Periarteriolar-Sparing Retinal Edema in Acute Central Retinal Artery Occlusion

A 56-year-old man was referred to our hospital about 48 h after sudden onset of painless central visual loss in his right eye (OD) on a winter morning. He had a more than 25-year history of systemic hypertension and smoking. Funduscopic observation showed striated retinal whitening in the macular region, faint cotton-wool patches around the optic disc, and segmental narrowing of the retinal arteries near the optic disc edge. Based on the pattern of onset and fundus findings, he was diagnosed with vasospastic acute central retinal artery occlusion OD, and a venous drip injection of prostaglandin E1 was started immediately. Optical coherence tomography showed bands of high and low density in the inner retina arranged alternately in the edematous area; the bands corresponded to edematous and nonedematous areas, respectively, and geographically to venules and arterioles, respectively. The best-corrected visual acuity of 0.03 at referral improved to 0.5, and the striated retinal edema and most cotton-wool patches resolved 1 month after onset. The oxygen pressure gradient in the capillary networks due to differences in the distance from the arterioles may be the mechanism of this unique periarteriolar-sparing retinal edema pattern.