Comparison of SRK-T, Barrett, Hill-RBF, and Lada’s super-formula in predicting refractive outcomes after cataract surgery in extreme myopic eyes

Session Details

Session Title: IOL Power Calculations, Post-LASIK & Extreme Eyes

Session Date/Time: Tuesday 25/09/2018 | 14:00-16:00

Paper Time: 15:16

Venue: Room A2

First Author: : P.Kusumgar INDIA

Co Author(s): :    M. Kurian   S. Bhatnagar   N. Israni              

Abstract Details

Purpose:

To compare the accuracy of SRK-T, Barrett, Hill-RBF and Lada’s super-formula in predicting refractive outcomes after cataract surgery in extreme myopic eyes.

Setting:

Narayana Nethralaya, Bangalore, India

Methods:

A retrospective case series of 30 eyes with axial length greater than 30mm and Sensar (AR40) IOL implantation following uncomplicated phacoemulsification. The prediction error at 4 weeks postoperatively (PE) was computed to determine the formula with minimum error.

Results:

The mean axial length was 31.42 ± 1.62 mm. The mean emmetropic IOL powers predicted by the formulae namely SRK T, Barrett, Hill RBF and Lada’s Super-formula were -2.55 ± 3.21 D, -0.75 ± 2.5 D, -3.35 ± 4.43 D, -1.15 ± 2.64 D respectively. The mean IOL power used was -1.15 ± 2.81 D. Expected post op refraction with the four formulae were -0.2 ± 0.1 (SRK-T), -0.19 ± 0.2 (Barrett), - 0.21 ± 0.18 (Hill-RBF), -0.17 ± 0.09 (Lada’s). Post op mean refractive spherical equivalent at 1 month was -0.54 ± 1.21 D.

Conclusions:

In our group of extreme myopic eyes the differences between the formulae were statistically and clinically insignificant though the Hill-RBF gave the minimum prediction error.

Financial Disclosure:

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