Central and Peripheral Visual Sensitivity Assessment in Low to Moderate Myopia

Document Type : Original Article

Authors

1 MSc in optometry, Department of optometry, Iran University of Medical Sciences, Tehran, Iran

2 Associate Professor, Department of Optometry, Iran University of Medical Sciences, Tehran, Iran

3 Professor of ophthalmology, Farabi Ophthalmology Research Center, Farabi Eye Hospital, Tehran, Iran

4 Assistant Professor, Department of Medical Surgical Nursing, School of Nursing and Midwifery, Shahid Beheshti University of Medical Sciences, Tehran, Iran

Abstract

Purpose:
The aim of the present study was to evaluate the correlation between peripheral and central visual sensitivity threshold and myopia in mild and moderate myopic eyes using Humphrey Field Analyzer (HFA).
Methods:
Twenty-nine subjects (58 eyes) with a mean refractive error of -2.98±1.2 D have undergone perimeric evaluation using peripheral 60-4 strategy in Humphrey device. The visual field was divided into three isopter rings: 30-40, 40-50 and 50-60 degrees. In each ring, the mean threshold was compared between the two myopic groups. Foveal thresholds were also measured and compared between groups.
Results:
In comparison between the mild and moderate myopic groups, there were not any significant differences in 30-40 ring (p=0.42), 40-50 ring (p=0.45) and 50-60 ring (p=0.35). However, a significant but negative correlation was found between foveal threshold and myopia (r=-0.33, p=0.01)
Conclusion:
Lack of any correlation between myopia and peripheral sensitivity threshold demonstrates that peripheral visual field is not a variable parameter in myopia studies. Further studies and in larger scales are recommended.

Keywords

Main Subjects


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