Comparison of White-to-White Diameters Measured by IOLMaster, Lenstar, Orbscan, and a Manual Method

ABSTRACT

PURPOSE: To compare and evaluate device efficacy using white-to-white (WTW) diameter measurements by IOLMaster(R), Lenstar(R), Orbscan II(R), and a manual method with anterior segment photographs in normal eyes. METHODS: Three sets of WTW diameter measurements were obtained from 62 normal eyes of 31 patients, using the Orbscan II(R), Lenstar(R), IOLMaster(R), and a manual method with anterior segment photographs. Repeatability of each device was evaluated by coefficient of variation. ANOVA and Pearson's correlation were used to compare the differences among the devices. Bland Altman plot was performed to assess measurement agreement among the devices. RESULTS: The mean WTW distance was 11.79 +/- 0.46 mm with Orbscan II(R), 12.05 +/- 0.38 mm with Lenstar(R), 12.15 +/- 0.36 mm with IOLMaster(R), and 12.30 +/- 0.40 mm with a manual method. There were significant differences in the results among the methods (ANOVA, p 0.8, p < 0.05). The coefficient of variation of Orbscan II(R) was larger than those of Lenstar(R) and IOLMaster(R). CONCLUSIONS: The WTW measurement using Orbscan II(R) has low correlations with other devices and lower repeatability. Our findings suggest that partial coherence interferometry should be considered as a new standard.