Caroff, Jildaz

BACKGROUND AND OBJECTIVES: Embolization is part of multidisciplinary brain arteriovenous malformations (AVMs) treatment, yet safety data for novel liquid embolization agents (LEAs) such as Squid and PHIL remain limited. This study reports complications and outcomes from curative embolization using Onyx, Squid, PHIL, and Glue. METHODS: Adult patients with brain AVMs treated with LEAs from July 2015 to December 2022 were reviewed for intraprocedural technical issues, postoperative hemorrhagic, and ischemic complications. Minor (modified Rankin Scale ≤2) and major complication rate (morbidity/modified Rankin Scale >2), mortality, and 6-month angiographic cure rate were evaluated. RESULTS: In total, 135 patients (62.2% male, mean age 41.7 ± 15.1 years) with 206 embolizations (34% Onyx, 18.9% Squid, 17.5% PHIL, 28.2% Glue) were included. Overall, 87.4% procedures were in ruptured AVMs and 84% treated by the transarterial technique (84%). The 6-month angiographic cure rate was 53.3%, higher when nonadhesive LEAs were used than Glue (65.3% vs 17.6%, P < .001). In adjusted analysis, only eloquent location (odds ratio [OR] = 4.4; P = .007) and Glue (OR = 9.1; 95% CI 2.9-28.9, P < .001) were predictors of lower angiographic occlusion rate, whereas size had an inverse correlation (OR = 0.67; P = .019). Technical procedural complications, hemorrhagic, and ischemic rates were 10.2% (2.2% morbidity), 13.1% (3.7% morbidity and 2.2% mortality), and 9.2% (2.2% morbidity, 0% mortality), respectively, regardless of the preferred LEA. Minor, major complications, and mortality rates were 3.7%, 4.4%, and 2.2%, respectively. Hemorrhage was the major contributor to morbidity and mortality, whereas deep venous drainage was an independent predictor of hemorrhage and mortality. CONCLUSION: PHIL and Squid demonstrated complication and angiographic cure rates comparable with Onyx. However, curative embolization of brain AVMs resulted in only moderate angiographic occlusion. Larger multicenter studies with standardized operator protocols, cost-effectiveness assessments, and extended follow-up are warranted to validate these findings.

OBJECTIVE Many patients recruited in the Treatment of Brain Arteriovenous Malformations Study (TOBAS) are managed conservatively. The aim of this study was to monitor what happened to those patients. METHODS TOBAS comprises two randomized controlled trials and multiple prospective registries. All patients with brain arteriovenous malformations (AVMs) can participate. This report concerns patients selected for conservative management. The primary trial outcome measure is related death or dependency (modified Rankin Scale [mRS] score > 2) at 10 years. Secondary outcomes include intracranial hemorrhages, nonhemorrhagic neurological events, and serious adverse events (SAEs). For this report, outcome results are presented using patient-years, Kaplan-Meier survival curves, and Cox log-rank tests. There was no blinding. RESULTS From June 2014 to May 2021, 1010 patients were recruited, of whom 498 (49%) were proposed the prospective observation registry. After exclusions, 434 (87%) patients remained for analysis. The majority of patients had unruptured AVMs (378/434 [87%]), of which 195 (52%) were low grade (Spetzler-Martin grade I or II). During a mean follow-up period of 3.2 years (total 1368 patient-years), the primary outcome occurred in 23 of 434 (5%) patients, corresponding to an incidence of 1.7 (95% CI 1.1–2.5) per 100 patient-years. For unruptured AVMs the incidence was 1.1 (95% CI 0.7–1.9) per 100 patient-years, and for low-grade unruptured AVMs it was 0.6 (95% CI 0.2–1.7) per 100 patient-years. Poor outcomes were more frequent in patients with a history of rupture (HR 5.6 [95% CI 2.4–13.0], p < 0.001), infratentorial AVMs (HR 2.9 [95% CI 1.1–7.3], p = 0.027), and age ≥ 55 years (HR 3.2 [95% CI 1.4–7.6], p = 0.007). Major intracranial hemorrhage occurred in 35 of 434 (8%) patients (incidence of 2.6 [95% CI 1.9–3.6] per 100 patient-years; 2.0 [95% CI 1.3–2.9] per 100 patient-years for unruptured AVMs and 1.3 [95% CI 0.6–2.6] per 100 patient-years for low-grade unruptured AVMs). Major AVM hemorrhages were more frequent in ruptured (HR 4.4 [95% CI 2.1–8.9], p < 0.001), large (HR 2.6 [95% CI 1.1–6.6], p = 0.039), and high-grade (HR 2.5 [95% CI 1.2–5.3], p = 0.013) AVMs and those with deep venous drainage (HR 2.1 [95% CI 1.1–4.2], p = 0.032). SAEs occurred in 48 of 434 (11%) patients (incidence of 3.6 [95% CI 2.7–4.8] per 100 patient-years). For unruptured AVMs the incidence was 2.8 (95% CI 2.0–4.0) per 100 patient-years, and for low-grade unruptured AVMs it was 1.8 (95% CI 1.0–3.2) per 100 patient-years. CONCLUSIONS Nearly half of TOBAS participants were observed. Rates of untoward neurological events were within expected boundaries.

Background Although flow diverters (FDs) have benefited from several technical improvements, recently concerns have arisen regarding the braid stability after implantation. Thus, we investigated frequency, predictive factors, and clinical impact of the phenomenon of FD braid deformation (FDBD). Methods Consecutive intracranial aneurysms (IAs) treated with various FDs, between January 2018 and July 2023, were reviewed to identify FDBD (defined as the deformation of a FD without any external force applied to it). Patient, aneurysm, procedural, and FD characteristics were retrieved and analyzed using univariate and multivariable analyses. Morbidity is defined as a score of +1 in the modified Rankin Scale at 3 months. Results In total, 245 FD procedures (271 FDs implanted; 25 multiple IAs treated with 1 FD) in 228 patients; FDBD was observed in 36/245 cases (14.7%), mainly at follow-up angiography (32/36, 88.9%); fish-mouthing was the most frequent FDBD. Morbidity was related to fish-mouthing and braid collapse and was significantly higher in the FDBD group after retreatment (p=0.04). Drawn filled tubing with platinum (DFT) (adjusted odds ratio (aOR)=7.0, 95% CI 3.0 to 17.5; p<0.001) and FD diameter (aOR=2.2, 95% CI 1.3 to 4.1; p<0.01) were identified as independent predictors of FDBD. The metal alloy composing the FD (p=0.13) and coated surfaces were not significantly associated with FDBD (p=0.54 in multivariable analysis). Conclusions FDBD is a frequent phenomenon observed in about 15% of cases, and it was responsible for higher morbidity. Only FD characteristics (DFT and FD diameter) were independent determinants of FDBD. Future research should focus on the impact of novel braid configurations and materials on braid stability.

Background Sealing of the aneurysm neck with a Woven EndoBridge (WEB) device is recommended for disrupting the blood flow inside the aneurysm. This study investigates the relationship between WEB neck apposition and aneurysm occlusion rates. Methods Aneurysms treated with a WEB from March 2017 to May 2022 at a single center were included. WEB neck apposition (poor/good) and WEB protrusion (yes/no) were evaluated on post-detachment high resolution cone beam CT images. Angiographic occlusion was assessed with the Bicêtre Occlusion Scale score (BOSS). Univariate and multivariable analysis tested the association between neck apposition and occlusion rates. Results The study included 159 aneurysms in 141 patients (mean age 55.8±11.2 years; 64.2% women). Good neck apposition and protrusion were noted in 123 (77.4%) and 30 (18.9%) cases, respectively. Inter-rater agreements were good for neck apposition (κ=0.75) and protrusion (κ=0.78). Complete and adequate occlusion was achieved in 104 (65%) and 130 (82%) cases, respectively (median follow-up 18 months). Good neck apposition was a strong independent predictor for both adequate (adjusted OR (aOR)=5.9, 95% CI 2.4 to 14.9; P<0.001) and complete occlusion (aOR=7.1, 95% CI 3.0 to 18.1; P<0.001). Protrusion was more frequent in the adequate occlusion group versus the aneurysm recurrence group without reaching statistical significance (P=0.06), but was associated with more thromboembolic complications (9/30 (30%) vs 12/129 (9%); P<0.01). WEB shape modification was significantly greater in poor apposition cases (P=0.03). Conclusions Achieving good neck apposition of the WEB strongly predicts aneurysm occlusion during follow-up. WEB protrusion should be minimized due to the increase in thromboembolic risk with limited impact on aneurysm occlusion.

Background Mycotic and oncotic aneurysms may result in devastating neurologic sequelae if undetected. The objectives of this study were to examine interobserver variability and accuracy of cross-sectional imaging for the detection of distal territory mycotic and oncotic aneurysms. Methods We searched our institutional database for all radiology reports from 2005 to 2015 with an indication or diagnosis of mycotic or oncotic aneurysm. Patients who underwent DSA and either CTA or MRA within 12 weeks of each other were identified. The cross-sectional images from each study were blinded and reviewed by two radiologists. If positive for aneurysm, location and number of aneurysms were reported. Sensitivity, specificity, positive predictive value, negative predictive value, and interobserver variability were determined for MRA and MRA/CTA. Results Twenty-five patients were included in this study. Ten (40%) harbored distal aneurysms. Cross-sectional imaging had a sensitivity of 45.5%, specificity of 90.0%, and kappa value of 0.29 (0.00–0.69) for the detection of cerebral mycotic and oncotic aneurysms. Conclusions Because of the low sensitivity and high interobserver variability of cross-sectional imaging, DSA should remain the gold standard for evaluation of suspected oncotic and mycotic aneurysms. In cases in which cross sectional imaging is negative and there is a high clinical suspicion for mycotic aneurysm, DSA should be strongly considered.