William J. Ares

Introduction: THUNDER (Acute Ischemic Stroke Study With the Penumbra System Including Thunderbolt Aspiration Tubing) was the first study to evaluate the safety and effectiveness of a proprietary computer assisted vacuum thrombectomy (CAVT) system including modulated aspiration (Penumbra System with Thunderbolt; Penumbra, California, USA) in patients with emergent large vessel occlusion (ELVO). Methods: THUNDER was a single arm, prospective, multicenter study with core laboratory adjudication and oversight by a Clinical Events Committee and Data Safety Monitoring Board. The primary endpoint was post-Thunderbolt successful revascularization (modified Treatment in Cerebral Infarction (mTICI) 2b–3). Secondary endpoints included first pass mTICI 2b–3, post-Thunderbolt mTICI 2c–3, time to revascularization, symptomatic intracranial hemorrhages (sICH), device/procedure related serious adverse events (SAEs) within 24 hours, 90- day modified Rankin Score (mRS) 0–2, and all cause mortality. Results: 216 patients were enrolled across 29 US centers (mean age 64.8 years, 45.4% women, median National Institutes of Health Stroke Scale score 15.0). The predefined performance goal was met, with post-Thunderbolt mTICI 2b–3 revascularization achieved in 87.5% (95% CI 82.3% to 91.6%; P<0.001). First pass mTICI 2b–3 was 64.8%. Post-Thunderbolt mTICI 2c–3 was 70.4%. Median time to revascularization was 20 min. Post-procedure, 83.0% of visualized clots were characterized as ingested. At 90 days, mRS 0–2 was 55.4%. Device/procedure related SAEs occurred in 2.8%, sICH in 0.9%, and the rate of all cause mortality at 90 days was 11.7%. Conclusions: The Thunderbolt system was safe and effective for the treatment of ELVO, achieving high revascularization and clot ingestion rates, short procedure times, and low complication rates. The first pass effect rate was numerically higher than those previously reported for large bore catheters and approximated those of ultra bore/super large bore devices. Trial registration: ClinicalTrials.gov NCT05437055

Infarcts within the anterior cerebral artery (ACA) territory are uncommon, representing only 3-5% of all ischemic strokes. Infarcts within this area may closely mimic middle cerebral artery (MCA) syndromes due to overlapping clinical presentations such as contralateral hemiparesis and language impairment, leading to diagnosis uncertainty and delays in recognition of ACA involvement. Accurate and prompt identification of the correct clinical syndrome and vascular territories is essential for guiding timely reperfusion therapy. In this report, we present a 73-year-old right-handed male presenting with non-fluent aphasia and dense right-sided hemiparesis in the setting of mechanical rescue thrombectomy. This case illustrates the diagnostic challenges of atypical stroke presentations involving the ACA territory and highlights the precise clinical-radiographic correlation in identifying the affected vascular territory.

Background: During 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. Methods: This 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). Results: Among 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. Conclusion: In 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.

Background: Radiolucent head immobilization (RHI) devices have recently been introduced to the neurovascular space for the purpose of procedural efficiency and safety. However, limited data exists to support its efficacy. In this study, we assessed the potential benefits of RHI. We hypothesized that RHI use is associated with improved procedural efficiency without loss of angiographic image quality or increase in radiation exposure. Methods: A single-institution single-physician retrospective cohort study of patients who underwent cerebral digital subtraction angiography (DSA) or middle meningeal artery embolization (MMAE) under conscious sedation over a 1-year period was conducted. Comparative analyses of fluoroscopy time, image quality, and radiation dosage were performed. Results: Significantly shorter fluoroscopy times were observed for patients with RHI undergoing DSA ( p < 0.05) and bilateral MMAE ( p < 0.05). There was no significant difference in fluoroscopy time for patients undergoing a unilateral MMAE. No difference was found in total radiation dose between patients with RHI compared to patients without RHI. A blinded image quality comparison found no differences in image quality or presence of artifact upon review of DSA images. Conclusion: Use of RHI devices was associated with significantly lower fluoroscopy times for DSA and bilateral MMAE without sacrificing image quality. RHI may prove beneficial for decreasing procedural times, particularly during longer, conscious sedation procedures.

BACKGROUND AND OBJECTIVES: Middle meningeal artery embolization (MMAE) is a safe and efficacious adjunct to surgical evacuation for symptomatic chronic subdural hematoma (cSDH). We evaluated the concomitant performance of MMAE with surgical evacuation in a single anesthetic session rather than a staged approach. METHODS: In this retrospective, multicenter cohort study, patients with cSDH who underwent MMAE and surgical evacuation during 1 anesthetic session from January 2020 through August 2024 were included. The primary endpoints were feasibility (technical success), safety (complication and mortality rates), and efficacy (radiographic improvement and modified Rankin Scale score ≤2). RESULTS: Among 157 patients (median age 74 years), 66% had unilateral cSDH and 34% had bilateral disease. Technical success was achieved in 153 patients (97.4%), with no major intraprocedural failures. The overall complication rate was 10.8%, including intraprocedural complications (ie, vessel injuries, cardiac arrest) in 4 patients (2.5%) and periprocedural adverse events in 13 patients (8.3%), including seizures, hemorrhages, respiratory failure, ischemic events, infections, and recurrent hematomas. The overall mortality rate was 12.7% (6 [3.8%] early postoperative deaths, 13 [8.3%] late unrelated deaths). Radiographic improvement was observed in 91.7% of patients, with 63.1% achieving ≥50% reduction in hematoma thickness at last available follow-up. At median follow-up of 54 days, 99/118 (83.9%) patients achieved or maintained functional independence (modified Rankin Scale ≤2). CONCLUSION: Single-session MMAE with concomitant surgical evacuation proved feasible and safe. Radiographic and clinical outcomes were favorable, without higher complication rates compared with staged approaches. Future prospective studies should clarify the long-term benefits, assess the impact on resource use and cost-minimization, and determine ideal patient-selection criteria for this integrated treatment strategy.

Background: Larger “macrowires” may facilitate microcatheter-free delivery of large-bore aspiration catheters (ACs) for intracranial endovascular mechanical thrombectomy. We examined the safety and efficacy of the Aristotle Colossus Guidewire for this use. Methods: In this retrospective analysis of prospective data from 12 institutions, we identified anterior circulation endovascular mechanical thrombectomy cases involving the Aristotle Colossus guidewire over a 12-month period. The primary efficacy endpoint was successful delivery of the AC to the site without the use of adjunct devices. Multivariable logistic regression was performed with clinically relevant covariables. Results: In 122 patients (median age 74 years (interquartile range (IQR) 63–82)), most intracranial occlusions were in the M1 segment of the middle cerebral artery (95/122, 78.0%). The primary endpoint of microcatheter-free AC delivery was met in 87.7% (107/122) of patients; 93/122 (76.2%) patients underwent microcatheter-free delivery with successful reperfusion via contact aspiration (modified thrombolysis in cerebral infarction grade ≥ 2B). The median number of passes was 1 (IQR 1–2). Multivariable regression demonstrated that severe internal carotid artery tortuosity or cervical loop presence (odds ratio (OR): 0.09, 95% confidence interval (CI): 0.01–0.54, p = 0.01) and presence of intracranial atherosclerotic disease (OR: 0.15, 95% CI: 0.03–0.83, p = 0.03) were significantly associated with lower odds of successful AC delivery over the guidewire. Intraprocedural vasospasm occurred in 4.9% (6/122) of cases; there were no reports of vessel dissection or perforation. Conclusions: We demonstrate the favorable performance of the Aristotle Colossus guidewire for anterior circulation ischemic stroke intervention. The macrowire appears to safely facilitate navigation of the neurovasculature by large-bore ACs without the need for microcatheter and/or stentriever.

Background Flow-diverter stents (FDS) have become the standard of care for a wide range of intracranial aneurysms, but their efficacy/safety in the context of recurrent/recanalized aneurysms following stent-assisted coiling (SAC) is not well established. We evaluate the outcomes of FDS retreatment in a large multicenter cohort. Methods We retrospectively analyzed data from 118 patients across 22 institutions who underwent FDS retreatment for recurrent/persistent aneurysms after SAC (2008–22). The primary outcome was angiographic occlusion status at last follow-up, categorized as complete (100%), near-complete (90–99%), or incomplete (Results A total of 118 patients (median age 57, 74.6% female) with median follow-up of 15.3 months were identified. Complete occlusion was achieved in 62.5% and near-complete occlusion in 25%. FDS deployment within the pre-existing stent was successful in 98.3% of cases. Major complications occurred in 3.4% of cases, including postoperative aneurysmal rupture with resultant mortality (1.6%) and thromboembolic events with long-term disability (1.6%). Favorable clinical outcomes (mRS 0–2) were observed in 95.1% of patients. Wider aneurysm neck diameter was a significant predictor of incomplete occlusion (adjusted OR (aOR) 1.23 per mm, P=0.044), with male sex trending towards association with non-occlusion (aOR 3.2, P=0.07), while baseline hypertension was associated with complete occlusion (aOR 0.32, P=0.048). Conclusions FDS treatment for recurrent/residual aneurysms after SAC represents a viable treatment option for these challenging cases with acceptable safety and reasonable occlusion rates, although lower than de novo FDS occlusion rates.

Background Middle meningeal artery embolization (MMAE) is a safe and effective treatment for chronic subdural hematoma (cSDH); however, the appropriate level of postoperative care is unknown. Objective To evaluate whether elective MMAE for cSDH could be safely performed in an outpatient setting. Methods This was a multicenter, retrospective study of patients with cSDH who underwent elective MMAE. Patients were categorized as either inpatient (admitted for ≥1 night of hospitalization after MMAE) or outpatient (discharged on the same day of MMAE). Patient demographics, radiological data, procedural details, and follow-up data were collected. The primary endpoint was periprocedural complications, and secondary outcomes included emergency department (ED) visits or unplanned readmission within 24 hours, 1–7 days, and 8–30 days after MMAE. Results Elective MMAE procedures were carried out in 190 patients, of which 45.3% (n=86) were outpatient procedures and 54.7% (n=104) inpatient. There were 7 (3.7%) periprocedural complications (one outpatient, six inpatient; P=0.12). Five patients presented to the ED and were readmitted within 24 hours of MMAE (three outpatient, two inpatient). Six patients presented to the ED 1–7 days after MMAE (three outpatient, three inpatient); three were subsequently admitted (one outpatient and two inpatient). Nine patients presented to the ED 8–30 days after MMAE (two outpatient and seven inpatient); three were subsequently readmitted (all inpatient). No elective outpatient MMAE resulted in a readmission attributable to the procedure within the examined time frame. Conclusion Elective MMAE can be safely performed as an outpatient procedure without increased risk of postprocedural adverse events in most eligible patients with cSDH.