Nonimmune hydrops fetalis, hydramnios, microcephaly, and intracranial meningeal hemangioendothelioma

Necropsy findings in a male stillborn at 31 weeks gestational age included nonimmune hydrops, hydramnios, and microcephaly secondary to a hemangioendotheliomatous malformation at the tentorium. The vascular lesion was composed by large and small tortuous endothelium-lined vessels and leiomuscular septa. The lesion is thought to be related to the more frequent arteriovenous malformation of the vein of Galen.