Faculty Bibliography

BACKGROUND:Recent studies have suggested that favorable venous outflow (VO) may be a promising imaging biomarker to predict clinical outcomes following reperfusion therapy in patients with acute ischemic stroke caused by large vessel occlusion (AIS-LVO). METHODS:A comprehensive literature search was conducted in PubMed, Scopus, WOS, and Cochrane to identify studies that evaluated VO profiles, assessed using the Cortical Vein Opacification Score (COVES). The risk ratio (RR) and 95% confidence interval (CI) for the outcomes, including functional independence, assessed by modified rankin scale at 90 days (mRS 0-2), hemorrhagic infarction, parenchymal hematoma, 90-day mortality, intracranial hemorrhage (ICH), and symptomatic ICH (sICH), were calculated and analyzed using the 'meta' package in R version 4.4.1. RESULTS:A total of six studies encompassing 2249 patients were included. Patients with favorable VO had a higher likelihood of achieving functional independence at 90 days (RR = 2.15; 95% CI: 1.35, 3.42; p = 0.01) and a lower incidence of 90-day mortality (RR = 0.39; 95% CI: 0.30, 0.51; p < 0.01), parenchymal hematoma (RR = 0.36; 95% CI: 0.27, 0.47; p < 0.01). Furthermore, sICH was less frequent in patients with favorable VO (RR = 0.39; 95% CI: 0.17, 0.89; p = 0.03). However, hemorrhagic infarction and any ICH did not differ significantly between the two groups (p-values: 0.06 and 0.32, respectively). CONCLUSION/CONCLUSIONS:VO is a promising imaging biomarker for predicting outcomes in patients with AIS-LVO following reperfusion therapy. Prospective clinical trials are warranted to investigate the predictive value of VO, assessed on multiphasic computed tomography angiography (CTA), as a prognostic marker in this patient population.

BACKGROUND AND IMPORTANCE/BACKGROUND:Marfan syndrome's association with intracranial aneurysms, though controversial, poses unique challenges for surgical intervention because of the inherent vascular fragility. Open surgical approaches carry considerable risk. Endovascular flow diversion with the Pipeline embolization device (PED) offers a less invasive alternative, and adjunctive coiling can decrease occlusion time for complex aneurysms. We report the first combined use of PED and coiling to treat a Marfan-associated intracranial aneurysm, detailing our operative approach and reviewing the literature. CLINICAL PRESENTATION/METHODS:mutation was incidentally found to have an unruptured paraophthalmic aneurysm during stroke workup. Diagnostic angiography revealed an irregular superior hypophyseal aneurysm along with tortuous and irregular internal carotid arteries suggesting previous dissections. The aneurysm was successfully treated with a PED and adjunctive coil embolization. The patient was discharged on aspirin and clopidogrel. Six-month follow-up angiography confirmed aneurysm occlusion. Although there was no residual or recurrent aneurysm at 2-year follow-up, imaging revealed 2 de novo intracranial aneurysms. The patient remains asymptomatic and under observation. CONCLUSION/CONCLUSIONS:mutations and cerebrovascular pathology.

Medium vessel occlusions represent a substantial proportion of patients with acute ischemic stroke. Recently presented randomized controlled trials, ESCAPE-MeVO (Endovascular Treatment to Improve Outcomes for Medium Vessel Occlusions), DISTAL (Endovascular Therapy Plus Best Medical Treatment [BMT] Versus BMT Alone for Medium Distal Vessel Occlusion Stroke), and DISCOUNT (Evaluation of Mechanical Thrombectomy in Acute Ischemic Stroke Related to a Distal Arterial Occlusion), did not demonstrate a clinical benefit of endovascular thrombectomy in distal and medium vessel occlusions, potentially generating uncertainty about optimal treatment strategies for medium vessel occlusions. Specifically, these results may lead clinicians to hesitate in performing endovascular thrombectomy for M2 occlusions, despite prior evidence indicating benefit in this subgroup. In this review, we critically examine current literature, focusing on anatomic and functional definitions of M2 segments, and highlight the significant heterogeneity in their classification. We place a particular emphasis on proximal as well as dominant M2 branches and the existing evidence, including observational studies, meta-analyses, and prior randomized trials. Additionally, we discuss methodological limitations and patient-selection biases of recent neutral trials, which may warrant caution in the broad application of their findings. Lastly, we propose recommendations for future research, emphasizing the need for refined patient-selection criteria to better identify subgroups most likely to benefit from endovascular thrombectomy, improved classification systems for M2 occlusions, and the exploration of adjunctive and alternative therapies.

BACKGROUND:Osteogenesis imperfecta (OI) is a connective tissue disorder characterized by fragile bones and vascular fragility, increasing the risk of vessel dissection and potentially complicating endovascular intervention. The authors present the first case of cranial bypass in a patient with OI. OBSERVATIONS/METHODS:A 38-year-old male with OI type I presented with a symptomatic left internal carotid artery (ICA) occlusive dissection managed with endovascular revascularization and stenting. Follow-up surveillance imaging identified an incidental right ICA dissection, also treated with stenting. Four years later, the patient experienced new right hemispheric symptoms. He was found to have progressive right ICA dissection on best medical management. Following an unsuccessful restenting attempt, he underwent a successful double-barrel superficial temporal artery-to-middle cerebral artery (STA-MCA) bypass to restore cerebral perfusion with no perioperative complications. Six-month follow-up DSA confirmed a patent bypass with robust flow, and the patient remained asymptomatic 1 year postoperatively. LESSONS/CONCLUSIONS:STA-MCA bypass can serve as a viable and effective revascularization option in patients with OI, whose disease predisposes them to vascular dissection. In these high-risk patients, cranial bypass is a safe method for effective flow augmentation to hypoperfused brain regions when endovascular interventions fail. https://thejns.org/doi/10.3171/CASE25378.

BackgroundData on off-label use of flow diverter for ruptured distal anterior cerebral artery aneurysms (rDACAAs) are limited. The purpose of the present study is to evaluate the efficacy and safety of flow diversion for rDACAAs in a large multicenter cohort.MethodsA retrospective observational study on consecutive patients who were treated with flow diversion for rDACAAs at 8 centers in 4 countries was performed. Primary outcome was the occlusion rate of the target aneurysm at the last radiological follow-up. Secondary outcomes included good clinical outcome, retreatment, technical success, procedure-related complications, radiological outcome of the covered branches and mortality rate.ResultsA total of 21 patients with 21 rDACAAs were treated between January 2017 and December 2024. Thirteen patients were women (61.9%) and the median age was 54 years (IQR 46-66). The most common etiology was saccular (71.4%), followed by dissecting (23.8%) and mycotic (4.8%). In all patients a single stent was successful deployed. Median imaging follow-up was 9 (7-12) months. At last follow-up adequate occlusion was 95.2%. Symptomatic thromboembolic or hemorrhagic complications occurred in 9.5% of patients. Seventeen patients (81%) had good clinical outcome (mRS 0-2) with mortality rate of 9.5%. In-stent stenosis occurred in one case that was conservatively managed without major concerns.ConclusionsFlow diversion is feasible as a potential treatment strategy for acutely ruptured aneurysms arising from distal anterior cerebral artery. Flow diverter may represent a valid option whenever other treatments are considered challenging or high risk.

Definitive endoluminal reconstruction, widely known as flow diversion, revolutionized treatment of brain aneurysms. A range of targets, by location, size, etiology, and acuity, can be cured with an excellent risk/benefit profile. Requirement for effective antiplatelet state is balanced with superior treatment durability. Implant and delivery system technology continue to evolve. Some aneurysm types/locations remain undertreated. Maximizing efficacy while minimizing risks requires deep understanding of flow diversion principles, pathologic anatomy, endoluminal implants, delivery systems, and clinical management.

This article looks at the current state of aneurysm risk modeling, exploring the limitations of linear measurement. It reviews articles using Food and Drug Administration (FDA)-approved artificial intelligence-driven volumetric measurement tools both for evaluating potential aneurysm growth in patients being managed conservatively as well as in assessing morphologic change prerupture and postrupture. The challenges of defining the aneurysm boundary are explored, and a novel definition of aneurysm/parent artery interface is proposed.

Although the concept of treating cerebral aneurysms by filling the sac from the inside (endosaccular) started many years ago first with detachable balloons and then coils, the use of a single metallic resheathable device acting as a flow disruptor is a much more recent innovation. The most studied device among these is certainly the WEB, which became part of standard clinical practice for treatment of wide-neck bifurcation aneurysms. This study reviews the most important features of the WEB device with a short summary of the most important literature. A small section at the end reviews also other endosaccular devices.

Imaging follow-up is an established component of intracranial aneurysm management that allows ongoing assessment of rupture risk and timely intervention to maintain protection from bleeding. Yet the frequency, duration, and imaging modality for follow-up vary widely. This review outlines contemporary imaging techniques and practice for follow-up of treated and untreated aneurysms, highlighting existing knowledge gaps and technical limitations that limit standardization. Updated evidence on the expected evolution and long-term outcome of common treatment strategies is presented to guide accurate reporting of radiological outcome after treatment and considerations regarding follow-up regimen.

PURPOSE/OBJECTIVE: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. We present the largest multicenter analysis to date evaluating the outcomes of SVB use in unruptured distal anterior cerebral artery (DACA) aneurysms. METHODS:Retrospective data from 20 centers were reviewed for patients with unruptured DACA aneurysms treated with the SVB. Demographic information, clinical presentation, radiographic characteristics, complications, and outcomes were recorded. RESULTS:Seventy-nine patients (79 DACA aneurysms) were treated between January 2018 and December 2022; 59 were female (74.7%), and the median age was 61 years (IQR 53-67). Most aneurysms were saccular (89.9%), and 65.8% involved a branch. The median parent vessel diameter was 1.9 mm (IQR 1.7-2.1). A single stent was implanted in 97.5% of cases; 2.5% required two stents. The median imaging follow-up duration was 12 months (IQR 9.5-24). At the last follow-up, 76% of aneurysms showed complete or near-complete occlusion (O'Kelly-Marotta scale C or D, Raymond-Roy 1 or 2). Overall, thromboembolic or hemorrhagic complications occurred in 14% of patients, with two cases being symptomatic. The mortality rate was 0%, and the retreatment rate was 1.3%. CONCLUSION/CONCLUSIONS:In this multicenter series, the SVB flow diverter represented a valuable treatment option for distal anterior cerebral artery (DACA) aneurysms.