Intersession repeatability of optical coherence tomography measures of retinal thickness in early age-related macular degeneration
Article first published online: 21 OCT 2009
© 2009 The Authors. Journal compilation © 2009 Acta Ophthalmol
Volume 89, Issue 3, pages 229–234, May 2011
How to Cite
Patel, P. J., Chen, F. K., Ikeji, F. and Tufail, A. (2011), Intersession repeatability of optical coherence tomography measures of retinal thickness in early age-related macular degeneration. Acta Ophthalmologica, 89: 229–234. doi: 10.1111/j.1755-3768.2009.01659.x
- Issue published online: 21 OCT 2009
- Article first published online: 21 OCT 2009
- Received on December 29th, 2008. Accepted on April 21st, 2009.
- age-related macular degeneration;
- clinical methods;
- optical coherence tomography;
- reproducibility of results
Purpose: To determine the intersession repeatability of Stratus optical coherence tomography (OCT) measures of retinal thickness in patients with age-related macular degeneration (AMD).
Methods: Measurement of retinal thickness was performed over four sessions over 12 weeks using a standardized OCT protocol with the fast macular thickness map in 67 non-treated eyes of 67 patients with AMD enrolled in a clinical trial. The intrapatient standard deviation (Sw) and 95% coefficient of repeatability (CR) (), expressed in μm and as a percentage of mean retinal thickness, were calculated to estimate intersession repeatability.
Results: The CR was 32 μm for the average retinal thickness in the central 1 mm A1 subfield [95% confidence interval (CI) 31–33 μm] and 53 μm (95% CI 51–55 μm) for the centre-point thickness (CPT). When expressed as a percentage, the CR was 15% (95% CI 14–16) for the central 1 mm A1 subfield and 29% (95% CI 27–30) for the CPT measure.
Conclusion: The average central 1 mm (A1) subfield retinal thickness measure shows good intersession repeatability in patients with stable, early AMD with poorer repeatability for the CPT measure. The results suggest that a change in Stratus OCT retinal thickness of more than 32 μm in the central A1 subfield is more indicative of true clinical change in these patients.