De novo arteriovenous malformations: case report and review of the literature.

Intracerebral arteriovenous malformations (AVMs) are traditionally recognized as congenital lesions. However, with the advent of frequent, noninvasive imaging of the brain, that notion has been challenged. We describe another patient with a de novo cerebral arteriovenous malformation and evaluate the reported literature for trends in the development of these lesions. Cases were selected from the English literature using the PUBMED database using the search term "acquired or de novo cerebrovascular arteriovenous malformations". A total of seven patients (including the one reported in this study) with de novo arteriovenous malformations are reported. Majority of patients were female, and mostly diagnosed as children. Their mean age at diagnosis was 18 years (6-32), and the mean time from the initial intracranial study to the diagnosis of an AVM was 8 years (3-17). De novo formation of AVMs is being increasingly reported, especially in young females. We present only the seventh such case reported in the literature and challenge the traditional view that all arteriovenous malformations are congenital in nature.