Long-term visual acuity and its predictors after surgery for congenital cataract: findings of the British congenital cataract study.

PURPOSE

To report long-term postoperative visual acuity in a nationally representative group of children with congenital/infantile cataract and to investigate the factors associated with poor vision.

METHODS

All children aged less than 16 years in the United Kingdom who had newly diagnosed congenital/infantile cataract in a 12-month period during 1995-1996 (the British Congenital/infantile Cataract Study) were traced through their managing ophthalmologists. Outcome data were collected at least 6 years after diagnosis, by using specifically designed questionnaires. Ordinal regression analysis identified factors associated with postoperative acuity.

RESULTS

Of 153 children who had surgery, complete data were available in 122 (85%). Median age at follow-up was 7 and 6.91 years, respectively, for bilateral and unilateral disease. Median age at surgery was 4.57 months in bilateral and 2.99 months in unilateral cases, with 40% and 45%, respectively, of children operated on by 3 months. Median (range) postoperative acuity was 6/18 (6/5, no perception of light) in bilateral and 6/60 (6/5, no perception of light) in unilateral disease. Poor compliance with occlusion was the factor most strongly associated with poorer acuity in both unilateral and bilateral disease: the odds of worse vision in unilateral cataract were 7.92 times greater with <50% versus 100% compliance (95% CI 1.68-37.26). In bilateral disease, odds of worse vision were reduced with each month of decreasing age at surgery (0.98, 95% CI 0.94-0.99), but increased by the presence of additional medical conditions (3.53, 95% CI 1.08-11.44) and the presence of postoperative ocular complications (2.94, 95% CI 1.38-6.51).

CONCLUSIONS

These findings support a secular improvement in postoperative acuity in bilateral, and to a lesser extent, unilateral disease. Nevertheless early detection of congenital cataract through effective newborn screening and improving concordance with occlusion both remain priorities. Further improvements in outcomes in unilateral disease are necessary before parents can be advised universally that treatment will achieve a functionally useful "spare" eye.