Posters

Comparison of 4 modern intraocular lens calculation formulas for a monofocal aspheric toric and monofocal aspheric intraocular lens

Poster Details

First Author: E.Rodriguez ARGENTINA

Co Author(s): H. Scarfone   S. Fanego                 

Abstract Details

Purpose:

To evaluate the accuracy of 4 formulas (Haigis, Barret Universal II, Radial base basis function RBF, Olsen) that allows to calculate the AcrySoft IQ SN60WF and AcrySoft IQ Toric SN6ATx.

Setting:

CLÍNICA DE OJOS TANDIL. Buenos Aires

Methods:

Retrospective case series. Patients who were treated with cataract surgery with monofocal or monofocal toric insertion for 12 months. Preoperative biometric measurements were obtained from the Lenstar LS 900. Optimized IOL constants were calculated to reduce the average refraction prediction error. Only one eye per patient was included in the analysis, resulting in a total of 205 cases. The study populations were separated into 3 subgroups by the axial length.The performance of each formula was compared with the predicted spherical equivalent error. We excluded patients who presented pathologies or previous eye surgeries.

Results:

For the SN60WF, the mean of the prediction error, in order from lowest to highest, was Haigis (-0.04), Hill - RBF (-0.06), Olsen (-0.120) Universal II de Barret (-0.205) and results for The SA60ATx were Haigis (0.002), Hill-RBF (-0.109), Olsen (-0.185) and finally Universal II de Barret (-0.220). The Friedman test states that there were differences between the prediction errors for the various formulas (P <0.01). The analysis of the comparisons by the Wilcoxon pairs for non-parametric samples has been a statistically significant difference between Haigis and the other formulas for both types of IOL (P <0.01).

Conclusions:

The Haiguis formula had the best outcomes in terms of accuracy of postoperative spherical equivalent as measured by difference in mean ranks of Wilcoxon signedrank comparisons for both of the IOL models in this study.

Financial Disclosure:

None