Of 123 patients undergoing cerebral angiography for evaluation of transient ischemic attacks, 23 (19%) were found to have occlusion of one or both internal carotid arteries. In 15 patients the symptoms were well-localized to the hemisphere supplied by the occluded carotid artery. The majority of these patients defied clinical diagnosis prior to angiography despite the usual tests for cerebral vascular insufficiency. The Doppler ophthalmic test gives indications of being, perhaps, the most reliable screening examination for internal carotid artery occlusion.
Herbert I. Machleder, Wiley F. Barker. Stroke on the Wrong SideUse of the Doppler Ophthalmic Test in Cerebral Vascular Screening. Arch Surg. 1972;105(6):943–947. doi:10.1001/archsurg.1972.04180120118021