Effect of Myopic Anisometropia On Contrast Sensitivity

Abstract

Objective: The objective of this study is to evaluate the “Effect of Myopic Anisometropia on Contrast Sensitivity.”
Methods: The duration of this Cross-sectional investigation was four months. Data was collected from Al-Mustafa Mozang Eye Hospital, the University of Lahore Teaching Hospital, and LRBT Hospital Lahore between November 2024 and January 2025. Sixty (n=60) myopic anisometropic patients ranging in age from 10 to 35, were involved in this study. Objective refraction was accomplished with Auto Refractometer (Axis tsrk 1000P), and vision was examined with Snellen LED Visual Acuity Chart (model 18.5). Measured contrast Sensitivity by the Pelli-Robson Chart using Smart Optometry app. SPSS version 27.0 was used to analyze the results.
Results: The study included 60 participants, comprising 29 males (48.3%) and 31 females (51.7%), aged between 10 and 35 years. Participants were evenly categorized into mild, moderate, and high myopic anisometropia groups, each consisting of 20 individuals (33.3%). The Kruskal-Wallis test for OD revealed a statistically significant difference (p=0.004), with the mild group having the highest mean rank (37.50) and contrast sensitivity (2.0425, SD= ±0.12067). For OS, a significant difference was also found (p<0.001), where moderate anisometropia had the highest mean rank (34.70) and high anisometropia the lowest (20.80). However, for OU no statistically significant difference was observed when all groups had equal mean ranks (30.50) and contrast sensitivity values (2.10, SD=±0.00, p=1.00).
Conclusion: Contrast sensitivity is affected in cases of high-degree and moderate degree myopic anisometropia when measured uniocular. However, when assessed binocularly, myopic anisometropia has no significant effect on contrast sensitivity.