Klemens Paul Kaiser, Tyll Jandewerth, Joukje C Wanten, Christoph Lwowski, Mariam Sobhi, Rudy M M A Nuijts, Thomas Kohnen
{"title":"Barrett RX tool for intraocular lens power calculation in pseudophakic eyes undergoing intraocular lens exchange.","authors":"Klemens Paul Kaiser, Tyll Jandewerth, Joukje C Wanten, Christoph Lwowski, Mariam Sobhi, Rudy M M A Nuijts, Thomas Kohnen","doi":"10.1097/j.jcrs.0000000000001732","DOIUrl":null,"url":null,"abstract":"<p><strong>Purpose: </strong>To assess the accuracy of refraction prediction after intraocular lens (IOL) exchange using a software integrated in a Scheimpflug-based biometer.</p><p><strong>Setting: </strong>Two tertiary referral hospitals.</p><p><strong>Design: </strong>A first case series.</p><p><strong>Methods: </strong>Eyes that underwent uneventful bag-to-bag IOL exchange between 2017 and 2024 and complete pre- and postoperative measurements were included. IOL exchange was performed by two experienced surgeons. IOL power was calculated using the Barrett RX formula integrated in Pentacam software (Oculus Optikgeräte GmbH, Wetzlar, Germany), incorporating both phakic and pseudophakic biometric data and subjective refraction. Prediction errors were computed by comparing actual postoperative and predicted refractions. Moreover, a unpublished estimation formula was applied.</p><p><strong>Results: </strong>Twenty-five eyes of 25 patients (mean age 60.2±11.4 years) were included. Mean interval between primary IOL implantation and exchange was 25.3±31.5 weeks. In 11/25 eyes, a different IOL model was implanted during the exchange. Using the Barrett RX formula, the mean prediction error (MPE) was 0.02±0.32D, mean absolute error (MAE) 0.27±0.17D, and median absolute error (MedAE) 0.22D. A total of 56% and 92% of eyes were within ±0.25D and ±0.50D of target refraction, respectively. The conventional formula yielded a comparable MPE of -0.12±0.68D (p=0.479), but higher MAE and MedAE (0.53±0.42D and 0.40D, p<0.001), with 32% and 56% of eyes within ±0.25D and ±0.50D, respectively.</p><p><strong>Conclusion: </strong>The Barrett RX formula has been demonstrated to be an efficacious method for calculating IOL power in eyes undergoing IOL exchange, with more than half of cases within ±0.25D of the predicted post-exchange refraction.</p>","PeriodicalId":15214,"journal":{"name":"Journal of cataract and refractive surgery","volume":" ","pages":""},"PeriodicalIF":2.6000,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of cataract and refractive surgery","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1097/j.jcrs.0000000000001732","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"OPHTHALMOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Purpose: To assess the accuracy of refraction prediction after intraocular lens (IOL) exchange using a software integrated in a Scheimpflug-based biometer.
Setting: Two tertiary referral hospitals.
Design: A first case series.
Methods: Eyes that underwent uneventful bag-to-bag IOL exchange between 2017 and 2024 and complete pre- and postoperative measurements were included. IOL exchange was performed by two experienced surgeons. IOL power was calculated using the Barrett RX formula integrated in Pentacam software (Oculus Optikgeräte GmbH, Wetzlar, Germany), incorporating both phakic and pseudophakic biometric data and subjective refraction. Prediction errors were computed by comparing actual postoperative and predicted refractions. Moreover, a unpublished estimation formula was applied.
Results: Twenty-five eyes of 25 patients (mean age 60.2±11.4 years) were included. Mean interval between primary IOL implantation and exchange was 25.3±31.5 weeks. In 11/25 eyes, a different IOL model was implanted during the exchange. Using the Barrett RX formula, the mean prediction error (MPE) was 0.02±0.32D, mean absolute error (MAE) 0.27±0.17D, and median absolute error (MedAE) 0.22D. A total of 56% and 92% of eyes were within ±0.25D and ±0.50D of target refraction, respectively. The conventional formula yielded a comparable MPE of -0.12±0.68D (p=0.479), but higher MAE and MedAE (0.53±0.42D and 0.40D, p<0.001), with 32% and 56% of eyes within ±0.25D and ±0.50D, respectively.
Conclusion: The Barrett RX formula has been demonstrated to be an efficacious method for calculating IOL power in eyes undergoing IOL exchange, with more than half of cases within ±0.25D of the predicted post-exchange refraction.
期刊介绍:
The Journal of Cataract & Refractive Surgery (JCRS), a preeminent peer-reviewed monthly ophthalmology publication, is the official journal of the American Society of Cataract and Refractive Surgery (ASCRS) and the European Society of Cataract and Refractive Surgeons (ESCRS).
JCRS publishes high quality articles on all aspects of anterior segment surgery. In addition to original clinical studies, the journal features a consultation section, practical techniques, important cases, and reviews as well as basic science articles.