Intraocular lens power calculation in patients with irregular astigmatism

Asaf Achiron*, Omar Elhaddad, Duncan Leadbetter, Eliya Levinger, Oleksiy Voytsekhivskyy, Katy Smith, Venkata Avadhanam, Kieren Darcy, Derek Tole

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

1 Scopus citations

Abstract

Purpose: Accurate intraocular lens (IOL) calculation in subjects with irregular astigmatism is challenging. This study evaluated the accuracy of using Scheimpflug-derived central 2-mm equivalent keratometry reading (EKR) values for IOL calculation in irregular astigmatism. Methods: This retrospective study included subjects (31 eyes of 30 patients) who underwent cataract surgery and IOL calculation using the 2-mm central EKR methods. We compared prediction error (PE) and absolute PE (APE) outcomes using SRK/T and Barrett Universal II formulas for keratometry data obtained from the IOLMaster 500 and Pentacam (anterior corneal sim k) devices. Results: Cataract surgery and IOL calculation using the 2-mm central EKR methods resulted in improved visual acuity (uncorrected: from 1.13 ± 0.38 to 0.65 ± 0.46 logMar, p < 0.01; best-corrected: from 0.45 ± 0.24 to 0.26 ± 0.20 logMar, p < 0.01) after surgery. The percentage of subjects with best-corrected visual acuity of 6/6 was 22%, < 6/9 was 58%, and < 6/12 was 71%. For both the SRK/T and the Barrett formulas, the PE was similar to those obtained by IOLMaster (> 0.14) but lower than those obtained by the anterior corneal sim k (p < 0.02). IOLMaster provided keratometry reading in only 23/31 (74.1%) of cases. Conclusions: The use of Scheimpflug central 2-mm EKR for IOL calculation in irregular astigmatism was beneficial in terms of visual acuity improvement. It had comparable refractive prediction performance to the IOLMaster 500 and better than the anterior corneal sim K. The 2-mm EKR method can be used when IOLMaster cannot provide a reliable reading in abnormal corneas.

Original languageEnglish
Pages (from-to)3889-3895
Number of pages7
JournalGraefe's Archive for Clinical and Experimental Ophthalmology
Volume260
Issue number12
DOIs
StatePublished - Dec 2022

Funding

FundersFunder number
Porter School of Environmental Studies, Tel Aviv University
Tel Aviv University
Claire and Amédée Maratier Institute for the Study of Blindness and Visual Disorders, Tel Aviv University
Center for Nanoscience and Nanotechnology, Tel Aviv University
Adams Super Center for Brain Studies,Tel Aviv University
Cancer Biology Research Center, Tel Aviv University
Varda and Boaz Dotan Research Center for Hemato-Oncology Research, Tel Aviv University
Manna Center for Plant Biosciences, Tel Aviv University
Sagol School of Neuroscience, Tel Aviv University

    Keywords

    • Calculation
    • Cataract
    • IOL
    • Keratometry
    • Scheimpflug central 2 mm

    Fingerprint

    Dive into the research topics of 'Intraocular lens power calculation in patients with irregular astigmatism'. Together they form a unique fingerprint.

    Cite this