Abstract

Subarachnoid hemorrhage (SAH) w hich usually presented with the thunderclap headache is the disease that has significant m ortality. Therefore, the diagnosis of SAH deserves special emphasis. A 69-year-old female visited at the emergency room due to the headache. In the brain CT only ischemic change w as revealed. H owever, dark signals in the sulci on the temporo-parietal lobe w ere shown in the GRE of brain M RI. A dissecting aneurysm of the posterior cerebral artery w as detected on the digital subtraction angiography. If the patient presented w ith the thunderclap headache, a further evaluation should be proceeded in view of the fact that the dark signals of GRE can be an acute subarachnoid hemorrhage.