Vector analysis of high early postoperative astigmatism after congenital cataract surgery

Corneal astigmatism is a well-documented finding after cataract surgery. Postoperative astigmatism is of greater importance in children than in adults, because of its adverse effect on vision development and the risk of amblyopia. The purpose of this study was to evaluate refractive outcomes in eyes- which had high early postoperative astigmatism after congenital cataract surgery.

We retrospectively reviewed the charts of 74 children (112 eyes), who underwent congenital cataract extraction with intraocular lens implantation, using limbal incision, scleral tunnel, or clear corneal incision. Thirty-two eyes of 28 children, aged 2 months to 11 years, had astigmatism of 3.0 diopters (D) or more when assessed 1 week after surgery. Changes in cylinder vector, spherical equivalent (SEQ) and defocus equivalent (DEQ) between 1 week and 5 months postoperatively were calculated for each group.

Mean SEQ and DEQ were 0.7+/-3.5 D and 5.1+/-2.8 D, respectively, at 1 week postoperatively- and -0.2+/-3.4 D and 3.1+/-2.3 D, respectively, at 5 months postoperatively in the three groups. DEQ levels showed a significant reduction during the 5-month follow-up period (P<0.001). The mean astigmatism vector was 2.9+/-3.3 D x 93 degrees in all the three groups 1 week postoperatively- and 0.2+/-1.1 D x 153 degrees at 5 months after surgery. A significant change during 5-month follow-up in cylinder vector (P<0.02) and SEQ (P=0.01) was found after operations using scleral tunnel technique.

Children- who underwent congenital cataract surgery by different surgical techniques showed a significant spontaneous reduction in DEQ values. A significant change in cylinder vector and SEQ was found after operations using scleral tunnel technique.