Multicenter US clinical experience with the Scepter Mini balloon catheter

INTRODUCTION

Distal navigability and imprecise delivery of embolic agents are two limitations encountered during liquid embolization of cerebrospinal lesions. The dual-lumen Scepter Mini balloon (SMB) microcatheter was introduced to overcome these conventional microcatheters' limitations with few small single-center reports suggesting favorable results.

METHODS

A series of consecutive patients undergoing SMB-assisted endovascular embolization were extracted from prospectively maintained registries in seven North-American centers (November 2019 to September 2022).

RESULTS

Fifty-four patients undergoing 55 embolization procedures utilizing SMB were included (median age 58.5; 48.1% females). Cranial dural arteriovenous fistula embolization was the most common indication (54.5%) followed by cranial arteriovenous malformation (27.3%). Staged/pre-operative embolization was done in 36.4% of cases; and 83.6% of procedures using Onyx-18. Most procedures utilized a transarterial approach (89.1%), and SMB-induced arterial-flow arrest concurrently with transvenous embolization was used in 10.9% of procedures. Femoral access/triaxial setups were utilized in the majority of procedures (65.5% and 60%, respectively). The median vessel diameter where the balloon was inflated of 1.8 mm, with a median of 1.5 cc of injected embolic material per procedure. Technical failures occurred in 5.5% of cases requiring aborting/replacement with other devices without clinical sequelae in any of the patients, with SMB-related procedural complications of 3.6% without clinical sequelae. Radiographic imaging follow-up was available in 76.9% of the patients (median follow-up 3.8 months), with complete occlusion (100%) or >50% occlusion in 92.5% of the cases, and unplanned retreatments in 1.8%.

CONCLUSION

The SMB microcatheter is a useful new adjunctive device for balloon-assisted embolization of cerebrospinal lesions with a high technical success rate, favorable outcomes, and a reasonable safety profile.

The Influence of Coagulopathy on Radiographic and Clinical Outcomes in Patients Undergoing Middle Meningeal Artery Embolization as Standalone Treatment for Non-acute Subdural Hematomas

Middle meningeal artery embolization (MMAE) is emerging as a safe and effective standalone intervention for non-acute subdural hematomas (NASHs); however, the risk of hematoma recurrence after MMAE in coagulopathic patients is unclear. To characterize the impact of coagulopathy on treatment outcomes, we analyzed a multi-institutional database of patients who underwent standalone MMAE as treatment for NASH. We classified 537 patients who underwent MMAE as a standalone intervention between 2019 and 2023 by coagulopathy status. Coagulopathy was defined as use of anticoagulation/antiplatelet agents or pre-operative thrombocytopenia (platelets <100,000/μL). Demographics, pre-procedural characteristics, in-hospital course, and patient outcomes were collected. Thrombocytopenia, aspirin use, antiplatelet agent use, and anticoagulant use were assessed using univariate and multivariate analyses to identify any characteristics associated with the need for rescue surgical intervention, mortality, adverse events, and modified Rankin Scale score at 90-day follow-up. Propensity score-matched cohorts by coagulopathy status with matching covariates adjusting for risk factors implicated in surgical recurrence were evaluated by univariate and multivariate analyses. Minimal differences in pre-operative characteristics between patients with and those without coagulopathy were observed. On unmatched and matched analyses, patients with coagulopathy had higher rates of requiring subsequent surgery than those without (unmatched: 9.9% vs. 4.3%; matched: 12.6% vs. 4.6%; both p < 0.05). On matched multivariable analysis, patients with coagulopathy had an increased odds ratio (OR) of requiring surgical rescue (OR 3.95; 95% confidence interval [CI] 1.68-9.30; p < 0.01). Antiplatelet agent use (ticagrelor, prasugrel, or clopidogrel) was also predictive of surgical rescue (OR 4.38; 95% CI 1.51-12.72; p = 0.01), and patients with thrombocytopenia had significantly increased odds of in-hospital mortality (OR 5.16; 95% CI 2.38-11.20; p < 0.01). There were no differences in follow-up radiographic and other clinical outcomes in patients with and those without coagulopathy. Patients with coagulopathy undergoing standalone MMAE for treatment of NASH may have greater risk of requiring surgical rescue (particularly in patients using antiplatelet agents), and in-hospital mortality (in thrombocytopenic patients).

General Versus Nongeneral Anesthesia for Middle Meningeal Artery Embolization for Chronic Subdural Hematomas: Multicenter Propensity Score Matched Study

BACKGROUND AND OBJECTIVES

The choice of anesthesia type (general anesthesia [GA] vs nongeneral anesthesia [non-GA]) in middle meningeal artery embolization (MMAE) procedures for chronic subdural hematomas (cSDH) differs between institutions and left to care team discretion given lack of standard guidelines. We compare the outcomes of GA vs non-GA in MMAE.

METHODS

Consecutive patients receiving MMAE for cSDH at 14 North American centers (2018-2023) were included. Clinical, cSDH characteristics, and technical/clinical outcomes were compared between the GA/non-GA groups. Using propensity score matching (PSM), patients were matched controlling for age, baseline modified Rankin Scale, concurrent/prior surgery, hematoma thickness/midline shift, and baseline antiplatelet/anticoagulation. The primary end points included surgical rescue and radiographic success rates (≥50% reduction in maximum hematoma thickness with minimum 2 weeks of imaging). Secondary end points included technical feasibility, procedural complications, and functional outcomes.

RESULTS

Seven hundred seventy-eight patients (median age 73 years, 73.2% male patients) underwent 956 MMAE procedures, 667 (70.4%) were non-GA and 280 were GA (29.6%). After running 1:3 PSM algorithm, this resulted in 153 and 296 in the GA and non-GA groups, respectively. There were no baseline/procedural differences between the groups except radial access more significantly used in the non-GA group (P = .001). There was no difference between the groups in procedural technical feasibility, complications rate, length of stay, surgical rescue rates, or favorable functional outcome at the last follow-up. Subsequent 1:1 sensitivity PSM retained the same results. Bilateral MMAE procedures were more performed under non-GA group (75.8% vs 67.2%; P = .01); no differences were noted in clinical/radiographic outcomes between bilateral vs unilateral MMAE, except for longer procedure duration in the bilateral group (median 73 minutes [IQR 48.3-100] vs 54 minutes [39-75]; P < .0001). Another PSM analysis comparing GA vs non-GA in patients undergoing stand-alone MMAE retained similar associations.

CONCLUSION

We found no significant differences in radiological improvement/clinical outcomes between GA and non-GA for MMAE.

Transvenous Embolization of Dural Arteriovenous Fistulas Through the Galenic (Deep Venous) System: Multicenter Case Series and Meta-Analysis

BACKGROUND AND OBJECTIVES

Arteriovenous fistulas involving the deep venous system have often been treated with microsurgery or transarterial embolization. Increasing familiarity with transvenous navigation and improved endovascular access systems may facilitate transvenous embolization (TVE) for these rare and challenging lesions.

METHODS

We performed a retrospective study of neurointerventional databases of 6 high-volume centers. We identified all cases of arteriovenous fistulas with deep transvenous embolizations for arteriovenous fistula. Details regarding demographics, fistula characteristics, treatment considerations, clinical outcomes, and fistula occlusion were obtained and analyzed. The meta-analysis used the same inclusion criteria.

RESULTS

Seventeen cases of TVE were identified. The most common reasons for TVE included prior treatment failure with microsurgery (n = 2) or transarterial embolization (n = 3) or inaccessible arterial pedicles (n = 4). For patients with full clinical outcome data (n = 14), 2 patients had worsened modified Rankin Scale, 8 patients had no change, and 4 were improved at a median clinical follow-up of 3.5 months. Angiographic obliteration was achieved in 15/17 cases (88.2%). In 1 case, catheterization around a sharp turn in the basal vein of Rosenthal could not be performed. In another case, despite successful TVE, there was residual lesion which was treated 1 year later by microsurgical clipping and excision.

CONCLUSION

Transvenous approaches for embolization of deep arteriovenous fistulas have become possible with modern endovascular catheter systems and liquid embolics. These lesions can be treated safely and effectively through endovascular approaches, which may spare patients the traversal of deep structures needed for microsurgical approaches to these regions. The outcomes of TVE are comparable with published outcomes of microsurgical interruption.

Middle Meningeal Artery Embolization for Chronic Subdural Hematoma: Predictors of Clinical and Radiographic Failure from 636 Embolizations

Background Knowledge regarding predictors of clinical and radiographic failures of middle meningeal artery (MMA) embolization (MMAE) treatment for chronic subdural hematoma (CSDH) is limited. Purpose To identify predictors of MMAE treatment failure for CSDH. Materials and Methods In this retrospective study, consecutive patients who underwent MMAE for CSDH from February 2018 to April 2022 at 13 U.S. centers were included. Clinical failure was defined as hematoma reaccumulation and/or neurologic deterioration requiring rescue surgery. Radiographic failure was defined as a maximal hematoma thickness reduction less than 50% at last imaging (minimum 2 weeks of head CT follow-up). Multivariable logistic regression models were constructed to identify independent failure predictors, controlling for age, sex, concurrent surgical evacuation, midline shift, hematoma thickness, and pretreatment baseline antiplatelet and anticoagulation therapy. Results Overall, 530 patients (mean age, 71.9 years ± 12.8 [SD]; 386 men; 106 with bilateral lesions) underwent 636 MMAE procedures. At presentation, the median CSDH thickness was 15 mm and 31.3% (166 of 530) and 21.7% (115 of 530) of patients were receiving antiplatelet and anticoagulation medications, respectively. Clinical failure occurred in 36 of 530 patients (6.8%, over a median follow-up of 4.1 months) and radiographic failure occurred in 26.3% (137 of 522) of procedures. At multivariable analysis, independent predictors of clinical failure were pretreatment anticoagulation therapy (odds ratio [OR], 3.23; P = .007) and an MMA diameter less than 1.5 mm (OR, 2.52; P = .027), while liquid embolic agents were associated with nonfailure (OR, 0.32; P = .011). For radiographic failure, female sex (OR, 0.36; P = .001), concurrent surgical evacuation (OR, 0.43; P = .009), and a longer imaging follow-up time were associated with nonfailure. Conversely, MMA diameter less than 1.5 mm (OR, 1.7; P = .044), midline shift (OR, 1.1; P = .02), and superselective MMA catheterization (without targeting the main MMA trunk) (OR, 2; P = .029) were associated with radiographic failure. Sensitivity analyses retained these associations. Conclusion Multiple independent predictors of failure of MMAE treatment for chronic subdural hematomas were identified, with small diameter (<1.5 mm) being the only factor independently associated with both clinical and radiographic failures. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Chaudhary and Gemmete in this issue.

Middle meningeal artery embolization as a perioperative adjunct to surgical evacuation of nonacute subdural hematomas: An multicenter analysis of safety and efficacy

BACKGROUND

By 2030, nonacute subdural hematomas (NASHs) will likely be the most common cranial neurosurgery pathology. Treatment with surgical evacuation may be necessary, but the recurrence rate after surgery is as high as 30%. Minimally invasive middle meningeal artery embolization (MMAE) during the perioperative period has been posited as an adjunctive treatment to decrease the potential for recurrence after surgical evacuation. We evaluated the safety and efficacy of concurrent MMAE in a multi-institutional cohort.

METHODS

Data from 145 patients (median age 73 years) with NASH who underwent surgical evacuation and MMAE in the perioperative period were retrospectively collected from 15 institutions. The primary outcome was the rate of recurrence requiring repeat surgical intervention. We collected clinical, treatment, and radiographic data at initial presentation, after evacuation, and at 90-day follow-up. Outcomes data were also collected.

RESULTS

Preoperatively, the median hematoma width was 18 mm, and subdural membranes were present on imaging in 87.3% of patients. At 90-day follow-up, median NASH width was 6 mm, and 51.4% of patients had at least a 50% decrease of NASH size on imaging. Eight percent of treated NASHs had recurrence that required additional surgical intervention. Of patients with a modified Rankin Scale score at last follow-up, 87.2% had the same or improved mRS score. The total all-cause mortality was 6.0%.

CONCLUSION

This study provides evidence from a multi-institutional cohort that performing MMAE in the perioperative period as an adjunct to surgical evacuation is a safe and effective means to reduce recurrence in patients with NASHs.

Abstract P476: Safety and Efficacy of Balloon Mounted Drug-Eluting Stent in the Treatment of Symptomatic Intracranial Atherosclerotic Disease Multicenter International Experience

Introduction: Intracranial atherosclerotic disease (ICAD) is a common cause of refractory stroke. Randomized clinical trials failed to prove the safety and efficacy of the endovascular treatment options of symptomatic ICAD (sICAD). However, there are many concerns regarding inclusion criteria in these trials which made them less effective than standard medical management. Herein, we aim to study the safety and efficacy of drug-eluting balloon mounted stents (DES) in the treatment of sICAD.

Methods: A retrospective review of endovascular database from 10 comprehensive stroke centers inside and outside the USA from January 2017 to January 2020 was reviewed. Patients were included if they had symptomatic intracranial stenosis ≥70% in the target vessel, failed best medical management, and underwent intracranial stenting with DES. The primary outcome was the occurrence of ischemic stroke, hemorrhage, or mortality within 72 hours of the procedure. Secondary outcomes included rates of symptomatic and angiographic recurrence within 6 months of the procedure.

Results: There was a total of 129 patients, the median age was 65 [58-72] years, 40 (31%) were females. The intracranial stenotic lesions were located in anterior circulation in 74 (57.4%) of cases [24 (18.6%) supraclinoid ICA, 5 (3.9%) cavernous ICA, 17 (13.2%) petrous ICA, 5 (19.4%) MCA-M1, and 3 (2.3%) M2] and in posterior circulation in 55 (42.6%) of cases [36 (27.9) vertebral artery V4 segment, 18 (14%) basilar and 1 (0.7%) PCA]. Recurrent stroke was the qualifying event in 101 (78.3%) while transient ischemic attacks (TIA) were identified in 28 (21.7%) of cases. The median time from the qualifying event to stenting was 6 [2-24] days. Strokes were reported within 72 hours of the procedure; 2 (1.6%) ischemic, 2 (1.6%) hemorrhagic strokes and 2 (1.6%) patients suffered inpatient mortality. The median follow-up time was 6 [3-6.75] months. Among 99 patients who had clinical follow up 2 (2%) had TIA and 6 (6.1%) had strokes. Fifty-one patients had follow-up imaging of whom symptomatic ISR was reported in 8 (15.7%).

Conclusion: Our study has shown that in appropriately selected patients with sICAD, endovascular treatment using DES is safe and effective. Prospective randomized clinical trials are warranted.

Safety and Efficacy of Stent-assisted Coiling in the Treatment of Unruptured Wide-necked Intracranial Aneurysms: A Single-center Experience

Introduction: Wide-necked intracranial aneurysms (IAs) are complex lesions that may require different microsurgical or endovascular strategies, and stent-assisted coiling (SAC) has emerged as a feasible alternative to treat this subset of aneurysms.

Methods: The objective was to assess the rate of complications of unruptured wide-necked IAs treated with SAC. We retrospectively identified patients with unruptured wide-necked IAs treated with SAC. Medical charts, procedure reports, and imaging studies were analyzed.

Results: One hundred twenty patients harboring 124 unruptured wide-necked IAs were included. Ninety-two aneurysms (74.2%) were located in the anterior circulation. The median aneurysm size was 7 mm (IQR = 5-10). The immediate complete aneurysm occlusion rate was 29% (36/124). The rate of procedural complications was 3.3 % (4/120), which included 2 intraprocedural aneurysm ruptures, 1 immediate postprocedure aneurysm rupture, and 1 vessel occlusion rescued with an open-cell stent. The median follow-up time was 21 months (IQR = 10.3-40.9). Kaplan-Meier analysis estimated a median time of complete aneurysm occlusion of 6.3 months (95%CI = 3.8-7.8). At 30-day follow-up, 80.7% of patients had a Glasgow Outcome Score (GOS) of 5 and at the latest follow-up 83.9%. Imaging follow-up was available for 102 patients. The rate of complete aneurysm occlusion was 73.5% (75/102), severe in-stent stenosis (>50%) was found in 1% (1/102), the recanalization rate was 6.6% (5/75), and the retreatment rate was 7.8% (8/102).

Conclusion: SAC remains a safe and effective technique to treat wide-necked IAs, providing a low rate of complications and recanalization with excellent long-term aneurysm occlusion rates.

Referral facility CT perfusion prior to inter-facility transfer in patients undergoing mechanical thrombectomy

BACKGROUND AND PURPOSE

The use of CT perfusion (CTP) imaging at a referring hospital is feasible and may shorten the door to puncture time for patients with acute ischemic stroke.

METHODS

We conducted a single center retrospective review of a prospectively maintained database of consecutive ischemic stroke patients transferred to our center for consideration of endovascular therapy. Patients were divided into two groups. Group 1 consisted of patients transferred from facilities where CTP (using automated RAPID software) was routinely performed and group 2 consisted of patients transferred from facilities that did not perform perfusion imaging.

RESULTS

We identified a total of 132 patients, all of whom were transferred to our center, from April 2014 to April 2017. There were no differences in baseline characteristics between the two groups. A total of 34 patients were transferred from a facility after CTP (group 1) and 98 were transferred from a facility with no CTP (group 2). Door to puncture time was significantly shorter for patients in group 1 compared with those in group 2 (median 12 (IQR 8-16) min and 48.5 (32.8-71.8) min, respectively; P<0.001). Despite obtaining additional pre-transfer imaging in group 1, there was no difference in door in and door out times at the referring facilities compared with group 2.

CONCLUSIONS

We found that triaging from a primary stroke center after CTP RAPID was feasible and significantly reduced the door to puncture time without any significant delay in the transfer process.