Classification system proposed for eyes at high risk for rubeosis iridis

Classifying eyes of patients with internal carotid artery occlusion into four types may help clinicians more readily identify those at a high risk for rubeosis iridis, according to a Japanese study.

Takami Yamamoto, MD, and colleagues at the Kyoto Prefectural University of Medicine studied 34 eyes of 32 patients with complete internal carotid artery occlusion to evaluate the risk of rubeosis iridis. The researchers determined blood flow direction in the ophthalmic artery, central retinal artery and short posterior ciliary artery using color Doppler imaging.

The eyes were classified into four groups according to blood flow direction: forward in ophthalmic artery, central retinal artery and posterior ciliary artery (11 patients); reverse flow in ophthalmic artery and forward in the remaining two (12 patients); reverse flow in ophthalmic artery and undetectable flow in the others (eight patients) and undetectable flow in all three (three patients).

Rubeosis iridis was detected only in eyes with reverse and undetectable flows. Although the ophthalmic artery flow was in opposite directions in the first two groups, those eyes manifested no rubeosis iridis and no difference in the arterial mean blood velocity and resistive index of the central retinal artery and short posterior ciliary artery.

The study is published in the April issue of British Journal of Ophthalmology.