AIM: To assess the consistency of the new anterior segment analyzer, MS-39, the Sirius and Pentacam in measuring corneal white-to-white(WTW)and central anterior chamber depth(ACD), and to compare their differences in guiding implantable collamer lens(ICL)size selection.

METHODS: Retrospective case study. A total of 210 consecutive patients(420 eyes)who treated at the Ophthalmology Refractive Surgery Center of the First Affiliated Hospital of Xi'an Jiaotong University between September 2019 and September 2020 were enrolled. Three anterior segment analysis systems, MS-39, Sirius, and Pentacam, were utilized to assess the WTW and ACD, with comparative analysis of the results. The sizing of the ICL V4c was simulated using the method recommended by the STAAR company. Data correlation and consistency were evaluated.

RESULTS: The WTW measurement results obtained from MS-39, Sirius, and Pentacam were 11.39±0.35, 11.42±0.36, and 11.46±0.35 mm, respectively. Notably, the WTW measurement value from MS-39 was significantly lower than that from Pentacam(P=0.002), while no statistically significant differences were observed between MS-39 and Sirius, or between Sirius and Pentacam(all P>0.05). The WTW measurements from the three devices exhibited a strong positive correlation, with correlation coefficients(r)of 0.942 between MS-39 and Sirius, 0.925 between MS-39 and Pentacam, and 0.882 between Sirius and Pentacam(all P<0.0001). The ACD measurements values from the MS-39, Sirius and Pentacam were 3.28±0.22, 3.28±0.24, and 3.21±0.23 mm, respectively. While, no statistically significant difference was found between MS-39 and Sirius(P>0.05), both measurements were significantly higher than that of Pentacam(both P<0.0001). The ACD measurements also demonstrated a strong positive correlation, with r values of 0.959 between MS-39 and Sirius, 0.947 between MS-39 and Pentacam, and 0.932 between Sirius and Pentacam(all P<0.0001). In terms of ICL size selection based on the measurements from the three devices, the 12.6 mm size was the most frequently selected, while the 13.7 mm size was the least common, the distribution of size selections across the devices was similar.

CONCLUSION: MS-39 demonstrated strong positive correlation with both Sirius and Pentacam for WTW and ACD measurements, indicating that the results can be considered clinically interchangeable. Furthermore, the outcomes derived from MS-39 for ICL size selection were closely aligned with those from Sirius and Pentacam, suggesting its clinical feasibility.