Retinal and Choroidal Vasculature Before and After Patch Occlusion Treatment Using Optical Coherence Tomography Angiography in Patients with Amblyopia

Abstract

This study aimed to investigate structural differences in the retinal and choroidal blood vessels before and after patch occlusion treatment in patients with amblyopia using optical coherence tomography angiography (OCTA) and to determine whether these differences are related to clinical improvement in patients. A total of 26 eyes of 17 patients with monocular or binocular amblyopia who underwent patch occlusion treatment for at least 1 month were retrospectively enrolled. The width of the foveal avascular zone, retinal blood vessel density, choroidal thickness, and choroidal vascularity index (CVI) measured by OCTA were compared before and after the treatment; the correlation with change in best-corrected visual acuity (BCVA) was analyzed for the data showing statistically significant differences. The mean BCVA of amblyopic eyes before and after patch occlusion treatment was 0.41 ± 0.23 and 0.25 ± 0.16 in logarithm of the minimum angle of resolution units, respectively. A decrease of about 2% in CVI was observed after the treatment (<i>p</i> = 0.011). The correlation between the changes in CVI and the changes in BCVA were insignificant (Rs = 0.086, <i>p</i> = 0.718). The results indicated that a decrease in CVI was observed after the patch occlusion treatment, but the relationship between CVI and BCVA could not be established. Patch occlusion treatment in amblyopia appears to affect the changes in the choroidal vessels and stroma.