Objective To determine the repeatability of the optical characteristics of the retinal nerve fiber layer (RNFL) measured with optical coherence tomography (OCT) in healthy Chinese individuals. Methods In this cross-sectional study, 50 eyes of 50 normal subjects were consecutively recruited. RNFLs were imaged twice using a Cirrus OCT device with a 5-line raster macular scan and an optic disc cube mode in one day by a single operator. Customized software was used to measure RNFL optical characteristics, including optical density and the attenuation coefficient. Repeatability of OCT and customized software measurements were described by intraclass correlation coefficients (ICCs), coefficients of variation (COVs) and the Bland-Altman method. Results The mean and standard deviation of age were 51.2±8.1 years. The mean and standard deviations of macular RNFL thickness, optical density and the attenuation coefficient were 34.38±3.45 µm, 117.90±6.02 grey and 1.99±0.16, respectively. The mean and standard deviations of optic disc RNFL thickness, optical density and the attenuation coefficient were 89.07±3.19 µm, 138.10±18.25 grey and 3.48±0.64, respectively. All the evaluated RNFL parameters had good to excellent reproducibility. ICC ranged from 0.712 to 0.952 and COV ranged from 2.20% to 6.54%. The bias between two OCT measurements were -0.01 grey/0.33 grey and 0.01/-0.01, respectively, for macular and optic disc RNFL optical density and attenuation coefficients. Customized software showed excellent reproducibility in RNFL measurements. ICC ranged from 0.928 to 0.979 and COVs all bellowed 6%(1.35%-4.24%) for RNFL parameters measurement. Conclusion In our population of normal adult Chinese eyes, there is good repeatability of RNFL optic characteristics measured by OCT and customized software.
Shin JW, Uhm KB, Seong M. Retinal nerve fiber layer defect volume deviation analysis using spectral-domain optical coherence tomography[J]. Invest Ophthalmol Vis Sci,2014,56(1):21-28.
[5]
Din NM, Taylor SR, Isa H, et al. Evaluation of retinal nerve fiber layer thickness in eyes with hypertensive uveitis[J]. JAMA Ophthalmol,2014,132(7):859-865.
[6]
Takahashi M, Omodaka K, Maruyama K, et al. Simulated visual fields produced from macular RNFLT data in patients with glaucoma[J]. Curr Eye Res,2013,38(11):1133-1141.
[7]
Zhu BD, Li SM, Li H, et al. Retinal nerve fiber layer thickness in a population of 12-year-old children in central China measured by iVue-100 spectral-domain optical coherence tomography: the Anyang Childhood Eye Study[J]. Invest Ophthalmol Vis Sci,2013,54(13):8104-8111.
[8]
Chen X, Hou P, Jin C, et al. Quantitative analysis of retinal layer optical intensities on three-dimensional optical coherence tomography[J]. Invest Ophthalmol Vis Sci,2013,54(10):6846-6851.
[9]
Pons ME, Ishikawa H, Gürses-Ozden R, et al. Assessment of retinal nerve fiber layer internal reflectivity in eyes with and without glaucoma using optical coherence tomography[J]. Arch Ophthalmol,2000,118(8):1044-1047.
[10]
Vermeer KA, van der Schoot J, Lemij HG, et al. RPE-normalized RNFL attenuation coefficient maps derived from volumetric OCT imaging for glaucoma assessment[J]. Invest Ophthalmol Vis Sci, 2012,53(10):6102-6108.
[11]
Zheng C, Cheung CY, Narayanaswamy A, et al. Pupil dynamics in Chinese subjects with angle closure[J]. Graefes Arch Clin Exp Ophthalmol,2012,250(9):1353-1359.
[12]
Zheng C, Cheung CY, Aung T, et al. In vivo analysis of vectors involved in pupil constriction in Chinese subjects with angle closure[J]. Invest Ophthalmol Vis Sci,2012,53(11):6756-6762.
[13]
Zheng C, Guzman CP, Cheung CY, et al. Analysis of anterior segment dynamics using anterior segment optical coherence tomography before and after laser peripheral iridotomy[J]. JAMA Ophthalmol,2013,131(11):44-49.
[14]
Sng CC, Aquino MC, Liao J, et al. Pretreatment anterior segment imaging during acute primary angle closure: insights into angle closure mechanisms in the acute phase[J]. Ophthalmology,2014,121(1):119-125.
[15]
van der Schoot J, Vermeer KA, de Boer JF, et al. The effect of glaucoma on the optical attenuation coefficient of the retinal
nerve fiber layer in spectral domain optical coherence tomography images[J]. Invest Ophthalmol Vis Sci,2012,53(4):2424-2430.
[16]
Ludbrook J. Confidence in Altman-Bland plots: a critical review of the method of differences[J]. Clin Exp Pharmacol Physiol, 2010,37(2):143-149.
[17]
Wong AL, Leung CK, Weinreb RN, et al. Quantitative assessment of lens opacities with anterior segment optical coherence tomography[J]. Br J Ophthalmol,2009,93(1):61-65.
[18]
Fukuchi T, Takahashi K, Ida H, et al. Staging of idiopathic choroidal neovascularization by optical coherence tomography[J]. Graefes Arch Clin Exp Ophthalmol,2001,239(6):424-429.
[19]
Giani A, Esmaili DD, Luiselli C, et al. Displayed reflectivity of choroidal neovascular membranes by optical coherence tomography correlates with presence of leakage by fluorescein angiography[J]. Retina,2011,31(5):942-948.