Macular and retinal nerve fiber layer thickness in Japanese measured by Stratus optical coherence tomography

Toshiyuki Oshitari^1,2, Katsuhiro Hanawa¹, Emiko Adachi-Usami¹

¹Department of Ophthalmology, Center for Sensory Organ Diseases, Sannoh Medical Center, Chiba, Japan; ²Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Chiba, Japan

Abstract: The purpose of this study was to determine the thickness of the macula and the retinal nerve fiber layer (RNFL) in Japanese subjects by Stratus optical coherence tomography (OCT), and to compare the findings with the normative data of subjects from the United States of America (USA). Sixty-one eyes from 31 healthy subjects were used for the measurement of the macular thickness, and 60 eyes from 30 healthy subjects were used for the RNFL thickness measurements. The values obtained from the Japanese subjects were compared with the corresponding values in healthy subjects from the USA. The superior, nasal, temporal, and inferior macular sectors and the mean and inferior areas of the RNFL in the Japanese subjects were significantly thicker than the corresponding areas of normal subjects in the USA (272 ± 13 vs 255 ± 17 μm, 274 ± 12 vs 267 ± 16 μm, 262 ± 12 vs 251 ± 13 μm, 268 ± 13 vs 260 ± 15 μm; p < 0.0001, 104 ± 11 vs 100 ± 12 μm, 134 ± 20 vs. 126 ± 18 μm; p = 0.0167, 0.0047, respectively). In conclusion, the significantly thicker macular regions and RNFL in the Japanese indicate not only that there are racial differences in retinal thicknesses but also that the normative values provided by the Stratus OCT should not be used for different races.

Keywords: macular thickness, Japanese, normal, retinal nerve fiber layer, Stratus optical coherence tomography