Correlation between myopia and major biometric parameters of the eye: a retrospective clinical study

To investigate the relationship between myopia and changes in ocular biometry and macular thickness in young adults.

Two hundred sixteen eyes from 108 adults (23.3 +/- 6.3 years old, mean +/- SD) were measured for refractive status, corneal curvature, and axial components of the eye. Macular thickness was measured in 118 eyes (59 subjects) by optical coherence tomography. All eyes were categorized into emmetropia, low, moderate, or high myopia based on the refractive status. Biometric results from right eyes of all subjects were compared between sub-groups with the linear correlation analyzed between refraction and other parameters for each group.

The vitreous chamber depth was longest in high myopia, followed by the moderate myopia group, the low myopia group and finally the emmetropic group (p < or = 0.004). Average thickness of the inner and outer ring macula in all the myopia groups was significantly thinner than in the emmetropia group (p < or = 0.021). Among different macular regions, the inferior quadrant of the outer ring was consistently the thinnest in myopia. Corneal curvature, anterior chamber depth, and lens thickness measures were not associated with myopia.

Myopia in young adults is associated with an increase in vitreous length and a decrease in para-foveal thickness. The thinness in the retinal region inferior to the fovea appears to be more highly correlated with myopia than any other retinal region.