Spontaneous Disappearance of Vein of Galen Malformation and Posterior Fossa Venous Pouch

Summary. Cerebrovascular anomalies remain an issue of controversy regarding diagnosis, classification, and treatment. We report the first case of total and asymptomatic regression and disappearance of a vein of Galen malformation associated with a posterior fossa venous pouch. Different aspects of the vein of Galen are discussed together with emphasis on the underlying mechanisms of spontaneous thrombosis and regression. A 4-month-old boy presented with macrocrania and signs of intracranial hypertension. Computerized tomography disclosed two masses, the first was a giant aneurysmal dilatation in the posterior fossa, and the second was a gigantic pouch at the level of the vein of Galen. Hydrocephalus was treated by ventriculo-peritoneal shunting. Two months later, the shunt was revised, and posterior fossa was explored without active treatment. Both abnormalities regressed spontaneously. No recurrence occurred, and the child remained neurologically intact. Total disappearance of the masses as well as normal brain and cerebrovascular anatomy were confirmed by angiography, MRI, and MRA. Over a follow-up period of 17 years, the patient did not develop complications. He had perfect clinical tolerance and resumed a normal life.