PT - JOURNAL ARTICLE AU - Krebs, Ilse AU - Hagen, Stefan AU - Smretschnig, Eva AU - Womastek, Irene AU - Brannath, Werner AU - Binder, Susanne TI - Conversion of Stratus optical coherence tomography (OCT) retinal thickness to Cirrus OCT values in age-related macular degeneration AID - 10.1136/bjo.2010.194670 DP - 2011 Nov 01 TA - British Journal of Ophthalmology PG - 1552--1554 VI - 95 IP - 11 4099 - http://bjo.bmj.com/content/95/11/1552.short 4100 - http://bjo.bmj.com/content/95/11/1552.full SO - Br J Ophthalmol2011 Nov 01; 95 AB - Aim Spectral domain optical coherence tomography (SD OCT) is of increasing importance and is gradually replacing time domain OCT (TD OCT). Our aim was to determine a formula to convert Stratus OCT (TD OCT) to Cirrus OCT (SD OCT) retinal thickness.Methods Central retinal thickness (CRT) and retinal volume (RV) were obtained by the macular thickness program of Stratus OCT and the cube 512×128 program of Cirrus OCT in patients with exudative age-related macular degeneration (AMD). Algorithm line failures were corrected. A linear model with Stratus OCT CRT as fixed factor and Cirrus OCT CRT as dependent variable was applied to calculate the conversion formula.Results OCT examinations of 104 eyes of 104 patients were reviewed and corrected when necessary. Stratus and Cirrus OCT CRT were significantly correlated (p<0.0001). For CRT the formula Cirrus CRT=58.63+0.94× Stratus CRT was calculated. The correlation was significantly influenced by the height of the CRT values (p<0.0001), but not by whether correction was necessary. For RV the formula Cirrus OCT RV=3.098+0.98× Stratus OCT RV was calculated.Conclusion Stratus OCT and Cirrus OCT use a different posterior reference line within the hyper-reflective band of the outer retina. Therefore a conversion formula is necessary to compare Stratus and Cirrus OCT CRT values, and this has been determined in our study.