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Jafarinasab M-R, Hassanpour K, Khosravi B, Esfandiari H, Hooshmandi S. A Modified Formula for Intraocular Lens Power Calculation Based on Aphakic Refraction in a Pediatric Population. JOVR [Internet]. 2023Feb.13 [cited 2024May3];18(1):34–40. Available from: https://knepublishing.com/index.php/JOVR/article/view/12723

https://doi.org/10.18502/jovr.v18i1.12723

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authors

  • Mohammad-Reza Jafarinasab

    Mohammad-Reza Jafarinasab

    Ophthalmic Epidemiology Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran, Iran
  • Kiana Hassanpour

    Kiana Hassanpour

    MD, MPH. Ophthalmic Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Paidarfard St., Boostan 9th St., Pasdaran, Ave., Tehran 16666, Iran
  • Behrooz Khosravi

    Behrooz Khosravi

    Ophthalmic Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran, Iran
  • Hamed Esfandiari

    Hamed Esfandiari

    Ophthalmic Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran, Iran
  • Sadid Hooshmandi

    Sadid Hooshmandi

    Ophthalmic Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran, Iran

Published Date

  • Feb 13, 2023
This journal is publishing all the articles under Creative Commons Attribution License CC BY 4.0.

A Modified Formula for Intraocular Lens Power Calculation Based on Aphakic Refraction in a Pediatric Population

Journal of Ophthalmic and Vision Research (JOVR) / Jan–Mar 2023, Volume 18, Issue 1 / Pages 34–40

Abstract

Purpose: To investigate and optimize the accuracy of aphakic refraction (AR) techniques for secondary intraocular lens (IOL) power calculation in aphakic children.
Methods: Thirty-three aphakic eyes of 18 patients who were candidates for secondary IOL implantation were enrolled in the present study. Axial length (AL) measured by optical biometry was used in the biometric formula (SRK-T, Holladay II, and Hoffer-Q). AR and spherical equivalent (SE) were used in two AR-based formulas (Ianchulev, Leccissotti). True power was calculated based on postoperative SE at three months’ follow-up.
Results: Regarding the postoperative SE, 13 (40%) eyes were within ±1.00 diopters (D) and 22 (66%) were within ±2.00 D. Median absolute error (MedAE) was predicted to be 4.4 and 7.3 D with the use of Ianchulev and Leccissotti formulas, respectively. The corresponding value was 0.8 D with the biometric formula. All eyes were deemed to have myopic refraction when using the AR-based formulas except one eye with the Ianchulev formula. The coefficient of our modified formula was 1.7 instead of 2.01 in the Ianchulev formula. MedAE with the use of new formulae was 0.5 D and was comparable with the true IOL power (P = 0.22).
Conclusion: Both Ianchulev and Leccissotti formulas resulted in a significant myopic surprise in aphakic children aged between 4.5 and 14 years. The modified formula proved to determine a more accurate SE that is comparable with biometric formulas.

Keywords:

Aphakic Refraction, Intraocular Lens (IOL), IOL Power Calculation, Pediatric Cataract

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