Choroid changes in amblyopic, fellow and control eyes
Reviewed by Fiona Rowe

In this study the authors aimed to evaluate choroidal changes in the hyperopic anisometropic eyes of children by comparing amblyopic and fellow eyes, and control eyes, using a binarization method – analysis of enhanced depth imaging with OCT (EDI-OCT) using open access Image J software (NIH). This provides objective imaging of vascular and stromal areas of the choroid. This was a retrospective study of 30 patients; 14 males and 16 females, and 30 controls; 16 males and 14 females. Mean age was 10.67 ±3.67 years for amblyopes and 10.30 ±4.15 years for controls. Mean spherical equivalent refraction was 3.75 ±2.16D for amblyopic eyes, 2.30 ±2.09D for fellow eyes and -0.27 ±0.53D for control eyes. Mean best corrected visual acuity was 0.29 ±0.11logMAR for amblyopic eyes, 0.02 ±0.04 for fellow eyes and 0.00 ±0.00 for control eyes. Mean choroidal thickness was 351 ±47um for amblyopic eyes, 333 ±55 for fellow eyes and 324 ±51 for control eyes. Mean choroidal vascular index was 63 ±0.02% for amblyopic eyes, 64 ±0.02 for fellow eyes and 66 ±0.03% for control eyes. All were significantly different between eye groups. Past studies conclude the choroidal layer is thicker in eyes with amblyopia and confirmed in this study. The potential mechanism is that myopic defocus may underpin this. The amblyopic eye choroid was significantly thicker than fellow and control eyes. The fellow eye choroid thickness was also thicker than control eyes, but this is not significant. Choroid vascular index was lower for amblyopic and fellow eyes compared to controls. Therefore, fellow eyes have some anatomical effect from amblyopia, even if not functional.

Features of the choroidal structure in children with anisometropic amblyopia.
Alis MG, Alis A.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2022;59(5):320-5.