Faculty Bibliography

BackgroundThe Woven EndoBridge (WEB) device represents an innovative solution for cerebral aneurysm occlusion, particularly for challenging wide-neck bifurcation aneurysms. However, factors affecting sustained occlusion remain poorly understood. We utilized machine learning to attempt to identify predictors of favorable long-term outcomes following WEB treatment.MethodsIn this multicenter retrospective study, we collected patient demographics, aneurysm characteristics, procedural details, and clinical outcomes. The primary endpoint was improvement in occlusion status, defined as maintained Raymond-Roy Occlusion Classification (RROC) grade 1, or improvement from grade 2 to 1, or from grade 3 to either 2 or 1 on final angiographic follow up. The dataset was split into training (75%) and validation (25%) sets. The CatBoost algorithm was selected based on performance metrics, with Shapley Additive exPlanations (SHAP) values calculated to determine feature importance. Furthermore, a multivariable binomial logistic regression model was performed to validate machine learning findings.ResultsAmong 720 aneurysms from 36 hospitals, 84% showed improvement in occlusion at follow up. Both machine learning and multivariable logistic regression identified aneurysm height as the most consistent correlate of nonimprovement (odds ratio (OR) 0.90 per mm, p = 0.022). In the CatBoost model, the highest-ranking features by SHAP included aneurysm height, patient age, treatment acuity, ACom location, WEB-SLS device, bifurcation anatomy, aneurysm multiplicity, baseline modified Rankin Scale, access route, and partial thrombosis.ConclusionsMachine-learning and regression analyses identified consistent predictors of occlusion improvement after WEB treatment, with aneurysm height most strongly linked to nonimprovement. These insights may guide patient selection and follow up. Findings require cautious interpretation and external validation in larger cohorts.

Spinal dural arteriovenous fistulas (dAVFs) at the craniocervical junction are rare vascular lesions that can cause progressive myelopathy and paralysis. This video presents a 40-year-old male with a left C1 spinal dAVF, who experienced unsteadiness, dizziness, leg weakness, and intermittent facial numbness. Given the lesion's symptomatology, the patient underwent a C1 laminectomy and midline suboccipital craniectomy for definitive obliteration. The authors describe key surgical techniques for fistula exposure and obliteration, with intraoperative angiographic confirmation. Long-term follow-up confirmed complete persistent occlusion on angiography and resolution of his symptoms. This case highlights surgical strategies for managing dAVFs at the craniocervical level. The video can be found here: https://stream.cadmore.media/r10.3171/2025.7.FOCVID2573.

BackgroundDuring mechanical thrombectomy for large-vessel occlusions, a ledge effect makes navigating the aspiration catheters (ACs) to the occlusion difficult. New large-bore macrowires minimize this while ensuring flexibility and navigational control. We evaluated the technical feasibility of delivering large-bore ACs to posterior circulation occlusions.MethodsThis retrospective multicenter study evaluated patients treated for posterior circulation strokes with adjunct-free macrowire-only direct aspiration first-pass technique (MO-ADAPT) using 0.024- and 0.035-in macrowires between October 2022 and December 2024. Primary outcomes included successful catheter delivery, successful MO-ADAPT (i.e. adjunct-free catheter delivery and successful clot aspiration), and first-pass reperfusion (i.e. modified thrombolysis in cerebral infarction (mTICI) score ≥ 2b after one MO-ADAPT pass).ResultsAmong 42 included patients (mean age 68.3 ± 15.4 years), adjunct-free delivery of ACs to the occlusion using macrowires only was successful in 95.2%. An MO-ADAPT primary approach achieved successful reperfusion in 81.0%, with first-pass reperfusion in 54.8%. Among patients with successful AC delivery, the aspiration success rate was 85.0%. Final mTICI scores of 3, 2c, and 2b after all procedures were seen in 78.6%, 14.3%, and 4.8%, respectively, regardless of thrombectomy method. No vascular complications were observed, and postprocedural intracranial hemorrhage and distal emboli occurred in 2.4% each. A favorable clinical outcome at 90 days was observed in 33.3% of cases. Multivariable analysis showed that underlying intracranial atherosclerotic disease was a negative predictor of both MO-ADAPT success and first-pass reperfusion; no factors predicted AC delivery success.ConclusionIn this retrospective series, MO-ADAPT appeared to be technically feasible for treating posterior circulation strokes, with promising procedural results and a low complication rate. Observed failures were mainly associated with underlying intracranial atherosclerotic disease requiring stent retriever-assisted mechanical thrombectomy. Given the limited sample size and study design, further studies, ideally with larger cohorts and comparative designs, are necessary to clarify the relative safety, efficacy, and cost effectiveness of MO-ADAPT.

RATIONALE/BACKGROUND:Whether syngo DynaCT Sine Spin non-contrast flat detector CT (FDCT) imaging is sufficient to rule out intracranial hemorrhage in suspected acute stroke patients is unknown. AIM/OBJECTIVE:To determine if syngo DynaCT Sine Spin non-contrast FDCT imaging is non-inferior to conventional multidetector CT (MDCT) imaging for the detection and exclusion of intracranial hemorrhages in suspected acute stroke patients. SAMPLE SIZE/METHODS:To enroll 252 participants in three buckets (126 ischemic stroke patients, 126 hemorrhagic stroke patients (including 14 patients with an isolated infratentorial hemorrhage). METHODS AND DESIGN/METHODS:A multicenter, international, prospective, cross-sectional, endpoint assessor blinded, non-inferiority trial. OUTCOMES/RESULTS:The primary outcome is the occurrence of an intracranial hemorrhage (yes versus no). This will be used to calculate the sensitivity and specificity of FDCT imaging for the detection of intracranial hemorrhages. All FDCT images will be rated by six independent raters in a blinded imaging core-lab. The rating of the MDCT images will be deemed as ground-truth. FDCT imaging will be deemed non-inferior if the lower bound of the 95%-Confidence Interval of the sensitivity and specificity is above 95%. DISCUSSION/CONCLUSIONS:This trial will inform physicians whether syngo DynaCT Sine Spin non-contrast FDCT imaging can reliably exclude intracranial hemorrhages in patients with suspected acute stroke. TRIAL REGISTRATION/BACKGROUND:ClinicalTrials.gov NCT05458908.

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.

Tethered postoperative drains are not uncommon complications that often require open removal in the operating room, which can increase risks of surgical site infection as well as length of hospitalization. We present a novel method of tethered drain removal through guidewire electrification. A retained deep drain following a posterior cervical laminectomy and fusion was identified after failed manual removal. Under fluoroscopic guidance, the retaining suture was indirectly identified through the obstruction of an inserted guidewire, through which monopolar cautery was applied, breaking the suture and allowing drain removal. The original incision did not need to be re-opened. While further investigation is necessary for validation, this technique shows great promise as an alternative to open removal.