DETERMINATION OF FACTORS ASSOCIATED WITH PERIPAPILLARY RETINAL NERVE FIBER LAYER AND MACULAR THICKNESS USING OPTICAL COHERENCE TOMOGRAPHy

Retinal nerve fiber layer thickness is an important factor in the early diagnosis of
posterior pole dysfunctions, assessment of treatment effect, and disease progression. The aim of this
study was to compare the macular and peripapillary retinal thickness between genders and among
refractive error types in healthy subjects. In addition, effective determinants of the thickness were
ascertained.
Materials & Methods: This cross-sectional study was conducted on 58 subjects (116 eyes) who were
referred to the Toos eye clinic of Mashhad, northeast of Iran, for refractive error surgery and their
caregivers in 2014. We used Optical Coherence Tomography for retinal thickness measurements.
Results: The mean age was 26.02±0.42 years. The mean±SD spherical equivalence was estimated to be
-2.06 ± 0.36 dioptres, axial length was 23.89 ± 0.14 mm, average peripapillary thickness was 89.91 ±
0.94 μm, average macular thickness was 274.68 ± 1.84 μm, and overall macular volume was 9.89 ± 0.07
mm3. Multiple linear regression modeling indicated that axial length and gender had a significant effect
on average macular thickness. Axial length also showed a substantial effect on average peripapillary
thickness.
Conclusion: Retinal thickness measurement regardless of refractive error type could lead to bias in
disease diagnosis. The results of the present study might be used to enhance the assessment precision of
ocular diseases