Abstract
BACKGROUND AND PURPOSE: We report our initial experience with (iht)Obtura, a novel nonadhesive liquid embolic agent (LEA) with progressive postembolization loss of radiopacity for curative embolization of brain AVMs (bAVMs). MATERIALS AND METHODS: A post hoc analysis of the CLARIDAD trial, a single-center, first-in-human study, was performed. Collected data on consecutive patients with bAVMs treated with (iht)Obtura (between November 2021 and September 2022) were analyzed. Patient demographics, AVM characteristics, procedure details, and clinical treatment outcomes were collected. Imaging end points included complete occlusion rate at 6 months and loss of radiopacity at 4-6 weeks. RESULTS: A total of 42 consecutive patients with bAVM who underwent 102 embolization procedures were included in the analysis. Most patients presented with intracranial hemorrhage (83%). The mean AVM classification was Spetzler-Martin (S-M) grade III-IV (90%), with a mean nidus size of 39 ± 14 mm. Complete occlusion was achieved in 26 of 28 patients (93%) who were able to complete all treatments during the study period. In the entire patient cohort, complete occlusion was observed in 62% (26/42 patients). Procedure-related disabling permanent neurologic deficit and procedure-related death were observed in 1 case each. Both events were related to postembolization intracranial hemorrhages. Progressive reduction of embolic material radiopacity was observed in all patients. CONCLUSIONS: (iht)Obtura is a new LEA with similar properties as other currently available ethylene-vinyl alcohol copolymer (EVOH)-based liquid embolics with 1 major innovation-progressive reduction in embolic material radiopacity. This feature significantly improves anatomic understanding of residual AVM components during staged treatment of AVMs. This study provides initial evidence that the combination of EVOH-based diffusion properties with progressive loss of radiopacity allows for the potential improvement in rates of complete obliteration for bAVMs.