Target Embolization of AVMs: Identification of Sites and Results of Treatment

Abstract

Although cure of cerebral arteriovenous malformations (AVMs) is the ideal goal it is often only possible with smaller sized lesions. This is certainly true if surgery or radiotherapy is used as the treatment strategy. Endovascular treatment, however, allows the possibility of partial treatment directed at specific areas of AVM architecture. With this in mind we retrospectively reviewed our cohort of AVMs to establish which morphological areas we had identified as targets and how the treatment of the AVM influenced the clinical picture. Over a 36-month period 42 AVMs were treated. In 22 of the patients who presented with a hemorrhage an intranidal aneurysm was identified as a target and treated in nine patients. Other patients presented with headaches (2), neurological deficit (4) and seizures (16) with two patients having their AVM picked up coincidentally. Targets identified included high flow fistulas (12), decreasing venous flow (17) and cure of the AVM (8). Results of targeted treatment showed a lower rehemorrhage rate than anticipated by the natural history. Patients cured did best and targeted embolization improved seizures in nine patients, neurological deficit in four patients and headache in 20 patients. Until safer methods exist to cure large AVMs the use of targeted embolization is acceptable as it protects patients against rehemorrhage and translates into an improvement in their clinical picture.