Comparison of retinal nerve fibre layer thickness measurements calculated by the optic nerve head map (NHM4) and RNFL3.45 modes of spectral-domain optical coherence tomography (RTVue-100)
- Chul Jin Shin1,
- Kyung Rim Sung1,
- Tae Woong Um1,
- Yoon Jeon Kim1,
- Sung Yong Kang1,
- Jung Woo Cho1,
- Seong Bae Park2,
- Joo Ri Park1,
- Michael S Kook1
- 1Department of Ophthalmology, College of Medicine, University of Ulsan, Asan Medical Center, Seoul, Korea
- 2Departments of Ophthalmology, University of CHA, College of Medicine, Bundang CHA Medical Center, Sung Nam, Korea
- Correspondence to Professor Michael S Kook, Department of Ophthalmology, University of Ulsan, College of Medicine, Asan Medical Center, 388-1 Pungnap-2-dong, Songpa-gu, Seoul 138-736, Korea;
Contributors CJS data collection, analysis and interpretation, writing the article, critical revision of the article. KRS conception and design, data collection, analysis and interpretation, writing the article, critical revision of the article. TWU, YJK, SYK, JWC, SBP data collection, analysis and interpretation. JRP data collection. MSK conception and design, data collection, analysis and interpretation, writing the article, critical revision of the article.
- Accepted 29 December 2009
Aim To evaluate and compare retinal nerve fibre layer (RNFL) thickness measured by direct scanning (RNFL3.45 mode) and re-sampling from datasets (NHM4 mode) of RTVue-100 optical coherence tomography (OCT).
Methods Thirty-six healthy subjects and 76 subjects with glaucoma were imaged with Stratus OCT (fast RNFL mode, RNFL3) and RTVue-100 OCT (NHM4 (RNFL1) and RNFL3.45 (RNFL2) modes). Measurement reproducibility was assessed in NHM4 and RNFL3.45 modes of RTVue-100 OCT (intraclass correlation coefficient (ICC)). Agreement between different RNFL measurements was analysed by Bland–Altman plot. The areas under the receiver operating characteristic (ROC) curves (AUCs) for discrimination between healthy and glaucoma were compared between the different RNFL measurements.
Results Both NHM4 and RNFL3.45 modes showed excellent measurement reproducibilities (ICC 0.831–0.978). RNFL thicknesses by two different modes of the RTVue-100 OCT, and by the Stratus OCT, were correlated in all sectors, including average. There was no significant difference between RNFL1 and RNFL2 data. However, RNFL thickness in glaucomatous eyes by the RTVue-100 OCT was significantly greater than that measured by Stratus OCT. RNFL thicknesses determined by the two different modes of RTVue-100 OCT were in excellent agreement (95% limits of agreement −6.53 to 6.95 μm). All three RNFL measurements showed good glaucoma discrimination ability (AUC = RNFL1 0.970, RNFL2 0.962, RNFL3 0.971).
Conclusions RNFL thickness determined by direct scanning and re-sampling from datasets of RTVue-100 OCT were in good agreement. However, both measurements in glaucomatous subjects were significantly different from those with the Stratus OCT. Those findings should be considered when a patient is followed-up using different types of OCT.
Presented in part as a poster at the American Academy of Ophthalmology Annual Meeting, November 2008; Atlanta, Georgia, USA.
Competing interests None.
Patient consent Obtained.
Ethics approval This study was conducted with the approval of the Institutional Review Board of the Asan Medical Center at the University of Ulsan, Seoul, Korea. All procedures conformed to the Declaration of Helsinki.
Provenance and peer review Not commissioned; externally peer reviewed.