Posterior fossa subdural hematoma demonstrated by vertebral angiography

A case of spontaneous posterior fossa subdural hematoma secondary to anticoagulation therapy with definitive diagnosis made by vertebral angiography is reported. Vertebral angiographic findings are illustrated and demonstrate primarily mass effect from posterior compartment of posterior fossa and avascular area. Carotid angiography did not show hydrocephalus. A review of the literature was made and this appears to be the first reported case in which a posterior fossa subdural hematoma has been diagnosed by vertebral angiography.