Endovascular treatment as the main approach for Spetzler-Martin grade III brain arteriovenous malformations

Background Because Spetzler-Martin (SM) grade III brain arteriovenous malformations (bAVMs) constitute a heterogeneous group of lesions with various combination of sizes, eloquence, and venous drainage patterns, their management is usually challenging. The aim of this study is to evaluate the clinical/imaging outcomes and the procedural safety of endovascular approach as the main treatment for the cure of SM grade III bAVMs. Methods In this retrospective study, prospectively collected data of SM grade III bAVMs treated by endovascular techniques between 2010 and 2018 at our hospital were reviewed. Patients older than 16 years with angiographic follow-up of at least 6 months after endovascular treatment were entered in the study. The patients had a mean follow-up of 12 months. The data were assessed for clinical outcome (modified Rankin Scale), permanent neurological deficit, post-operative complications, and optimal imaging outcome, defined by complete exclusion of AVM. The independent predictive variables of poor outcome or hemorrhagic complication were assessed using binary logistic regression. Results Sixty-five patients with 65 AVMs were included in the study. Mean age of the patients was 40.0 +/- 14.4. Most common presentation was hemorrhage (61.5%). The patients underwent one to eight endovascular procedures (median=2). Mean nidus diameter was 30.2 +/- 13.0. A complete obliteration of AVM was achieved in 57 patients (87.7%). Post-procedure significant hemorrhagic and ischemic complications were seen in 13 (20%) and five (7.7%) patients respectively, leading to five (7.7%) transient and four (6.2%) permanent neurological deficits. Eight patients (12.3%) experienced worsening of mRS after embolization. Ten patients (15.4%) had poor outcome (mRS 3-5) at follow-up and two (3%) died. Conclusions Endovascular treatment can achieve a high rate of complete exclusion of grade III AVM but may be associated (as in other treatment modalities) with significant important complications. Clinical trial registration number NCT02879071.