Assessment of choroidal thickness and macular microvascular changes in amblyopic eyes using optical coherence tomography angiography

Abstract

Aim This study aimed to assess microvascular and choroidal thickness (CT) changes in cases with unilateral amblyopia and to compare optical coherence tomography angiography parameters with the fellow eyes as well as with age-matched controls. Study design This is a prospective case–control study. Patients and methods The study included 44 eyes; 12 eyes had unilateral anisometropic amblyopia compared with their fellow 12 eyes and 20 eyes from normal age-matched controls. Spectral-domain optical coherence tomography angiography was used to assess the vessel density (VD) of the superficial capillary plexus (SCP) and the deep capillary plexus (DCP) in both 3×3 and 6×6 mm scans. In addition, central macular thickness, foveal avascular zone size, and CT were measured. Results The mean age of amblyopic patients was 25.1±10.8 years with a mean BMI of 22.4±4.7 compared with the mean age of the control group (26.4±2.8 years) with a mean BMI of 21.0±2.1. Amblyopic eyes showed a statistically nonsignificant decrease in subfoveal CT (mean=328.58±34.46 μm) and temporal CT (mean=318.42±33.93 μm) compared with their fellow eyes (321.00±42.41 and 317.33±57.21 μm, respectively) and with the control eyes (subfoveal CT 349.80±72.33 μm and temporal CT 346.50±40.61 μm, P=0.178 and 0.177, respectively). There was a significantly decreased VD in the SCP of amblyopic eyes at the 3 mm scan (P=0.032) with a mean of 43.87±4.67% in the whole image. In addition, DCP VD in the 6 mm scan showed a statistically significant decrease (mean=43.91±7.26%) compared with the fellow and control eyes (P=0.001). The foveal avascular zone size was almost the same in all groups (0.28±0.13 mm2) with no significant difference. Conclusion Amblyopic eyes showed decreased VD in both SCP and DCP compared with that of the fellow eyes and controls.