Visual and Structural Differences Between Amblyopic and Non-Amblyopic Eyes in Patients with Unilateral Amblyopia
DOI:
https://doi.org/10.51173/ijmhs.v2i1.27Keywords:
Amblyopia , Biometry , Axial Length , Lens Thickness , Visual AcuityAbstract
Background: Amblyopia, define as "lazy eye, a neurodevelopmental disorder, manifests as reduced visual acuity not attributable to structural eye abnormalities.
Objective of study: This study investigated visual and structural differences between amblyopic and non-amblyopic eyes in children with unilateral amblyopia, focusing on visual acuity, axial length, and lens thickness.
Materials and Methods: Twenty-six pediatric patients (5–10 years old) with untreated unilateral functional amblyopia were recruited. Amblyopia was classified as anisometropic, strabismic, or combined. Corrected distance visual acuity (CDVA) was measured in logMAR units. Axial length, anterior chamber depth, and lens thickness were assessed using non-contact optical biometry. Spherical equivalent refractive error was determined via cycloplegic autorefraction. Paired t-tests were used to compare interocular differences.
Results: Amblyopic eyes exhibited significantly reduced CDVA. However, no statistically significant interocular differences were found for spherical equivalent, axial length, anterior chamber depth, or lens thickness (all p > 0.05). Amblyopic eyes showed a trend towards shorter axial lengths (mean difference: -0.27 mm, SD: 0.72), particularly in anisometropic amblyopia (-0.21 mm, SD: 0.85). Anterior chamber depth and lens thickness showed minimal interocular variations across amblyopia types.
Conclusion: While amblyopic eyes demonstrated reduced visual acuity, interocular differences in biometric parameters were not statistically significant in this small sample. Trends suggest a potential association between amblyopia and shorter axial length, warranting further investigation with larger, longitudinal studies. This research contributes to understanding the ocular and cortical changes in amblyopia, aiming to refine treatment strategies and improve visual outcomes.
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