Abstract
Purpose: :
To compare macular thickness of the sound eye to that of the amblyopic eye using optical coherence tomography (OCT) in patients with myopic anisometropia. The associations between macular thickness, axial length and refractive error in the amblyopic eyes were also investigated.
Methods: :
24 subjects (17 females and 7 males) with a mean age of 10.6 yrs (5 to 25 yrs) were recruited. Macular thickness, A-scan, visual acuity, and cycloplegic refraction were measured on the amblyopic and sound eye. Macular thickness of both eyes was compared (paired t-test). Partial correlations were used to test the relationships among macular thickness, axial length and refractive error in amblyopic eyes while controlling for age and sex.
Results: :
Mean ± SD spherical equivalent in amblyopic eyes was -11.33 ± 3.16 diopters (D) with a range of -5.25 to -17.50 D and -2.10 ± 3.12 D in sound eyes. The mean magnitude of anisometropia was 9.23 ± 3.71 D, ranging from 3.63 to 17.50 D. Mean axial length was 26.87 ± 1.68 mm in amblyopic eyes and 23.46 ± 1.40 mm in sound eyes. Macular thickness is shown in Table 1. A significant difference in macular thickness was found between amblyopic and sound eyes. No correlation was found between macular thickness and axial length or macular thickness and refractive error in amblyopic eyes.
Conclusions: :
Histopathological studies have shown retinal thinning with myopia. Retinal involvement in amblyopia is controversial with some studies reporting a thicker macula in the amblyopic eye. We believe this is the first study to measure macular thickness in amblyopic eyes associated with myopia. Amblyopic eyes with high myopia had significantly thicker minimum and average foveas but thinner inner and outer maculae compared to sound eyes. Macular thickness in the amblyopic eyes was not related to axial length or refractive error.
Keywords: amblyopia • macula/fovea • myopia