Predictive value of various IOL power calculation formulae used in paediatric cataract surgery

Session Details

Session Title: Paediatric Cataract Surgery

Session Date/Time: Tuesday 13/09/2016 | 08:00-10:30

Paper Time: 09:32

Venue: Hall C1

First Author: : R.Deshpande INDIA

Co Author(s): :    K. Dole   M. Deshpande                 

Abstract Details

Purpose:

To evaluate the predictive value and accuracy of various formulae used for IOL power calculation in pediatric patients undergoing cataract surgery.

Setting:

A tertiary eye care centre in western India.

Methods:

This Prospective, non-randomized, observational study was conducted at a tertiary eye care centre. All patients from age 1 to 18 years undergoing cataract surgery with in the bag implantation of IOL were included. Biometry was done and IOL power was calculated using SRK-T, SRKII, Hoffer-Q, and Holladay-I formulae. IOL implantation was done according to the SRK-T after undercorrection using guidelines of Enyedi et al. Post operatively spherical equivalent was calculated at 5 weeks and mean absolute prediction error (APE) of each formula was calculated.

Results:

63 eyes of 41 patients. 76% males, 53.70% had bilateral cataract and 36.5% less than 5 years old. Mean age at surgery was 7.17 ±4.27 years. Mean APE lowest with SRKT formula was 1.04 D, HofferQ 1.91 D, 1.06 D with SRKII and 1.91 D with HolladayI. Deviation of greater than ±1 D from the expected refraction seen in 29.78% patients with SRKT, 61.70 % patients with HofferQ, 31.91% with SRKII and 42.55% with HolladayI. Age, Keratometry, ACD and corneal astigmatism affected the accuracy of formulas whereas axial length and lens thickness had no influence on accuracy of any formula.

Conclusions:

There was no significant difference in the predictive accuracy between SRK-T, SRK II and Holladay-I but Hoffer-Q yielded significantly high error. The variables included in the study showed inconsistent effect on accuracy of various formulae. The SRK-T formula had the least overall Mean APE and thus we recommend SRK-T formula for IOL power calculation in pediatric cataract patients. However, further studies are needed to determine the most accurate formula in pediatric patients.

Financial Disclosure:

NONE