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Refractive predictive errors using Barrett II, Hoffer-Q, and SRKT formulae for pediatric IOL implantation
Or Shmueli1, Nur Azem1, Ana Navarrete1
1Department of Ophthalmology, Hadassah Medical Center, The Hebrew University of Jerusalem, 9112001, Ein-Karem, Jerusalem, Israel.
Insights
The Barrett II universal (BU II) formula showed good accuracy for pediatric intraocular lens (IOL) calculations. While overall differences were not significant, BU II demonstrated stable prediction error across various axial lengths, ages, and keratometry readings.
Area of Science:
- Ophthalmology
- Pediatric Ophthalmology
- Biomedical Engineering
Background:
- Accurate intraocular lens (IOL) power calculation is crucial for visual outcomes in pediatric patients undergoing lensectomy.
- Existing IOL calculation formulas may have varying accuracy in the unique biometric environment of a developing pediatric eye.
Purpose of the Study:
- To compare the refractive prediction accuracy of three common IOL calculation formulas: Barrett II universal (BU II), Hoffer-Q, and SRKT.
- To evaluate formula performance across different pediatric subgroups based on age, axial length, and keratometry.
Main Methods:
- Retrospective analysis of 151 eyes from 104 children who had lensectomy and IOL implantation between 2015 and 2023.
- Comparison of mean prediction error (PE) and absolute PE < 1.0 D for BU II, Hoffer-Q, and SRKT formulas.
- Subgroup analysis based on axial length (<22 mm vs. ≥22 mm), age at surgery (≥24 months vs. younger), and mean keratometry (≥44.5 D).
Main Results:
- The Barrett II universal (BU II) formula demonstrated a low mean prediction error (-0.08 ± 1.54 D).
- BU II showed a smaller prediction error than SRKT in eyes with axial length < 22 mm and a smaller error than Hoffer-Q in eyes with axial length ≥ 22 mm.
- BU II achieved an absolute prediction error < 1.0 D in 66% of eyes, significantly higher than SRKT (35%).
Conclusions:
- The Barrett II universal (BU II) formula is a reliable and stable option for pediatric IOL calculations.
- BU II exhibits consistent accuracy across a range of pediatric biometric parameters, including varying axial lengths, keratometry readings, and patient ages.
- The formula's stability makes it suitable for the dynamic changes in the pediatric eye during growth.
Purpose:
To compare the accuracy of the Barrett II universal (BU II) formula, Hoffer-Q, and SRKT formulae following lensectomy and IOL implantation in a large pediatric cohort.
Methods:
Retrospective study of children who underwent lensectomy and IOL implantation between 2015 and 2023 at Hadassah-Hebrew University Medical Center, Jerusalem, Israel.
Results:
One hundred and fifty-one eyes of 104 children aged 6.0 ± 3.9 years were included. The mean prediction error (PE) was - 0.08 ± 1.54 diopters (D) with BU II, 0.24 ± 1.46 D with Hoffer-Q, and 0.71 ± 1.92 D with SRKT (P = 0.10). In eyes with axial length (AL) < 22 mm, BU II and Hoffer-Q had a smaller PE than SRKT (P = 0.024). In eyes with AL ≥ 22 mm, BU II had a smaller PE than Hoffer-Q (P = 0.048). In children 24 months or older at surgery, BU II had a smaller PE than SRKT and Hoffer-Q (P = 0.012). However, in younger children, no difference was found between the formulae (P = 0.61). For mean k-values ≥ 44.5 D, BU II and Hoffer-Q had a smaller PE than SRKT (P = 0.002). An absolute prediction error < 1.0 D was obtained with BU II in 66% of eyes and SRKT in 35% (P = 0.01).
Conclusions:
The BU II formula performed well with a small prediction error. No significant difference in PE was detected overall between the formulae. However, only BU II demonstrated a stable prediction error at varying axial lengths, K-readings, and ages. As the biometric parameters of the developing eye change with growth, the BU II formula offers a reliable and stable option for pediatric IOL calculation.
