CHARACTERIZATION OF MACULAR CHOROIDAL THICKNESS IN ISCHEMIC AND NONISCHEMIC DIABETIC MACULOPATHY

To evaluate changes in macular choroidal thickness in eyes with ischemic and nonischemic diabetic maculopathy.

Cross-sectional study of enhanced depth imaging optical coherence tomography of patients with diabetes. The diabetic eyes were divided into 3 groups: 1) eyes with no diabetic retinopathy (NDR); 2) those with diabetic retinopathy without macular ischemia (DR/MI-); and 3) those with diabetic retinopathy and macular ischemia (DR/MI+).

This analysis included 261 eyes of 160 patients. Eighty-eight eyes belonged to the NDR, 90 to the DR/MI-, and 83 to the DR/MI+ group. The choroidal thickness was significantly reduced in the DR/MI+ group as compared with the other 2 groups in the subfoveal region (NDR: 285.94 ± 80.38 μm, DR/MI-: 311.22 ± 94.55 μm, DR/MI+: 216.06 ± 58.41 μm; P < 0.001), nasally and temporally (P < 0.01). Between the NDR and DR/MI- groups, the choroidal thickness was significantly reduced nasally (P = 0.02) in the NDR group, but not subfoveally (P = 0.1) and temporally (P = 0.2). Notably, no statistically significant difference in central macular thickness was found between the DR/MI- (328.68 ± 103.28 μm) and DR/MI+ (341.99 ± 130.63 μm) groups (P = 1), although it was found to significantly increase in both these groups as compared with the NDR group (264.03 ± 27.74 μm; P < 0.001).

In diabetic maculopathy, an overall significant reduction was observed in macular choroidal thickness in eyes in ischemic stage as compared with nonischemic stage. In vivo evaluation of choroidal structural changes in the form of choroidal thickness may possibly be intuitive in understanding the pathogenesis of progression of diabetic maculopathy from nonischemic to ischemic stage, and associated functional damage.