A case of subarachnoid hemorrhage presenting with temporary blindness disclosed by Xe CT-CBF study

A 69-year-old male with right oculomotor palsy caused by non-ruptured right internal carotid-posterior communicating artery aneurysm suddenly became blind after cerebral angiography. He lost consensual response of left eye, in spite of no preretinal hemorrhage. Xenon computed tomography(Xe-CT) showed moderate cerebral blood flow(CBF) decrease of bilateral posterior cerebral artery territories at the values of 26.9 ml/100 g/min(left) and 28.3 ml/100 g/min(right), which were about 30% under our control value. However, MR T2-weighted imaging demonstrated no cerebral infarction. Two weeks later, regional CBF values were improved and 6 months later his visual acuity were almost cured. We conclude that Xe-CT CBF study supports the hypothesis of the temporary blindness due to the optic chiasm and nerves injuries by subarachnoid hemorrhage.