Aplasia cutis congenita and arteriovenous fistula. Case report and review. We describe a child with congenital aplasia cutis congenita of the scalp and an occult giant posterior fossa arteriovenous fistula. Previous case reports of central nervous system malformations associated with aplasia cutis congenita are reviewed. The exact incidence of such malformations is unknown. All patients with aplasia cutis congenita should undergo a neurologic evaluation, and their families should be examined for similar lesions. Early central nervous system imaging and other workup may be required, especially if plastic surgery in the head region is being planned. 