAE group was derived from cases performed 2018 or later. The primary outcome was reoperation rate. Secondary outcomes were recurrence, change in hematoma thickness, and midline shift. RESULTS: A total of 34 cSDHs in 28 patients (surgery+MMAE) and 95 cSDHs in 83 patients (surgery-only) met the inclusion criteria. No significant difference in baseline characteristics between groups was identified. The reoperation rate was significantly higher in the surgery-only group (n = 16, 16.8%) compared with the surgery+MMAE cohort (n = 0, 0.0%) (p=0.006). A reduced incidence of recurrence (p=0.011) was also seen in the surgery+MMAE group. CONCLUSIONS: MMAE for septated cSDH was found to be highly effective in preventing recurrence and reoperation. MMAE is an adjunct to surgical evacuation may be of particular benefit in this patient cohort.

Anesthetic management for large vessel occlusion acute ischemic stroke with tandem lesions.

BACKGROUND: Endovascular therapy (EVT) stands as an established and effective intervention for acute ischemic stroke in patients harboring tandem lesions (TLs). However, the optimal anesthetic strategy for EVT in TL patients remains unclear. This study aims to evaluate the impact of distinct anesthetic techniques on outcomes in acute ischemic stroke patients presenting with TLs. METHODS: Patient-level data, encompassing cases from 16 diverse centers, were aggregated for individuals with anterior circulation TLs treated between January 2015 and December 2020. A stratification based on anesthetic technique was conducted to distinguish between general anesthesia (GA) and procedural sedation (PS). Multivariable logistic regression models were built to discern the association between anesthetic approach and outcomes, including the favorable functional outcome defined as 90-day modified Rankin Score (mRS) of 0-2, ordinal shift in mRS, symptomatic intracranial hemorrhage (sICH), any hemorrhage, successful recanalization (modified Thrombolysis In Cerebral Infarction (mTICI) score ≥2b), excellent recanalization (mTICI 3), first pass effect (FPE), early neurological improvement (ENI), door-to-groin and recanalization times, intrahospital mortality, and 90-day mortality. RESULTS: Among 691 patients from 16 centers, 595 patients (GA 38.7%, PS 61.3%) were included in the final analysis. There were no significant differences noted in the door-to-groin time (80 (46-117.5) mins vs 54 (21-100), P=0.607) and groin to recanalization time (59 (39.5-85.5) mins vs 54 (38-81), P=0.836) among the groups. The odds of a favorable functional outcome (36.6% vs 52.6%; adjusted OR (aOR) 0.56, 95% CI 0.38 to 0.84, P=0.005) and a favorable shift in the 90-day mRS (aOR 0.71, 95% CI 0.51 to 0.99, P=0.041) were lower in the GA group. No differences were noted for sICH (3.9% vs 4.7%, P=0.38), successful recanalization (89.1% vs 86.5%, P=0.13), excellent recanalization (48.5% vs 50.3%, P=0.462), FPE (53.6% vs 63.4%, P=0.05), ENI (38.9% vs 38.8%, P=0.138), and 90-day mortality (20.3% vs 16.3%, P=0.525). An interaction was noted for favorable functional outcome between the type of anesthesia and the baseline Alberta Stroke Program Early CT Score (ASPECTS) (P=0.033), degree of internal carotid artery (ICA) stenosis (P<0.001), and ICA stenting (P<0.001), and intraparenchymal hematoma between the type of anesthesia and intravenous thrombolysis (P=0.019). In a subgroup analysis, PS showed better functional outcomes in patients with age ≤70 years, National Institutes of Health Stroke Scale (NIHSS) score <15, and acute ICA stenting. CONCLUSIONS: Our findings suggest that the preference for PS not only aligns with comparable procedural safety but is also associated with superior functional outcomes. These results prompt a re-evaluation of current anesthesia practices in EVT, urging clinicians to consider patient-specific characteristics when determining the optimal anesthetic strategy for this patient population.

Strategies to combine 3D vasculature and brain CTA with deep neural networks: Application to LVO.

Automated tools to detect large vessel occlusion (LVO) in acute ischemic stroke patients using brain computed tomography angiography (CTA) have been shown to reduce the time for treatment, leading to better clinical outcomes. There is a lot of information in a single CTA and deep learning models do not have an obvious way of being conditioned on areas most relevant for LVO detection, i.e., the vasculature structure. In this work, we compare and contrast strategies to make convolutional neural networks focus on the vasculature without discarding context information of the brain parenchyma and propose an attention-inspired strategy to encourage this. We use brain CTAs from which we obtain 3D vasculature images. Then, we compare ways of combining the vasculature and the CTA images using a general-purpose network trained to detect LVO. The results show that the proposed strategies allow to improve LVO detection and could potentially help to learn other cerebrovascular-related tasks.

Neurovascular Complications of Iatrogenic Fusarium solani Meningitis.

A multinational outbreak of nosocomial fusarium meningitis occurred among immunocompetent patients who had undergone surgery with epidural anesthesia in Mexico. The pathogen involved had a high predilection for the brain stem and vertebrobasilar arterial system and was associated with high mortality from vessel injury. Effective treatment options remain limited; in vitro susceptibility testing of the organism suggested that it is resistant to all currently approved antifungal medications in the United States. To highlight the severe complications associated with fusarium infection acquired in this manner, we report data, clinical courses, and outcomes from 13 patients in the outbreak who presented with symptoms after a median delay of 39 days.

A self-supervised learning approach for registration agnostic imaging models with 3D brain CTA.

Deep learning-based neuroimaging pipelines for acute stroke typically rely on image registration, which not only increases computation but also introduces a point of failure. In this paper, we propose a general-purpose contrastive self-supervised learning method that converts a convolutional deep neural network designed for registered images to work on a different input domain, i.e., with unregistered images. This is accomplished by using a self-supervised strategy that does not rely on labels, where the original model acts as a teacher and a new network as a student. Large vessel occlusion (LVO) detection experiments using computed tomographic angiography (CTA) data from 402 CTA patients show the student model achieving competitive LVO detection performance (area under the receiver operating characteristic curve [AUC] = 0.88 vs. AUC = 0.81) compared to the teacher model, even with unregistered images. The student model trained directly on unregistered images using standard supervised learning achieves an AUC = 0.63, highlighting the proposed method's efficacy in adapting models to different pipelines and domains.

Sex Differences in Outcomes of Late-Window Endovascular Stroke Therapy.

BACKGROUND: The association between sex and outcome after endovascular thrombectomy of acute ischemic stroke is unclear. The aim of this study was to compare the clinical and safety outcomes between men and women treated with endovascular thrombectomy in the late 6-to-24-hour window period. METHODS: This multicenter, retrospective observational cohort study included consecutive patients who underwent endovascular thrombectomy of anterior circulation stroke in the late window from 66 clinical sites in 10 countries from January 2014 to May 2022. The primary outcome was the 90-day ordinal modified Rankin Scale score. Secondary outcomes included 90-day functional independence (FI), return of Rankin (RoR) to prestroke baseline, FI or RoR, symptomatic intracranial hemorrhage, and mortality. Multivariable and inverse probability of treatment weighting methods were used. We explored the interaction of sex with baseline characteristics on the outcomes ordinal modified Rankin Scale and FI or RoR. RESULTS: Of 1932 patients, 1055 were women and 877 were men. Women were older (77 versus 69 years), had higher rates of atrial fibrillation, hypertension, and greater prestroke disability, but there was no difference in baseline National Institutes of Health Stroke Scale score. Inverse probability of treatment weighting analysis showed no difference between women and men in ordinal modified Rankin Scale (odds ratio, 0.98 [95% CI, 0.79-1.21]), FI or RoR (odds ratio, 0.98 [95% CI, 0.78-1.22]), severe disability or mortality (odds ratio, 0.99 [95% CI, 0.80-1.23]). The multivariable analysis of the above end points was concordant. There were no interactions between baseline characteristics and sex on the outcomes of ordinal modified Rankin Scale and FI or RoR. CONCLUSIONS: In late presenting patients with anterior circulation stroke treated with endovascular thrombectomy in the 6 to 24-hour window, there was no difference in clinical or safety outcomes between men and women.

Endovascular treatment of acute ischemic stroke patients with tandem lesions: antegrade versus retrograde approach.

OBJECTIVE: The optimal technique for treating tandem lesions (TLs) with endovascular therapy is debatable. The authors evaluated the functional, safety, and procedural outcomes of different approaches in a multicenter study. METHODS: Anterior circulation TL patients treated from January 2015 to December 2020 were divided on the basis of antegrade versus retrograde approach and included. The evaluated outcomes were favorable modified Rankin Scale (mRS) score (mRS score 0-2) at 3 months, ordinal shift in mRS score, successful recanalization, excellent recanalization, first-pass effect (FPE), time from groin puncture to successful recanalization, symptomatic intracranial hemorrhage (sICH), and 90-day mortality. RESULTS: Among 691 patients treated at 16 centers, 286 patients (174 antegrade and 112 retrograde approach patients) with acute stenting were included in the final analysis. There were no significant differences in mRS score 0-2 at 90 days (52.2% vs 50.0%, adjusted odds ratio [aOR] 0.83, 95% CI 0.42-1.56, p = 0.54), favorable shift in 90-day mRS score (aOR 1.03, 95% CI 0.66-1.29, p = 0.11), sICH (4.0% vs 4.5%, aOR 0.64, 95% CI 0.24-1.51, p = 0.45), successful recanalization (89.4% vs 93%, aOR 0.49, 95% CI 0.19-1.28, p = 0.19), excellent recanalization (51.4% vs 58.9%, aOR 0.59, 95% CI 0.40-1.07, p = 0.09), FPE (58.3% vs 69.7%, aOR 0.62, 95% CI 0.44-1.15, p = 0.21), and mortality at 90 days (16.6% vs 14.0%, aOR 0.94, 95% CI 0.35-2.44, p = 0.81) between the groups. The median (interquartile range) groin puncture to recanalization time was significantly longer in the antegrade group (59 [43-90] minutes vs 49 [35-73] minutes, p = 0.036). CONCLUSIONS: The retrograde approach was associated with faster recanalization times with a similar functional and safety profile when compared with the antegrade approach in patients with acute ischemic stroke with TL.

Safety Outcomes of Antiplatelet Therapy During Endovascular Treatment of Tandem Lesions in Acute Ischemic Stroke Patients.

Risk of hemorrhage remains with antiplatelet medications required with carotid stenting during endovascular therapy (EVT) for tandem lesion (TLs). We evaluated the safety of antiplatelet regimens in EVT of TLs. This multicenter study included anterior circulation TL patients from 2015 to 2020, stratified by periprocedural EVT antiplatelet strategy: (1) no antiplatelets, (2) single oral, (3) dual oral, and (4) intravenous IV (in combination with single or dual oral). Primary outcome was symptomatic intracranial hemorrhage (sICH). Secondary outcomes were any hemorrhage, favorable functional status (mRS 0-2) at 90 days, successful reperfusion (mTICI score ≥ 2b), in-stent thrombosis, and mortality at 90 days. Of the total 691 patients, 595 were included in the final analysis. One hundred and nineteen (20%) received no antiplatelets, 134 (22.5%) received single oral, 152 (25.5%) dual oral, and 196 (31.9%) IV combination. No significant association was found for sICH (ref: no antiplatelet: 5.7%; single:4.2%; aOR 0.64, CI 0.20-2.06, p = 0.45, dual:1.9%; aOR 0.35, CI 0.09-1.43, p = 0.15, IV combination: 6.1%; aOR 1.05, CI 0.39-2.85, p = 0.92). No association was found for parenchymal or petechial hemorrhage. Odds of successful reperfusion were significantly higher with dual oral (aOR 5.85, CI 2.12-16.14, p = 0.001) and IV combination (aOR 2.35, CI 1.07-5.18, p = 0.035) compared with no antiplatelets. Odds of excellent reperfusion (mTICI 2c/3) were significantly higher for cangrelor (aOR 4.41; CI 1.2-16.28; p = 0.026). No differences were noted for mRS 0-2 at 90 days, in-stent thrombosis, and mortality rates. Administration of dual oral and IV (in combination with single or dual oral) antiplatelets during EVT was associated with significantly increased odds of successful reperfusion without an increased rate of symptomatic hemorrhage or mortality in patients with anterior circulation TLs.

Automated Large Vessel Occlusion Detection Software and Thrombectomy Treatment Times: A Cluster Randomized Clinical Trial.

Importance: The benefit of endovascular stroke therapy (EVT) in large vessel occlusion (LVO) ischemic stroke is highly time dependent. Process improvements to accelerate in-hospital workflows are critical. Objective: To determine whether automated computed tomography (CT) angiogram interpretation coupled with secure group messaging can improve in-hospital EVT workflows. Design, Setting, and Participants: This cluster randomized stepped-wedge clinical trial took place from January 1, 2021, through February 27, 2022, at 4 comprehensive stroke centers (CSCs) in the greater Houston, Texas, area. All 443 participants with LVO stroke who presented through the emergency department were treated with EVT at the 4 CSCs. Exclusion criteria included patients presenting as transfers from an outside hospital (n = 158), in-hospital stroke (n = 39), and patients treated with EVT through randomization in a large core clinical trial (n = 3). Intervention: Artificial intelligence (AI)-enabled automated LVO detection from CT angiogram coupled with secure messaging was activated at the 4 CSCs in a random-stepped fashion. Once activated, clinicians and radiologists received real-time alerts to their mobile phones notifying them of possible LVO within minutes of CT imaging completion. Main Outcomes and Measures: Primary outcome was the effect of AI-enabled LVO detection on door-to-groin (DTG) time and was measured using a mixed-effects linear regression model, which included a random effect for cluster (CSC) and a fixed effect for exposure status (pre-AI vs post-AI). Secondary outcomes included time from hospital arrival to intravenous tissue plasminogen activator (IV tPA) bolus in eligible patients, time from initiation of CT scan to start of EVT, and hospital length of stay. In exploratory analysis, the study team evaluated the impact of AI implementation on 90-day modified Rankin Scale disability outcomes. Results: Among 243 patients who met inclusion criteria, 140 were treated during the unexposed period and 103 during the exposed period. Median age for the complete cohort was 70 (IQR, 58-79) years and 122 were female (50%). Median National Institutes of Health Stroke Scale score at presentation was 17 (IQR, 11-22) and the median DTG preexposure was 100 (IQR, 81-116) minutes. In mixed-effects linear regression, implementation of the AI algorithm was associated with a reduction in DTG time by 11.2 minutes (95% CI, -18.22 to -4.2). Time from CT scan initiation to EVT start fell by 9.8 minutes (95% CI, -16.9 to -2.6). There were no differences in IV tPA treatment times nor hospital length of stay. In multivariable logistic regression adjusted for age, National Institutes of Health Stroke scale score, and the Alberta Stroke Program Early CT Score, there was no difference in likelihood of functional independence (modified Rankin Scale score, 0-2; odds ratio, 1.3; 95% CI, 0.42-4.0). Conclusions and Relevance: Automated LVO detection coupled with secure mobile phone application-based communication improved in-hospital acute ischemic stroke workflows. Software implementation was associated with clinically meaningful reductions in EVT treatment times. Trial Registration: ClinicalTrials.gov Identifier: NCT05838456.

Synthetic OCT-A blood vessel maps using fundus images and generative adversarial networks.

Vessel segmentation in fundus images permits understanding retinal diseases and computing image-based biomarkers. However, manual vessel segmentation is a time-consuming process. Optical coherence tomography angiography (OCT-A) allows direct, non-invasive estimation of retinal vessels. Unfortunately, compared to fundus images, OCT-A cameras are more expensive, less portable, and have a reduced field of view. We present an automated strategy relying on generative adversarial networks to create vascular maps from fundus images without training using manual vessel segmentation maps. Further post-processing used for standard en face OCT-A allows obtaining a vessel segmentation map. We compare our approach to state-of-the-art vessel segmentation algorithms trained on manual vessel segmentation maps and vessel segmentations derived from OCT-A. We evaluate them from an automatic vascular segmentation perspective and as vessel density estimators, i.e., the most common imaging biomarker for OCT-A used in studies. Using OCT-A as a training target over manual vessel delineations yields improved vascular maps for the optic disc area and compares to the best-performing vessel segmentation algorithm in the macular region. This technique could reduce the cost and effort incurred when training vessel segmentation algorithms. To incentivize research in this field, we will make the dataset publicly available to the scientific community.

Rescue intracranial stenting for failed posterior circulation thrombectomy: analysis from the Stenting and Angioplasty in NeuroThrombectomy (SAINT) study.

BACKGROUNDS: Recent trials have shown improved outcomes after mechanical thrombectomy (MT) for vertebrobasilar occlusion (VBO) stroke. However, there is a paucity of data regarding safety and outcomes of rescue intracranial stenting (RS) after failed MT (FRRS+) for posterior circulation stroke. We sought to compare RS to failed reperfusion without RS (FRRS-). METHODS: This is a retrospective analysis of the Stenting and Angioplasty in NeuroThrombectomy (SAINT) study, a multicenter collaboration involving prospectively collected databases. Patients were included if they had posterior circulation stroke and failed MT. The cohort was divided into two groups: FRRS+ and FRRS- (defined as modified Thrombolysis In Cerebral Infarction (mTICI) score 0-2a). The primary outcome was a shift in the degree of disability as measured by the modified Rankin Scale (mRS) at 90 days. Secondary outcomes included mRS 0-2 and mRS 0-3 at 90 days. Safety measures included rates of symptomatic intracranial hemorrhage (sICH), procedural complications, and 90-day mortality. Sensitivity and subgroup analyses were performed to identify outcomes in a matched cohort and in those with VBO, respectively. RESULTS: A total of 152 failed thrombectomies were included in the analysis. FRRS+ (n=84) was associated with increased likelihood of lower disability (acOR 2.24, 95% CI 1.04 to 4.95, P=0.04), higher rates of mRS 0-2 (26.8% vs 12.5%, aOR 4.43, 95% CI 1.22 to 16.05, P=0.02) and mRS 0-3 (35.4% vs 18.8%, aOR 3.13, 95% CI 1.08 to 9.10, P=0.036), and lower mortality (42.7% vs 59.4%, aOR 0.40, 95% CI 0.17 to 0.97, P=0.04) at 90 days compared with FRRS- (n=68). The rates of sICH and procedural complications were comparable between the groups. Sensitivity and subgroup analyses showed similar results. CONCLUSION: In patients with posterior circulation stroke who had failed MT, RS resulted in better functional outcomes with comparable safety profile to procedure termination.