De Novo Intracranial Arteriovenous Malformation-Case Report and Literature Review.

Background: Intracranial arteriovenous malformations (AVMs) have been considered congenital. We present and discuss a case of a child who had no evidence of an AVM at 6 years of age when presenting with parenchymatous hemorrhage due to cavernous angioma and who developed the lesion during 10 years of follow-up.

Case Description: A 6-year-old female presented with parenchymatous hemorrhage and was diagnosed with cavernous angioma of the right occipital lobe. She was treated with lesion removal and remained asymptomatic during the initial follow-up. At age 16, she presented to the emergency department with a new-onset headache. A new magnetic resonance imaging scan was performed and revealed an AVM in the right temporal lobe, which was confirmed with digital subtraction angiography. The AVM had not been present 10 years earlier, as seen on the previous digital subtraction angiography and magnetic resonance imaging examinations.

Conclusions: On the basis of recent findings of de novo AVMs and on the current theory of a postnatal origin of AVMs, we propose that AVMs cannot always be considered congenital and that several factors can contribute to their pathogenesis.