title: Determination of Personalized IOL-Constants for the Haigis Formula under Consideration of Measurement Precision.
abstract: The capabilities of a weighted least squares approach for the optimization of the intraocular lens (IOL) constants for the Haigis formula are studied in comparison to an ordinary least squares approach. The weights are set to the inverse variances of the effective optical anterior chamber depth. The effect of random measurement noise is simulated 100000 times using data from N = 69 cataract patients and the measurement uncertainty of two different biometers. A second, independent data set (N = 33) is used to show the differences that can be expected between both methods. The weighted least squares formalism reduces the effect of measurement error on the final constants. In more than 64% it will result in a better approximation, if the measurement errors are estimated correctly. The IOL constants can be calculated with higher precision using the weighted least squares method.
authors.affiliation: Institute of Experimental Ophthalmology, Saarland University, Homburg, Germany.
authors.forename: Simon
authors.identifier: http://orcid.org/0000-0002-6406-7795
authors.initials: S
authors.lastname: Schröder
authors.affiliation: University Eye Clinic, Vienna, Austria.
authors.forename: Christina
authors.initials: C
authors.lastname: Leydolt
authors.affiliation: University Eye Clinic, Vienna, Austria.
authors.forename: Rupert
authors.initials: R
authors.lastname: Menapace
authors.affiliation: Institute of Experimental Ophthalmology, Saarland University, Homburg, Germany.
authors.forename: Timo
authors.initials: T
authors.lastname: Eppig
authors.affiliation: Institute of Experimental Ophthalmology, Saarland University, Homburg, Germany.
authors.forename: Achim
authors.initials: A
authors.lastname: Langenbucher
mesh_terms: D006801:Humans; D007908:Lens, Crystalline; D008962:Models, Theoretical; D009907:Optometry / Q000379:methods*