Contrastive analysis of corneal horizontal diameter measurement by five instruments

Abstract

AIM: To analyze the correlation and consistency of five corneal diameter measurements.METHODS: Totally 25 cases(50 eyes)who underwent ICL implantation in West China Hospital. The preoperative horizontal corneal diameter was measured using measuring caliper, SIRIUS anterior eye assay system, IOL Master500, anterior segment OCT and UBM. RESULTS: The mean WTW distances were 11.54±0.30 mm as obtained with measuring caliper, 11.77±0.33mm with SIRIUS anterior eye assay system, 11.98±0.33mm with IOL Master500, 11.63±0.35mm with anterior segment OCT and 11.53±0.34mm with UBM. No statistical difference was found between measuring caliper and UBM, measuring caliper and anterior segment OCT, UBM and anterior segment OCT. The linear correlation analysis found significant correlation between the measurements of the five measurements. The Bland-Altman analysis for the measuring caliper and SIRIUS, measuring caliper and UBM, measuring caliper and anterior segment OCT found that the absolute values of 95% LOA upper and lower limits were less than 0.5mm.CONCLUSION: The results of the four kinds of corneal horizontal diameter measurements can be interchanged including SIRIUS, UBM, anterior segment OCT and measuring caliper. IOL Master500 results are the largest, that cannot be used as a diagnostic basis for measuring the size of corneal horizontal diameter. The results of other measurement equipment should be combined with clinical practice.

Keywords

• corneal diameter
• caliper
• SIRIUS anterior eye assay system
• IOL Master500
• anterior segment OCT
• UBM
• consistency analysis