Assessment of Macula and Retinal Nerve Fiber Layer Thickness with Optical Coherence Tomography in Myopia

Objective: In the study, analysis of retina structure with optical coherence tomography (OCT) in emetropic and myopic cases was aimed. Material and Methods: The study group included a total of 224 cases (118 females, 106 males). Cases were divided into four groups: between 0.00/-0.75 D (first group=control group), between -1.00/-3.00 D (second group), between -3.25/-6.00 D (third group) and between -6.25/-12.00 D, according to their refractive error. Thickness of retinal nerve fiber layer (RNFL) and macula was measured using OCT. Results: While an increase was detected in foveal thickness and volume in the highly myopic group, a reduction was found in RNFL thickness of all areas except temporal area. Total macular volume, outer macular thickness and volume were also reduced. The highest thinning of RNFL in highly myopic cases was in 13.1% in superior and 18.6% in nasal thickness. There was a weak correlation between RNFL thickness, macular thickness and volume values and axial length/spheric equivalent. Conclusion: Assessment of especially nasal and superior quadrant thickness in RNFL is crucial in highly myopics. Distance between foveal pit and parafoveolar tip is inversely proportional with myopia, in other words, increase in degree of myopia causes macular area to become flatter.