Original Paper

Intraobserver Repeatability of Automated versus Adjusted Optical Coherence Tomography Measurements in Patients with Neovascular Age-Related Macular Degeneration
Sinan Tatlipinar^{a, c}, Syed Mahmood Shah^a, Peter A. Campochiaro^{a, b}, Quan Dong Nguyen<sup>a

a</sup>Retina Service, Wilmer Eye Institute, and
^bDepartment of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Md., USA;
^cDepartment of Ophthalmology, Pamukkale University School of Medicine, Denizli, Turkey

Address of Corresponding Author

Ophthalmologica 2007;221:227-232 (DOI: 10.1159/000101923)

  Key Words

• Neovascular age-related macular degeneration
• Optical coherence tomography
• Repeatability, automated vs. adjusted optical coherence tomography measurements

  Abstract

Aim: To assess the intraobserver repeatability of automated versusadjusted optical coherence tomography (OCT) measurements in patients with neovascular age-related macular degeneration (NVAMD). Methods: Ten eyes with NVAMD from 10 consecutive patients underwent two OCT measurements within 5 days by a single operator. Automated and adjusted central 1-mm foveal thickness and automated and adjusted total macular volume were measured in each study eye. The term 'adjusted' refers to manually corrected values, in which the interface landmarks for measurements are selected by the operator using Stratus® scan profiling and custom software. Bland-Altman method and bootstrap comparison of intraclass correlations (ICCs) were used for repeatability analysis. Results: Bland-Altman comparison did not reveal any statistically significant difference in any parameter, when results at first and second examination were compared (p > 0.05), indicating that the repeated measurements are similar. Further analysis was conducted using the bootstrap comparison of ICCs. The difference between adjusted and automated foveal thickness ICCs (r = 0.945 and 0.635, respectively) was significant (p = 0.031), indicating higher repeatability for adjusted foveal thickness. The ICCs for adjusted and automated total macular volume (r = 0.873 and 0.863, respectively) showed no statistically significant difference (p = 0.881). Conclusion: The repeatability of adjusted retinal thickness measurements, in which the errors of retinal boundary detection by OCT analysis software is corrected by the operator using scan profiling, is found to be higher than that of automated ones in this small group of NVAMD patients when performed by a single experienced operator.

Copyright © 2006 S. Karger AG, Basel

  Author Contacts

Quan Dong Nguyen, MD, MSc
Wilmer Eye Institute, Johns Hopkins Hospital
600 North Wolfe Street, Maumenee 721 Baltimore, MD 21287 (USA)
Tel. +1 410 502 5383, Fax +1 410 614 8577, E-Mail qnguyen4@jhmi.edu

  Article Information

This work was presented in part at the Annual Meeting of the Association for Research in Vision and Ophthalmology, Fort Lauderdale, Fla., USA, April 2005.

Received: July 27, 2006
Accepted: September 25, 2006
Number of Print Pages : 6
Number of Figures : 2, Number of Tables : 2, Number of References : 15