Objective  To  investigate the performance and progression of refractive errors and to evaluate the ocular development in the children with ametropia. 
Methods  The study was carried out from August 1,2011 to January 31,2012 at Department of Strabismus and pediatric ophthalmology, Ophthalmological Center of Tianjin Medical University. 75 children (40 boys, 80 eyes; 35 girls, 70 eyes), aged 2 to 18 years old, were randomly selected from outpatients. The patients were divided into three groups by age, Group A: 2 to <6 years, Group B: 6 to <11 years old and Group C: 11 to <18 years. Static diopter was measured with cyclopegic retinoscopy or subjective refraction after compound tropicamide eye drops applied for 3 times successively and then was calculated to equivalent spherical degree(SE). Ocular biometric parameters were recorded from IOL Master, including axis length(AL), central corneal thickness(CCT), anterior chamber depth(ACD), lens thickness(LT), Maximum corneal refractive power and Warp direction, Minimum corneal refractive power and Warp direction, and corneal horizontal diameter (white-to-white, WTW distance). The data were analyzed with SPSS19.0 software, and P<0.05 was considered statistically significant. 
Result  The univariate general linear model showed that age grouping was a correlated factor for changes of major eye biometric parameters (P<0.05), while gender had no correlation with them. (P>0.05). Differences of SE,LT,AL and ACD of the both eyes among age groups had statistical significance (F=7.121, 3.765, 15.104, 11.781; 5.049, 5.341, 12.387, 11.914; P<0.05). when children grow older, equivalent spherical, axis length and anterior chamber depth all increased, accompanied by the decrease of lens thickness. There was no significant difference among these three age groups in central corneal thickness, corneal astigmatism, corneal astigmatism axial and corneal horizontal diameter. Comparison of the right eye and left eye development: in Group A and Group B, there was no significant difference between all eye biometric parameters (P>0.05); in Group C, the data of static diopter, axis length and anterior chamber depth were higher than the left eye(P=0.001,0.003,0.046).
Conclusion  The changes of major biometric parameters of the ametropic eye may be influenced by aging. There is an active myopization exists between the ages of 5-10 in both eyes. After the age of 10, the left eye development remains stable, but the progress of myopization in right eyes continues.