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.

Glb1 knockout mouse model shares natural history with type II GM1 gangliosidosis patients.

GM1 gangliosidosis is a rare lysosomal storage disorder affecting multiple organ systems, primarily the central nervous system, and is caused by functional deficiency of ß-galactosidase (GLB1). Using CRISPR/Cas9 genome editing, we generated a mouse model to evaluate characteristics of the disease in comparison to GM1 gangliosidosis patients. Our Glb1-/- mice contain small deletions in exons 2 and 6, producing a null allele. Longevity is approximately 50 weeks and studies demonstrated that female Glb1-/- mice die six weeks earlier than male Glb1-/- mice. Gait analyses showed progressive abnormalities including abnormal foot placement, decreased stride length and increased stance width, comparable with what is observed in type II GM1 gangliosidosis patients. Furthermore, Glb1-/- mice show loss of motor skills by 20 weeks assessed by adhesive dot, hanging wire, and inverted grid tests, and deterioration of motor coordination by 32 weeks of age when evaluated by rotarod testing. Brain MRI showed progressive cerebellar atrophy in Glb1-/- mice as seen in some patients. In addition, Glb1-/- mice also show significantly increased levels of a novel pentasaccharide biomarker in urine and plasma which we also observed in GM1 gangliosidosis patients. Glb1-/- mice also exhibit accumulation of glycosphingolipids in the brain with increases in GM1 and GA1 beginning by 8 weeks. Surprisingly, despite being a null variant, this Glb1-/- mouse most closely models the less severe type II disease and will guide the development of new therapies for patients with the disorder.

Acute ischaemic stroke associated with SARS-CoV-2 infection in North America.

BACKGROUND: To analyse the clinical characteristics of COVID-19 with acute ischaemic stroke (AIS) and identify factors predicting functional outcome. METHODS: Multicentre retrospective cohort study of COVID-19 patients with AIS who presented to 30 stroke centres in the USA and Canada between 14 March and 30 August 2020. The primary endpoint was poor functional outcome, defined as a modified Rankin Scale (mRS) of 5 or 6 at discharge. Secondary endpoints include favourable outcome (mRS ≤2) and mortality at discharge, ordinal mRS (shift analysis), symptomatic intracranial haemorrhage (sICH) and occurrence of in-hospital complications. RESULTS: A total of 216 COVID-19 patients with AIS were included. 68.1% (147/216) were older than 60 years, while 31.9% (69/216) were younger. Median [IQR] National Institutes of Health Stroke Scale (NIHSS) at presentation was 12.5 (15.8), and 44.2% (87/197) presented with large vessel occlusion (LVO). Approximately 51.3% (98/191) of the patients had poor outcomes with an observed mortality rate of 39.1% (81/207). Age >60 years (aOR: 5.11, 95% CI 2.08 to 12.56, p<0.001), diabetes mellitus (aOR: 2.66, 95% CI 1.16 to 6.09, p=0.021), higher NIHSS at admission (aOR: 1.08, 95% CI 1.02 to 1.14, p=0.006), LVO (aOR: 2.45, 95% CI 1.04 to 5.78, p=0.042), and higher NLR level (aOR: 1.06, 95% CI 1.01 to 1.11, p=0.028) were significantly associated with poor functional outcome. CONCLUSION: There is relationship between COVID-19-associated AIS and severe disability or death. We identified several factors which predict worse outcomes, and these outcomes were more frequent compared to global averages. We found that elevated neutrophil-to-lymphocyte ratio, rather than D-Dimer, predicted both morbidity and mortality.

Treatment of elastase-induced intracranial aneurysms in New Zealand white rabbits by use of a novel neurovascular embolization stent device.

INTRODUCTION: This study aims to test a novel balloon expandable stent covered with a polytetrafluoroethylene membrane (neurovascular embolization cover (NEC), NFocus Neuromedical, Palo Alto, California) regarding angiographic and histologic aneurysm occlusion. Radiopacity, stent placement, navigation, flexibility, and intimal proliferation were also evaluated. METHODS: Eight aneurysms were induced in New Zealand white rabbits. Digital subtraction angiography (DSA) was performed directly after stent placement and after 5 and 10 min. Four and 8 weeks after stent placement, an intra-arterial DSA control was performed. The animals were then sacrificed and the aneurysms histologically evaluated. RESULTS: The radiopaque markers were clearly visible. Although all the stents were easily navigated into the subclavian artery, the limited flexibility of the stent resulted in straightening of the vessel in four cases. As a result, exact stent placement was achieved and acutely confirmed in only two cases. However, at sacrifice, angiographic and histologic occlusion was noted at follow-up in five aneurysms. CONCLUSION: In tortuous anatomy, the relative stiffness of the stent makes exact stent placement challenging. This may have been exacerbated by the movement of the vessels due to proximity to the heart in this model. Future studies should evaluate whether existing residual flow into an aneurysm lumen might lead to embolization without any additional treatment. Anticoagulation remains a very important part of aneurysm treatment with stents. The trend toward aneurysm occlusion by excluding it from the blood circulation seems a promising method in future endovascular therapy. The NEC device shows good potential.

Dual Antiplatelet Non-Responder: Resistance to Clopidogrel and Ticagrelor.

Background: Dual antiplatelet therapy is often required for neurointerventional procedures, especially when a stent or flow diverter is placed in the cervical and intracranial vessels. Patients are usually started on aspirin and clopidogrel given the simplicity of the once daily regimen with reasonable cost. Unfortunately, about a third of patients do not show the desired antiplatelet response to clopidogrel and another agent needs to be introduced. Ticagrelor is a potent antiplatelet medication that has a favorable pharmacological profile and has emerged as a reliable alternative to clopidogrel in recent years. Despite ticagrelor non-responders being rare, they do exist, and identification of these patients is important. Results: A 74-year-old female was incidentally found to harbor a right posterior communicating aneurysm which was successfully treated electively with stent-assisted coiling. Platelet inhibition testing revealed non-responsiveness to Clopidogrel. Ticagrelor was initiated but the patient's platelet reactivity unit remained in the normal range. Management algorithms to maximize a patient's ticagrelor response by facilitating enteral absorption were applied but no platelet inhibition was achieved. The patient was eventually identified as a true ticagrelor non-responder. Conclusion: Resistance to antiplatelet medication can result in devastating complications with permanent neurological deficits. Ticagrelor non-responders are rare but do exist. Platelet inhibition testing should be part of the preprocedural workup for neurointerventions.

I saw the swirl sign: Acute extravasation of blood within a hematoma.

The swirl sign is a finding on non-contrast computed tomography (CT) scans that represents an acute extravasation of blood into a hematoma filled with clotted blood. In it, a "swirl" of active bleeding within a body of acutely clotted blood is noted as a hypodense accumulation within a hyperdense fluid collection. Here, we describe a case in which a 35-year-old female presents unresponsive with a Glasgow Coma Scale score of 3 and is ultimately found to have a large frontal intraparenchymal hematoma with intraventricular extension and an area of low attenuation within the hyperattenuating fluid collection on CT, otherwise known as the swirl sign. This radiographic sign has been associated with hematoma expansion, worse clinical outcomes as measured by the Glasgow Outcome Scale, and higher mortality rates. As such, all patients suspected to have intracranial bleeds should have CT imaging done as soon as possible. When the swirl sign is identified on CT, providers are clued in to the risk of clinical deterioration and the urgent need for surgical evaluation.

I saw the 'puff of smoke' sign before it vanished into thin air.

Moyamoya is characterized as a non-atherosclerotic and non-inflammatory vasculopathy that leads to progressive stenosis of the intracranial internal carotid arteries as well as the Circle of Willis. While it can be idiopathic (Moyamoya disease) or associated with another condition (Moyamoya syndrome), there is a characteristic 'puff of smoke' sign that can be appreciated on cerebral angiography.

First United States multicenter experience with the new-generation FRED X surface-modified flow diversion stent: feasibility, safety, and short-term efficacy.

OBJECTIVE: Flow diversion created a paradigm shift in the treatment of intracranial aneurysms. The new flow redirection endoluminal device with X technology (FRED X) is the latest update of the recent Food and Drug Administration-approved FRED. The FRED X is engineered to reduce material thrombogenicity and enhance vessel healing. In this study, the authors aimed to evaluate the feasibility and early safety and efficacy of the new FRED X. METHODS: The authors retrospectively collected and analyzed data from patients who had undergone flow diversion with the new FRED X at four tertiary cerebrovascular centers in the United States from February 2022 through July 2022. RESULTS: Forty-four patients with 45 aneurysms treated using 46 devices comprised the overall study cohort and were divided into two groups: 39 patients with unruptured aneurysms and 5 patients with ruptured aneurysms. The mean patient age was 57.7 ± 9.1 years, and most patients were female (84%). Ninety-one percent of the aneurysms were saccular, with the majority (93%) located in the anterior circulation, specifically the posterior communicating (27%) and carotid ophthalmic (27%) territories. The mean maximum aneurysm diameter was 5.6 ± 4.6 mm, and 20% of the lesions had been previously treated. The mean procedure time was 61.6 minutes, with a mean cumulative fluoroscopy time of 24.6 minutes. Additionally, 7% of the lesions received adjunct treatment. Stent placement was successful in 100% of cases, achieving good wall apposition and complete neck coverage. Further, immediate aneurysm contrast stasis > 90% was observed in 61% of cases. Symptomatic postoperative complications occurred in 3 patients in the unruptured cohort and 1 patient in the ruptured cohort. All patients in the study were discharged on dual antiplatelet regimens with a modified Rankin Scale score of 0. At 6 months after treatment, 89% of cases had adequate occlusion, with < 6% of cases having asymptomatic in-stent stenosis. All patients had excellent functional outcomes. CONCLUSIONS: FRED X for the treatment of an intracranial aneurysm is technically feasible alone or in conjunction with intrasaccular embolization. In addition, the study results showed very promising early safety and efficacy. Follow-up studies should establish the long-term safety and efficacy profiles of this new stent.

Multicenter early United States feasibility study and periprocedural safety of LVIS EVO for the treatment of unruptured intracranial aneurysms.

BACKGROUND: Stent development has focused recently on low-profile, self-expandable stents compatible with 0.0165 inch microcatheters. The LVIS EVO is the second-generation version of the Low-Profile Visualized Intraluminal Support (LVIS) with improved visibility and resheathability. The LVIS EVO underwent a limited premarket release (PMR) in December 2023. This study aims to report the early safety and feasibility experience with the LVIS EVO stent for the treatment of intracranial aneurysms in the United States (US). METHODS: This was a multicenter, retrospective, observational study evaluating patients who underwent treatment of an intracranial aneurysm with an LVIS EVO stent after the limited PMR. All physicians who had placed an LVIS EVO stent were asked to input their cases after institutional review board approval was obtained. The data were then sent to a single center for analysis. Any patient aged 18 years or older who underwent treatment of an intracranial aneurysm with a LVIS EVO stent in the US was included from the initial PMR in December 2023 until April 2024. Patient age (or ≤90 years old), sex, preoperative modified Rankin Scale (mRS), aneurysm location, aneurysm measurements, and information about preoperative antiplatelet management were all collected. Data on periprocedural complications, 30-day mortality, discharge mRS, and length of stay were also collected. RESULTS: Some 53 patients with 55 aneurysms underwent treatment with the LVIS EVO stent at 15 institutions. All aneurysms were unruptured. The most common location was the anterior communicating artery (35%) followed by the middle cerebral artery bifurcation (31%). All patients were on dual antiplatelet therapy. The average aneurysm size was 5.2 mm with a neck size of 3.7 mm. The smallest distal parent vessel size was 1.2 mm and 36% of stents were deployed in distal parent vessels <2 mm. All (100%) cases had successful deployment and the stent was repositioned in 10% of cases. A single stent was utilized in 91% of cases. Coils were placed in 48 cases (87.2%) and a microcatheter was jailed in 98% of those cases. Immediate Raymond Roy (RR) Class I occlusion was obtained in 33%, Class II in 22%, Class IIIa in 37%, and Class IIIb in 8% of cases. There were no delayed thromboembolic or hemorrhagic complications. CONCLUSIONS: The LVIS EVO is a braided, self-expanding, retrievable stent with enhanced visibility and smaller cell size. The drawn filled tube (DFT) technology results in improved visibility of the stent, allowing for more controlled stent positioning and visualization of vessel wall apposition. All cases in our series had complete neck coverage and good wall apposition. There were no thromboembolic or hemorrhagic complications.

Safety and effectiveness assessment of the surpass evolve (SEASE): a post-market international multicenter study.

BACKGROUND: Flow diverters are the first-line treatment for specific intracranial aneurysms (iA). Surpass Evolve (SE) is a new-generation 64-wire flow diverter with a high braid angle. Current literature on the SE is limited. We aimed to report the first international real-world experience evaluating the safety and effectiveness of the SE. METHODS: The Safety and Effectiveness Assessment of the Surpass Evolve (SEASE) was a multicenter retrospective international post-marketing cohort study including consecutive patients treated with SE for iAs between 2020 and 2022. Demographic, clinical, and angiographic data were collected. Primary effectiveness was independent core lab adjudicated complete occlusion rates (Raymond-Roy Class 1) at last follow-up. Primary safety were major ischemic/hemorrhagic events and mortality. RESULTS: In total, 305 patients with 332 aneurysms underwent SE implantation. The patients had a median age of 59 [50-67] years, and 256 (83.9%) were female. The baseline modified Rankin scale score was 0-2 in 291 patients (96.7%). Most aneurysms were unruptured (285, 93.4%) and saccular (309, 93.1%). Previous treatment was present in 76 (22.9%) patients. The median aneurysm size was 5.1 [3.4-9.0] mm, and the median neck width was 3.6 [2.7-5.1] mm. Most aneurysms were in the internal carotid artery C6 ophthalmic segment (126, 38.0%), followed by the communicating segment (58, 17.5%). At median 10.2 [6.4-12.9] months follow-up, 233 (73.0%) aneurysms achieved complete occlusion. After adjusting for confounders, complete occlusion remained consistent. Major stroke and procedure-related mortality were reported in 6 (2%) and 2 (0.7%) cases, respectively. CONCLUSION: These results demonstrate that SE has a consistently high effectiveness and favorable safety for the treatment of iAs.

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.

Symptomatic intracerebral hemorrhage in proximal and distal medium middle cerebral artery occlusion patients treated with mechanical thrombectomy.

BACKGROUND: Acute ischemic stroke (AIS) caused by distal medium vessel occlusions (DMVOs) represents a significant proportion of overall stroke cases. While intravenous thrombolysis (IVT) has been a primary treatment, advancements in endovascular procedures have led to increased use of mechanical thrombectomy (MT) in DMVO stroke patients. However, symptomatic intracerebral hemorrhage (sICH) remains a critical complication of AIS, particularly after undergoing intervention. This study aims to identify factors associated with sICH in DMVO stroke patients undergoing MT. METHODS: This retrospective analysis utilized data from the Multicenter Analysis of Distal Medium Vessel Occlusions: Effect of Mechanical Thrombectomy (MAD-MT) registry, involving 37 centers across North America, Asia, and Europe. Middle cerebral artery (MCA) DMVO stroke patients were included. The primary outcome measured was sICH, as defined per the Heidelberg Bleeding Classification. Univariable and multivariable logistic regression were used to identify factors independently associated with sICH. RESULTS: Among 1708 DMVO stroke patients, 148 (8.7%) developed sICH. Factors associated with sICH in DMVO patients treated with MT included older age (adjusted odds ratio (aOR) 1.01, 95% confidence interval (95% CI) 1.00 to 1.03, P=0.048), distal occlusion site (M3, M4) compared with medium occlusions (M2) (aOR 1.71, 95% CI 1.07 to 2.74, P=0.026), prior use of antiplatelet drugs (aOR 2.06, 95% CI 1.41 to 2.99, P<0.001), lower Alberta Stroke Program Early CT Scores (ASPECTS) (aOR 0.75, 95% CI 0.66 to 0.84, P<0.001), higher preoperative blood glucose level (aOR 1.00, 95% CI 1.00 to 1.01, P=0.012), number of passes (aOR 1.27, 95% CI 1.15 to 1.39, P<0.001), and successful recanalization (Thrombolysis In Cerebral Infarction (TICI) 2b-3) (aOR 0.43, 95% CI 0.28 to 0.66, P<0.001). CONCLUSION: This study provides novel insight into factors associated with sICH in patients undergoing MT for DMVO, emphasizing the importance of age, distal occlusion site, prior use of antiplatelet drugs, lower ASPECTS, higher preoperative blood glucose level, and procedural factors such as the number of passes and successful recanalization. Pending confirmation, consideration of these factors may improve personalized treatment strategies.

Incidence and clinical outcomes of perforations during mechanical thrombectomy for medium vessel occlusion in acute ischemic stroke: A retrospective, multicenter, and multinational study.

BACKGROUND: Mechanical thrombectomy (MT) has revolutionized the treatment of acute ischemic stroke (AIS) due to large vessel occlusion (LVO), but its efficacy and safety in medium vessel occlusion (MeVO) remain less explored. This multicenter, retrospective study aims to investigate the incidence and clinical outcomes of vessel perforations (confirmed by extravasation during an angiographic series) during MT for AIS caused by MeVO. METHODS: Data were collected from 37 academic centers across North America, Asia, and Europe between September 2017 and July 2021. A total of 1373 AIS patients with MeVO underwent MT. Baseline characteristics, procedural details, and clinical outcomes were analyzed. RESULTS: The incidence of vessel perforation was 4.8% (66/1373). Notably, our analysis indicates variations in perforation rates across different arterial segments: 8.9% in M3 segments, 4.3% in M2 segments, and 8.3% in A2 segments (p = 0.612). Patients with perforation had significantly worse outcomes, with lower rates of favorable angiographic outcomes (TICI 2c-3: 23% vs 58.9%, p < 0.001; TICI 2b-3: 56.5% vs 88.3%, p < 0.001). Functional outcomes were also worse in the perforation group (mRS 0-1 at 3 months: 22.7% vs 36.6%, p = 0.031; mRS 0-2 at 3 months: 28.8% vs 53.9%, p < 0.001). Mortality was higher in the perforation group (30.3% vs 16.8%, p = 0.008). CONCLUSION: This study reveals that while the occurrence of vessel perforation in MT for AIS due to MeVO is relatively rare, it is associated with poor functional outcomes and higher mortality. The findings highlight the need for increased caution and specialized training in performing MT for MeVO. Further prospective research is required for risk mitigation strategies.

The Impact of Preprocedural Platelet Function Testing on Periprocedural Complication Rates Associated With Pipeline Flow Diversion: An International Multicenter Study.

BACKGROUND AND OBJECTIVES: Dual antiplatelet therapy (DAPT) is necessary to minimize the risk of periprocedural thromboembolic complications associated with aneurysm embolization using pipeline embolization device (PED). We aimed to assess the impact of platelet function testing (PFT) on reducing periprocedural thromboembolic complications associated with PED flow diversion in patients receiving aspirin and clopidogrel. METHODS: Patients with unruptured intracranial aneurysms requiring PED flow diversion were identified from 13 centers for retrospective evaluation. Clinical variables including the results of PFT before treatment, periprocedural DAPT regimen, and intracranial complications occurring within 72 h of embolization were identified. Complication rates were compared between PFT and non-PFT groups. Differences between groups were tested for statistical significance using the Wilcoxon rank sum, Fisher exact, or χ 2 tests. A P -value <.05 was statistically significant. RESULTS: 580 patients underwent PED embolization with 262 patients dichotomized to the PFT group and 318 patients to the non-PFT group. 13.7% of PFT group patients were clopidogrel nonresponders requiring changes in their pre-embolization DAPT regimen. Five percentage of PFT group [2.8%, 8.5%] patients experienced thromboembolic complications vs 1.6% of patients in the non-PFT group [0.6%, 3.8%] ( P = .019). Two (15.4%) PFT group patients with thromboembolic complications experienced permanent neurological disability vs 4 (80%) non-PFT group patients. 3.7% of PFT group patients [1.5%, 8.2%] and 3.5% [1.8%, 6.3%] of non-PFT group patients experienced hemorrhagic intracranial complications ( P > .9). CONCLUSION: Preprocedural PFT before PED treatment of intracranial aneurysms in patients premedicated with an aspirin and clopidogrel DAPT regimen may not be necessary to significantly reduce the risk of procedure-related intracranial complications.

Comparative Efficacy of Flow Diverter Devices in the Treatment of Carotid Sidewall Intracranial Aneurysms: a Retrospective, Multicenter Study.

BACKGROUND: The comparative efficacy and safety of first-generation flow diverters (FDs), Pipeline Embolization Device (PED) (Medtronic, Irvine, California), Silk (Balt Extrusion, Montmorency, France), Flow Re-direction Endoluminal Device (FRED) (Microvention, Tustin, California), and Surpass Streamline (Stryker Neurovascular, Fremont, California), is not directly established and largely inferred. PURPOSE: This study aimed to compare the efficacy of different FDs in treating sidewall ICA intracranial aneurysms. METHODS: We conducted a retrospective review of prospectively maintained databases from eighteen academic institutions from 2009-2016, comprising 444 patients treated with one of four devices for sidewall ICA aneurysms. Data on demographics, aneurysm characteristics, treatment outcomes, and complications were analyzed. Angiographic and clinical outcomes were assessed using various imaging modalities and modified Rankin Scale (mRS). Propensity score weighting was employed to balance confounding variables. The data analysis used Kaplan-Meier curves, logistic regression, and Cox proportional-hazards regression. RESULTS: While there were no significant differences in retreatment rates, functional outcomes (mRS 0-1), and thromboembolic complications between the four devices, the probability of achieving adequate occlusion at the last follow-up was highest in Surpass device (HR: 4.59; CI: 2.75-7.66, p < 0.001), followed by FRED (HR: 2.23; CI: 1.44-3.46, p < 0.001), PED (HR: 1.72; CI: 1.10-2.70, p = 0.018), and Silk (HR: 1.0 ref. standard). The only hemorrhagic complications were with Surpass (1%). CONCLUSION: All the first-generation devices achieved good clinical outcomes and retreatment rates in treating ICA sidewall aneurysms. Prospective studies are needed to explore the nuanced differences between these devices in the long term.

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.