Treatment-induced changes in retinal thickness and ocular biometry in hyperopic anisometropic amblyopia: a prospective longitudinal study.

PURPOSE: To evaluate treatment-induced changes in retinal structural parameters and ocular biometric measurements in children with hyperopic anisometropic amblyopia following therapy. METHODS: This prospective longitudinal study included 30 children aged 5-7 years with newly diagnosed hyperopic anisometropic amblyopia (21 mild and 9 moderate) and 30 age-matched normal controls. All participants underwent comprehensive ocular examinations, including uncorrected and best-corrected distance visual acuity (BCVA), cycloplegic refraction, and axial length (AL) measurement using the ZEISS IOL Master 700. Additionally, subfoveal retinal thickness, retinal nerve fiber layer (RNFL) thickness, and macular parameters were assessed using spectral-domain optical coherence tomography. Following baseline examinations, patients received refractive correction for 2 months and were subsequently followed for 4 months after occlusion therapy. Ocular biometric and retinal structural parameters were compared before and after amblyopia treatment in amblyopic eyes, fellow eyes, and the right eyes of healthy children. RESULTS: Significant improvements in BCVA were observed in amblyopic eyes, improving from 0.21 ± 0.15 logMAR at baseline to 0.11 ± 0.16 logMAR after treatment (p < 0.001). Subfoveal retinal thickness decreased significantly only in amblyopic eyes, from 216.20 ± 19.36 μm to 210.76 ± 15.01 μm (p < 0.001), with no significant changes in fellow eyes (p = 0.097) or normal eyes (p = 0.099). Retinal nerve fiber layer (RNFL) thickness changes were significant only in fellow eyes, showing a reduction from 102.57 ± 9.31 μm to 101.10 ± 9.98 μm (p = 0.008), while amblyopic and normal eyes showed no significant changes (p > 0.05). Axial length (AL) increased significantly in all groups, but the increase in the fellow eyes (22.17±0.90 mm to 22.33 ± 0.89 mm, p < 0.001) was greater than that observed in amblyopic eyes (21.71±0.80 mm to 21.82 ± 0.86 mm, p < 0.001) or normal eyes (22.40±0.57 mm to 22.46 ± 0.59 mm, p < 0.001). Macular parameters and anterior chamber depth remained stable across all groups(p > 0.05). CONCLUSIONS: Structural retinal changes were observed in amblyopic eyes and in fellow eyes after patching, with no significant changes in normal eyes. Patching therapy may also lead to greater AL growth in the fellow eye compared to amblyopic or normal eyes.