Evaluation of macular thickness in myopic patients using optical coherence tomography

Abstract

Aim and Objective: To study correlation of macular thickness with degree of myopia using spectral domain optical coherence tomography (OCT). Materials and Methods: A prospective observational study on 159 eyes of 85 patients with axial myopia at Ophthalmology Department of tertiary care hospital for eighteen months. Axial length (AXL) of myopic patients between 18-30yrs age was calculated with a scan biomicroscope. These patients were subjected to OCT and macular thickness was calculated. SPSS version 23.0 was used for statistical analysis. AXL and macular thickness correlation was done using Pearson correlation test. Results: No significant difference in mean AXL in relation with age. Significant increase in AXL with increase in degree of myopia. Total macular thickness has no significance with increase in degree of myopia. Central foveal thickness significantly increased with increase in spherical equivalent (p<0.001). Average outer macular thickness decreased as degree of myopia increased with no statistical significance. For myopia between -0.25 to -2 D, the average outer macular thickness measured was 285.24 ± 9.66 µm, for myopia between -2.25 to -4 D it was 284.25 ± 9.06µm and for -4.25 to -6D it was 282.04 ± 4.64 µm. Correlation between AXL and central foveal thickness was positive and was statistically significant. Conclusions: Central foveal thickness increased with age and total macular thickness was greater in males. With progression of degree of myopia and increase in AXL, central foveal thickness increased, while retinal thickness of outer macular region decreased as assessed by OCT.