Spontaneous thrombosis of an aneurysm of the great vein of Galen.

A case of a thrombosed aneurysm of the vein of Galen in a 9-year-old boy is reported. Previously, only ten clotted aneurysms of the vein of Galen have been described. In our case, thrombosis occurred spontaneously after birth. Clinical presentation was characterized by signs of hydrocephalus, with an abrupt deterioration after several years of satisfactory clinical evolution. The patient was successfully treated with a ventriculoperitoneal shunt.