Background: Collateral circulation influences clinical outcomes in patients with acute ischemic stroke due to anterior circulation large-vessel occlusion (LVO). While both arterial and venous collateral assessments on single-phase computed tomography angiography (CTA) have prognostic value, they have traditionally been evaluated independently.
Purpose: We developed the CTA Collateral Impairment Score (CCIS), a composite measure incorporating arterial (Tan) and venous (Cortical Venous Opacification Score (COVES)) scores, and investigated its association with 90-day functional outcomes.
Background And Purpose: Prolonged venous transit (PVT) on time-to-maximum (Tmax) perfusion maps has been associated with worse outcomes in patients with acute ischemic stroke due to anterior circulation large-vessel occlusion (AIS-LVO). The qualitative nature of PVT assessment introduces potential variability, and its reproducibility has not been systematically evaluated.
Materials And Methods: In a retrospective study of patients with confirmed AIS-LVO, 2 board-certified neuroradiologists independently reviewed pretreatment Tmax maps to assess PVT in the posterior superior sagittal sinus and torcula.
Medium vessel occlusion (MeVO) contributes significantly to acute ischemic stroke (AIS). The hypoperfusion intensity ratio (HIR), reflecting collateral circulation via the ratio of Tmax >10s to Tmax >6s volumes, predicts infarct progression in large-vessel occlusions but is unstudied in MeVOs. In this multicenter, multinational retrospective study, we evaluated consecutive patients with MeVO who underwent mechanical thrombectomy with or without intravenous thrombolysis.
View Article and Find Full Text PDFBackground: Magnetic resonance angiography (MRA) is a commonly used non-invasive imaging modality for the follow-up of treated intracranial aneurysms. The 3-category Montreal classification system is widely used to evaluate treatment outcomes, including aneurysms treated with Woven EndoBridge (WEB) devices or coils. This study aimed to assess the reliability and clinical implications of the Montreal scale for aneurysms imaged with MRA.
View Article and Find Full Text PDFBackground: This single-center case series evaluates the effects on arterial diameter, perfusion imaging, and safety of intra-arterial (IA) nimodipine administration for CV following aSAH.
Methods: In this prospective single-center observational study (SAVEBRAIN PWI; NCT05276934), 14 patients with CV refractory to medical treatment were treated with IA nimodipine. We assessed changes in vessel diameter and perfusion parameters pre- and post-treatment.
ObjectiveMechanical thrombectomy (MT) is well-established for the treatment of acute ischemic stroke (AIS) from large vessel occlusion (LVO), with growing data supporting the expansion to distal and medium vessel occlusions (DMVO). Despite successful recanalization in DMVO, certain patients still experience poor long-term clinical outcomes, prompting our study to comprehensively explore pre-MT factors influencing outcome despite excellent recanalization (final modified Thrombolysis in Cerebral Infarction [mTICI] score ≥2c).MethodsWe retrospectively examined data from patients who consecutively underwent MT for a primary middle cerebral artery (MCA) DMVO across 37 centers in North America, Asia, and Europe.
View Article and Find Full Text PDFArterial inflow restoration and collateral status have been significantly correlated with functional outcomes in AIS-LVO patients undergoing mechanical thrombectomy (MT). CT perfusion imaging biomarkers, including prolonged venous transit (PVT), cerebral blood volume (CBV) index, and hypoperfusion intensity ratio (HIR), have emerged as reliable pretreatment adjunct parameters of comprehensive flow assessment. However, their absolute and comparative effectiveness in improving prognostic prediction remains unclear when used in conjunction with clinical and arterial inflow parameters.
View Article and Find Full Text PDFObjective: Mechanical thrombectomy (MT) is well established for large-vessel occlusion (LVO) strokes, but its safety in distal and medium-vessel occlusions (DMVOs) requires further investigation. This study analyzed the relationship between procedural approaches, petechial hemorrhage (PetH), and clinical outcomes in DMVO thrombectomy, with particular attention to technical considerations and the complex interplay between tissue injury and hemorrhagic complications.
Methods: A retrospective cohort study was conducted on DMVO stroke patients treated with MT at 37 stroke centers worldwide from 2016 to 2024.
Neuroradiology
July 2025
Purpose: Treating small-caliber vessel aneurysms with flow diverters poses challenges due to narrow luminal diameters and tortuous vasculature, which complicate the navigation and deployment of conventional devices using standard microcatheters. The Silk Vista Baby (SVB, Balt, Montmorency, France) flow diverter was developed to treat intracranial aneurysms located in smaller vessels or more distal segments and is compatible with 0.017″ microcatheters.
View Article and Find Full Text PDFBackgroundIsolated posterior cerebral artery (PCA) occlusions, which account for 5% of ischemic strokes, significantly impact patient quality of life due to effects on the thalamus and visual cortex. Current guidelines for acute treatment and the prognostic utility of perfusion imaging in PCA strokes remain limited and underexplored.MethodsWe conducted a retrospective analysis of 21 patients with isolated PCA occlusions from January 2017 to March 2023 at two comprehensive medical institutions.
View Article and Find Full Text PDFBackgroundEndovascular therapy (EVT) for stroke due to distal or medium vessel occlusion (DMVO) is safe. Due to the distinct anatomical characteristics of DMVOs, further evaluation of EVT is crucial to determine which devices may yield better outcomes.MethodsA retrospective analysis of adults with DMVO treated in 37 centers (11 countries) was queried.
View Article and Find Full Text PDFBackground: The Woven EndoBridge (WEB) device is a prevalent treatment for intracranial aneurysms. While many studies have assessed the obliteration rate post-WEB embolization, few have focused on long-term outcomes in partially thrombosed aneurysms.
Objective: To assess whether partially thrombosed aneurysms are at higher risk of recurrence or retreatment following WEB embolization compared with non-thrombosed aneurysms.
Background: Collateral status plays a crucial role in outcomes after acute ischemic stroke due to large vessel occlusion. Tissue-level collaterals and venous outflow are key components following mechanical thrombectomy. This study evaluates the predictive performance of prolonged venous transit (PVT), cerebral blood volume index, and hypoperfusion intensity ratio in determining 90-day functional outcomes.
View Article and Find Full Text PDFBackground And Purpose: Venous outflow (VO) impairment predicts unfavorable outcomes in patients with acute ischemic stroke caused by large vessel occlusion (AIS-LVO). Prolonged venous transit (PVT), a visual qualitative VO marker on CT perfusion (CTP) time to maximum (Tmax) maps, has been associated with 90-day mortality despite successful reperfusion. This study investigates the association between PVT and modified Rankin Scale (mRS) score at discharge among AIS-LVO patients who have undergone successful reperfusion.
View Article and Find Full Text PDFWhile the Woven EndoBridge (WEB) device has transformed the treatment of wide-neck intracranial aneurysms, incomplete occlusion remains a significant challenge requiring better understanding of contributing factors. A retrospective analysis was conducted on multicenter data from patients who underwent WEB device treatment for intracranial aneurysms between January 2011 and December 2022. Using machine learning models, Cox regression, and time-stratified analyses, we evaluated factors associated with persistent incomplete occlusion, defined as non-improving Raymond-Roy Occlusion Classification grade 2 or 3 at final follow-up.
View Article and Find Full Text PDFJ Neurointerv Surg
March 2025
Background: Mechanical thrombectomy (MT) is established as an effective treatment for large vessel occlusion strokes, but its efficacy and safety for medium vessel occlusions (MeVOs) remain less clear. This study examines the impact of periprocedural embolization to a new vascular territory (ENT) on clinical outcomes in patients with MeVO stroke treated with MT.
Methods: A multicenter, retrospective analysis was conducted using the MAD-MT (Multicenter Analysis of primary Distal medium vessel occlusions: effect of Mechanical Thrombectomy) registry, including 2122 patients with MeVO stroke w-ho underwent MT between September 2017 and July 2023.
The Woven EndoBridge (WEB) device is FDA-approved for the treatment of bifurcation aneurysms. Despite its wide popularity, it has been under scrutiny for its association with potential aneurysm recanalization and retreatment due to device shape modification. This study aims to analyze the shape modification rate of WEB devices and identify factors associated with this phenomenon, as well as its correlation with aneurysm retreatment.
View Article and Find Full Text PDFBackground: Acute ischaemic stroke (AIS) is a leading cause of mortality and disability globally, with volume contracted state (VCS), as indicated by an elevated blood urea nitrogen to creatinine (BUN/Cr) ratio, potentially influencing outcomes. This study investigates the association between VCS and clinical outcomes in patients with AIS due to large vessel occlusion (LVO).
Methods: A retrospective cohort study was conducted involving 298 patients with LVO-AIS from two comprehensive stroke centres.
Objective: Tobacco smoking is among the factors known to significantly augment the risk of untreated intracranial aneurysm (IA) growth and rupture. Smoking appears to have a variable effect on different endovascular treatment modalities. The impact of smoking on the safety, efficacy, and outcomes of Woven EndoBridge (WEB) device use for wide-neck IAs has not been evaluated.
View Article and Find Full Text PDFJ Neurointerv Surg
January 2025
Background: Current randomized controlled trials are investigating the efficacy and safety of mechanical thrombectomy (MT) in patients with medium vessel occlusion (MeVO) stroke. Whether best medical management (MM) is more efficient than unsuccessful vessel recanalization during MT remains unknown.
Methods: This was a retrospective cohort study using data from 37 academic centers across North America, Asia, and Europe between September 2017 and July 2021.
Background And Purpose: Prolonged length of stay (LOS) following a stroke is associated with unfavorable clinical outcomes. Factors predicting LOS in medium vessel occlusion (MeVO), impacting up to 40% of acute ischemic stroke (AIS) cases, remain underexplored. This study aims to investigate the predictors of LOS in AIS-MeVO.
View Article and Find Full Text PDFJ Neurointerv Surg
January 2025
The cerebral blood volume index (CBV index) is a perfusion-based marker of collateral status. Several real-world data analyses from observational stroke cohorts have established relationships between this parameter and a range of favorable and unfavorable stroke outcomes. In this review, an overview is provided of the CBV index, within the context of thrombectomy-treated large vessel and medium vessel occlusion ischemic strokes.
View Article and Find Full Text PDFIntroduction: Mechanical thrombectomy (MT) efficacy in medium vessel occlusion (MeVO) stroke, particularly in patients with low Alberta Stroke Program Early Computed Tomography Score (ASPECTS), remains less explored.
Methods: This retrospective study analyzed data from 443 AIS patients treated with MT for MeVO and low ASPECTS (4-7) at 37 centers across North America, Asia, and Europe, from September 2017 to July 2021. Patients were categorized into ASPECTS of 4-5 and 6-7.