Abstract
Purpose:
to compare the measurements of retinal and choroidal thickness with two non-contact optical biometers.
Methods:
Retinal and choroidal thickness were measured in right eyes of 32 young adult subjects by means of two non contact optical biometers (Heidelberg Spectralis OCT; Heidelberg Engineering and Lenstar LS900, Haag-Streit). For each subject, the average of 3 OCT measurements and 5 Lenstar measurements was analyzed. Comparison and inter-device agreement were evaluated using paired t-test and Bland-Altman plots.
Results:
Lenstar measurements were impossible to perform for retinal thickness (RT) in 15% of subjects; however all choroidal thickness (CT) measurements could be taken. The mean RT measured by OCT (213±14 μm) was systematically and significantly higher than when measured with Lenstar (183±20 μm), p<0.001. CT showed similar differences: 273±61 (OCT) μm and 203±38 μm (Lenstar), p<0.05. The mean inter-device differences in RT and CT were 31 μm and 75 μm respectively with 95% limits of agreement of [11 ; 50] μm and [-82 ; 232] μm.
Conclusions:
Agreement between OCT and Lenstar was poor for both retinal and choroidal thickness measurements. Retinal thickness could not be measured precisely in many subjects with Lenstar. For retinal and choroidal thickness studies, OCT seems to be a more appropriate choice than Lenstar.
Keywords: 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) •
452 choroid •
688 retina