Assessment of Thrombectomy versus Combined Thrombolysis and Thrombectomy in Patients with Acute Ischemic Stroke and Medium Vessel Occlusion.

Background The combination of intravenous thrombolysis (IVT) with mechanical thrombectomy (MT) may have clinical benefits for patients with medium vessel occlusion. Purpose To examine whether MT combined with IVT is associated with different outcomes than MT alone in patients with acute ischemic stroke (AIS) and medium vessel occlusion. Materials and Methods This retrospective study included consecutive adult patients with AIS and medium vessel occlusion treated with MT or MT with IVT at 37 academic centers in North America, Asia, and Europe. Data were collected from September 2017 to July 2021. Propensity score matching was performed to reduce confounding. Univariable and multivariable logistic regression analyses were performed to test the association between the addition of IVT treatment and different functional and safety outcomes. Results After propensity score matching, 670 patients (median age, 75 years [IQR, 64-82 years]; 356 female) were included in the analysis; 335 underwent MT alone and 335 underwent MT with IVT. Median onset to puncture (350 vs 210 minutes, P < .001) and onset to recanalization (397 vs 273 minutes, P < .001) times were higher in the MT group than the MT with IVT group, respectively. In the univariable regression analysis, the addition of IVT was associated with higher odds of a modified Rankin Scale (mRS) score 0-2 (odds ratio [OR], 1.44; 95% CI: 1.06, 1.96; P = .019); however, this association was not observed in the multivariable analysis (OR, 1.37; 95% CI: 0.99, 1.89; P = .054). In the multivariable analysis, the addition of IVT also showed no evidence of an association with the odds of first-pass effect (OR, 1.27; 95% CI: 0.9, 1.79; P = .17), Thrombolysis in Cerebral Infarction grades 2b-3 (OR, 1.64; 95% CI: 0.99, 2.73; P = .055), mRS scores 0-1 (OR, 1.27; 95% CI: 0.91, 1.76; P = .16), mortality (OR, 0.78; 95% CI: 0.49, 1.24; P = .29), or intracranial hemorrhage (OR, 1.25; 95% CI: 0.88, 1.76; P = .21). Conclusion Adjunctive IVT may not provide benefit to MT in patients with AIS caused by distal and medium vessel occlusion. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Wojak in this issue.

Endovascular therapy versus best medical management in distal medium middle cerebral artery acute ischaemic stroke: a multinational multicentre propensity score-matched study.

BACKGROUND: The efficacy of endovascular treatment (EVT) in acute ischaemic stroke due to distal medium vessel occlusion (DMVO) remains uncertain. Our study aimed to evaluate the safety and efficacy of EVT compared with the best medical management (BMM) in DMVO. METHODS: In this prospectively collected, retrospectively reviewed, multicentre cohort study, we analysed data from the Multicentre Analysis of primary Distal medium vessel occlusions: effect of Mechanical Thrombectomy registry. Patients with acute ischaemic stroke due to DMVO in the M2, M3 and M4 segments who underwent EVT or received BMM were included. Primary outcome measures comprised 10 co-primary endpoints, including functional independence (mRS 0-2), excellent outcome (mRS 0-1), mortality (mRS 6) and haemorrhagic complications. Propensity score matching was employed to balance the cohorts. RESULTS: Among 2125 patients included in the primary analysis, 1713 received EVT and 412 received BMM. After propensity score matching, each group comprised 391 patients. At 90 days, no significant difference was observed in achieving mRS 0-2 between EVT and BMM (adjusted OR 1.00, 95% CI 0.67 to 1.50, p>0.99). However, EVT was associated with higher rates of symptomatic intracerebral haemorrhage (8.4% vs 3.0%, adjusted OR 3.56, 95% CI 1.69 to 7.48, p<0.001) and any intracranial haemorrhage (37% vs 19%, adjusted OR 2.61, 95% CI 1.81 to 3.78, p<0.001). Mortality rates were similar between groups (13% in both, adjusted OR 1.48, 95% CI 0.87 to 2.51, p=0.15). CONCLUSION: Our findings suggest that while EVT does not significantly improve functional outcomes compared with BMM in DMVO, it is associated with higher risks of haemorrhagic complications. These results support a cautious approach to the use of EVT in DMVO and highlight the need for further prospective randomised trials to refine treatment strategies.

Use of the pRESET LITE thrombectomy device in combined approach for medium vessel occlusions: A multicenter evaluation.

PURPOSE: Our purpose was to assess the efficacy and safety of the pRESET LITE stent retriever (Phenox, Bochum, Germany), designed for medium vessel occlusion (MeVO) in acute ischemic stroke (AIS) patients with a primary MeVO. METHODS: We performed a retrospective analysis of the MAD MT Consortium, an integration of prospectively maintained databases at 37 academic institutions in Europe, North America, and Asia, of AIS patients who underwent mechanical thrombectomy with the pRESET LITE stent retriever for a primary MeVO. We subcategorized occlusions into proximal MeVOs (segments A1, M2, and P1) vs. distal MeVOs/DMVO (segments A2, M3-M4, and P2). We reviewed patient and procedural characteristics, as well as angiographic and clinical outcomes. RESULTS: Between September 2016 and December 2021, 227 patients were included (50% female, median age 78 [65-84] years), of whom 161 (71%) suffered proximal MeVO and 66 (29%) distal MeVO. Using a combined approach in 96% of cases, successful reperfusion of the target vessel (mTICI 2b/2c/3) was attained in 85% of proximal MeVO and 97% of DMVO, with a median of 2 passes (IQR: 1-3) overall. Periprocedural complications rate was 7%. Control CT at day 1 post-MT revealed a hemorrhagic transformation in 63 (39%) patients with proximal MeVO and 24 (36%) patients with DMVO, with ECASS-PH type hemorrhagic transformations occurring in 3 (1%) patients. After 3 months, 58% of all MeVO and 63% of DMVO patients demonstrated a favorable outcome (mRS 0-2). CONCLUSION: Mechanical thrombectomy using the pRESET LITE in a combined approach with an aspiration catheter appears effective for primary medium vessel occlusions across several centers and physicians.

Treatment of large intracranial aneurysms using the Woven EndoBridge (WEB): a propensity score-matched analysis.

The Woven EndoBridge (WEB) device is primarily used for treating wide-neck intracranial bifurcation aneurysms under 10 mm. Limited data exists on its efficacy for large aneurysms. We aim to assess angiographic and clinical outcomes of the WEB device in treating large versus small aneurysms. We conducted a retrospective review of the WorldWide WEB Consortium database, from 2011 to 2022, across 30 academic institutions globally. Propensity score matching (PSM) was employed to compare small and large aneurysms on baseline characteristics. A total of 898 patients were included. There was no significant difference observed in clinical presentations, smoking status, pretreatment mRS, presence of multiple aneurysms, bifurcation location, or prior treatment between the two groups. After PSM, 302 matched pairs showed significantly lower last follow-up adequate occlusion rates (81% vs 90%, p = 0.006) and higher retreatment rates (12% vs 3.6%, p < 0.001) in the large aneurysm group. These findings may inform treatment decisions and patient counseling. Future studies are needed to further explore this area.

Dual Layer vs Single Layer Woven EndoBridge Device in the Treatment of Intracranial Aneurysms: A Propensity Score-Matched Analysis.

BACKGROUND: The Woven EndoBridge (WEB) devices have been used for treating wide neck bifurcation aneurysms (WNBAs) with several generational enhancements to improve clinical outcomes. The original device dual-layer (WEB DL) was replaced by a single-layer (WEB SL) device in 2013. This study aimed to compare the effectiveness and safety of these devices in managing intracranial aneurysms. METHODS: A multicenter cohort study was conducted, and data from 1,289 patients with intracranial aneurysms treated with either the WEB SL or WEB DL devices were retrospectively analyzed. Propensity score matching was utilized to balance the baseline characteristics between the two groups. Outcomes assessed included immediate occlusion rate, complete occlusion at last follow-up, retreatment rate, device compaction, and aneurysmal rupture. RESULTS: Before propensity score matching, patients treated with the WEB SL had a significantly higher rate of complete occlusion at the last follow-up and a lower rate of retreatment. After matching, there was no significant difference in immediate occlusion rate, retreatment rate, or device compaction between the WEB SL and DL groups. However, the SL group maintained a higher rate of complete occlusion at the final follow-up. Regression analysis showed that SL was associated with higher rates of complete occlusion (OR: 0.19; CI: 0.04 to 0.8, p = 0.029) and lower rates of retreatment (OR: 0.12; CI: 0 to 4.12, p = 0.23). CONCLUSION: The WEB SL and DL devices demonstrated similar performances in immediate occlusion rates and retreatment requirements for intracranial aneurysms. The SL device showed a higher rate of complete occlusion at the final follow-up.

Off-Label use of Woven EndoBridge device for intracranial brain aneurysm treatment: Modeling of occlusion outcome.

INTRODUCTION: The Woven EndoBridge (WEB) device is emerging as a novel therapy for intracranial aneurysms, but its use for off-label indications requires further study. Using machine learning, we aimed to develop predictive models for complete occlusion after off-label WEB treatment and to identify factors associated with occlusion outcomes. METHODS: This multicenter, retrospective study included 162 patients who underwent off-label WEB treatment for intracranial aneurysms. Baseline, morphological, and procedural variables were utilized to develop machine-learning models predicting complete occlusion. Model interpretation was performed to determine significant predictors. Ordinal regression was also performed with occlusion status as an ordinal outcome from better (Raymond Roy Occlusion Classification [RROC] grade 1) to worse (RROC grade 3) status. Odds ratios (OR) with 95 % confidence intervals (CI) were reported. RESULTS: The best performing model achieved an AUROC of 0.8 for predicting complete occlusion. Larger neck diameter and daughter sac were significant independent predictors of incomplete occlusion. On multivariable ordinal regression, higher RROC grades (OR 1.86, 95 % CI 1.25-2.82), larger neck diameter (OR 1.69, 95 % CI 1.09-2.65), and presence of daughter sacs (OR 2.26, 95 % CI 0.99-5.15) were associated with worse aneurysm occlusion after WEB treatment, independent of other factors. CONCLUSION: This study found that larger neck diameter and daughter sacs were associated with worse occlusion after WEB therapy for aneurysms. The machine learning approach identified anatomical factors related to occlusion outcomes that may help guide patient selection and monitoring with this technology. Further validation is needed.

Comparison of 4-factor PCC reversal of apixaban and rivaroxaban versus warfarin for intracranial hemorrhage.

The purpose of this study is to assess efficacy of 4-factor prothrombin complex concentrates (4F-PCC) for direct oral anticoagulant (DOAC)-associated intracranial hemorrhage (ICH) as compared to its use in warfarin-associated ICH. A retrospective cohort study was performed to compare the efficacy of 4F-PCC for reversal of apixaban and rivaroxaban versus warfarin for ICH at Cooper University Health Care from January 2015 to December 2019. Patients included were ≥ 18 years of age who developed an ICH while on apixaban, rivaroxaban, or warfarin. The primary outcome was to compare the percentage of patients with Excellent or Good hemostatic efficacy after 4F-PCC administration. Secondary outcomes were to describe functional outcomes at discharge, in-hospital mortality, and thrombotic complications after 4F-PCC administration. A total of 159 patients were included; 115 patients received warfarin and 44 patients received a DOAC (apixaban, n = 22; rivaroxaban, n = 22). 70 patients were evaluable for the primary endpoint. Thirty-four (66.7%) patients in the warfarin group versus 14 (73.7%) patients in the DOAC group were determined to have excellent or good hemostatic efficacy (p = 0.57). In-hospital mortality (30.4% vs. 40.9%, p = 0.21) and thrombotic complications (9.6% vs. 11.4%, p = 0.67) were comparable between the warfarin vs. DOAC groups, respectively. This small, retrospective study found no difference in patients with excellent/good hemostatic efficacy after reversal with 4F-PCC for DOAC-associated ICH compared to warfarin-associated ICH. This study is limited by its retrospective nature and sample size. Larger, prospective studies are needed to further determine the efficacy of 4F-PCC in reversing DOAC-associated ICH.

Surgical management of stylocarotid Eagle syndrome in a patient with bilateral internal carotid artery dissection: illustrative case.

BACKGROUND: Eagle syndrome is characterized by an elongated styloid process, which can cause acute neurological symptoms when the projection impinges on local structures. One method by which Eagle syndrome can cause acute stroke is via internal carotid artery dissection. OBSERVATIONS: A patient presented with acute aphasia and right-arm weakness. Imaging revealed a left internal carotid artery dissection, which was treated with stenting. Three years later, the patient presented with left-sided weakness, and imaging revealed a new right internal carotid artery dissection. Closer review of the patient's imaging revealed bilateral elongated styloid processes. The patient subsequently underwent staged bilateral styloidectomy and returned to his prior baseline postoperatively. LESSONS: This case report describes a patient with Eagle syndrome who had two internal carotid artery dissections separated by several years. A literature review revealed that styloidectomy is well tolerated in patients with carotid dissection due to Eagle syndrome. Patients with carotid dissection due to Eagle syndrome remain at risk for contralateral dissection, and prophylactic contralateral styloidectomy should be considered.

Correlating Age and Hematoma Volume with Extent of Midline Shift in Acute Subdural Hematoma Patients: Validation of an Artificial Intelligence Tool for Volumetric Analysis.

OBJECTIVE: Decision for intervention in acute subdural hematoma patients is based on a combination of clinical and radiographic factors. Age has been suggested as a factor to be strongly considered when interpreting midline shift (MLS) and hematoma volume data for assessing critical clinical severity during operative intervention decisions for acute subdural hematoma patients. The objective of this study was to demonstrate the use of an automated volumetric analysis tool to measure hematoma volume and MLS and quantify their relationship with age. METHODS: A total of 1789 acute subdural hematoma patients were analyzed using qER-Quant software (Qure.ai, Mumbai, India) for MLS and hematoma volume measurements. Univariable and multivariable regressions analyzed association between MLS, hematoma volume, age, and MLS:hematoma volume ratio. RESULTS: In comparison to young patients (≤ 70 years), old patients (>70 years) had significantly higher average hematoma volume (old: 62.2 mL vs. young 46.8 mL, P < 0.0001), lower average MLS (old: 6.6 mm vs. young: 7.4 mm, P = 0.025), and lower average MLS:hematoma volume ratio (old: 0.11 mm/mL vs. young 0.15 mm/mL, P < 0.0001). Young patients had an average of 1.5 mm greater MLS for a given hematoma volume in comparison to old patients. With increasing age, the ratio between MLS and hematoma volume significantly decreases (P = 0.0002). CONCLUSIONS: Commercially available, automated, artificial intelligence (AI)-based tools may be used for obtaining quantitative radiographic measurement data in patients with acute subdural hematoma. Our quantitative results are consistent with the qualitative relationship previously established between age, hematoma volume, and MLS, which supports the validity of using AI-based tools for acute subdural hematoma volume estimation.

Early Experience With Artificial Intelligence Software to Detect Intracranial Occlusive Stroke in Trauma Patients.

Objective Identifying ischemic stroke is a diagnostic challenge in the trauma subpopulation. We describe our early experience with artificial intelligence-assisted image analysis software for automatically identifying acute ischemic stroke in trauma patients.  Methods Patients were retrospectively screened for (i) admission to the trauma service at a level one trauma center between 2020 and 2022, (ii) radiologist-confirmed intracranial occlusion, (iii) occlusion identified on computed tomography angiography performed within 24 hours of admission, (iv) no intracranial hemorrhage, and (v) contemporaneous analysis with the large vessel occlusion (LVO) detection program. Baseline characteristics, stroke detection, response-activation, and outcome data were summarized.  Results Of 9893 trauma patients admitted, 88 (0.89%) patients had a cerebral stroke diagnosis, of which 10 patients (10/88; 11.4%) met inclusion criteria. Most patients were admitted following a fall (8/10; 80%). Six (6/10; 60.0%) patients had LVOs. The program correctly detected 83.3% (5/6) of patients, and these patients were triaged in less than one hour from arrival on average. The program did not falsely identify non-LVOs as LVOs for any patients. Conclusions Identifying adjunct tools to aid timely identification and treatment of ischemic stroke in trauma patients is necessary to increase the chances for meaningful neurological recovery. Our early experience exhibited potential for using automated software to aid occlusion identification and subsequent stroke team mobilization. Future studies in larger cohorts will expand upon these preliminary findings to establish the accuracy and clinical benefit of automated stroke detection tool integration for the trauma population.

Hyperacute thrombosis of a vertebral artery stent with a single missed dose of a P2Y12 inhibitor and poor stent wall apposition: illustrative case.

BACKGROUND: Iatrogenic vertebral artery injury during surgery can cause pseudoaneurysm, hemorrhage, thrombosis, ischemia, or death. Strategies to prevent cerebrovascular embolic complications include surgical ligation, endovascular stenting, and/or antiplatelet therapy. OBSERVATIONS: A 73-year-old female with a known right vertebral artery occlusion underwent a C2-3 laminectomy, complicated by left vertebral artery injury and occlusion with subsequent posterior circulation ischemia. She underwent immediate angioplasty and stenting of the injured artery with undersized drug-eluting stents. Dual antiplatelet therapy of aspirin 81 mg daily and ticagrelor 90 mg twice daily was initiated. On two occasions, more than 6 months after stenting, holding a single ticagrelor dose led to in-stent thrombosis and embolic stroke within hours of the missed dose. Lifelong therapy with ticagrelor was favored over further procedural intervention. LESSONS: It is recommended to prioritize optimal wall stent apposition with oversized stents in patients without collateral circulation. The risk of thromboembolism due to poorly apposed stents is very high, even in delayed (> 6 months) settings. Stent construct revision or bypass grafting may not be feasible or desirable options. For patients without wall apposition, endothelialization may not occur, necessitating lifelong P2Y12 inhibitor therapy to prevent recurrent thromboembolic events. https://thejns.org/doi/10.3171/CASE24296.

A prospective, randomized, controlled, interventional clinical trial to evaluate the safety and efficacy of the medical monopoint reperfusion system for aspiration thrombectomy in acute ischemic stroke patients (SUMMIT MAX): Trial rationale and design.

BACKGROUND: Treatment of large vessel occlusion (LVO) using mechanical thrombectomy with or without intravenous thrombolysis has demonstrated better outcomes compared to medical treatment alone. Large-bore aspiration catheters have been recently introduced. Their effectiveness and safety have not been demonstrated in a randomized trial. The SUMMIT MAX study is designed to address this question. METHODS: SUMMIT MAX is a randomized controlled trial where the effectiveness and safety of the large-bore Monopoint Reperfusion system (Route 92 Medical, San Mateo, CA), will be compared to the currently largest available FDA-cleared aspiration thrombectomy device the AXS Vecta Aspiration system (Stryker Neurovascular, Fremont, CA). The study is a multi-center, prospective, randomized, controlled, interventional, open label clinical trial. The hypothesis is that the effectiveness measured by the recanalization rate (modified thrombolysis in cerebrovascular infarction - mTICI) and safety measured by symptomatic intracranial hemorrhage rate (sICH) of the medical monopoint reperfusion system is non-inferior to the AXS Vecta Aspiration system. RESULTS: Up to 250 subjects are enrolled with at least 50% of subjects enrolled by US sites. The primary effectiveness endpoint is successful arterial revascularization defined as an mTICI score ≥ 2b after use of the assigned device adjudicated by an independent core lab. The primary safety endpoint is defined as sICH within 24 h (-8/+24) post-procedure. Secondary endpoints include successful arterial revascularization defined as a mTICI score ≥ 2b after use of the assigned device with or without adjunctive therapy; device-related serious adverse events; all asymptomatic hemorrhages; time from groin puncture to final angiogram; and rate of first pass effect defined as mTICI 2b after first pass with the assigned device stratified by age (≤85, ≥ 86). CONCLUSION: SUMMIT MAX is a randomized controlled trial comparing the effectiveness and safety of a new large bore class of aspiration devices to the currently largest FDA-cleared aspiration device available.

FreeClimb 88 catheter with Tenzing 8 delivery for contact aspiration mechanical thrombectomy of anterior circulation large vessel occlusions.

PURPOSE: Contact aspiration mechanical thrombectomy (CAMT) with 0.088-inch catheters may improve first-pass success rates, but delivery of such catheters can be challenging and limit effectiveness. This study examines the initial multicenter experience using the FreeClimb 88 catheter paired with the Tenzing 8 delivery catheter. MATERIALS AND METHODS: Retrospective analysis was performed of consecutive patients with large vessel occlusion (LVO) of the internal carotid artery (ICA) or M1 segment of the middle cerebral artery treated with off-label CAMT using the FreeClimb 88 and Tenzing 8 at eight sites participating in the early limited release for these devices. Demographic and procedural variables were collected and analyzed with descriptive statistics and multivariable analysis. RESULTS: Fifty-three consecutive patients were treated. Large vessel occlusion was located in the ICA in 19/53 (35.8%) patients; 34/53 (64.2%) were in the M1 segment. FreeClimb 88 was successfully delivered to the site of occlusion in 50/53 (94.3%) of patients. First-pass TICI 2c or 3 was achieved with FreeClimb 88 delivered by Tenzing 8 in 36 (67.9%) cases. Among cases with successful FreeClimb 88 delivery 9/50 (18.0%) required additional smaller devices to perform thrombectomy of distal occlusions after recanalization of the initial LVO. No complications or symptomatic hemorrhages occurred following thrombectomy. CONCLUSION: Contact aspiration mechanical thrombectomy performed for ICA or M1 LVOs using FreeClimb 88 delivered with Tenzing 8 was safe, effective, and efficient in this early experience, with first-pass TICI 2c or 3 was achieved in 68% of patients without procedural complications occurring in any cases.

"Chopperlysis": The effect of helicopter transport on reperfusion and outcomes in large vessel occlusion strokes.

BACKGROUND: In large vessel occlusion (LVO) stroke patients transferred to a comprehensive stroke center for thrombectomy, spontaneous reperfusion may occur during transport, and anecdotally more frequently in patients transferred via helicopter than by ground. This pattern has been more often observed in conjunction with tenecteplase (TNK) treatment prior to helicopter transport. We aim to explore the "chopperlysis" effect-how helicopter transport, particularly with thrombolytics, may affect reperfusion and clinical outcomes. METHODS: A single thrombectomy capable center (TCC) registry of stroke patients was retrospectively reviewed. Included LVO patients were those who had been transferred to the TCC and received a digital subtraction angiography (DSA) upon arrival. The outcomes were rates of spontaneous reperfusion, distal clot migration, and 90-day good functional outcome. Data were summarized, and endpoints were compared between patients stratified by transport method and/or TNK treatment. RESULTS: Of 270 patients included, helicopter transport was associated with a higher rate of spontaneous reperfusion, particularly among patients not treated with TNK (p < 0.001). There was no significant difference in prevalence of distal clot migration between any subgroups (p > 0.37). Overall, TNK-treated patients had better functional outcomes, and this difference persisted exclusively in the helicopter-transported patients (p = 0.02). CONCLUSION: Helicopter transport was associated with a higher rate of spontaneous reperfusion. There is a potentially synergistic effect between TNK administration and helicopter transport, augmenting thrombolysis and improving long-term outcomes. Further analyses in larger cohorts may expand our understanding of this "chopperlysis" effect.

First pass effect as an independent predictor of functional outcomes in medium vessel occlusions: An analysis of an international multicenter study.

INTRODUCTION: First pass effect (FPE), achievement of complete recanalization (mTICI 2c/3) with a single pass, is a significant predictor of favorable outcomes for endovascular treatment (EVT) in large vessel occlusion stroke (LVO). However, data concerning the impact on functional outcomes and predictors of FPE in medium vessel occlusions (MeVO) are scarce. PATIENTS AND METHODS: We conducted an international retrospective study on MeVO cases. Multivariable logistic modeling was used to establish independent predictors of FPE. Clinical and safety outcomes were compared between the two study groups (FPE vs non-FPE) using logistic regression models. Good outcome was defined as modified Rankin Scale 0-2 at 3 months. RESULTS: Eight hundred thirty-six patients with a final mTICI ⩾ 2b were included in this analysis. FPE was observed in 302 patients (36.1%). In multivariable analysis, hypertension (aOR 1.55, 95% CI 1.10-2.20) and lower baseline NIHSS score (aOR 0.95, 95% CI 0.93-0.97) were independently associated with an FPE. Good outcomes were more common in the FPE versus non-FPE group (72.8% vs 52.8%), and FPE was independently associated with favorable outcome (aOR 2.20, 95% CI 1.59-3.05). 90-day mortality and intracranial hemorrhage (ICH) were significantly lower in the FPE group, 0.43 (95% CI, 0.25-0.72) and 0.55 (95% CI, 0.39-0.77), respectively. CONCLUSION: Over 2/3 of patients with MeVOs and FPE in our cohort had a favorable outcome at 90 days. FPE is independently associated with favorable outcomes, it may reduce the risk of any intracranial hemorrhage, and 3-month mortality.

Defining ideal middle cerebral artery bifurcation aneurysm size for Woven EndoBridge embolization.

OBJECTIVE: The Woven EndoBridge (WEB) device was approved to treat wide-necked bifurcation aneurysms. The device is designed as an intrasaccular flow disruptor covering aneurysm widths up to 10 mm. Although prior studies combined all aneurysm sizes, it is known that aneurysms behave differently in response to endovascular treatment based on their size. Therefore, the authors' objective was to identify ideal middle cerebral artery (MCA) aneurysm width and neck sizes most suitable for WEB treatment. METHODS: The WorldWideWEB consortium is a large multicenter retrospective database that analyzes intracranial aneurysms treated with the WEB device. In this study, all unruptured MCA bifurcation aneurysms with available measurements were included. Cutoff values based on aneurysm width and neck in relation to aneurysm occlusion status were measured using the receiver operating characteristic (ROC) curve. Propensity score matching (PSM) was then used to compare treatment outcomes between aneurysms smaller and larger than the cutoff value for both width and neck size. RESULTS: The ideal cutoff values for MCA bifurcation aneurysm width and neck were 6.1 mm and 4.6 mm, respectively. On PSM, 87 matched pairs were compared based on width size (≤ 6.1 mm and > 6.1 mm), and 77 matched pairs were compared based on neck size (≤ 4.6 mm and > 4.6 mm). There was a significant difference in adequate aneurysm occlusion between aneurysms smaller and larger than those cutoff values for both widths (93% vs 76%, p = 0.0017) and neck sizes (90% vs 70%, p = 0.0026). The retreatment rate was also significantly higher for larger aneurysms in both parameters. CONCLUSIONS: This study shows that MCA bifurcation aneurysms ≤ 6.1 mm in width and ≤ 4.6 mm in neck size are significantly better candidates for WEB treatment, leading to improved occlusion status and reduced retreatment rate, which are important considerations when using WEB devices.

Mechanical Thrombectomy Versus Intravenous Thrombolysis in Distal Medium Vessel Acute Ischemic Stroke: A Multinational Multicenter Propensity Score-Matched Study.

BACKGROUND AND PURPOSE: The management of acute ischemic stroke (AIS) due to distal medium vessel occlusion (DMVO) remains uncertain, particularly in comparing the effectiveness of intravenous thrombolysis (IVT) plus mechanical thrombectomy (MT) versus IVT alone. This study aimed to evaluate the safety and efficacy in DMVO patients treated with either MT-IVT or IVT alone. METHODS: This multinational study analyzed data from 37 centers across North America, Asia, and Europe. Patients with AIS due to DMVO were included, with data collected from September 2017 to July 2023. The primary outcome was functional independence, with secondary outcomes including mortality and safety measures such as types of intracerebral hemorrhage. RESULTS: The study involved 1,057 patients before matching, and 640 patients post-matching. Functional outcomes at 90 days showed no significant difference between groups in achieving good functional recovery (modified Rankin Scale 0-1 and 0-2), with adjusted odds ratios (OR) of 1.21 (95% confidence interval [CI] 0.81 to 1.79; P=0.35) and 1.00 (95% CI 0.66 to 1.51; P>0.99), respectively. Mortality rates at 90 days were similar between the two groups (OR 0.75, 95% CI 0.44 to 1.29; P=0.30). The incidence of symptomatic intracerebral hemorrhage was comparable, but any type of intracranial hemorrhage was significantly higher in the MT-IVT group (OR 0.43, 95% CI 0.29 to 0.63; P<0.001). CONCLUSION: The results of this study indicate that while MT-IVT and IVT alone show similar functional and mortality outcomes in DMVO patients, MT-IVT presents a higher risk of hemorrhagic complications, thus MT-IVT may not routinely offer additional benefits over IVT alone for all DMVO stroke patients. Further prospective randomized trials are needed to identify patient subgroups most likely to benefit from MT-IVT treatment in DMVO.

Association of preprocedural antiplatelet use with decreased thromboembolic complications for intracranial aneurysms undergoing intrasaccular flow disruption.

OBJECTIVE: This study was conducted to investigate the impact of antiplatelet administration in the periprocedural period on the occurrence of thromboembolic complications (TECs) in patients undergoing treatment using the Woven EndoBridge (WEB) device for intracranial wide-necked bifurcation aneurysms. The primary objective was to assess whether the use of antiplatelets in the pre- and postprocedural phases reduces the likelihood of developing TECs, considering various covariates. METHODS: A retrospective multicenter observational study was conducted within the WorldWideWEB Consortium and comprised 38 academic centers with endovascular treatment capabilities. Univariable and multivariable logistic regression analyses were performed to determine the association between antiplatelet use and TECs, adjusting for covariates. Missing predictor data were addressed using multiple imputation. RESULTS: The study comprised two cohorts: one addressing general thromboembolic events and consisting of 1412 patients, among whom 103 experienced TECs, and another focusing on symptomatic thromboembolic events and comprising 1395 patients, of whom 50 experienced symptomatic TECs. Preprocedural antiplatelet use was associated with a reduced likelihood of overall TECs (OR 0.32, 95% CI 0.19-0.53, p < 0.001) and symptomatic TECs (OR 0.49, 95% CI 0.25-0.95, p = 0.036), whereas postprocedural antiplatelet use showed no significant association with TECs. The study also revealed additional predictors of TECs, including stent use (overall: OR 4.96, 95% CI 2.38-10.3, p < 0.001; symptomatic: OR 3.24, 95% CI 1.26-8.36, p = 0.015), WEB single-layer sphere (SLS) type (overall: OR 0.18, 95% CI 0.04-0.74, p = 0.017), and posterior circulation aneurysm location (symptomatic: OR 18.43, 95% CI 1.48-230, p = 0.024). CONCLUSIONS: The findings of this study suggest that the preprocedural administration of antiplatelets is associated with a reduced likelihood of TECs in patients undergoing treatment with the WEB device for wide-necked bifurcation aneurysms. However, postprocedural antiplatelet use did not show a significant impact on TEC occurrence.

Multicenter evaluation of mechanical thrombectomy for distal medium vessel occlusions with National Institute of Health Stroke Scale Scores ≥ 6 and ≤ 6.

BACKGROUND: While mechanical thrombectomy is considered standard of care for large vessel occlusions, scientific evidence to support treatment for distal and medium vessel occlusions remains scarce. PURPOSE: To evaluate feasibility, safety, and outcomes in patients with low National Institute of Health Stroke Scale scores undergoing mechanical thrombectomy for treatment of distal medium vessel occlusions. MATERIALS AND METHODS: Retrospective data review and analysis of prospectively maintained databases at 41 academic centers in North America, Asia, and Europe between January 2017 and January 2022. Characteristics and outcomes were compared between groups with low stroke scale score (≤ 6) versus and higher stroke scale scores (> 6). Propensity score matching using the optimal pair matching method and 1:1 ratio was performed. RESULTS: Data were collected on a total of 1068 patients. After propensity score matching, there were a total of 676 patients included in the final analysis, with 338 patients in each group. High successful reperfusion rates were seen in both groups, 90.2% in ≤ 6 and 88.7% in the > 6 stroke scale groups. The frequency of excellent and good functional outcome was seen more common in low versus higher stroke scale score patients (64.5% and 81.1% versus 39.3% and 58.6%, respectively). The 90-day mortality rate observed in the ≤ 6 stroke scale group was 5.3% versus 13.3% in the > 6 stroke scale group. CONCLUSION: Mechanical thrombectomy in distal and medium vessel occlusions, specifically in patients with low stroke scale scores is feasible, though it may not necessarily improve outcomes over IVT.