Posters

Accuracy of intraocular lens power calculation formulae using the IOLMaster in eyes with varying grades of axial myopia (length greater than 24 mm) in an Indian setting

Poster Details

First Author: A.Braganza INDIA

Co Author(s):    V. Kharbanda   M. Kurian   R. Shetty   A. Heda           

Abstract Details

Purpose:

To assess the predictability of Intraocular Lens power calculations using IOL Master and four different IOL power calculation formulae (SRK/T, Holladay 1, Hoffer Q and Haigis) in eyes with axial length of > 24 mm.

Setting:

Super Speciality Eye Hospital in Bangalore India

Methods:

This retrospective study comparative study of 115 eyes with axial length > 24 mm of patients undergoing routine phacoemulsification. Preoperative Axial Length and keratometric power were measured by the IOLMaster, and power of the implanted IOL was determined using SRK/T, Holladay 1, Hoffer Q and Haigis formulas. Eyes were divided into mild (24-26 mm), moderate (26-28 mm), high (28-30 mm) and very high (> 30 mm) myopia. Predicted refractive outcomes were compared to actual refractive outcomes postoperatively. Mean absolute error (MAE) was the absolute value of the difference between actual and predicted spherical equivalences of postoperative refractive error

Results:

Mean Absolute Error for eyes with axial length between 24-28 mm using SRK/T, Holladay 1, Hoffer Q and Haigis formulae were 0.34, 0.47, 0.47 and 0.45 respectively, whereas for eyes with axial length > 28 mm, MAE using SRK/T, Holladay 1, Hoffer Q and Haigis formulae were 0.79, 1.17, 1.17 and 0.56 respectively. The proportion with an absolute error (AE) of less than 1 D was greatest in the SRK-T formula (89.56%), followed by those in the Holladay 1 (81.74%), Hoffer Q (78.26%), Haigis formula (90.43).

Conclusions:

The IOL power calculation using Haigis formula showed best results for post-operative refractive status in eyes with axial length > 28 mm, whereas SRK-T formula gave best results for eyes with axial length between 24-28 mm.

Financial Disclosure:

NONE