Background Brain arteriovenous malformations (AVMs) are a rare pathology, and their treatment is discussed. The development of techniques and materials in endovascular, radiosurgical, and neurosurgical fields led to higher rates of complete occlusions and good clinical outcomes.

Materials and methods 84 patients (52 men, 32 women; mean age 38.2 years; range, 9–70 years) were treated at our institution with Onyx18 from 2001 to 2011. Patients treated with other embolic agents, with micro-AVMs, were not included in the analysis.

Results Complete occlusion was achieved in 27/84 patients (32.2%), in 40/84 (47.6%) brain AVMs occlusion of 80–90% of the nidus was obtained, and in 17/84 (20.3%) cases <80% of the nidus was occluded. Intraprocedural adverse events occurred in 11/84 patients (13.1%), and overall mortality and disabling permanent morbidity were 2.3% (2/84) and 4.7% (4/84), respectively.

Conclusions Endovascular treatment may be considered a safe and effective approach in superficial small brain AVMs in addition to surgery, mostly in ruptured AVMs. The therapeutic strategy should be to cure small and medium AVMs with endovascular treatment alone or combined treatment. Large unruptured AVMs (Spetzler–Martin grades IV–V) should be treated with target embolization of high flow fistulas or intranidal aneurysms.