Refining Iol Power Calculations With Pmod: A Multi-Formula Analysis In High-Power Lenses
Published 2026 - 44th Congress of the ESCRS
Reference: POCAT605 | Type: Free paper | DOI: 10.82333/fmw4-7d78
Authors: Dr Yea Eun Lee 1 , Dr Chung Min Lee 1 , Dr Nahyun Park 1 , Ms Jeewon Han 1 , Dr So Hyun Yu 2 , Dr Sang Yoon Kim 2 , Dr Cecily L. Kaufmann 3 , Dr Myung-Sun Song 1 , Dr Tae Hun Kim 1 , Dr Tae Yeon Kim 1 , Dr Kyu Sang Eah 1 , Prof. Dr Ho Seok Chung 1 , Prof. Dr Jae Yong Kim 1 , Dr Kyung Min Koh 2 , Dr David L. Cooke 4 , Prof. Dr Hun Lee* 5
1Ophthalmology,Asan Medical Center, University of Ulsan College of Medicine,Seoul,Korea, Republic Of, 2Ophthalmology,Kim's Eye Hospital,Seoul,Korea, Republic Of, 3Ophthalmology,University of South Carolina School of Medicine,Columbia,United States, 4Great Lakes Eye Care,Saint Joseph,United States;Department of Neurology and Ophthalmology, School of Osteopathic Medicine, Michigan State University,East Lansing,United States, 5Ophthalmology,Asan Medical Center, University of Ulsan College of Medicine,Seoul,Korea, Republic Of;Ophthalmology,Brain Korea 21 project, University of Ulsan College of Medicine,Seoul,Korea, Republic Of;Center for Cell Therapy, Asan Medical Center,Seoul,Korea, Republic Of
Purpose
To evaluate the effectiveness of prediction modifications (PMOD) in improving refractive accuracy of modern intraocular lens (IOL) formulas in high-power TECNIS IOLs.
Setting
Single center, Republic of Korea
Methods
This retrospective study included 645 eyes (497 patients) implanted with TECNIS ZCB00 or ICB00 IOLs. Eyes were stratified into central power (17.5–23.5 D) and high-power (>23.5 D) groups. Formula constants were optimized using the central power group and applied to both groups. PMOD, based on prior large-scale regression data, were applied to the high-power group. Twelve IOL power formulas were evaluated before and after PMOD application. Prediction errors were analyzed using mean refractive error (MRE), mean absolute error (MAE), and root mean square absolute error (RMSAE) with the Wilcox-Holladay-Wang-Koch (WHWK) method.
Results
In the high-power group, eyes exhibited significantly shorter axial length, shallower anterior chamber depth, and greater lens thickness (all P<0.001). All formulas including Barrett Universal II, Cooke K6, EVO 2.0, Haigis, Hoffer QST, Holladay 1, Holladay 2 with nonlinear regression (H2 NLR), Kane, Olsen, PEARL-DGS, SRK/T, and T2 achieved -0.01–0.01 D MRE after optimization in the central power (17.5–23.5 D) group. In the high-power (>23.5 D) group, PMOD effectively corrected the myopic shift, significantly reducing MRE, MAE, and RMSAE across all formulas (all P<0.05), except for MAE in PEARL-DGS (P=0.050).
Conclusions
PMOD is a simple diopter-specific adjustment applied to the formula-predicted spherical equivalent. It effectively improved refractive prediction accuracy and reduced residual systematic errors that persisted in high-power IOLs across formulas, even after applying constants optimized in the central power group