Effect of cataract-induced refractive change on intraocular lens power formula predictions.

Cataract-induced refractive change () is the change in refraction induced by a cataract. It can amount to several diopters (D). It alters predicted errors in refraction following cataract surgery through changes in axial length measurement.

Standardizing sum-of-segments axial length using refractive index models.

Optical biometry uses interferometry to measure the axial length (AL) of the eye. Traditionally, one-variable regression formulas have converted the optical path length measured by a biometer to a geometric AL. An alternate calculation of axial length sums the individual segments of the eye (sum-of-segments AL).

Approximating sum-of-segments axial length from a traditional optical low-coherence reflectometry measurement.

Purpose: To present the Cooke-modified axial length (CMAL) method, which closely approximates sum-of-segments AL. Notably, sum-of-segments AL has been shown to improve predictions of many intraocular lens (IOL) power formulas; however, calculating this AL requires information that is not readily available.

Design: Comparative case series.

A comparison of two methods to calculate axial length.

Purpose: To compare prediction accuracy with the axial length (AL) calculation method of the Lenstar biometer (traditional AL) and that of the ARGOS biometer (sum-of-segments AL).

Setting: Private practice clinic.

Design: Comparative case series.

Comparison of 9 intraocular lens power calculation formulas.

Purpose: To evaluate the accuracy of 9 intraocular lens (IOL) calculation formulas using 2 optical biometers.

Setting: Private practice, Saint Joseph, Michigan, USA.

Design: Retrospective consecutive case series.

Prediction accuracy of preinstalled formulas on 2 optical biometers.

Purpose: To evaluate how well partial coherence interferometry (PCI) (IOLMaster) and optical low-coherence reflectometry (OLCR) (Lenstar LS 900) predict postoperative refractions using only the formulas that come preinstalled on the machines.

Setting: Private practice, Saint Joseph, Michigan, USA.

Design: Retrospective consecutive case series.