Comparison of axial length, anterior chamber depth and intraocular lens power between IOLMaster and ultrasound in normal, long and short eyes

Purpose To compare the axial length (AL), anterior chamber depth (ACD) and intraocular lens power (IOLP) of IOLMaster and Ultrasound in normal, long and short eyes. Methods Seventy-four normal eyes (> 22 mm and < 25 mm), 74 long eyes (> 25 mm) and 78 short eyes (< 22 mm) underwent AL and ACD measurements with both devices in the order of IOLMaster followed by Ultrasound. The IOLP were calculated using a free online LADAS IOL formula calculator. Results The difference in AL and IOLP between IOLMaster and Ultrasound was statistically significant when all three groups were combined. The difference in ACD between IOLMaster and Ultrasound was statistically significant in the normal group (P<0.001) and short eye group (P<0.001) but not the long eye group (P = 0.465). For the IOLP difference between IOLMaster and Ultrasound in the normal group, the percentage of IOLP differences <10.5ID, >10.51 D<10.75ID, >10.75ID<11.01D, and >11.01D were 90.5%, 8.1%, 1.4% and 0%, respectively. For the long eye group, they were 90.5%, 5.4%, 4.1% and 0%, respectively. For the short eye group, they were 61.5%, 23.1%, 10.3%, and 5.1%, respectively. Conclusions IOLMaster and Ultrasound have statistically significant differences in AL measurements and IOLP (using LADAS formula) for normal, long eye and short eye. The two instruments agree regarding ACD measurements for the long eye group, but differ for the normal and short eye groups. Moreover, the high percentage of IOLP differences greater than 10.5ID in the short eye group is noteworthy.