Efficiency comparison of the Dem with axial length to corneal radius ratio in predicting refractive state of 3-14 years old children

AIM: To assess the association between the Dem, axial length/corneal radius ratio(AL/CR ratio), and the refractive status of children aged 3 to 14, compare the efficiency of Dem with AL/CR ratio in predicting myopia, and to explore a more effective method for quantitatively predicting the refractive state of children.METHODS: This cross-sectional study involved 519 children aged 3 to 14, including 519 eyes(data from the right eyes were used). All participants were out-patients at the ophthalmic clinic of Xi'an No.1 Hospital from March 2021 to December 2022. The axial length(AL), keratometry(K), Dem, and spherical equivalent refraction(SER)were recorded before ciliary paralysis, and myopia was defined when the SER ≤-0.50 D.RESULTS: There was a positive correlation between SER and Dem(r=0.88, P<0.01), and a negative correlation between SER and the AL/CR ratio(r=-0.87, P<0.01)in children aged 3-14. The optimal cutoff points for the Dem and AL/CR ratio were 20.40 D, and 3.02, respectively. Myopia could be diagnosed when the Dem ≤20.40 D or the AL/CR ratio ≥3.02. SER decreased by 0.57 D for every 1 D decrease in Dem and by 1.00 D for every 0.06 increase in the AL/CR ratio. The area under the ROC curve(AUC)for Dem(0.958)was significantly greater than that for the AL/CR ratio(0.940).CONCLUSION: There is a positive correlation between SER and Dem, and a negative correlation between SER and the AL/CR ratio in children aged 3-14. Dem is more efficient than the AL/CR ratio in myopia assessment. The eye biometrics directly provide Dem values, which is more convenient for calculating the dose-effect relationship with SER, thus making it more efficient for predicting SER in children.