Assessment of Macular Thickness in Different Grades of Myopia: An Optical Coherence Tomography Study in a Rural Tertiary Care Hospital

Abstract

Abstract Background: Myopia is a condition related to the refractive error that causes visual disability. Due to its high prevalence, it can contribute to complicated cataracts and related conditions such as primary open-angle glaucoma. The risks of retinal detachment, chorioretinal atrophy, pigmentary degeneration, vitreous degeneration and retinal breaks may increase with an increase in axial length and severity of myopia, among other long-term effects of high myopia. The aim of this study was to assess the role of macular thickness and myopia in non-invasive optical coherence tomography (OCT). Materials and Methods: This was a prospective, hospital-based observational study conducted for 18 months in a tertiary care centre in Karnataka. A total of 155 consecutive myopia patients aged ≥10 years attending the outpatient Department of Ophthalmology were included in the study. The data were analysed using the Statistical Package for Social Sciences (SPSS) for Windows, version 22.0 (SPSS Inc., Chicago). Result: The participants aged from 10 to 75 years with a female preponderance of 60%. The mean age of participants is 31.95 yrs. The majority of the patients had mild myopia (91.6%), compared with moderate (5.8%) and high (2.6%) myopia. The mean value of best-corrected visual acuity improved from 0.67 to 0.08 in high, 0.94 to 0.22 in mild and 0.71 to 0.26 in moderate myopia patients. The mean maximum retinal thickness was 472 micrometres, and the mean minimum retinal thickness was 178 micrometres. Conclusion: There is a high prevalence of mild myopia cases, especially at extremes of age. Myopia was more common among females. There was a significant difference among different classes of myopia with respect to uncorrected and best-corrected visual acuity. The parafovea was thinner and the fovea thicker among myopia.