Cerebral venous thrombosis represents less than 5% of all strokes. Isolated cerebral deep venous thrombosis is very rare. We present a case of isolated thrombosis of the internal cerebral veins and the vein of Galen diagnosed on CT and MRI, and we review the literature. We emphasize the pathognomonic signs on CT and MRI necessary for an early diagnosis obviating conventional angiography. Early diagnosis and treatment may avoid potentially devastating consequences.