Clinical validation of an algorithm to correct the error in the keratometric estimation of corneal power in normal eyes

Mateo

et al. 2013

Cornea

Self Cite

mentioning

confidence: 99%

Algorithm for Correcting the Keratometric Error in the Estimation of the Corneal Power in Eyes With Previous Myopic Laser Refractive Surgery

Camps

Mateo

et al. 2013

Cornea

Self Cite

“…Although there were statistically significant differences among systems in K1, K2 and corneal astigmatism (p < 0.01), these differences were within a clinically acceptable level. Mean differences in keratometry between devices were close to 0.25 D or below, and errors of 0.50 D in corneal power estimation can lead to as much as 0.50 D of error in IOL power calculation, which is the minimum IOL power step provided by most manufacturers.…”

Section: Discussionmentioning

confidence: 89%

Validation of keratometric measurements obtained with an intraoperative image‐guided system: intra‐session repeatability and interchangeability with an optical biometer

Ruiz-Belda

Rodrigo

Clinical and Experimental Optometry

2018

“…[ 14 15 19 ] However, we still obtained statistically significant and clinically relevant differences between the adjusted calculation, and the real power of the IOL implanted that was selected according to the SRK-T formula outcomes. As the accuracy of the IOL-Master for obtaining AL measurements has been widely demonstrated,[ 20 ] the ELP was thought to be a critical factor for the presence of a relatively limited predictability with the accommodating IOL evaluated. For such purpose, an expression for estimating an optimized ELP according to some preoperative parameters, designated as adjusted ELP, was obtained by means of multiple linear regression.…”

Section: Discussionmentioning

confidence: 99%

Positional accommodative intraocular lens power error induced by the estimation of the corneal power and the effective lens position

Camps

Ramón³

et al. 2015

Indian J Ophthalmol

Self Cite

Purpose:To evaluate the predictability of the refractive correction achieved with a positional accommodating intraocular lenses (IOL) and to develop a potential optimization of it by minimizing the error associated with the keratometric estimation of the corneal power and by developing a predictive formula for the effective lens position (ELP).Materials and Methods:Clinical data from 25 eyes of 14 patients (age range, 52–77 years) and undergoing cataract surgery with implantation of the accommodating IOL Crystalens HD (Bausch and Lomb) were retrospectively reviewed. In all cases, the calculation of an adjusted IOL power (PIOLadj) based on Gaussian optics considering the residual refractive error was done using a variable keratometric index value (nkadj) for corneal power estimation with and without using an estimation algorithm for ELP obtained by multiple regression analysis (ELPadj). PIOLadj was compared to the real IOL power implanted (PIOLReal, calculated with the SRK-T formula) and also to the values estimated by the Haigis, HofferQ, and Holladay I formulas.Results:No statistically significant differences were found between PIOLReal and PIOLadj when ELPadj was used (P = 0.10), with a range of agreement between calculations of 1.23 D. In contrast, PIOLReal was significantly higher when compared to PIOLadj without using ELPadj and also compared to the values estimated by the other formulas.Conclusions:Predictable refractive outcomes can be obtained with the accommodating IOL Crystalens HD using a variable keratometric index for corneal power estimation and by estimating ELP with an algorithm dependent on anatomical factors and age.