The correlation of macular and peripapillary retinal nerve fibre layer thickness in different grades of myopia

Background & Introduction; Myopia is a type of refractive error in which parallel rays coming from infinity are focused in front of retina with accommodation being at rest. In myopia there is elongation of eyeball leading to decrease in RNFL thickness. RNFL thinning is observed at high myopic powers. Glaucoma also causes decrease in RNFL thickness. Myopia being a risk factor for glaucoma may give us false positives. Therefore there is a need to evaluate the variation of RNFL thickness both at macula and peripapillary with different grades of myopia and get a baseline value for general population. Methodology: The peripapillary and macular retinal nerve fibre thickness was measured by Spectral Domain-OCT in different grades of myopes and compared with that of emmetrope to know the variations. Total no of 40 eyes were studied in each group. There were 04 groups divided on basis of spherical equivalent s follows: Result: 1. The peripapillary RNFL thickness in emmetropia, low myopia, moderate and high grade myopic eye were (95.15 + 5.47), (90.38 + 5.06), (82.08+ 13.11), (73.43+14.80) microns respectively. 2. The Central macular thickness in emmetropia, low myopia, moderate and high grade myopic eye were (225.25 +12.73), (226.98 + 21.83), (214.33+ 36.99), (213.08+ 45.48) microns Conclusion: There is decrease in average (Peripapillary) RNFL and Central Macular thickness with increase in grade of myopia.