2020–2021 BCSC Basic and Clinical Science Course™
3 Clinical Optics
Chapter 6: Intraocular Lenses
Intraocular Lens Power Calculation After Corneal Refractive Surgery
Except for the Haigis formula, all the modern IOL power formulas (eg, Hoffer Q, Holladay 1 and 2, and SRK/T) use the AL values and K readings to predict the postoperative position of the IOL (ELP). The flatter-than-normal K value for eyes that have undergone myopic refractive surgery causes an error in this prediction because the anterior chamber dimensions do not actually change in these eyes commensurately with the much flatter K. These ELP errors also tend to result in hyperopic refractive surprise.
Excerpted from BCSC 2020-2021 series : Section 3 - Clinical Optics. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.