Klemens Paul Kaiser, Tyll Jandewerth, Julian Bucur, Marvin Lucas Biller, Christoph Lwowski, Thomas Kohnen
{"title":"Intraocular Lens Power Calculation in Myopic Eyes Undergoing Bilensectomy: Analysis of Comparability and Accuracy.","authors":"Klemens Paul Kaiser, Tyll Jandewerth, Julian Bucur, Marvin Lucas Biller, Christoph Lwowski, Thomas Kohnen","doi":"10.1097/j.jcrs.0000000000001752","DOIUrl":"https://doi.org/10.1097/j.jcrs.0000000000001752","url":null,"abstract":"<p><strong>Purpose: </strong>To address the calculation of intraocular lens (IOL) power in myopic eyes undergoing simultaneous anterior or posterior chamber phakic IOL (pIOL) explantation and lens extraction surgery, a procedure known as bilensectomy, in comparison to myopic eyes without pIOL (controls).</p><p><strong>Design: </strong>Retrospective analysis of comparability and accuracy.</p><p><strong>Setting: </strong>Department of Ophthalmology, Goethe-University, Frankfurt, Germany.</p><p><strong>Methods: </strong>IOLMaster 700 (Zeiss Meditec AG) and Pentacam AXL (Oculus Optikgeräte GmbH) were used for biometry. IOL power was calculated using the Barrett Universal II (BUII), Cooke K6, Hoffer-QST, EVO 2.0, PEARL-DGS, Hill-RBF, and Kane formulas included in the ESCRS online calculator, as well as the T2 and Ladas super formula and the SRK/T and Holladay 1 with or without Wang-Koch axial length adjustment.</p><p><strong>Results: </strong>Sixty eyes (mean axial length: 29.1±2.06 mm) of 60 patients (mean age 57.4±10.9 years) were included. Thirty eyes underwent bilensectomy and 30 served as controls. In bilensectomy eyes, Kane (0.53 D), PEARL-DGS (0.56 D), and Hill-RBF (0.61 D) demonstrated the lowest root-mean square of the absolute error. PEARL-DGS demonstrated the highest percentage of eyes within ±0.25D (46.7%), followed by BUII, Hill-RBF, and Kane (40.0%, each). EVO 2.0 showed a significant difference (p=0.001) in mean PE between the bilensectomy group and the control group. All other formulas showed no significant differences between the two groups (each p>0.05).</p><p><strong>Conclusion: </strong>Simultaneous explantation of a pIOL does not appear to exert a considerable impact on the IOL power calculation in myopic eyes. The performance of the formulas is comparable to myopic eyes without phakic IOLs.</p>","PeriodicalId":15214,"journal":{"name":"Journal of cataract and refractive surgery","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2025-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144784316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lars H B Mackenbrock, Grzegorz Łabuz, Nikola Henningsen, Gerd U Auffarth, Ramin Khoramnia, Timur M Yildirim
{"title":"Quantitative in vivo assessment of intraocular lens calcification: correlation between OCT opacity and straylight measurement.","authors":"Lars H B Mackenbrock, Grzegorz Łabuz, Nikola Henningsen, Gerd U Auffarth, Ramin Khoramnia, Timur M Yildirim","doi":"10.1097/j.jcrs.0000000000001674","DOIUrl":"10.1097/j.jcrs.0000000000001674","url":null,"abstract":"<p><strong>Purpose: </strong>To quantitatively assess intraocular lens (IOL) calcification using anterior segment optical coherence tomography (AS-OCT) and correlate findings with straylight measurements in patients with homogenous IOL calcification.</p><p><strong>Setting: </strong>Department of Ophthalmology, Heidelberg University Hospital, Heidelberg, Germany.</p><p><strong>Design: </strong>Prospective, observational clinical study.</p><p><strong>Methods: </strong>Healthy patients with homogenous IOL calcification underwent AS-OCT imaging with the ANTERION, with IOL opacity being automatically quantified using a custom image-analysis script. Straylight was assessed using the C-Quant straylight meter. Correlation between IOL opacity and straylight was analyzed using Spearman ρ coefficient.</p><p><strong>Results: </strong>35 eyes of 35 patients (mean age 72.9 ± 7.8 years) were included. Mean IOL opacity was 69.15 ± 13.55 pixel intensity units (PIUs), and mean straylight was 2.24 ± 0.38 log(s). A statistically significant correlation was found between IOL opacity and straylight with ρ = 0.494, P = .003. After the linear regression model was established: straylight = 0.0569 × OCT opacity [log(s)] - 1.69 with R2 = 0.244. Of the 35 eyes, 17 underwent IOL exchange surgery, with a mean IOL opacity of 75.69 ± 7.58 PIU and a mean straylight of 2.33 ± 0.30 log(s).</p><p><strong>Conclusions: </strong>AS-OCT can quantitatively assess IOL calcification in vivo, with results correlating significantly with straylight measurements. This technique may serve as a valuable diagnostic tool for evaluating IOL opacification and assist in surgical decision-making, particularly in borderline cases.</p>","PeriodicalId":15214,"journal":{"name":"Journal of cataract and refractive surgery","volume":" ","pages":"666-671"},"PeriodicalIF":3.2,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143997978","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Intraocular lens power calculation accuracy after keratorefractive lenticule extraction with the novel ESCRS post-keratorefractive surgery calculator.","authors":"Lischke Roman, Wiltfang Rainer, Bechmann Martin, Kreutzer Thomas, Siegfried G Priglinger, Dirisamer Martin, Nikolaus Luft","doi":"10.1097/j.jcrs.0000000000001673","DOIUrl":"10.1097/j.jcrs.0000000000001673","url":null,"abstract":"","PeriodicalId":15214,"journal":{"name":"Journal of cataract and refractive surgery","volume":" ","pages":"740-742"},"PeriodicalIF":3.2,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144019591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Angelica Hanna, James Jacob Armstrong, Efstathia Kiatos-Tsioros, Guillermo Rocha, Cindy M L Hutnik, Iqbal Ike K Ahmed
{"title":"Intravenous vs nonintravenous sedation for cataract surgery: systematic review and meta-analysis.","authors":"Angelica Hanna, James Jacob Armstrong, Efstathia Kiatos-Tsioros, Guillermo Rocha, Cindy M L Hutnik, Iqbal Ike K Ahmed","doi":"10.1097/j.jcrs.0000000000001679","DOIUrl":"10.1097/j.jcrs.0000000000001679","url":null,"abstract":"<p><strong>Topic: </strong>This review assesses the effectiveness of intravenous (IV) sedation compared with non-IV sedation for routine cataract surgery.</p><p><strong>Clinical relevance: </strong>Cataract surgery is a safe and routinely performed surgery. Sedation practices vary, with centers providing IV, oral, or no sedation for surgery. Improving sedation practices may have significant implications for patient safety, patient experience, and health system efficiency.</p><p><strong>Methods: </strong>MEDLINE, Embase, Cochrane Library, BIOSIS, Web of Science, and CINAHL were searched from inception to July 2024 for relevant articles containing original data. Randomized controlled trials that compared IV with oral or no sedation and (1) used a validated pain scale to report on pain or (2) reported on perioperative complications were included. A random-effects meta-analysis was conducted. Odds ratios (ORs), standard mean differences (SMDs), 95% CIs, and I2 statistics were reported. The review was registered in PROSPERO (CRD42024582495), and PRISMA guidelines were followed.</p><p><strong>Results: </strong>12 randomized controlled trials including 1130 patients were included in the meta-analysis. IV sedation was associated with significantly decreased pain compared with no sedation (SMD, -0.98; 95% CI, -1.68 to -0.29). Comparing IV and oral sedation, however, there was no difference in patient-reported pain (SMD, -0.54; 95% CI, -1.60 to 0.52). Analysis of intraoperative complications showed that there was no significant difference in complications between patients receiving IV and oral sedation (OR, 0.68; 95% CI, 0.27-1.73).</p><p><strong>Conclusions: </strong>For routine cataract surgery, IV sedation was associated with less pain than no sedation, but oral and IV sedation provided comparable pain control. Perioperative complications occur at similar rates regardless of sedation modality. These findings may help to inform sedation practices for cataract surgery.</p>","PeriodicalId":15214,"journal":{"name":"Journal of cataract and refractive surgery","volume":" ","pages":"723-730"},"PeriodicalIF":3.2,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144009089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Denise Yang-Seeger, Yan Ning Neo, Oliver Findl, Akanksha Bagchi, Sjoerd Elferink, Johannes Birtel
{"title":"Perioperative practice patterns for cataract surgery: a cross-sectional European study.","authors":"Denise Yang-Seeger, Yan Ning Neo, Oliver Findl, Akanksha Bagchi, Sjoerd Elferink, Johannes Birtel","doi":"10.1097/j.jcrs.0000000000001669","DOIUrl":"10.1097/j.jcrs.0000000000001669","url":null,"abstract":"<p><strong>Purpose: </strong>To investigate pre- and postoperative visits after cataract surgery in Europe and to assess the environmental impact of patient travel.</p><p><strong>Setting: </strong>High-volume cataract centers in 16 European countries.</p><p><strong>Design: </strong>A cross-sectional survey was developed and distributed by the Young Ophthalmologists for Sustainability (YOFS), a working group of the ESCRS.</p><p><strong>Methods: </strong>Outcome measures included pre- and postoperative clinic visits, time and location of follow-ups, proportion of delayed and immediate sequential bilateral cataract surgery (DSBCS and ISBCS), and the option of remote follow-up visits.</p><p><strong>Results: </strong>In total, 89 responses were collected. Most departments performed 2000 to 5000 cataract surgeries per year. If ISBCS was offered, this accounted for less than 5% in most units. The number of preoperative visits varied between 1 (78%) and ≥3 (4%), with half of the units undertaking preoperative visits before the second-eye surgery. The number of postoperative visits ranged from 1 to 4; most centers performed 1 (35%) or 2 (45%). In total, the mean number of patient reviews was 5.7 (range, 3.3 to 9.3) for DSBCS and 3.0 (range, 2.3 to 4.0) for ISBCS. Remote follow-up visits were only offered by 6 centers.</p><p><strong>Conclusions: </strong>Large regional differences regarding the frequency of pre- and postoperative visits for cataract surgery were observed. Reducing the number of face-to-face visits may reduce costs for healthcare systems and patients, improve patient convenience, capacity, and may serve as a step toward more sustainable care by reducing travel-related carbon emissions.</p>","PeriodicalId":15214,"journal":{"name":"Journal of cataract and refractive surgery","volume":" ","pages":"647-651"},"PeriodicalIF":3.2,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143992920","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Comment on: Surgeon adoption of immediate sequential bilateral cataract surgery in the United States from 2018 to 2022.","authors":"Bharat Gurnani, Kirandeep Kaur","doi":"10.1097/j.jcrs.0000000000001704","DOIUrl":"https://doi.org/10.1097/j.jcrs.0000000000001704","url":null,"abstract":"","PeriodicalId":15214,"journal":{"name":"Journal of cataract and refractive surgery","volume":"51 8","pages":"747"},"PeriodicalIF":3.2,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145251245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Longitudinal observation of posterior capsule opacification in pediatric eyes with Marfan syndrome after in-the-bag intraocular lens implantation.","authors":"Yalei Wang, Zexu Chen, Wannan Jia, Xin Shen, Xinyao Chen, Tianhui Chen, Yang Sun, Qiuyi Huo, Yan Liu, Linghao Song, Xinyue Wang, Zhennan Zhao, Yongxiang Jiang","doi":"10.1097/j.jcrs.0000000000001677","DOIUrl":"10.1097/j.jcrs.0000000000001677","url":null,"abstract":"<p><strong>Purpose: </strong>To identify risk factors for posterior capsule opacification (PCO) after in-the-bag intraocular lens (IOL) implantation in pediatric patients with Marfan syndrome (MFS) and ectopia lentis (EL).</p><p><strong>Setting: </strong>Eye & ENT Hospital of Fudan University, Shanghai, China.</p><p><strong>Design: </strong>Prospective cohort study.</p><p><strong>Methods: </strong>This study included children who underwent in-the-bag IOL implantation, assisted by modified capsular tension ring (MCTR) or capsular tension ring and capsular hook (CTR-CH). Primary outcome was the incidence of PCO requiring Nd:YAG capsulotomy during follow-up period. Univariate and multivariate regression analyses were performed to identify influencing factors.</p><p><strong>Results: </strong>152 pediatric patients (152 eyes) were included, with a mean age at surgery of 6.32 ± 0.27 years. The incidence of PCO was 69.08% during the mean follow-up time of 2.84 ± 0.04 years. Patients with PCO had less severe EL severity ( P = .008), were more frequently implanted with AcrySof IQ IOLs compared with TECNIS IOL ( P = .002), and underwent CTR-CH implantation compared with MCTR ( P = .036). Multivariate Cox regression analysis showed that patients receiving surgery younger than 5 years old (hazard ratio [HR], 1.642, P = .019) and using AcrySof IQ IOL (HR, 1.698, P = .013) developed PCO at an earlier stage.</p><p><strong>Conclusions: </strong>PCO is a common but treatable complication after in-the-bag IOL implantation in children with MFS and EL. Patients receiving lens surgery at younger age, especially younger than 5 years old, and those implanted with AcrySof IQ IOLs, compared with TECNIS IOLs, should be informed of higher risks of developing PCO.</p>","PeriodicalId":15214,"journal":{"name":"Journal of cataract and refractive surgery","volume":" ","pages":"687-694"},"PeriodicalIF":3.2,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143985191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nan-Ji Lu, Robert Herber, Lin Wang, Ioannis M Aslanides, Jia-Qi Ai, Qin-Mei Wang, Le-Le Cui, Jos J Rozema
{"title":"Epithelial and stromal profiles of post-laser vision correction ectasia by OCT.","authors":"Nan-Ji Lu, Robert Herber, Lin Wang, Ioannis M Aslanides, Jia-Qi Ai, Qin-Mei Wang, Le-Le Cui, Jos J Rozema","doi":"10.1097/j.jcrs.0000000000001684","DOIUrl":"10.1097/j.jcrs.0000000000001684","url":null,"abstract":"<p><strong>Purpose: </strong>To investigate changes in the epithelium and stroma in patients with post-laser vision correction (LVC) ectasia using spectral-domain optical coherence tomography (SD-OCT) and to compare these changes with those observed in post-LVC stable eyes.</p><p><strong>Setting: </strong>Eye Hospital of Wenzhou Medical University, Wenzhou, China.</p><p><strong>Designs: </strong>Retrospective case-control study.</p><p><strong>Methods: </strong>Scheimpflug tomography and SD-OCT were performed on post-LVC stable and ectasia eyes. The postoperative remodeling pattern of epithelium and stroma was described. All SD-OCT machine-derived parameters were evaluated based on their receiver operating characteristic (ROC) curves, area under the curve (AUC), sensitivity, and specificity to discriminate between post-LVC stable and ectasia eyes.</p><p><strong>Results: </strong>111 eyes from 111 post-LVC stable patients (41 post-trans-photorefractive keratectomy [transPRK] eyes, 34 post-laser in situ keratomileusis [LASIK] eyes, and 36 post-small incision lenticule extraction [SMILE] eyes) and 23 eyes from 23 post-LVC ectasia patients (1 post-transPRK ectasia eye, 1 post-sub-Bowman keratomileusis ectasia eye, 1 post-laser-assisted subepithelial keratomileusis ectasia eye, and 20 post-LASIK ectasia eyes). The unique epithelium remodeling pattern was observed in both post-LVC stable and ectasia eyes, in the latter as a \"horseshoe\"-like pattern. The top 3 ranked AUC ROC SD-OCT parameters were all derived from epithelium, including epithelium 5 mm superior-inferior (cutoff value = -0.675, AUC = 0.956), epithelium 5 mm inferior (cutoff value = 52.41, AUC = 0.937), and epithelium thickness range (cutoff value = -23.685, AUC = 0.936).</p><p><strong>Conclusions: </strong>The characteristic remodeling pattern and the machine-derived SD-OCT parameters describing the epithelium remodeling of post-LVC ectasia could potentially be used for its diagnosis.</p>","PeriodicalId":15214,"journal":{"name":"Journal of cataract and refractive surgery","volume":" ","pages":"713-722"},"PeriodicalIF":3.2,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144119768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Joukje C Wanten, Maartje H M Segers, Jos Kleijnen, Noël J C Bauer, Rudy M M A Nuijts
{"title":"Efficacy of remote care in cataract surgery: systematic review.","authors":"Joukje C Wanten, Maartje H M Segers, Jos Kleijnen, Noël J C Bauer, Rudy M M A Nuijts","doi":"10.1097/j.jcrs.0000000000001652","DOIUrl":"10.1097/j.jcrs.0000000000001652","url":null,"abstract":"<p><strong>Topic: </strong>To evaluate the efficacy of currently available digital and remote care applications for postoperative cataract management compared with traditional methods for postoperative clinical measurements.</p><p><strong>Clinical relevance: </strong>With the increasing demand for ophthalmological services and an anticipated shortage of professionals, innovative approaches are needed to optimize care. Cataract surgery, characterized by its high-safety profile and turnover rate, is well-suited for digital and remote care solutions, which could enhance the postoperative patient pathway, potentially leading to substantial time and cost savings.</p><p><strong>Methods: </strong>A systematic search was performed in Ovid Embase, Ovid MEDLINE, KSR Evidence, CINAHL, and Cochrane CENTRAL Library for randomized controlled trials (RCTs) and observational studies on digital tools, telemedicine, or remote care in postoperative cataract management. Reported outcomes included patient-reported outcomes, visual acuity, refraction, intraocular pressure, slitlamp and fundus examination, or complication prevalence. The risk of bias was evaluated using the Cochrane Risk-of-Bias Assessment Tool (v. 2) and Joanna Briggs Institute Critical appraisal checklists. Data extraction included both qualitative and quantitative information. The protocol was registered at International Prospective Register of Systematic Reviews (CRD42024505933).</p><p><strong>Results: </strong>The search identified 11 319 studies of which 14 were included. These comprised 4 RCTs and 10 observational studies involving 2681 patients. Interventions were categorized into telephone consultation, messaging, automated phone calls, and mobile applications/software. Telephone consultations were effective for follow-up screening, and automated phone calls also showed promising results. Messaging was suggested to improve adherence in the early postoperative period. Visual acuity assessment tools showed potential as screening methods, but exhibited variability compared with conventional methods and had wide 95% limits of agreement. All types of interventions were well-accepted by patients.</p><p><strong>Conclusions: </strong>Early evidence supports a positive impact of implementing digital and remote care tools in the postoperative cataract management pathway, particularly for screening purposes. However, further research is needed to define their roles and develop clinical practice guidelines.</p>","PeriodicalId":15214,"journal":{"name":"Journal of cataract and refractive surgery","volume":" ","pages":"731-739"},"PeriodicalIF":3.2,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143605062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Achim Langenbucher, Peter Hoffmann, Alan Cayless, Jascha Wendelstein, Nóra Szentmáry
{"title":"Conversion of disclosed lens power formula constants.","authors":"Achim Langenbucher, Peter Hoffmann, Alan Cayless, Jascha Wendelstein, Nóra Szentmáry","doi":"10.1097/j.jcrs.0000000000001676","DOIUrl":"10.1097/j.jcrs.0000000000001676","url":null,"abstract":"<p><strong>Purpose: </strong>To present a concept for interconverting constants of disclosed lens power formulas and to simplify these conversions to linear prediction models for clinical use.</p><p><strong>Setting: </strong>Augen- und Laserklinik Castrop-Rauxel, Castrop-Rauxel, Germany.</p><p><strong>Design: </strong>Retrospective single-center case series.</p><p><strong>Methods: </strong>Analysis based on a dataset with biometric measurements of 19 472 eyes in a cataractous population performed with the IOLMaster 700. The formula constant conversion from formula A to B includes 2 steps: calculation of the lens power using formula A with variation of formula A constant and back calculation of the constant for formula B for all constant values of formula A using nonlinear iterative optimization techniques to minimize the sum of squared formula B prediction error.</p><p><strong>Results: </strong>Formula conversion was calculated for the SRK/T A-constant (A = 117 to 121), Hoffer Q (pACD = 4.2 to 6.8), Holladay 1 (SF 0.5 to 3.0), Haigis (a0 0.0 to 2.5 with a1/a2 = 0.4/0.1), and Castrop (C 0.15 to 0.50 with H/R = 0.0) formulas. As the conversions follow linear dependencies, linear regression models were fitted to simplify formula constant conversions in clinical routine.</p><p><strong>Conclusions: </strong>Conversions of formula constants could be used in cases where, for example, new lens models are launched with only the nominal SRK/T A-constant available or in situations where constants for some of the formulas are not available. Conversions to constant triplets for the Haigis or Castrop formula require additional nonlinear boundary conditions to take full advantage of formulas with multiple constants.</p>","PeriodicalId":15214,"journal":{"name":"Journal of cataract and refractive surgery","volume":" ","pages":"679-686"},"PeriodicalIF":3.2,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144016203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}