Measurement of Normal Macular Thickness Using Cirrus Optical Coherence Tomography Instrument in Iranian Subjects with Normal Ocular Condition

Purpose: To describe the macular thickness map of Iranian adult with normal retinal status as measured by Cirrus’ optical coherence tomography (OCT) instrument Methods: In this cross-sectional study, one eye of subjects with normal ocular examination and retinal status of at least one eye were recruited. The 512×128-scan pattern and scan area of 6×6 mm2 with software version 4 protocol in Cirrus OCT apparatus were used for data acquisition and analysis. Results: A total of 98 individuals participated in this study. 45.9% of the participants (i.e., 45 subjects) were male. The mean age of the subjects was 49.55±16.31 years; ranging from 23 to 80 years. The mean central subfield thickness (CST) was 251.39±20.57 μm which is the thinnest part. The mean CST in men and women were 259.33±21.26 μm and 244.64±17.48 μm, respectively (p<0.001). The thickest part of macula was located in the foveonasal area with a measurement of 320.2±14.54 μm. There was not any significant correlation among age (p=0.207), gender (p=0.290), and the CST. The nasal, superior, inferior, and temporal parts of macula, consecutively, exhibited a decrease in macular thickness. The mean macular volume was 9.95±0.49 mm3 (i.e., 10.05±0.54 mm3 in men and 9.86±0.41 mm3 in women, respectively). There is, however, a statistically-significant correlation between age and the macular volume (p<0.001). With every one year increase in age, there was a 0.012 mm3 decrease in macular volume. The average retinal thickness was 277.58±11.55 μm. Additionally, there is a significant correlation between age and average thickness (p<0.001) from statistical point of view. With every one year increase in the age, there was a 0.266 μm decrease in the average thickness. Conclusion: The thickest part of the macula was located in the foveonasal area with a measurement of 320 μm while the thinnest part was in the central subfield area with a measurement of 251 μm. The nasal, superior, inferior, and temporal parts of macula, consecutively, exhibited a decrease in macular thickness. In younger adults and among males, the mean thickness was greater.