Posters
Accuracy of different IOL power calculation formulas in eyes with long axial length
Poster Details
First Author: A.Abreu PORTUGAL
Co Author(s): J. Coelho V. Lages M. Lume R. Salgado M. Brochado P. Meneres
Abstract Details
Purpose:
To compare the accuracy of intraocular lens (IOL) power calculation formulas in eyes with axial length (AL) superior to 26 mm.
Setting:
Department of Ophthalmology of a tertiary referral centre in Oporto, Portugal - Centro Hospitalar Universit�Ã�¡rio do Porto
Methods:
Retrospective chart review of patients who underwent cataract surgery with IOL implantation at our center from January to December 2016. Inclusion criteria were an AL superior to 26 mm, availability of preoperative AL, preoperative ACD data, 1-month postoperative refraction data, and uncomplicated surgery. AL, corneal power and anterior chamber depth (ACD) were measured with IOL Master. Third generation formulas (Hoffer Q, SRK/T, Holladay and Haigis) and a fourth generation formula (Barrett Universal II) were used to predict IOL powers. The predictive accuracy of the formulas was analyzed by comparison of the mean error (ME) and the mean absolute error (MAE).
Results:
Seventy-four eyes (48 patients) were included. Mean AL was 28.01�Â�±2.01 mm. Mean ACD was 3.45�Â�±0.34 mm. Mean postoperative spherical equivalent was -0.76�Â�±0.76 diopters. The ME and MAE from the Barrett formula were the smallest and the ME and MAE from the Hoffer Q formula were the largest. All formulas, except SRK/T, presented statistically significant differences in MAE between the group of eyes with AL between 26 and 29 mm and the group with AL>29 mm, all presenting better results in the group with smaller AL. In eyes with AL>29 mm, SRK/T presented the smallest MAE.
Conclusions:
IOL power prediction may be inaccurate in high myopic patients. In our study, the Barrett Universal II formula produced more in-accurate results in high myopic eyes, although in eyes with AL superior to 29 mm SRK/T formula had the smallest MAE.
Financial Disclosure:
NONE
