Indocyanine green angiography for identifying telangiectatic capillaries in diabetic macular edema

Abstract

AbstractAimsDuring diabetic macular edema (DME), a spectrum of capillary abnormalities is commonly observed, ranging from microaneurysms to large microvascular abnormalities. Clinical evidence suggests that targeted photocoagulation of large microvascular abnormalities may be beneficial, but their detection is not done in a routine fashion. It was reported that they are better identified by indocyanine green angiography (ICGA) than by fluorescein angiography. Here, we investigated the prevalence and ICGA and OCT features of large microvascular abnormalities in a group of patients with DME.MethodsObservational study. The fundus photographs, ICGA and structural and angiographic OCT charts of 35 eyes from 25 consecutive patients with DME were reviewed.ResultsTwenty‐two eyes (63%) had at least one focal area of microvascular abnormalities showing prolonged ICG staining (i.e. beyond 10 min after injection). In particular, all eyes with circinate hard exudates (n = 9) showed foci of late ICG staining in the center of exudates. These areas appeared either as isolated globular capillary ecstasies or as a cluster of ill‐defined capillary abnormalities. They were located at a median distance of 2708 µm from the fovea (range: 1064–4583 µm). Their diameter ranged from 153 to 307 µm. During ICGA, 94% of such large lesions showed an increase in their contrast and apparent size in late frames relative to early frames, while 77% of microaneurysms showed reduced contrast on late frames. OCTA appeared as poorly contributive for the detection of ICG stained lesions.ConclusionLate ICG staining revealing large microvascular abnormalities is commonly observed during DME. Because of their specific angiographic and OCT features relative to microaneurysms, we propose to name them telangiectatic capillaries.