Symptomatic modifications of side branches after flow diverter treatment depend on the extent and type of collateral supply.

This prospective contemporary series demonstrates a high rate of complete AVM obliteration and excellent functional outcomes in patients with both ruptured and unruptured AVMs treated with transvenous embolization. This approach is promising and warrants further investigation as a treatment for select AVMs.

OBJECT Ruptured cerebral arteriovenous malformations (AVMs) with deep localization and high Spetzler-Martin grades are associated with considerable challenges regarding nidus eradication treatment. The authors report their experience with curative endovascular transvenous embolization in a series of patients harboring “untreatable” lesions. METHODS Between January 2008 and June 2013, a transvenous endovascular embolization protocol was implemented at the authors' institution for consecutive patients with ruptured brain AVMs that were considered incurable by classic endovascular and surgical techniques. Therapeutic decision making was based on Spetzler-Martin grades, AVM location, type of venous drainage, and angioarchitectural evaluation. Complete exclusion of the nidus was the objective of treatment. RESULTS Twenty patients (10 male and 10 female, mean age 36.7 ± 17.7 years) were included. Initial Spetzler-Martin grades were III–V for 90.0% of the patients. The lesions were deeply seated in 80% and in eloquent locations in 90% of cases. The preprocedural modified Rankin Scale score was 0–2 for 12 of the 20 patients (60.0%), 3 for 2 patients (10.0%), and 4 for 6 patients (30.0%). The postprocedural clinical status was unchanged for all patients. The procedure was technically feasible in all cases. Procedure-related mortality was 0%. Ninety percent of the patients were independent in their everyday lives (modified Rankin Scale Scores 0–2) at the 6-month follow-up. In all cases but one (95%) the embolization was curative, confirmed by selective DSA at 6 months and 18 months postintervention. CONCLUSIONS Single-session endovascular transvenous embolization seems to be a safe and effective curative treatment for patients harboring complex brain AVMs with high Spetzler-Martin grade.