Prenatal sonographic diagnosis of a vein of Galen aneurysmal malformation in a twin.

Arteriovenous malformations are the most common vascular congenital malformation of the brain. The vein of Galen arteriovenous malformation (VGAM) consists of end-to-end aneurysms in which the artery and vein connect without intervening capillaries. Cardiomegaly with congestive heart failure and increased intracranial pressure with hydrocephaly are the most common features in the neonate. In this case report, both features are present in utero. Prenatal morbidity and mortality are high due to cardiac failure. The authors present a case of spontaneous delivery at 35 weeks with one twin affected with vein of Galen aneurysm. [ABSTRACT FROM AUTHOR]