Posters

Intraocular lens power calculation accuracy in axial myopia using intraoperative aberrometry and novel formulas

Poster Details

First Author: J.Chaves PORTUGAL

Co Author(s):    M. Raimundo   J. Simão   A. Rosa   M. Quadrado   J. Neto-Murta        

Abstract Details

Purpose:

In this study we compare the accuracy of intraoperative aberrometry (IA) versus modern IOL power calculation formulas in eyes with axial myopia not previously submitted to refractive surgery.

Setting:

Centro Hospitalar e Universitário de Coimbra (CHUC), Coimbra, Portugal

Methods:

We included 51eyes with axial length≥25.0mm not previously submitted to refractive surgery that underwent cataract surgery with a trifocal IOL(PanOptix,Alcon) aided by IA(ORA,Alcon). The post-operative spherical equivalent for the same implanted IOL was estimated using IA, the Barrett UniversalII, Hill-RBF2.0, LADAS SuperFormulaAI, SRK-T, Haigis, Holladay1, HofferQ, as well as the one-center Wang-Koch optimized SRK/TWK, HaigisWK and Holladay1WK. Outcomes included the median absolute prediction error (MedianAE)and the proportion of eyes within 0.25D, 0.50D and 1.0D of this prediction.Visual inspection of formula performance over axial length was achieved by fitting fractional polynomial models to the absolute prediction errors of each formula

Results:

The WK optimized Holladay1WK was the best performing formula(MedianAE 0.199D, MeanAE 0.23D, SD 0.283D)predicting 57.1% of eyes within 0.25D, 98.0% within 0.5D and 100% of eyes within 0.75D.The also WK optimized SRK/TWK was the second-best performing formula(MedianAE 0.213D, MeanAE 0.239D,SD 0.283D)with similar predictions within 0.25D(61.2%),0.50D(95.9%) and 0.75D(100%).The IA system followed in third place(MedianAE 0.231D, MeanAE 0.222D, SD 0.271D)though with lower prediction percentage within 0.50D(89.8%) when compared to the WK optimized Holladay1WK and SRK/TWK. Despite these differences, paired comparisons between the top three formulas were not statistically different(Holladay1WK vs SRK/T WKp=0.379;Holladay1WK vs IA p=0.680)while outperforming all the other included formulas(allp<0.05)

Conclusions:

Our results support the use of the WK optimizations, namely the Holladay 1 WK, in axial myopia, with IA having equivalent performance in this axial length, significantly outperforming other commonly used formulas

Financial Disclosure:

None