Abstract
Purpose :
To compare and assess the agreement of the axial lengths (AL) measured by MYAH (MY), Myopia Master (MM), and IOL Master (IOLM) in myopic children and evaluate the strength of the relationships of AL with the spherical component (SC) and spherical equivalent (SE) of the
refractive error for each device.
Methods :
120 eyes of 60 myopic children were included. The median [IQR] age was 10 [3.5 years]; 43.3% were female. AL measurements were performed on each eye using MY (Topcon), MM (Oculus), and IOLM. Refractive error was measured with the Nidek auto-refractor. Linear mixed regression examined the association between the type of machine and AL, using individual and eye random-intercepts, and the type of device as fixed-effect. Thereafter, the Wald test and intra-class correlation coefficient assessed if there are any mean AL differences and agreement among the three devices, respectively. The association between SC and SE with AL for each machine was evaluated with linear mixed regression, using individual random-intercept, and SC and SE as fixed-effects. Correspondingly, the strength of the relationships between AL and each of the SC and SE from the 3 devices were determined using overall R-squared values.
Results :
There was no statistical difference between the mean AL of MM and MY (β = 0.002, 95% CI = -0.040 to 0.044) and that of IOLM and MY (β = 0.037, 95% CI = -0.005 to 0.079). According to the Wald test, there were no significant mean AL differences among the 3 devices.
Additionally, there was strong agreement among the three devices as observed from the high correlation (ICC = 0.982, 95% CI = 0.973 to 0.988) between the AL values in the same eye and the same person. Significant negative relationships were observed for SC (β = -0.417, 95% CI = -0.502 to -0.332 [MY]; β = -0.421, 95% CI = -0.507 to -0.336 [MM]; β = -0.445, 95% CI = -0.531 to -0.359 [IOLM]) and SE (β = -0.404, 95% CI = -0.487 to -0.321 [MY]; β = -0.408, 95% CI = -0.492 to -0.324 [MM]; β = -0.429, 95% CI = -0.514 to -0.343 [IOLM]) with AL in all three devices. Overall R-squared values for the relationships of SC and AL were 0.617, 0.617, and 0.622, and for those of SE and AL were 0.610, 0.609, and 0.610 for MY, MM, and IOLM respectively.
Conclusions :
The three devices exhibited excellent agreement in the AL measurements. The considerable proportion of variance that can be explained by SC and SE should be noted.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.