AIM: To evaluate the repeatability of a swept-source optical coherence tomography(SS-OCT)based biometer-IOL Master 700 in ocular biometrics in cataract eyes, and to investigate its agreement with a partially coherent optical interference based biometer-IOL Master 500. This study was also designed to compare the detection rate of the axial length(AL)measured by the two biometers.

METHODS:A total of 225 eyes of 133 cataract patients were included in this cross-sectional study from July to September 2018. Ocular biometric parameters including AL, keratometry(K), anterior chamber depth(ACD), lens thickness(LT), central corneal thickness(CCT)and white to white(WTW)were measured for each participant by both IOL Master 700 and IOL Master 500.

RESULTS: The IOL Master 700 measured S_w of AL, K_m, K₁, K₂, ACD, LT, CCT, WTW in cataract patients were 0.027mm, 0.112D, 0.148D, 0.162D, 0.015mm, 0.010mm, 2.355μm and 0.134mm, CoV was 0.115%-1.162%, ICC≥0.923, the maximum ICC of AL is 1.000, and all measurements had high repeatability. The AL measured by IOL Master 700 and IOL Master 500 were(23.805±2.162)mm and(23.782±2.162)mm respectively, the difference was statistically significant(t=33.645, P<0.001). However, the 95% LoA was 0.003mm-0.043mm, and the AL measured by the two biometers was significantly correlated(r=1.000, P<0.001)with good agreement. The AL detection rates were 93.8%(211/225)for IOL Master 700 and 87.6%(197/225)for IOL Master 500, the difference was statistically significant(χ²=5.147, P=0.023).

CONCLUSION: IOL Master 700 demonstrates excellent repeatability in ocular biometric measurements including AL, K_m, K₁, K₂, ACD, LT, CCT and WTW for cataract patients, especially in AL measurement. IOL Master 700 is in good agreement with IOL Master 500 in measuring AL, however the IOL Master 700 has a higher detection rate for AL in patients with severe opacity and subcapsular opacity in their lens.