Partial Central Retinal Artery Occlusion: An Underrecognized Entity

BACKGROUND: The objective of this publication is to report a case of an atypical partial central retinal artery occlusion (CRAO) with substantial visual recovery without treatment. CASE PRESENTATION: An 83-year-old woman without significant medical history with sudden unilateral visual loss presented with no known significant ophthalmological or medical history besides systemic arterial hypertension. Examination showed multiple cotton-wool spots in a peripapillary distribution, as well as a heterogenous pattern of grey translucency in the macula resulting in an indistinct cherry-red spot. Fluorescein angiography showed normal choroidal filling and an important delay of dye transit through the retinal circulation. Carotid Doppler echography showed a small endothelial atherosclerotic plaque without hemodynamic repercussion. A detailed history and further examination revealed no other systemic diseases except for moderate hypercholesterolemia. The patient was referred for management of her hypertension but otherwise did not undergo specific therapy for CRAO because of the delayed presentation. Four weeks after the initial visual loss, the patient showed resolution of the retinal findings and a surprising improvement to 20/50 visual acuity. CONCLUSION: This case highlights a rare subtype of central retinal artery occlusion. In this disease, partial occlusion reveals atypical signs including large cotton-wool spots as the predominant finding, making the initial diagnosis difficult. Visual recovery may be significant in partial CRAO, even without treatment.