Analysis of retinal nerve fiber layer and macular thickness measurements in healthy Taiwanese individuals using optical coherence tomography (Stratus OCT)

Purpose: To investigate the reproducibility of peripapillary retinal nerve fiber layer (RNFL) and macular thickness measurements in healthy Taiwanese subjects using optical coherence tomography (Stratus OCT). Methods: Fifty-two eyes of 52 healthy Taiwanese subjects (32 females and 20 males) were enrolled in the cross-sectional study. A randomly chosen single eye from each healthy subject underwent thickness measurements using OCT, before and after pupillary dilation, by 3 trained and experienced operators. Average measurements of peripapillary RNFL and macular thickness were calculated. Comparisons of thickness measurements before and after pupillary dilation, and among the 3 operators were performed. Results: The RNFL thickness measurements were higher in the inferior peripapillary area by RNFL scan (average: 107.4 17.8 mu m) and the macular thickness measurements showed a ring-shaped hump in the 3 mm perifoveal area by macular scan (average: 252.8 +/- 8.9 mu m). Comparing the peripapillary RNFL and macular thickness before and after papillary dilation, there was no significant difference (P > 0.05) in average, superior, inferior, temporal, or nasal peripapillary areas, in total macular volume and foveal thickness, nor in 1, 3, and 6-mm perifoveal areas, whether before or after pupillary dilation and irrespective of which operator performed the measurements. Conclusions: The inferior RNFL area and the 3-mm perifoveal area showed higher thickness measurements in the peripapillary region and macular region, respectively. The thickness measurements performed using OCT showed no significant differences before and after pupillary dilation, and showed good reproducibility.