[Frequent attacks of amaurosis fugax due to hemodynamic mechanism based on severe stenosis of the internal carotid artery].

A 74 year-old man with prostate hypertrophy developed frequent attacks of amaurosis fugax in the left eye. Attacks only occurred in a standing position, but not when sitting or lying. He had taken tamsulosin hydrochloride for prostate hypertrophy and had orthostatic hypotension. After stopping the administration of tamsulosin hydrochloride and starting anthithorombotic theraphy, his orthostatic hypotension disappeared and the frequency of attacks decreased. Cerebral angiography demonstrated 95% stenosis and distal collapse of the left internal carotid artery (ICA), with collateral flow to the left middle cerebral artery from the right ICA through the anterior communicating artery. We thus postulated that a hemodynamic mechanism played an important role in the development of the amaurosis fugax which disappeared after carotid endarterectomy.