Spectral-domain optical coherence tomography in subjects over 60 years of age, and its implications for designing clinical trials
- Albert Caramoy1,
- Jonathan Foerster1,
- Elvira Allakhiarova1,
- Carel B Hoyng2,
- Katharina Dröge1,
- Bernd Kirchhof1,
- Sascha Fauser1
- 1Department of Vitreo-Retinal Surgery, Center of Ophthalmology, University of Cologne, Cologne, Germany
- 2Department of Ophthalmology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
- Correspondence to Dr Albert Caramoy, Department of Vitreo-Retinal Surgery, Center of Ophthalmology, University of Cologne, Kerpener Strasse 62, Cologne 50924, Germany;
- Accepted 11 July 2012
- Published Online First 3 August 2012
Aims To study the variability of central retinal thickness (CRT), its concordance to the fellow eye, and the implications for designing future clinical trials using spectral-domain optical coherence tomography (SD-OCT).
Methods Cross-sectional retrospective analysis of European Genetic Database. 632 eyes of 316 subjects over 60 years of age without macular pathology were examined using SD-OCT.
Results Mean CRT was 280.22 µm and 281.02 µm for the right and left eyes, respectively. There was a strong concordance for all measured values between right and left eyes. Men had significantly thicker CRT than women. Variation up to 23 µm difference between both eyes was seen. To detect a change of at least 30 µm in CRT, a sample size of 90 or 176 per group is needed for a single-arm or double-arm study, respectively (α=0.05, power=0.80, no loss to follow up, assuming SD in future studies=100 µm).
Conclusions Clinical trials using CRT as an endpoint are feasible in terms of sample size needed.