Comparison the property of new instruments to the IOL-master 500 on patients with cataract

Abstract

Abstract Objectives To assess the consistency and difference on six new instruments to IOL-master 500 through evaluating the corneal power measurements. Materials and methods 88 eyes of 88 subjects were included from Oct. 2018 to Apr. 2019 in this study. The keratometric data, magnitude of astigmatism and astigmatism axis were measured by IOLmaster 500 (Zeiss), Lenstar LS-900 (Haag-Streit), Pentacam HR (Oculus), iTrace (Tracey Technology), Verion(Alcon), Atlas 995 corneal topography (Zeiss), KR-800 auto-refractometer (Topcon), respectively. Blant-Altman analysis plots were used to evaluate the conformity of corneal curvature between these instruments, and the differences of corneal curvature were compared by one-way analysis of variance (ANOVA). Double-angle plots were used to describe the difference on astigmatism assessment. Results The mean age of all subjects was 35.86±10.27 years, and the male/female ratio was 34/54. There was no significant difference of corneal curvature in all the instruments, LoA range of each instrument compared with IOL-master 500 using Bland-Altman plots were - 0.14D～0.33D、- 0.05D～0.62D、- 1.5D～2.0D、- 0.93D～0.44D、- 0.39D～1.10D、- 0.39D～0.59D , respectively. The widest length is produced by the iTrace (-1.5D-2.0D), and the narrowest length is the Lenstar LS 900 (-0.14D-0.33D), when compared to IOL-master. Moreover, the astigmatism errors of the instruments compared with IOL-master 500 using Double-Angle plots were 0.09D×78°±0.33D, 0.08D×69°±0.40D, 0.12D×80°±0.36D, 0.09D×13°±0.41D, 0.37D×77°±0.68D, 0.14D×86°±0.39D, respectively. The maximum and minimum against-the-rule (ATR) compared to the IOL-master are Atlas 995 corneal topography and Pentacam, respectively. Conclusions These instruments showed good agreements in evaluating corneal curvature, and Pentacam is a promising choice to detect the astigmatism size and direction based on the minimum error compared with IOL-master.