Isaac Josh Abecassis

BACKGROUND AND OBJECTIVES: Tiny or very small unruptured intracranial aneurysms (≤3 mm) carry a very low estimated rupture risk, yet many are electively treated. Although factors influencing procedural risks have the potential to guide treatment selection, they remain poorly characterized in this population. METHODS: A retrospective cohort study was conducted using prospectively collected data from the multicenter Stroke Thrombectomy and Aneurysm Registry, including patients treated for unruptured aneurysms between 2013 and 2025. Tiny aneurysms were defined as ≤3 mm. Primary outcomes were intraprocedural and postprocedural complications. Propensity score matching and multivariable logistic regression were performed. RESULTS: Among 5107 treated aneurysms, 783 (15.3%) were tiny. Patients with tiny aneurysms were younger, more often female, and had higher rates of vascular risk factors, prior subarachnoid hemorrhage, or family history of aneurysms ( P < .05). Intraoperative complications (5.2% vs 5.1%, P = .91), postprocedural complications (8.4% vs 8.7%, P = .83), in-hospital mortality, and long-term outcomes were comparable with small (3-5 mm) aneurysms. On multivariable analysis, anterior communicating artery (odds ratio [OR] 4.92; 95% CI, 1.34-18.1; P = .016) and posterior communicating artery locations (OR 4.08; 95% CI, 1.40-11.9; P = .010), as well as stent-assisted coiling (OR 3.98; 95% CI, 1.33-11.9; P = .013) predicted intraoperative complications, while favorable preadmission functional status (modified Rankin Scale 0-1; OR 0.40; 95% CI, 0.21-0.76) predicted lower postprocedural complication risk. CONCLUSION: Treatment of tiny unruptured aneurysms remains common despite very low rupture risk. Procedural risks are low and comparable with slightly larger aneurysms. Treatment decisions should integrate both rupture risk and procedural safety, with anterior communicating artery or posterior communicating artery locations and unfavorable baseline functional status representing higher-risk features. When indicated, stent-assisted coiling was independently associated with higher intraoperative complication risk relative to clipping in this cohort.

Background: Randomized trials have shown equivocal outcomes between a direct aspiration as first-pass technique (ADAPT) and stent retriever (SR) stroke thrombectomy, yet whether specific patient subgroups benefit differentially from one technique over the other remains unknown. Methods: In this retrospective multicenter cohort study, patients with large vessel occlusion were included, and those who underwent ADAPT versus SR first-pass thrombectomy (either as standalone or combined with aspiration) were compared. The primary outcome was a composite of first-pass effect (FPE, modified Thrombolysis In Cerebral Infarction (mTICI) 2c or better with one attempt) with no symptomatic intracranial hemorrhage (sICH). A causal forest model was used to estimate the conditional average treatment effect (CATE) for each patient, with larger CATEs indicating that ADAPT is expected to be more advantageous. Patients were stratified by CATEs, and outcomes were compared between treatment groups. Results: Among 6700 included patients, ADAPT (n=3695, 55%) was associated with a higher rate of FPE with no sICH (39.9% vs 26.9%; adjusted OR (aOR) 2.07, 95% CI 1.77 to 2.41, P<0.001). The causal forest identified significant treatment effect heterogeneity (interaction P<0.001), where ADAPT was more advantageous in more recent years and among patients with M1 occlusions presenting in earlier time windows. Low-CATE patients showed no statistically significant difference between techniques (aOR 0.91, 95% CI 0.57 to 1.45, P=0.70), while medium- and high-CATE patients demonstrated progressively larger ADAPT advantages (aOR 2.06, 95% CI 1.67 to 2.55, and aOR 2.99, 95% CI 2.24 to 3.98, respectively, both P<0.001). Conclusions: ADAPT may be superior to SR for a majority of patients, particularly in recent years, and among patients with M1 occlusions presenting in earlier time windows.

BACKGROUND: Hemorrhagic risk in dural arteriovenous fistulas (dAVFs) is largely determined by venous anatomy, but the contribution of systemic cardiovascular factors and their medical therapy remains poorly defined. This study examined associations between cardiovascular risk factors and antithrombotic use and hemorrhagic presentation, angiographic obliteration, and early functional outcomes after treatment. METHODS: We analyzed 1350 adults with intracranial dAVFs from the international Consortium for Dural Arteriovenous Fistula Outcomes Research registry, which retrospectively accrued cases across 14 centers in 4 countries between 1990 and 2017. Demographics, cardiovascular comorbidities, antithrombotic use, angioarchitectural features, treatment strategies, and follow-up outcomes were collected from prospectively maintained databases. Primary end points were hemorrhagic presentation, angiographic obliteration, and 90-day functional status after treatment. Univariable and multivariable logistic regressions were performed with model-specific adjustments. RESULTS: Hemorrhage occurred in 375 patients (27.8%) and was most strongly associated with high-grade dAVF classification and male sex; antithrombotic therapy was associated with lower odds of hemorrhagic presentation. Other cardiovascular risk factors showed no independent relationship with bleeding. Angiographic obliteration was achieved in 621 of 845 patients (73.5%). Hemorrhagic onset, high dAVF grade, and surgical treatment were independently associated with angiographic obliteration, whereas smoking and embolization demonstrated only nonsignificant trends after adjustment. At 90 days, 934 patients (88.9%) were functionally independent. Baseline modified Rankin Scale score was the strongest factor associated with 90-day functional outcome, while neither cardiovascular comorbidities nor treatment modality independently influenced functional status. CONCLUSIONS: In this large multicenter dAVF cohort, hemorrhagic presentation was most strongly associated with venous angioarchitecture. Male sex and antithrombotic therapy were also independently associated with hemorrhagic presentation. Angiographic obliteration was common, particularly among surgically treated lesions, and 90-day functional outcome was most strongly associated with baseline functional status.

Introduction Delivering large-bore aspiration catheters through tortuous anatomy remains challenging during mechanical thrombectomy (MT). The Carrier delivery-assist catheter (DAC) was designed to facilitate aspiration catheter navigation, but multicenter data remain limited. We evaluated the efficiency and safety of the Carrier DAC. Methods We performed a multicenter retrospective study of prospectively collected data from patients undergoing MT at 15 U.S. Comprehensive Stroke Centers (September 2024?September 2025). Co-primary endpoints were puncture-to-clot engagement time and first-pass effect (FPE; eTICI 2c?3). A pre-specified single-center analysis compared upfront contact aspiration using the Carrier DAC versus standard 0.021? microcatheter techniques with identical aspiration catheter sizes. Results The multicenter cohort included 211 Carrier-assisted MTs. Median aspiration catheter inner diameter was 0.071?, with super-bore catheters used in 5.7%. Median puncture-to-clot time was 12 minutes, and FPE was achieved in 50.7%. Median puncture-to-reperfusion time was 20 minutes, and mFPE occurred in 74.4%. Parenchymal hematoma and subarachnoid hemorrhage occurred in 11.8% and 6.6%, respectively. Cavernous tortuosity did not affect primary endpoints. The single-center analysis included 242 patients. Carrier use was associated with shorter puncture-to-clot times and numerically higher FPE rates without increased hemorrhagic complications. Conclusions The Carrier DAC enables efficient navigation of large-bore aspiration catheters and may reduce procedural time while maintaining procedural safety. Prospective studies are warranted.

BACKGROUND AND OBJECTIVES: Traumatic cerebral venous sinus injury (tCVSI) is a rare but serious complication of traumatic brain injury. Although similar radiographically to spontaneous cerebral venous sinus thrombosis (CVST), tCVSI treatment approaches have not been fully investigated. We characterized complications, clinical outcomes, and recanalization in tCVSI and evaluated treatment approaches. METHODS: In this retrospective review of patients with radiographically confirmed tCVSI across 3 Level 1 trauma centers from 2018 to 2024, we collected patient characteristics, injury patterns, treatment modalities, complications, clinical outcomes, and recanalization data. Primary outcomes were favorable recovery (extended Glasgow Outcome Scale score ≥5) and 30-day mortality. Multivariate regression identified independent predictors of outcomes and recanalization. RESULTS: Among 11 300 patients screened, 254 (2.2%) had tCVSI. Antiplatelet (AP) and anticoagulation (AC) therapy were used in 32% and 19% of patients, respectively. Hemorrhagic complications occurred in 31% of patients treated with AC and 10% receiving AP. Favorable outcomes were achieved in 73.9% of patients, and 30-day mortality was 12.6%. On multivariate analysis, AP (odds ratio [OR] 6.5, 95% CI 2.1-20.0) and AC (OR 4.7, 95% CI 1.3-17.7) therapies were both associated with better outcomes. AP therapy was independently associated with lower 30-day mortality (OR 0.2, 95% CI 0.06-0.66). At the follow-up, 39.9% of patients had complete recanalization of the involved sinus, 17.5% had partial recanalization, and 42.7% were unchanged. Recanalization status on repeat imaging did not correlate with clinical outcomes. CONCLUSION: This multicenter series demonstrates treatment response in patients after tCVSI and describes differences in natural history compared with spontaneous CVST. Both antithrombotic regimens were associated with favorable outcomes, and AP therapy was independently associated with lower mortality, suggesting a potential role in tCVSI management. Recanalization status at follow-up appeared unrelated to clinical outcomes, supporting the need for unique therapeutic approaches for tCVSI compared with spontaneous CVST, particularly in the acute management period.

BACKGROUND: Intracranial mycotic aneurysms are rare, representing only 0.7%–5.4% of all intracranial aneurysms, and typically arise from septic emboli secondary to infective endocarditis. Large-vessel occlusion due to a septic embolus is exceedingly uncommon and carries high morbidity. OBSERVATIONS: A 29-year-old man with methicillin-resistant Staphylococcus aureus endocarditis and intravenous drug use presented with intracerebral and subarachnoid hemorrhage. CT angiography revealed a left parieto-occipital hematoma with midline shift. An emergency craniotomy for hematoma evacuation exposed a ruptured distal middle cerebral artery (MCA) mycotic aneurysm, which was clipped, and pathological analysis confirmed abscess formation within the aneurysm wall. Despite antibiotic therapy, a new distal MCA aneurysm developed within an abscess cavity. Cerebral angiography later demonstrated M1 occlusion requiring mechanical thrombectomy, achieving partial reperfusion consistent with Thrombolysis in Cerebral Infarction grade 2a. The persistent abscess and aneurysm required Onyx embolization and abscess drainage in a hybrid operating room. LESSONS: Sequential mycotic aneurysms with concurrent large-vessel occlusion and abscess formation represent a rare and aggressive manifestation of septic emboli. Successful management depends on coordinated microsurgical clipping, endovascular embolization, thrombectomy, and abscess evacuation. Early recognition of evolving vascular pathology and combined surgical-endovascular approaches improve outcomes in infective mycotic aneurysm–related cerebrovascular disease. https://thejns.org/doi/10.3171/CASE25902

Intracranial mycotic aneurysms are rare, representing only 0.7%-5.4% of all intracranial aneurysms, and typically arise from septic emboli secondary to infective endocarditis. Large-vessel occlusion due to a septic embolus is exceedingly uncommon and carries high morbidity. A 29-year-old man with methicillin-resistant Staphylococcus aureus endocarditis and intravenous drug use presented with intracerebral and subarachnoid hemorrhage. CT angiography revealed a left parieto-occipital hematoma with midline shift. An emergency craniotomy for hematoma evacuation exposed a ruptured distal middle cerebral artery (MCA) mycotic aneurysm, which was clipped, and pathological analysis confirmed abscess formation within the aneurysm wall. Despite antibiotic therapy, a new distal MCA aneurysm developed within an abscess cavity. Cerebral angiography later demonstrated M1 occlusion requiring mechanical thrombectomy, achieving partial reperfusion consistent with Thrombolysis in Cerebral Infarction grade 2a. The persistent abscess and aneurysm required Onyx embolization and abscess drainage in a hybrid operating room. Sequential mycotic aneurysms with concurrent large-vessel occlusion and abscess formation represent a rare and aggressive manifestation of septic emboli. Successful management depends on coordinated microsurgical clipping, endovascular embolization, thrombectomy, and abscess evacuation. Early recognition of evolving vascular pathology and combined surgical-endovascular approaches improve outcomes in infective mycotic aneurysm-related cerebrovascular disease. https://thejns.org/doi/10.3171/CASE25902.