Effect of astigmatism on emmetropization and treatment of amblyopia in young children

Objective To investigate the effect of different astigmatisms on emmetropization and amblyopia. Methods Retrospective case series study. Two hundred and fifty-eight eyes of 138 children were divided into 3 groups: a normal control group (107 eyes) and an astigmatism group 1 (85 eyes) and group 2 (66 eyes) according to their degree of astigmatism.Refractive status and visual acuity (VA) were measured and compared at the beginning and at 1,2, 3, 4 and 5 years. Astigmatism was measured and compared at the beginning and end. Results Refractive status: the normal control group and the astigmatism group 1 had a significant decrease in refractive status at 1, 2 and 3 years (P＜0.05 for both). Astigmatism group 2 had a significant decrease in refractive status every year (F=24.65, P＜0.05). No significant differences were found in refractive status when the normal control and the astigmatism group 1 were compared at corresponding times. Significant differences were found in years 4 and 5 between the astigmatism group 2 and the other two groups. Visual acuity: the normal control and astigmatism group 1 had a significant improvement in visual acuity in years 1 and 2; there was a significant improvement in year 1 in the astigmatism group 2. The intergroup results for corresponding times were not statistically significant for the normal control and astigmatism group 1. There was a statistically significant difference between astigmatism groups 2 and 1, and between group 2 and the normal group in years 2, 3, 4 and 5.The amount of astigmatism decreased significantly in the astigmatism group 2 between the first and last check-ups (t=3.1440, P=0.021). Conclusion Astigmatism≥ 1.0 D is found to accelerate emmetropization. But amblyopia could not be completely cured. Astigmatism＜1.0 D has no influence on emmetropization and amblyopia. Key words: Astigmatism;  Emmetropization;  Amblyopia;  Child