A traveling "spot sign" in recurrent amaurosis fugax and central retinal artery occlusion.

Sudden monocular blindness is frequently caused by central retinal artery occlusion (CRAO) from embolic sources. Treatment options are insufficient, and spontaneous prognosis toward visual recovery is poor. In addition to ophthalmologic evaluation, transorbital sonographic assessment of the central retinal artery may help establish early diagnosis by Doppler sonographic proof of occlusion and, in some cases, by B-mode detection of an intra-arterial "spot sign". We report the case of a patient with recurrent amaurosis fugax and subsequent CRAO. Ultrasound examination after 2 incidences of amaurosis fugax demonstrated a patent but stenotic central retinal artery, with stenosis caused by an embolus visualized as a "spot sign". The following day, persisting amaurosis suddenly developed. Sonographic re-evaluation revealed downstream dislodgment of the "spot sign" and complete arterial occlusion. Thrombolytic treatment did not result in clinical improvement. In conclusion, this case report describes a single case of repeated amaurosis fugax and deterioration to CRAO via embolization into the central retinal artery and consecutive downstream dislodgment. It emphasizes that ultrasound may render valuable diagnostic information in patients with acute central retinal artery embolization toward its embolic etiology and its risk of subsequent deterioration.