AIM: To compare the detection rate of axial length(AL)in cataract eyes by Tomey OA-2000 and IOL Master 500, and to evaluate the repeatability of OA-2000 in measuring ocular biometrics parameters.

METHODS: A cross-sectional study of 270 cataract eyes was implemented in the ophthalmic outpatient department from July to September 2018. Ocular biometric measurements including AL, keratometry readings(K), anterior chamber depth(ACD), lens thickness(LT), central corneal thickness(CCT), pupil diameter(PD)and white to white(WTW)were performed using OA-2000 and IOL Master 500. The detection rates of AL were calculated and compared between the two devices.

RESULTS: AL detection rates of 86.3%(233/270)and 97.0%(262/270)were found by IOL Master 500 and OA-2000 respectively. The mean difference in the measured AL by the two devices was(0.007±0.129)mm, and the 95% limits of agreement(95%LoA)of AL was 0.01(-0.24 to 0.26)mm. OA-2000 demonstrated good repeatability in measuring AL, ACD, K(2.5mm and 3mm pupil diameter), LT and CCT, but not in measuring PD and WTW.

CONCLUSION: Both OA-2000 and IOL Master 500 showed good agreement in AL measurement in cataract patients. However, compared with IOL Master 500, OA-2000 has a higher detection rate of AL. OA-2000 not only demonstrates excellent repeatability in ocular biometric measurements including AL, ACD, K, LT and CCT, but also more advantageous for the AL measurement of cataract with heavy lens opacity and subcapsular opacity.