Vein of galen aneurysmal malformation with deep venous communication and subarachnoid hemorrhage.

A previously healthy 2-year-old boy presented with the acute onset of left middle cerebral artery syndrome. Evaluation revealed subarachnoid hemorrhage and a vein of Galen aneurysmal malformation with angiographic reflux into the deep venous system. Analysis of the angioarchitecture of the lesion demonstrated the basis of the hemorrhage to be reflux into cortical veins. The case supports and underscores the clinical relevance of recent reports indicating that the venous drainage of a vein of Galen aneurysmal malformation may communicate with the normal deep venous system. Such a communication implies that endovascular or surgical obliteration of the venous side of a vein of Galen aneurysmal malformation may impair normal venous drainage, potentially resulting in a venous infract or hemorrhage.