METHODS: Totally 40 IXT children were divided into three groups according to the different types of the IXT patients, the convergence insufficiency group(12 children), the basic group(18 children)and the divergence excess group(10 children). And the 20 non-exotropia children were set up as the control group. AMP was measured with improved push-up test, and AF was measured with turning over convex and concave lens test. NPC was measured with push-up test. AC/A ratio were measured with the lens gradient method. PRC was measured with BO prism. The binocular accommodative and convergence function of four groups were compared.

RESULTS: The difference of AMP, AF, NPC, AC/A ratio and PRC among four groups was significant difference(P<0.05), and we did the further pair wise comparisons. AMP of the IXT group was less than the control group, and AMP of the convergence insufficiency group was the least; AF of the convergence insufficiency group was less than the basic group and the control group; NPC of the convergence insufficiency group was the largest; AC/A ratio of the convergence insufficiency group and the basic group was lower than the other two groups; PRC of the IXT group was less than the control group when fixating at near target of 33cm, and the mean of the convergence insufficiency group was the least; PRC of the IXT group was less than the control group when fixating at far target of 6mo(P<0.05).

CONCLUSION: There are differences in the ocular function of accommodation and convergence in different types of IXT children, and the function of the convergence insufficiency IXT is the worst. The binocular accommodative and convergence function of IXT children is worse than non-exotropia children.