This study presents a comprehensive method for designing a multifocal contact lens (MCL) with Snell's law and non-uniform rational B-spline (NURBS) curves. Instead of using thin lens approximation, general mathematical formulas have been developed to achieve the accurate coordinates of points on the anterior lens surface profile of the MCL to meet various given optical power distributions. Then the NURBS curve is adjusted to fit these data points to obtain the smooth front lens surface profile. This method not only improves the accuracy of the optical power profiles of MCLs but also reduces the spherical aberration in near/distance optical zones. The experimental results show that the power profiles of soft MCLs agree with those of the simulation results and original design requirements. The proposed method has been proven for the MCL design, and it can be feasibly applied in complex optical lens designs.
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http://dx.doi.org/10.1364/AO.451952 | DOI Listing |
Healthcare (Basel)
January 2025
Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, Shanghai 200031, China.
This study aimed to analyze the research progress on the use of a multifocal lens for myopic control throughout the 21st century, utilizing bibliometric analysis. Publications related to multifocal lenses from 2001 to 2024 were searched on the Web of Science core collection (WoSCC) database. VOSviewer (Version 1.
View Article and Find Full Text PDFImportance: For myopia control to be beneficial, it would be important that the benefit of treatment (slowed eye growth) is not lost because of faster than normal growth (rebound) after discontinuing treatment.
Objective: To determine whether there is a loss of treatment effect (rebound) after discontinuing soft multifocal contact lenses in children with myopia.
Design, Setting, And Participants: The Bifocal Lenses in Nearsighted Kids 2 (BLINK2) cohort study involved children with myopia (aged 11-17 years at BLINK2 baseline) who completed the BLINK Study randomized clinical trial.
Clin Exp Optom
January 2025
Eurolens Research, Division of Pharmacy and Optometry, The University of Manchester, Manchester, UK.
Clinical Relevance: Knowledge of contact lens prescribing trends can (a) assist practitioners to benchmark their own prescribing habits, (b) help the contact lens industry understand preferred products, and (c) support academics in scholarly writings.
Background: This work aims to document contact lens prescribing trends in Australia over the past quarter of a century.
Methods: An annual survey of contact lens prescribing trends was conducted in Australia each year from 2000 to 2024, inclusive, by asking optometrists to provide information relating to 10 consecutive contact lens fits undertaken between January and March.
Eye Contact Lens
November 2024
Department of Optics, Pharmacology and Anatomy (K.J.M.-G., D.F., D.P.P.), University of Alicante, Alicante, Spain; and Advanced Clinic Optometry Unit (D.P.P.), Department of Ophthalmology, Medimar International Hospital, Alicante, Spain.
Purpose: To investigate the impact on distance and near contrast sensitivity (CS) after fitting multifocal contact lenses (MFCLs) for presbyopia correction according to the scientific evidence already published.
Methods: Three bibliographic search was conducted on PubMed, Web of Sciences, and Scopus. Inclusion criteria were articles written in English evaluating distance and/or near CS in presbyopic patients using MFCLs, controlled clinical trials, and articles published from 2000 to 2024.
Clin Breast Cancer
December 2024
Hospital Universitario de Bellvitge, Gynecology, Hospitalet de Llobregat, Barcelona, Spain.
Purpose: To validate the Axillary Reverse Mapping (ARM) technique with indocyanine green (ICG), focusing on the detection rate and the procedure's feasibility. The predictive factors for metastatic involvement of ARM nodes are also analyzed to define the target population for ARM indication.
Methods: This prospective, observational, non-randomized study of patients with breast cancer included patients with an indication for axillary lymph node dissection (ALND) performed between June 2021 and June 2023.
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