DIFFERENCE BETWEEN TARGET AND POST OPERATIVE REFRACTIVE ERROR FOLLOWING CONGENITAL CATARACT SURGERY IN PAEDIATRIC PATIENTS VISITING ARMED FORCES INSTITUTE OF OPHTHALMOLOGY

Abstract

Objective: To determine the difference between target and postoperative refraction in children with congenital cataract.

Study design:    Prospective interventional study

Place and Duration of Study: This study was conducted at Armed Forces Institute of Ophthalmology from May 2017 to May 2018.

Methods: This study was conducted on 38 eyes suffering from congenital cataract. Age at the time of surgery, axial length, average keratometry reading, estimated refraction, and the power of IOL implanted were recorded. Spherical equivalent of post-op refraction at 3 months after surgery was noted. The difference between the estimated and actual postoperative refraction was termed as prediction error. Age, keratometry, and axial length were then assessed for its effects on prediction error.

Results:  Overall the mean prediction error was 1.43±1.98 D. The mean prediction errors in eyes with axial lengths ⩾20 mm were 0.96± 1.03 D and in eyes <20 mm were 5.50± 3.49 D. The mean prediction errors in eyes in children aged ⩾4 years were 0.14± 0.61 D) and in children aged < 4 years was 2.60± 2.07 D. The differences between the prediction errors for both axial length and age were statistically significant (p<0.05).

Conclusion:       IOL power calculations in eyes with axial length less than 20 mm and children less than 4 years of age are prone to postoperative refractive errors. This study has reflected that adult based formulas are not reliable in pediatric age group.