To investigate the changes of the axial length, corneal curvature and refractive power in infants with monocular congenital cataract.

A retrospective cohort study was carried out.The clinical data of 105 eyes of 105 cases with monocular congenital cataract who were received cataract extraction during January 2015 to December 2017 were collected in the First Affiliated Hospital of Zhengzhou University.According to the initial operation age, the infants were assigned to 3-6 month old group, 7-12 month old group and 13-18 month old group.The patients were followed-up for 12 months.Axial length, corneal curvature and refractive power were recorded in 3, 6 and 12 months after surgery.This study followed the Declaration of Helsinki, and written informed consent was obtained from each guardian prior to any medical examination.

The increasing value of axial length in 3-6 month old group was larger than that in 7-12 month old group, and increasing value in 7-12 month old group was larger than that in 13-18 month old group (all at P<0.001). The increasing value of axial length of operated eyes was larger than that of fellow eyes in both 3-6 month old group and 7-12 month old group during following-up, and so was in the 13-18 month old group at 6 months and 12 months after surgery (all at P<0.001). The ocular axial length of operated eyes was significantly shorter than that of the fellow eyes in three groups before operation (t=-10.420, P<0.001; t=-32.288, P<0.001; t=-2.370, P=0.024), and at 12 months after operation, the axial length of operated eyes was longer than that of the fellow eyes in the 13-18 month old group (t=18.513, P<0.001). No significant difference was found in the axial length between operated eyes and fellow eyes in both 3-6 month old group and 7-12 month old group (P=0.051, 0.062). The pre-operative corneal curvature was significantly larger than that of fellow eyes in both 3-6 month old group and 7-12 month old group (both at P<0.01), and was not significantly different in 13-18 month old group (P=0.433). There were not significant differences in corneal curvature in the three groups at 12 months after surgery (all at P>0.05). The change value of refractive power was gradually increased as aging at 12 months after surgery (all at P<0.001). The surgical eye amplitude of change in refractive diopter was higher than healthy eye, with significant difference between them (P<0.001).

The developing process of axial length and corneal curvature are interacted and coordinated in bilateral eyes in infants who received extraction surgery of monocular congenital cataract.It is better to remove the cataract as early as possible in infants.Refraction of bilateral eyes still has a trend to myopia, and the shifting amplitude of myopic power decreases with aging.

Cataract, congenital/surgery; Axial length; Corneal curvature; Refraction