This is the third episode within the BCLA CLEAR podcast series. The most fundamental aspect of a contact lens is its optics; the manner in which the refraction of light is managed to optimise vision to the clinical benefit of the lens wearer. This report presents contemporary information on the optical structure of the eye and the optical models employed to understand the correction of refractive error. The design, measurement and clinical assessment of spherical, aspheric, toric, multifocal and myopia control contact lenses are described. The complexity and variety of multifocal lenses is recognised and detailed information is provided for alternating, simultaneous, diffractive, annular, aspheric and extended depth of field lens designs. In terms of clinical assessment, a contemporary review is provided for the measurement of: visual acuity, contrast sensitivity, through focus curves, reading performance, peripheral refraction, toric displacement realignment and patient reported outcomes. Overall, the paper aims to serve as a resource for the prescribing clinician, who can optimise contact lens corrections for patients by building on the optical rationale of these devices; and also highlights future opportunities for research innovation.
Dr Kathryn Richdale is interviewed by Dr Melissa Barnett, who leads the BCLA CLEAR podcast series. Dr. Richdale is currently an attending in the Cornea and Contact Lens Service and co-director of the Myopia Management Service, and teaches in both the optometric and graduate programs at UHCO. She conducts research in the areas of cornea, contact lenses and refractive error.
Dr. Barnett is a principal optometrist at the University of California, Davis Eye Center in Sacramento and Davis, California. She is an internationally recognized key opinion leader, specializing in dry eye disease and specialty contact lenses. She is a Fellow of the American Academy of Optometry, a Fellow of the British Contact Lens Association and serves on multiple Boards. Dr. Barnett is Past President of The Scleral Lens Education Society.
BCLA CLEAR is an initiative that has drawn together thousands of research papers on many different aspects of contact lenses into one place. The findings were published in, Contact Lens and Anterior Eye, the BCLA's scientific journal, in April 2021 under ten reports. BCLA CLEAR was facilitated by the BCLA, with financial support by way of Educational Grants for collaboration, publication and dissemination provided by Alcon and CooperVision.