Exclusion treatment of ruptured and unruptured low-grade brain arteriovenous malformations: a systematic review.

PURPOSE To assess the obliteration rate, functional outcome, hemorrhagic complication, and mortality rates of exclusion treatment of low-grade brain arteriovenous malformations (BAVMs) (Spetzler and Martin grades (SMGs) 1 and 2), either ruptured or unruptured. METHODS Electronic databases-Ovid MEDLINE and PubMed-were searched for studies in which there was evidence of exclusion treatment of low-grade BAVMs treated either by endovascular, surgical, radiosurgical, or multimodality treatment. The primary outcome of interest was angiographic obliteration post-treatment and at follow-up. The secondary outcomes of interest were functional outcome (mRS), mortality rate, and hemorrhagic complication. Descriptive statistics were used to calculate rates and means. RESULTS Eleven studies involving 1809 patients with low-grade BAVMs were included. Among these, 1790 patients treated by either endovascular, surgical, radiosurgical, or multimodality treatment were included in this analysis. Seventy-two percent of BAVMs were Spetzler-Martin grade II. The overall (i.e., including all exclusion treatment modalities) complete obliteration rate ranged from 36.5 to 100%. The overall symptomatic hemorrhagic complication rate ranged from 0 to 7.3%; procedure-related mortality ranged from 0 to 4.7%. CONCLUSION Our systematic review of the literature reveals a high overall obliteration rate for low-grade BAVMs, either ruptured or unruptured, with low mortality rate and an acceptable post-treatment hemorrhagic complication rate. These results suggest that exclusion treatment of low-grade BAVMs may be safe and effective, regardless of the treatment modality chosen.