A vein of Galen aneurysm with an abnormal drain system: MRI findings.

The case of a premature girl with a vein of Galen aneurysm is reported. The lesion was detected by ultrasonography. MRI provided complete anatomical information, obviating the need for initial angiography for preoperative evaluation of the malformation. Venous drainage through a persistent embryonic falcine sinus and associated atresia of the straight sinus could be identified, while venous thrombosis and parenchymal damage could be excluded.