Macular Thickness among Different Refractive States (Emmetropia, Myopia, and Hypermetropia): An Optical Coherence Tomography-Based Comparative Study

Abstract

Background: Refractive errors are among the most common causes of visual impairment worldwide and may influence retinal morphology, particularly macular thickness. Optical Coherence Tomography (OCT) provides a reliable and non-invasive method for quantitative assessment of retinal architecture.

Objective: To compare macular thickness among emmetropic, myopic, and hypermetropic individuals using OCT and evaluate the association between refractive error severity and retinal thickness.

Methods: A hospital-based analytical study was conducted in the Department of Ophthalmology, Jawaharlal Nehru Medical College, Ajmer, Rajasthan, from June 2024 to May 2025. A total of 180 participants were enrolled and equally divided into emmetropic (n=60), myopic (n=60), and hypermetropic (n=60) groups. All subjects underwent visual acuity assessment, refraction, fundus examination, and OCT evaluation. Mean macular thickness and central retinal thickness were compared among groups.

Results: Mean macular thickness was significantly lower in myopic eyes (279 ± 8.17 µm) compared with emmetropic (291 ± 1.49 µm) and hypermetropic eyes (294 ± 1.49 µm) (p<0.001). Similarly, central retinal thickness was lowest in myopic eyes (235 ± 13.6 µm) compared with emmetropic and hypermetropic eyes (246 ± 3.0 µm and 246 ± 3.24 µm, respectively) (p<0.001). Increasing myopia was associated with progressive retinal thinning.

Conclusion: Refractive status significantly influences OCT-derived macular thickness measurements. Myopic eyes demonstrate reduced macular and central retinal thickness, while hypermetropic eyes tend to show relatively thicker retinal architecture. Consideration of refractive status is essential for accurate interpretation of OCT findings.