The relationship between patient age and astigmatism magnitude after congenital cataract surgery

PURPOSE. To evaluate the magnitude of refractive astigmatism after congenital cataract surgery and to define its correlation with patient age. METHODS. The authors retrospectively reviewed the charts of all pediatric patients who underwent congenital cataract extraction with intraocular lens (IOL) implantation through a 3.0-mm clear corneal incision from 1998 to 2003, and had no suture removal for 5 months afterward. Thirty-four children were included, aged 2 months to 15 years. Refractive astigmatism was assessed manually 1 week, 3 months, and 5 months after surgery by an experienced optometrist. The paired t test was used to compare the magnitude of postoperative astigmatism at different postoperative periods. Spearman correlation was used to determine the correlation between patient age and the postoperative refractive astigmatism. RESULTS. Mean refractive astigmatism in all patients was 1.8±1.5 diopters (D) at 1 week postoperatively. It significantly decreased to 1.0±0.7 D at 3 months postoperatively (p=0.001), and to 0.8±0.7 D at 5 months postoperatively (p=0.03). The change in astigmatism was significantly greater during the first 3 postoperative months than during the following 2 months (p=0.04). Patient age was significantly correlated with 1 week postoperative astigmatism (Spearman coefficient, r = -0.46; p=0.006) and with 3 months postoperative astigmatism (Spearman coefficient, r =-0.37; p=0.03). CONCLUSIONS. Congenital cataract surgery using a small, clear corneal incision for IOL implantation caused high early postoperative astigmatism, which spontaneously regressed thereafter. Younger patients had higher early postoperative astigmatism.