COMPARISON OF OCULAR BIOMETRY AND CORNEAL CURVATURE AMONG MALAYSIAN EMMETROPES AND MYOPES

摘要

A cross sectional study was conducted by including 47 Malaysian subjects aged 18-35 years. The purpose is to find out the variations in ocular biometry according to refractive state and rule out the most contributing factor for the degree of myopia among Malaysia subjects. Keratometer and A-scan ultrasonography were used to measure the corneal curvature and biometric parameters respectively. Comparison of ocular components for gender and onset of myopia were done by using independent t-test. One wayANOVA was done to compare biometric parameters with refractive states. Comparison of the axial length (p=0.49), anterior chamber depth (p=0.28), lens thickness (p=0.06) and cornea radius (p=0.94) showed no significant difference based on age groups and gender. Lens thickness (p<0.05) showed significant difference based on onset of myopia. Refractive state has a significant relation to axial length (p<0.001), lens thickness (p=0.03), corneal radius (p<0.001) and AL/CR ratio (p<0.001). Axial length was having more effect on high myopia group whereas corneal radius and AL/CR ratio showed more effect on emmetropia group. There was a significant difference in biometric parameter, corneal curvature and AL/CR ratio between emmetropia and myopia except anterior chamber depth. In addition, there was a significant difference in lens thickness exits based on the onset of myopia. Axial length was the main morphological factor related to myopia. AL/CR ratio is a better index for categorizing the refractive statusof an individual than axial length alone.