Posters

Post-LASIK biometry using Borasio myopic/hyperopic IOLMaster regression formula (BMR/BHR): a step beyond BESSt?

Poster Details

First Author: E.Borasio UNITED ARAB EMIRATES

Co Author(s):                  

Abstract Details

Purpose:

To evaluate the accuracy of two new post LASIK/PRK regression formulas called BMR (myopic formula) and BHR (hypermetropic formula) and comparing them to other formulas such as BESSt, Shammas PL Myopia and Haigis L.

Setting:

Moorfields Eye Hospital Dubai

Methods:

We retrospectively compared the mean errors (ME) and median absolute errors (MAE) of each formula in a group of 136 consecutive eyes undergoing phacoemulsification following LASIK/PRK. Eyes were grouped according to their pre-refractive surgery refractive error (102 myopia; 34 hypermetropia).

Results:

In the Myopic group the ME was: BMR (0.07± 0.99 D), BESSt 2 Myopia (0.54± 1.23 D), BESSt 1 (-0.05± 1.30 D), Shammas PL Myopia, (-1.05± 1.12 D), Haigis L (-0.89± 1.23 D). The MAE was: BMR (0.69± 0.73 D), BESSt 2 Myopia (0.98± 0.91 D), BESSt 1 (1.07± 0.73 D), Shammas PL Myopia, (1.32± 0.79 D), Haigis L (1.23± 0.89 D). In the Hypermetropic group the ME was: BHR (0.28± 0.81 D), BESSt 2 Hyperopia (0.16± 1.08 D), BESSt 1 (-0.72± 0.99 D), Shammas PL Hyperopia (-0.09± 1.14 D). The MAE was: BHR (0.70± 0.48 D), BESSt 2 Hyperopia (0.83± 0.69 D), BESSt 1 (1.06± 0.60 D), Shammas PL Hyperopia, (0.83± 0.76 D).

Conclusions:

In the Myopic group, BMR was statistically significantly more accurate than BESSt 1 (p<0.001) and BESSt 2 Myopia (p:0.033), Shammas PL-Myopia (p<0.001) and Haigis L (p<0.001) and had the lowest SD in the group (0.99 D). 30% more eyes were <0.50 D from the target compared to BESSt 1 and 2. In the Hypermetropic group, BHR was statistically significantly more accurate than BESSt 1 (p<0.001) and Shammas PL-Hyperopia (p:0.03) and was as accurate as BESSt 2 (p>0.05). BHR has the lowest SD in the group (0.81 D). 13% more eyes were <0.50 D from the target compared to BESSt 2, and 50% more compared to BESSt 1. FINANCIAL INTEREST: One of more of the authors... has significant investment interest in a company producing, developing or supplying product or procedure presented