Search

Background We report the largest multicenter experience to date of utilizing the Comaneci device for endovascular treatment of refractory intracranial vasospasm. Methods Consecutive patients undergoing Comaneci mechanical dilatation for vasospasm were extracted from prospectively maintained registries in 11 North American centers (2020-2022). Intra-arterial vasodilators (IAV) were allowed, with the Comaneci device utilized after absence of vessel dilation post-infusion. Pre-and postvasospasm treatment scores were recorded for each segment, with primary radiological outcome of score improvement post-treatment. Primary clinical outcome was safety/device-related complications, with secondary endpoints of functional outcomes at last follow-up. Results A total of 129 vessels in 40 patients (median age 52 years; 67.5% females) received mechanical dilation, 109 of which (84.5%) exhibited pre-treatment severe-tocritical vasospasm (ie, score 3/4). Aneurysmal subarachnoid hemorrhage was the most common etiology of vasospasm (85%), with 65% of procedures utilizing Comaneci-17 (92.5% of patients received IAV). The most treated segments were anterior cerebral artery (34.9%) and middle cerebral artery (31%). Significant vasospasm drop (pre-treatment score (3-4) to post-treatment (0-2)) was achieved in 89.9% of vessels (96.1% of vessels experienced ≥1-point drop in score post-treatment). There were no major procedural/ post-procedural device-related complications. Primary failure (ie, vessel unresponsive) was encountered in one vessel (1 patient) (1/129; 0.8%) while secondary failure (ie, recurrence in previously treated segment requiring retreatment in another procedure) occurred in 16 vessels (7 patients) (16/129; 12.4%), with median time-to-retreatment of 2 days. Favorable clinical outcome (modified Rankin Scale 0-2) was noted in 51.5% of patients (median follow-up 6 months). Conclusions The Comaneci device provides a complementary strategy for treatment of refractory vasospasm with reasonable efficacy/favorable safety. Future prospective trials are warranted. [ABSTRACT FROM AUTHOR]

Background The transcirculation approach (TCA) for stent-assisted coiling (SAC) of intracranial aneurysms may be useful for certain wide-neck bifurcation aneurysms as well as those with acute-angle efferent branches. Objective To describe a multicenter experience using the TCA for SAC. Methods A multicenter, retrospective study (2016-2020) of aneurysm treatment using SAC via the TCA. Angiographic outcome was scored using the Raymond Scale (adequate occlusion 1 and 2), and clinical outcome was scored using a modified Rankin Scale (good outcome 0-2) Results Twenty-nine patients with 29 aneurysms were included (62.1% female; average age 61; 89.7% unruptured; 13.8% previously treated; average dome size 6.4 mm; average neck 4.4 mm). Aneurysm locations included internal carotid artery-fetal posterior cerebral artery (n=4), internal carotid artery terminus (n=4), anterior communicating artery (n=8), vertebral artery-posterior inferior cerebellar artery (n=2), and basilar tip (n=11). The TCA used communicating arteries (93.1%; average 1.6 mm), intermediate catheters (51.7%), jailing technique (62.1%), and staged procedures (10.3%). The most common stent was the Neuroform Atlas (Stryker; 69%). Immediate adequate occlusion was obtained in 75.9%, and five patients with inadequate occlusion progressed to adequate occlusion at follow-up. One (3.4%) procedural complication occurred: a watershed stroke in the setting of baseline four-vessel extracranial disease. Two patients had a poor outcome unrelated to the TCA. The majority of patients (86.4%) had a good clinical outcome. One case of in-stent stenosis due to non-compliance with medication was seen, which resolved with medication resumption. Conclusions The TCA for SAC can be performed for a variety of aneurysms with a low complication rate and good clinical outcomes. [ABSTRACT FROM AUTHOR]

background Flow diversion is a common endovascular treatment for cerebral aneurysms, but studies comparing different types of flow diverters are scarce. Objective To perform a propensity score matched cohort study comparing the Pipeline Embolization Device (PED) and Flow Redirection Intraluminal Device (FRED) for posterior circulation aneurysms. Methods Consecutive aneurysms of the posterior circulation treated at 25 neurovascular centers with either PED or FRED were collected. Propensity score matching was used to control for age, duration of followup imaging, adjunctive coiling, and aneurysm location, size, and morphology; previously ruptured aneurysms were excluded. The two devices were compared for the following outcomes: procedural complications, aneurysm occlusion, and functional outcome. results A total of 375 aneurysms of the posterior circulation were treated in 369 patients. The PED was used in 285 (77.2%) and FRED in 84 (22.8%) procedures. Aneurysms treated with the PED were more commonly fusiform and larger than those treated with FRED. To account for these important differences, propensity score matching was performed resulting in 33 PED and FRED unruptured aneurysm pairs. No differences were found in occlusion status and neurologic thromboembolic or hemorrhagic complications between the two devices. The proportion of patients with favorable functional outcome was higher with FRED (100% vs 87.9%, p=0.04). Conclusion Comparative analysis of PED and FRED for the treatment of unruptured posterior circulation aneurysms did not identify significant differences in aneurysm occlusion or neurologic complications. Variations in functional outcomes warrant additional investigations. [ABSTRACT FROM AUTHOR]

Introduction symptomatic internal carotid artery occlusion (ICAO) can lead to neurologic decline, recurrent stroke, and mortality. Objective We sought to evaluate the safety and feasibility of endovascular revascularization for icaO without tandem intracranial large vessel occlusion (LVO). Design, setting, and participants This is a retrospective cohort analysis of all patients presenting to a single academic center with ischemic stroke and ipsilateral cervical ICAO from november 2003 through april 2016. Patients were excluded if pre-procedural angiography demonstrated tandem LVO or if patients were known to have chronic ICAO. Main outcome(s) and measure(s) study endpoints included discharge neurologic examination, postprocedural infarct burden, 3-month functional outcomes, and treatment durability. results a total of 107 patients with symptomatic angiographically-confirmed cervical icaO without tandem LVO were identified. Median admission nih stroke scale (NIHSS) score was 8 (IQR 11). Baseline radiographic stroke severity was assessed by asPecT score (median 9; IQR 2), perfusion mismatch (present in 93%), and clinical imaging mismatch (42%). Median time from symptom onset to treatment was 25 hours (IQR 61). successful revascularization was achieved in 92% of patients. at discharge, 83% had stable/ improved nihss score, while at 3 months 65% achieved independence (modified rankin scale score ≤2). The most common complication was distal embolization (22%) of which 16% required intra-arterial treatment. rate of significant restenosis (≥70%) was 15% at 1 year. Conclusions stenting in selected patients at risk of neurologic deterioration due to symptomatic icaO can be performed with high rates of technical success and good clinical outcomes. Because of significant periprocedural risks and high rates of restenosis, randomized studies are necessary to understand the benefit of this approach. [ABSTRACT FROM AUTHOR]

Background The pipeline embolization device (PED) is frequently used in the treatment of anterior circulation aneurysms, especially around the carotid siphon, with generally excellent results. However, treatment of posterior inferior cerebellar artery (PICA) aneurysms with flow diversion (FD) has not been specifically described or discussed. While there are reports of treating PICA aneurysms using placement of FD stents in the vertebral artery, there are no reports of treating these lesions by placement of flow diverting stents in the PICA vessel itself. Due to the unique anatomy and morphology of these aneurysms, it requires special attention. We assessed our multi-institutional experience treating these lesions, including the first reported cases of the PED placed within the PICA. Methods Institutional databases of neuroendovascular procedures were reviewed for cases of intracranial aneurysms treated with the PED. Patient and aneurysm data as well as angiographic imaging were reviewed for all cases of PICA aneurysms treated with the PED. PICA aneurysms were defined as aneurysms that involved the PICA. Vertebral aneurysms without disease in the PICA were excluded from the study. Results 10 PICA aneurysms were treated during the study period. These were classified based on their morphology and location into two main types and five total subtypes for consideration of treatment with flow diversion. All aneurysms were successfully treated, with 8/10 completely obliterated and 2 with a partial reduction in size. Three patients had the PED placed entirely in the PICA and no patient suffered from a medullary or cerebellar stroke. All PEDs were patent and all patients were independent at the last follow-up. Conclusions The PED may be used successfully to treat select aneurysms of the PICA. We present the first described cases of successful PED treatment of PICA aneurysms with direct placement of the PED in the PICA vessel itself. The proposed classification system aids in that selection. [ABSTRACT FROM AUTHOR]

Background Anterior choroidal artery (AChA) aneurysms represent a small subset of cerebral aneurysms. The Pipeline Embolization Device (PED) has been successfully applied to various aneurysms of the supraclinoid internal carotid artery (ICA). The treatment of these aneurysms requires special attention due to the eloquent territory supplied by the AChA. We report the largest and first dedicated series of flow diversion treatment of AChA aneurysms. Methods Four institutional neurointerventional databases were reviewed for cases of intracranial aneurysms treated with PED. Patient and aneurysm data as well as angiographic imaging were reviewed for all cases of AChA aneurysms treated with PED. AChA aneurysms were defined as aneurysms distal to the AChA and proximal to the ICA terminus, with or without the incorporation of the AChA. Results Eighteen AChA aneurysms were treated during the study period. All aneurysms were successfully treated with a mean follow-up of 19.1 months. The large majority of aneurysms (15/18, 83.3%) were completely obliterated. No patients suffered from intra- or post-procedural complications. A1 stenosis was a common occurrence, seen in 10 of 16 (62.5%) covered anterior cerebral arteries (ACAs), although all were asymptomatic. All AChAs remained patent at last follow-up. Conclusions The PED can be used successfully in AChA aneurysms with a good safety and efficacy profile. All AChAs remained patent. Collateral flow networks, especially for the ACA, affect long-term branch vessel patency. Treatment with PED for AChA aneurysms appears to be a reasonable option to consider and should be evaluated in a larger cohort. [ABSTRACT FROM AUTHOR]

Aim To describe procedural aspects and clinical outcomes in a consecutive series of patients in whom manual aspiration thrombectomy (MAT) was performed as the first treatment modality with other techniques used only in case MAT did not yield recanalization. Methods A retrospective review of a prospectively acquired acute stroke intervention database was performed. Primary MAT was carried out with a preference for the largest catheter considered to be trackable into the target occlusive lesion. The catheter was wedged into the thrombus followed by manual aspiration with a 20 ml syringe. Results 112 consecutive patients were evaluated. The median age was 66 years and the median NIH Stroke Scale score was 17. Occlusion locations included the M1 (62%), M2 (8%), internal carotid artery terminus (19%) and the vertebrobasilar artery (11%). Patients with anterior occlusions had tandem extracranial/intracranial occlusive lesions in 18.7% Median time from symptom onset to groin puncture was 267 min, and from groin puncture to recanalization was 70 min. Successful recanalization (defined as Thrombolysis in Cerebral Infarction (TICI) 2b/3) with primary MAT was 59% with a median of two passes. 41% of patients required the use of adjunctive therapy yielding an overall recanalization rate of TICI 2b/3 (86%) and TICI 3 (30.6%). Parenchymal hematoma of any type (PH1/PH2) was seen in 9.8% of patients, with symptomatic hemorrhage in 6%. Favorable outcomes (90-day modified Rankin Scale ≤2) were 46%. Mortality at 3 months was 31%. Primary MAT was associated with faster procedural times (mean 63 vs 97 min, p<0.0001) but not with higher rates of favorable outcomes. Conclusions Primary MAT is an alternative endovascular recanalization technique with reasonable first pass efficacy that will likely improve with technology and experience. [ABSTRACT FROM AUTHOR]

Background Large vessel occlusive disease portends a poor prognosis unless recanalization is rapidly achieved. Endovascular treatment is typically performed via a transfemoral approach, but catheterization of the occluded vessel can be problematic in cases of extensive vessel tortuosity. Methods A retrospective review of a prospectively maintained database identified 7 patients who underwent acute endovascular reperfusion therapy via transcervical approach. Results We identified 7 patients. Admission NIHSS ranged from 8-27 and recanalization occurred between 7-49 min of carotid access. Prior to carotid access, 20-90 min were spent attempting target vessel catheterization via the transfemoral approach. All occlusions were in the left MCA. In 87.5% of patient, TICI2b/3 recanalization was achieved. Neck hematoma formation occurred in one case requiring elective intubation. At 2 months followup, all patients had survived with mRS 0-4 except for one patient who had a large infarct despite recanalization. Conclusions Transcervical access for acute ischemic stroke leads to rapid and high quality recanalization. Future studies will focus on improved hemostasis and early identification of patients who would benefit the most from direct carotid access for acute stroke. [ABSTRACT FROM AUTHOR]

Background and purpose Percutaneous transfemoral arterial procedures rely on a variety of vascular closure methods. We studied closure success and complications after using the Mynx vascular closure device in cerebral neurovascular procedures. Methods We prospectively analyzed patients undergoing diagnostic cerebral angiogram or neurointervention with arteriotomy closure using the Mynx device. Patient demographics and procedural factors were recorded. Statistical analyses compared groups and identified predictors of device failure and complication. Results A total of 766 patients, 59% women, mean age 55.5 years (SD 14.2), mean body mass index (BMI) 29.1 kg/m2 (SD 7.4), underwent 937 neurovascular procedures in a 10 month period. Device success was achieved in 92% of patients; lower BMI, higher number of antithrombotic medications, larger sheath size, and performance of a neurointerventional procedure predicted Mynx failure. Complications occurred in 2.45% of procedures, with older age, lower BMI, higher number of antithrombotic medicines used, higher international normalized ratio, lower platelet count, and Mynx device failure conferring an increased risk of complication. Conclusions The Mynx device is safe and effective for cerebral neurovascular procedures. However, specific patient populations may warrant particular attention and thorough consideration of risks and benefits prior to employing the Mynx device for femoral arteriotomy closure. [ABSTRACT FROM AUTHOR]

Background Infectious intracranial aneurysms (IIAs) are rare and potentially devastating. First-line management involves intravenous antibiotics, with surgical or endovascular management reserved for cases of failed medical treatment or aneurysmal rupture. Endovascular therapy has become the primary approach for treating these small, distally located aneurysms. Liquid embolic agents are well suited for use because of their ability to fill the aneurysm and parent vessel. We present our experience in treating these aneurysms via Onyx embolization and review the literature. Methods We retrospectively reviewed the endovascular treatment of IIAs at our institution from 2010 to 2012. Eight patients with 16 IIAs ranging in size from 1 to 16 mm underwent treatment. Seven of the patients initially presented after aneurysmal rupture. Onyx was pushed until the aneurysm and parent artery were filled. Confirmation of aneurysmal occlusion was made by repeat cerebral angiography. Results One symptomatic stroke occurred after embolization. Fourteen of the 16 aneurysms have been evaluated with follow-up angiography and remain occluded. Conclusions Treatment of IIAs using an endovascular approach with Onyx is safe and effective. [ABSTRACT FROM AUTHOR]

The complication rates of carotid artery stenting (CAS) vary from 3.0% to 4.4%, and most commonly include ischemic stroke, intracranial hemorrhage, or groin complications. We present the rare complication of a patient who underwent CAS for a symptomatic 90% left internal carotid artery stenosis and developed an expanding cervical hematoma after the procedure with imminent respiratory compromise. After intubation, an arteriogram revealed perforation of the external carotid artery trunk, proximal to the origin of the internal maxillary artery. The artery was subsequently embolized and the hematoma resolved without further intervention. We present a potential catastrophic complication and suggest potential causes and treatment options available. [ABSTRACT FROM AUTHOR]

The complication rates of carotid artery stenting (CAS) vary from 3.0% to 4.4%, and most commonly include ischemic stroke, intracranial hemorrhage, or groin complications. We present the rare complication of a patient who underwent CAS for a symptomatic 90% left internal carotid artery stenosis and developed an expanding cervical hematoma after the procedure with imminent respiratory compromise. After intubation, an arteriogram revealed perforation of the external carotid artery trunk, proximal to the origin of the internal maxillary artery. The artery was subsequently embolized and the hematoma resolved without further intervention. We present a potential catastrophic complication and suggest potential causes and treatment options available. [ABSTRACT FROM AUTHOR]

Background: Intracranial atherosclerotic disease (ICAD) is a leading cause of stroke, often refractory to aggressive medical therapy. Recent advancements in drug-eluting stents (DES) show promise for improved efficacy in intracranial applications relative to traditional ICAD treatments., Methods: We retrospectively collected all consecutive deployments of the Onyx Frontier [Medtronic, Santa Rosa, CA] stent in the setting of ICAD between August 2022 and August 2024 at six high-volume neuro-interventional centers across the US. Patients were included if their indication for stenting (eg, acute/recurrent stroke) was secondary to ICAD. Primary outcome was periprocedural stroke (<72 hours) and secondary outcomes included degree of pre- and post-stent vessel stenosis and National Institutes of Health Stroke Scale (NIHSS) scores at most recent follow-up. Secondary outcomes were assessed via paired t-tests., Results: Among 55 patients that met our inclusion criteria, the mean age was 62, mean presentation NIHSS was 10, and 40% were female. A total of 62 devices were used. Most common occlusion locations included the middle cerebral and internal carotid arteries. The periprocedural stroke rate was 10.9%, with a mortality rate of 1.8%. Mean vessel stenosis significantly decreased from 84.90% pre-stent to 2.00% post-stent (P<0.05). Mean NIHSS score improved from 10.37 preoperatively to 3.23 at follow-up (p<0.05). Procedural failure did not occur, however complications occurred in 16.4% of cases., Conclusion: Our findings suggest that stenting in this setting results in a lower periprocedural stroke rate than appreciated in historical trials such as SAMMPRIS and VISSIT. However, recent CASSISS and BASIS trials demonstrate far reduced periprocedural stroke rates in the context of submaximal angioplasty for ICAD. This, in conjunction with complication rate, suggest that the Onyx Frontier, while promising, may not offer a definitive solution to ICAD., Competing Interests: Competing interests: JKB has disclosed consulting fees from Cerenovus, Stryker, Q’Apel, Microvention, and the National Football League, related to work performed outside the submitted study. He has no other relationships, financial or otherwise, to declare.VMS has disclosed grants or contracts from Zeiss, Siemens, Medtronic, and Stryker, and consulting fees from Cerenovus, Stryker, Imperative Care, and the National Football League, related to work performed outside the submitted study. He has no other relationships, financial or otherwise, to declare.The remaining authors have no competing interests to declare., (© Author(s) (or their employer(s)) 2025. No commercial re-use. See rights and permissions. Published by BMJ Group.)

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., Competing Interests: Competing interests: CPK: Research grant support from Integra, Penumbra, Viz.AI, Siemens, Medtronic, Minnetronix, Longeviti, Irras, ICE Neurosystems, CVAID, Endostream, and Microtransponder; equity interest in Precision Recovery, Borealis, E8, Borvo, and Metis Innovative. Metis Innovative is an investment group that has coordinated investments in Synchron, Proprio, Fluid Biomed, Von Vascular, and Precision Recovery. JKB: Consulting for Stryker, Microvention, Cerenovus, Q’Apel, Balt and Siemens. RG: Consulting for Cerenovus, Stryker, Balt, Rapid Medical and Medtronic. MRL: Unrestricted educational grants from Medtronic and Stryker; equity interest in Proprio, Synchron, Hyperion Surgical, Stroke Diagnostics, Fluid Biomed, Apertur; consulting for Aeaean Advisers, Metis Innovative, Stereotaxis, Genomadix, AIDoc; data safety monitoring board of Arsenal Medical; editorial board of Journal of NeuroInterventional Surgery., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ Group.)

Background: With transradial access (TRA) being more progressively used in neuroendovascular procedures, we compared TRA with transfemoral access (TFA) in middle meningeal artery embolization (MMAE) for chronic subdural hematoma (cSDH)., Methods: Consecutive patients undergoing MMAE for cSDH at 14 North American centers (2018-23) were included. TRA and TFA groups were compared using propensity score matching (PSM) controlling for: age, sex, concurrent surgery, previous surgery, hematoma thickness and side, midline shift, and pretreatment antithrombotics. The primary outcome was access site and overall complications, and procedure duration; secondary endpoints were surgical rescue, radiographic improvement, and technical success and length of stay., Results: 872 patients (median age 73 years, 72.9% men) underwent 1070 MMAE procedures (54% TFA vs 46% TRA). Access site hematoma occurred in three TFA cases (0.5%; none required operative intervention) versus 0% in TRA (P=0.23), and radial-to-femoral conversion occurred in 1% of TRA cases. TRA was more used in right sided cSDH (58.4% vs 44.8%; P<0.001). Particle embolics were significantly higher in TFA while Onyx was higher in TRA (P<0.001). Following PSM, 150 matched pairs were generated. Particles were more utilized in the TFA group (53% vs 29.7%) and Onyx was more utilized in the TRA group (56.1% vs 31.5%) (P=0.001). Procedural duration was longer in the TRA group (median 68.5 min (IQR 43.1-95) vs 59 (42-84); P=0.038), and radiographic success was higher in the TFA group (87.3% vs 77.4%; P=0.036). No differences were noted in surgical rescue (8.4% vs 10.1%, P=0.35) or technical failures (2.4% vs 2%; P=0.67) between TFA and TRA. Sensitivity analysis in the standalone MMAE retained all associations but differences in procedural duration., Conclusions: In this study, TRA offered comparable outcomes to TFA in MMAE for cSDH in terms of access related and overall complications, technical feasibility, and functional outcomes. Procedural duration was slightly longer in the TRA group, and radiographic success was higher in the TFA group, with no differences in surgical rescue rates., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: A combination of intravenous (IVT) or intra-arterial (IAT) thrombolysis with mechanical thrombectomy (MT) for acute ischemic stroke due to large vessel occlusion (AIS-LVO) has been investigated. However, there is limited data on patients who receive both IVT and IAT compared with IVT alone before MT., Methods: STAR data from 2013 to 2023 was utilized. We performed propensity score matching between the two groups. The primary outcomes were symptomatic intracranial hemorrhage (sICH) and 90-day modified Rankin Scale (mRS) score 0-2. Secondary outcomes included successful recanalization (modified treatment in cerebral infarction (mTICI) ≥2B, ≥2C), early neurological improvement, any intracranial hemorrhage (ICH), and 90-day mortality., Results: A total of 2454 AIS-LVO patients were included. Propensity matching yielded 190 well-matched patients in each group. No significant differences were observed between the groups in either ICH or sICH (odds ratio (OR): 0.80, 95% confidence interval (CI) 0.51-1.24, P=0.37; OR: 0.60, 95% CI 0.29 to 1.24, P=0.21, respectively). Rates of successful recanalization and early neurological improvement (ENI) were significantly lower in MT+IVT + IAT. mRS 0-1 and mortality were not significantly different between the two groups. However, the MT+IVT + IAT group demonstrated superior rates of good functional outcomes (90-day mRS 0-1) compared with patients in the MT+IVT group who had mTICI ≤2B, (OR: 2.18, 95% CI 1.05 to 3.99, P=0.04)., Conclusion: The combined use of IAT and IVT thrombolysis in AIS-LVO patients undergoing MT is safe. Although the MT+IVT+ IAT group demonstrated lower rates of recanalization and early neurological improvement, long-term functional outcomes were favorable in this group suggesting a potential delayed benefit of IAT., Competing Interests: Competing interests: HM received a lecture fee from Daiichi-Sankyo and Stryker and consulting services fees from B Braun. ILM: speakers' honoraria from Pfizer and Bristol-Myers Squibb. RMS: research is supported by the NREF, Joe Niekro Foundation, Brain Aneurysm Foundation, Bee Foundation, Department of Health Biomedical Research Grant (21K02AWD-007000) and by National Institute of Health (R01NS111119-01A1) and (UL1TR002736, KL2TR002737) through the Miami Clinical and Translational Science Institute, from the National Center for Advancing Translational Sciences and the National Institute on Minority Health and Health Disparities. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the NIH. RMS has an unrestricted research grant from Medtronic and Balt and has consulting and teaching agreements with Penumbra, Abbott, Medtronic, Balt, InNeuroCo, Cerenovus, Naglreiter, Tonbridge, Von Medical, and Optimize Vascular. MNP: Grants from the Swiss National Science Foundation (SNF) for the DISTAL trial (33IC30198783) and TECNO trial (32003B204977), Grant from Bangerter-Rhyner Stiftung for the DISTAL trial. Unrestricted Grants for the DISTAL trial from Stryker Neurovascular Inc., Phenox GmbH, Penumbra Inc., and Rapid Medical Inc., Sponsor-PI SPINNERS trial (Funded by a Siemens Healthineers AG Grant), Research agreement with Siemens Healthineers AG, Local PI for the ASSIST, EXCELLENT, TENSION, COATING, SURF, and ESCAPE-NEXT trials. Speaker fees: Stryker Neurovascular Inc., Medtronic Inc., Penumbra Inc., Acandis GmbH, Phenox GmbH, Siemens Healthineers AG. ES: consults for Medtronic, Microvention, Rapid Medical. SY: received lecture fees from Stryker, Medtronic, Johnson & Johnson, Kaneka Medics. HC: Consultant for Medtronic and Microvention. JAG: Georgia Research Alliance, Emory Medical Care Foundation, Neurosurgery Catalyst, Consultant: Cognition, Imperative Care. DGR: Consultant for Penumbra, Balt, Microvention, Phenox. OT: Consulting Agreements: Viz.AI, Inc., Penumbra, Inc, Balt, Inc, Stryker Inc, Imperative Inc. Proctor: Microvention Inc, Medtronic Inc. Educational/Research Grants: Q’apel Inc, Steinberg Foundation. CM: Consultant for Stryker, Medtronic, Microvention, Penumbra, and Silk Road Medical. Speaker for Penumbra and Silk Road Medical. Contact PI for NIH Grant R21NS128641. MSP: Consultant for Medtronic. MRL: Unrestricted educational grants from Medtronic and Stryker; consulting agreement with Medtronic, Aeaean Advisers and Metis Innovative; equity interest in Proprio, Stroke Diagnostics, Apertur, Stereotaxis, Fluid Biomed, and Hyperion Surgical; editorial board of Journal of NeuroInterventional Surgery; Data safety monitoring board of Arsenal Medical. WB: Holds equity in Nested Knowledge, Superior Medical Editors, Piraeus Medical, Sonoris Medical, and MIVI Neurovascular. He receives royalties from Medtronic and Balloon Guide Catheter Technology. He receives consulting fees from Medtronic, Stryker, Imperative Care, Microvention, MIVI Neurovascular, Cerenovus, Asahi, and Balt. He serves in a leadership or fiduciary role for MIVI Neurovascular, Marblehead Medical LLC, Interventional Neuroradiology (Editor in Chief), Piraeus Medical, and WFITN. RW: Consultant for Medtronic, Stryker, and Synaptive Medical. PN: Consultant for Penumbra, Medtronic, Stryker, Cerenovus, and Balt. PK: Grants from the NIH (1U18EB029353-01) and unrestricted educational grants from Medtronic and Siemens. Consultant for Imperative Care and Stryker Neurovascular. Stock ownership in Vena Medical. RDL: PI for Imperative Trial; Research grants from Siemens Healthineers and Kaneka medical. Consultant for Cerenovus, Stryker Neurovascular and Sim & Cure. Minor equity interest Vastrax, Borvo medical, Synchron, Endostream, Von Vascular, Radical catheters, and Precision Recovery Inc. SAC: Consultant and proctor for Medtronic and Microvention. ME: Consultant for Viz.ai and Imperative care. Investments in Galaxy Therapeutics. DJA: Consultant for MicroVention, Stryker, and Cerenovus. RG: Consultant for Balt Neurovascular, Cerenovus, Medtronic Neurovascular, Rapid Medical, and Stryker Neurovascular. AMS: Consultant for Penumbra, Terumo, RapidAI, Cerenovus. AA: Consultant for Cerenovus. SSE, RAK, BM, CMC, MMS, AO, NLN, JI, PJ, JTK, SQW, AR, AA, JM, IF, AP, FS, JO, RC, MM, ED, NG: none., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Middle meningeal artery embolization (MMAE) has emerged as a promising therapy for chronic subdural hematomas (cSDHs). The efficacy of standalone MMAE compared with MMAE with concurrent surgery is largely unknown., Methods: cSDH patients who underwent successful MMAE from 14 high volume centers with at least 30 days of follow-up were included. Clinical and radiographic variables were recorded and used to perform propensity score matching (PSM) of patients treated with standalone MMAE or MMAE with concurrent surgery. Multivariable logistic regression models were used for additional covariate adjustments. The primary outcome was recurrence requiring surgical rescue, and the secondary outcome was radiographic failure defined as <50% reduction of cSDH thickness., Results: 722 MMAE procedures in 588 cSDH patients were identified. After PSM, 230 MMAE procedures remained (115 in each group). Median age was 73 years, 22.6% of patients were receiving anticoagulation medication, and 47.9% had no preoperative functional disability. Median midline shift was 4 mm and cSDH thickness was 16 mm, representing modestly sized cSDHs. Standalone MMAE and MMAE with surgery resulted in similar rates of surgical rescue (7.8% vs 13.0%, respectively, P=0.28; adjusted OR (aOR 0.73 (95% CI 0.20 to 2.40), P=0.60) and radiographic failure (15.5% vs 13.7%, respectively, P=0.84; aOR 1.08 (95% CI 0.37 to 2.19), P=0.88) with a median follow-up duration of 105 days. These results were similar across subgroup analyses and follow-up durations., Conclusions: Standalone MMAE led to similar and durable clinical and radiographic outcomes as MMAE combined with surgery in select patients with moderately sized cSDHs and mild clinical disease., Competing Interests: Competing interests: AMS: grants or contracts from Penumbra, Microvention, Medtronic, and Stryker; consulting fees from Penumbra, Terumo, and Rapid AI; co-founder of the STAR collaboration; stock or stock options in Avail Medical. AHS: grants or contracts from NIH and Brain Aneurysm Foundation; consulting fees from Amnis Therapeutics, Apellis Pharmaceuticals, Boston Scientific, Canon Medical Systems USA, Cardinal Health 200, Cerebrotech Medical Systems, Cerenovus, Cordis, Corindus, Endostream Medical, Hyperfine Operations, Imperative Care, InspireMD, Integra, IRRAS AB, Medtronic, MicroVention, Minnetronix Neuro, Peijia Medical, Penumbra, Piraeus Medical, Q’Apel Medical, Rapid Medical, Serenity Medical, Silk Road Medical, StimMed, Stryker Neurovascular, VasSol, and Viz.ai; patents planned, issued, or pending for patent No US 11,464,528 B2; stock or stock options in Adona Medical, Bend IT Technologies, BlinkTBI, Borvo Medical, Cerebrotech Medical Systems, Code Zero Medical, Cognition Medical, Collavidence, CVAID, E8, Endostream Medical, Galaxy Therapeutics, Hyperion Surgical, Imperative Care, InspireMD, Instylla, Launch NY, Neurolutions, NeuroRadial Technologies (sold to Medtronic in 2021), Neurovascular Diagnostics, Peijia Medical, PerFlow Medical, Piraeus Medical, Q’Apel Medical, QAS.ai, Radical Catheter Technologies, Rebound Therapeutics (purchased in 2019 by Integra Lifesciences), Rist Neurovascular (purchased in 2020 by Medtronic), Sense Diagnostics, Serenity Medical, Silk Road Medical, Sim & Cure, Spinnaker Medical, StimMed, Synchron, Tulavi Therapeutics, Vastrax, Viseon, Whisper Medical, and Willow Medtech; national PI/steering committees for Cerenovus (EXCELLENT and ARISE II trial), Medtronic (SWIFT-PRIME, VANTAGE, EMBOLISE, and SWIFT DIRECT trials), MicroVention (FRED trial and CONFIDENCE study), MUSC (POSITIVE trial), Penumbra (3D Separator trial, COMPASS trial, INVEST trial, MIVI neuroscience EVAQ trial), Rapid Medical (SUCCESS trial), and InspireMD (C-GUARDIANS IDE Pivotal trial).TGJ: consulting fees from Stryker, Silk Road Medical, Blockade Medical, FreeOx Biomedical, Route 92, Neurotrauma Science, Viz.ai, Corindus, Anaconda, Medtronic, Contego, Methinks DAWN, AURORA, and Stryker Neurovascular. RG: consulting fees from Medtronic, Stryker, Cerenovus, Balt, and Rapid Medical. MRL: grants or contracts from NIH, The Aneurysm and AVM Foundation, Society of NeuroInterventional Surgery, and Congress of Neurosurgeons; consulting fees from Metis Innovative and Aeaean Advisers; support for attending meetings and/or travel from Penumbra; participated on the DSMB of Arsenal Medical; serves on the editorial boards of Journal of NeuroInterventional Surgery and Frontiers in Surgery; equity interest in Hyperion Surgical, Proprio, Apertur, Cerebrotech, Synchron, Fluid Biomed, and Stereotaxis; unrestricted educational grants from Medtronic and Stryker. CSO: DSMB for Medtronic (EMBOLISE) and Contour. BAG: consultant for Medtronic, Stryker, and Microvention. PK: grants or contracts from NIH, Siemens, Medtronic, and Joe Niekro Foundation; consulting fees from Stryker Neurovascular and Imperative Care; editorial board of Journal of NeuroInterventional Surgery; stock or stock options in Vena Medical., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: The duration of mechanical thrombectomy (MT) is a negative predictor of outcomes in acute ischemic stroke (AIS), yet the precise mechanisms are unclear. We investigated whether the placement of large-bore catheters intracranially reduces blood flow to the ischemic penumbra and diminishes the efficacy of MT., Methods: We investigated the impact of different catheter sizes on flow through the intracranial circulation using an in vitro model. Data from a multicenter international registry of AIS patients undergoing MT between January 2016 and December 2023 were reviewed. Intracranial procedure time (icPT) from catheter placement to thrombectomy completion was analyzed using propensity score (PS) matched analysis of patients with successful recanalization achieved in <30 min versus ≥30 min (n=1006/group). Primary outcome was modified Rankin Scale (mRS) score at 90 days (mRS 0-2 favorable). Secondary outcomes included mortality, symptomatic intracranial hemorrhage (sICH), and need for craniectomy., Results: Using our flow model, we demonstrated a significant reduction in middle cerebral artery and anterior cerebral artery blood flow with the use of larger caliber catheters in the internal carotid artery. Controlling for covariates in 3318 patients, longer icPT predicted lower odds of 90-day favorable outcome (adjusted odds ratio (aOR) 0.87, P<0.01), increased mortality (aOR 1.03, P<0.01), higher decompressive craniectomy rates (aOR 1.07, P<0.01), and increased sICH (aOR 1.07, P<0.01). Each additional 10 mins of icPT correlated with a 13% decrease in recanalization success. The impact of icPT on outcomes was consistent regardless of recanalization success, though catheter size influenced effects. Reduced intraprocedural blood pressure worsened icPT's effects., Conclusions: This study is the first to demonstrate the risks associated with the duration of catheter use during MT and to propose strategies to mitigate these risks in AIS., Competing Interests: Competing interests: Sami Al Kasab: Grant from Stryker for RESCUE-ICAS registry. Adam Arthur: Consultant for Arsenal, Balt, Johnson and Johnson, Medtronic, Microvention, Penumbra, Perfuze, Scientia, Siemens, Stryker. Research support from Balt, Medtronic, Microvention, Penumbra, Siemens. Shareholder in several companies. Shinichi Yoshimura: Lecture fee from Stryker, Medtronic, Johnson & Johnson, Kaneka Medics. Min Park: Consultant for Medtronic. Waleed Brinjikji: Equity, royalties, consulting fees, and leadership roles in several companies including Medtronic, Stryker, and others. Charles Matouk: Consultant for Stryker, Medtronic, Microvention, Penumbra, and Silk Road Medical. Speaker for Penumbra and Silk Road Medical. Daniele Romano: Consultant for Penumbra, Balt, Microvention, Phenox. David J Altschul: Consultant for MicroVention, Stryker, and Cerenovus. Richard Williamson: Consultant for Medtronic, Stryker, and Synaptive Medical. Reade De Leacy: Research grants, consultant roles, and minor equity interest in several companies. Mohamad Ezzeldin: Speaker for Viz.ai and stocks in Galaxy Therapeutics. Peter Kan: Grants, consulting roles, stock ownership in several companies. Michael Levitt: Grants, consulting agreements, equity interests in several companies. Jonathan A Grossberg: Grant support and consulting roles in several entities. Alejandro M Spiotta: Research support from Penumbra, Microvention, Medtronic, Stryker, RapidAI, Brain Aneurysm Foundation. Consultant for Penumbra, Terumo, and RapidAI. Other authors: No conflict of interest., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Randomized clinical trials have failed to prove that the safety and efficacy of endovascular treatment for symptomatic intracranial atherosclerotic disease (ICAD) is better than that of medical management. A recent study using a self-expandable stent showed acceptable lower rates of periprocedural complications., Objective: To study the safety and efficacy of a balloon-mounted stent (BMS) in the treatment of symptomatic ICAD., Methods: Prospectively maintained databases from 15 neuroendovascular centers between 2010 and 2020 were reviewed. Patients were included if they had severe symptomatic intracranial stenosis in the target artery, medical management had failed, and they underwent intracranial stenting with BMS after 24 hours of the qualifying event. The primary outcome was the occurrence of stroke and mortality within 72 hours after the procedure. Secondary outcomes were the occurrence of stroke, transient ischemic attacks (TIAs), and mortality on long-term follow-up., Results: A total of 232 patients were eligible for the analysis (mean age 62.8 years, 34.1% female). The intracranial stenotic lesions were located in the anterior circulation in 135 (58.2%) cases. Recurrent stroke was the qualifying event in 165 (71.1%) while recurrent TIA was identified in 67 (28.9%) cases. The median (IQR) time from the qualifying event to stenting was 5 (2-20.75) days. Strokes were reported in 13 (5.6%) patients within 72 hours of the procedure; 9 (3.9%) ischemic and 4 (1.7%) hemorrhagic, and mortality in 2 (0.9%) cases. Among 189 patients with median follow-up time 6 (3-14.5) months, 12 (6.3%) had TIA and 7 (3.7%) had strokes. Three patients (1.6%) died from causes not related to stroke., Conclusion: Our study has shown that BMS may be a safe and effective treatment for medically refractory symptomatic ICAD. Additional prospective randomized clinical trials are warranted., Competing Interests: Competing interests: RGN reports consulting fees for advisory roles with Stryker Neurovascular, Cerenovus, Medtronic, Phenox, Anaconda, Genentech, Biogen, Prolong Pharmaceuticals, Imperative Care and stock options for advisory roles with Brainomix, Viz-AI, Corindus Vascular Robotics, Vesalio, Ceretrieve, Astrocyte and Cerebrotech. DCH is a consultant for Stryker and Vesalio and holds stock options at Viz.AI. AEH - 1.Consultant/speaker: Medtronic, Microvention, Stryker, Penumbra, Cerenovus, Genentech, GE Healthcare, Scientia, Balt, Viz.ai, Insera therapeutics, Proximie, NovaSignal and Vesalio. 2.Principal investigator: COMPLETE study- Penumbra, LVO SYNCHRONISE-Viz.ai. 3.Steering committee/publication committee member: SELECT, DAWN, SELECT 2, EXPEDITE II, EMBOLISE, CLEAR. 4.Proctor: Pipeline, FRED, Wingspan, and Onyx. 5.Supported by grants from: GE Healthcare. PK is on the editorial board of JNIS. The other authors report no conflicts., (© Author(s) (or their employer(s)) 2022. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: The Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke 3 (DEFUSE 3) clinical trial assessed the use of endovascular thrombectomy (EVT) during the period 6-16 hours after last normal in selected patients. This is a secondary cohort analysis of the DEFUSE 3 data assessing potential predictive variables for mortality in the EVT-treated patients., Methods: The primary outcome was death within 90 days. Patients who died and those who did not were compared statistically. We developed a predictive score using preprocedural variables that were statistically predictive of death in univariate regression analysis (P<0.1)., Results: Of the 182 patients in the DEFUSE 3 study, 92 (mean age 69 years; 50% male) met our inclusion criteria, and 15.2% of these patients met the primary outcome. Patient age, baseline National Institutes of Health Stroke Scale (NIHSS) score, wake-up stroke, statin use, and history of diabetes were statistically associated with death. Statin use did not improve the prediction score so was excluded. Thus, our model included four predictors, with one point each given for age >75 years, NIHSS ≥20, wake-up stroke, and diabetes, yielding low (0-1), moderate (2), and high (3-4) risk of death. In the low-risk, moderate-risk, and high-risk categories, 2/52 (3.9%), 3/23 (13.0%), and 9/17 (52.9%) of patients died, respectively (P<0.001)., Conclusions: Despite selective inclusion criteria and overwhelming benefit for EVT, a substantial number of EVT patients in DEFUSE 3 died. The preprocedural variables age, NIHSS, wake-up stroke, and diabetes may predict this risk. Our predictive score provides a basis for future research to determine which factors influence lethal outcome after EVT., Competing Interests: Competing interests: PT is a consultant for Covidien, Medtronic, and Stryker Neurovascular. RG is a consultant for Balt Neurovascular, Cerenovus, and Medtronic Neurovascular. GWA is supported by grants from the National Institutes of Health (NIH), is a consultant for Genentech, and a shareholder and consultant for iSchemaView. AdH is supported by NIH-NINDS K23NS105924 and receives investigator-initiated funding from AMAG and Regeneron pharmaceuticals for clinical research., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)