Prenatal diagnosis of an aneurysm of the vein of Galen with three-dimensional color power angiography

The prenatal diagnosis of an aneurysm of the vein of Galen has been reporte d on only a few occasions. This I rare arterio-venous fistula is suspected when an intracerebral hypoechoic cyst is found in which blood flow can be d emonstrated by Doppler ultrasound. This is one of the few conditions where Doppler ultrasound is critical for the diagnosis. Three-dimensional color p ower Doppler (3D-CPA) is a recent ultrasound modality which enables the thr ee-dimensional visualization of vessels and which is move readily available than magnetic resonance imaging (MRI) We report a fetus in which an aneury sm of the vein of Galen was detected at 33 weeks' gestation and where the a pplication of 3D-CPA enabled a better understanding of the spatial orientat ion and course of the dilated vessels. The neonate was successfully treated with coil angiography brit subsequently died at 5 months of age from cardi ac decompensation. Where fetal malformations involve the vascular system, 3 D-CPA appears to be a promising technique.