[A case of superior sagittal sinus thrombosis following long-term medication with carbamazepine]

A 55-year-old man, who had been medicated with carbamazepine, phenobarbital, and sodium valproate for 12 years' duration, presented with severe headache, nausea, and transient diplopia. The neurological examination revealed mild disturbance of consciousness and postural tremor. He also complained of severe continuous headache but no throbbing pain. Enhanced head CT showed empty delta sign and irregular pooling of contrast agent around the superior sagittal sinus. Head MRI did not show the flow void in the superior sagittal sinus. Cerebral angiography demonstrated incomplete occlusion of the superior sagittal sinus and well-developed colateral channels. He was diagnosed having superior sagittal sinus thrombosis, and was placed on anticoagulant and antiplatelet drugs. He did not have any other risk factors such as inflammatory disease, infection, malignancy, and oral contraceptives. However, he had been medicated with some anticonvulsants including carbamazepine, which is known to induce venous thrombosis in the leg. Therefore, the association between superior sagittal sinus thrombosis and long term medication with carbamazepine was suspected. This is the first case report of anticonvulsant-associated cerebral venous thrombosis. It suggests that long-term medication with carbamazepine should be considered to be one of the risk factors for cerebral venous thrombosis.