Jafarinasab MR, Khosravi B, Esfandiari H, Hooshmandi S, Hassanpour K. A Modified Formula for Intraocular Lens Power Calculation Based on Aphakic Refraction in a Pediatric Population.
J Ophthalmic Vis Res 2023;
18:34-40. [PMID:
36937190 PMCID:
PMC10020791 DOI:
10.18502/jovr.v18i1.12723]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 09/14/2022] [Indexed: 02/24/2023] Open
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.
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