Intracranial arterial fenestrations associated with arteriovenous malformations diagnosed by CT angiography

Fenestrations involving aneurysms have been well documented. Only sporadic papers have been reported on fenestrations associated with AVMs (arteriovenous malformations) with few cases. Our study is to determine the rate of co-occurrence of fenestrations and AVMs and to analyze the possible relationship between them by CTA.Between January 2006 and February 2012, the CTA data of 5,657 consecutive patients were retrospectively reviewed.A total of 12 cases (.21%) of fenestrations associated with AVMs were found. Of these, single-fenestrations were identified in 9 cases, and multifenestrations were found in 3 cases. Among 349 fenestrations, there were 15 cases of multifenestrations. The frequency of multifenestrations among fenestrated patients without AVMs was 3.6%. There was no significant difference in the incidence of AVMs in cases with and without fenestrations (3.4% and 2.7%), and there was no significant difference in the incidence of fenestration in cases with and without AVMs (7.7% and 6.1%, χ(2) = .643, P = .423).CTA may play a vital role in assessing the anomalies of co-occurring AVM and fenestration, with an incidence of .21%. The frequency of multifenestrations in fenestrated cases with AVMs was higher than those without AVMs, though there is no significant association between fenestrations and AVMs.