Results of surgical and endovascular treatment of intracranial micro-arteriovenous malformations with emphasis on superselective angiography

BACKGROUND: The authors retrospectively reviewed the results of two different treatment modalities (surgery and endovascular approach) in patients with intracranial micro-arteriovenous malformations (micro-AVMs). The goal of this study is to evaluate the respective role of surgical treatment and superselective acrylic embolization in the management of micro-AVMs. METHOD: Fourteen patients with micro-AVMs who had been treated by surgical resection or endovascular acrylic embolization during a 6-year period were analyzed. The average age at presentation was 44.6 years (range, 24-65 yr) with no sex dominance. All patients presented with an intracranial haemorrhage, which was superficial in twelve patients and in eloquent brain areas in seven patients. Severe neurological deficits were observed in eleven patients. FINDINGS: Digital subtraction angiography (DSA) demonstrated micro-AVMs in eleven patients (78.5%) while in three patients (21.5%) the micro-AVM was detected only by superselective angiography (SA). Eight patients underwent surgical intervention which led to definitive resection in seven with no peri-operative morbidity. SA was performed in nine patients and followed by successful acrylic embolization of the micro-AVM in seven with haemorrhagic complications in two patients. All fourteen lesions were completely obliterated as demonstrated angiographically. Outcomes were classified according to the Modified Rankin Scale. With a mean long term clinical follow-up of 33 months (range, 8-75 mo), seven patients were Grade 0, six patients were Grade I and one patient was Grade IV. CONCLUSIONS: SA is deemed necessary to visualize micro-AVMs in case of questionable or negative findings also at delayed DSA in young healthy patients with otherwise unexplained intracranial haemorrhage. Obliteration of micro-AVM can be accomplished either surgically or endovascularly; however, the endovascular approach is associated with a defined procedural risk for haemorrhagic complications and long term angiographic follow-up is necessary.