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New web-based algorithm to improve rigid gas permeable contact lens fitting in keratoconus.
Sara Ortiz-Toquero1, Guadalupe Rodriguez1, Victoria de Juan2
1Universidad de Valladolid, Departamento de Física Teórica, Atómica y Óptica, Paseo de Belén, 7 - Campus Miguel Delibes, 47011 Valladolid, Spain; Universidad de Valladolid, Instituto Universitario de Oftalmobiología Aplicada (IOBA), Paseo de Belén, 17 - Campus Miguel Delibes, 47011 Valladolid, Spain; Optometry Research Group, IOBA Eye Institute, School of Optometry, University of Valladolid, Valladolid, Spain.
A new web-based algorithm accurately selects the back optic zone radius for gas permeable lenses in keratoconus eyes. This tool improves fitting efficiency and reduces chair time for practitioners and patients.
Area of Science:
- Ophthalmology
- Optometry
- Biomedical Engineering
Background:
- Keratoconus management often requires specialized gas permeable (GP) lens designs.
- Accurate selection of the back optic zone radius (BOZR) is crucial for optimal GP lens fitting in keratoconus.
- Existing methods for BOZR selection may lack precision, leading to prolonged fitting times.
Purpose of the Study:
- To develop and validate a novel web-based algorithm for determining the BOZR of spherical GP lenses in keratoconus.
- To compare the performance of the new algorithm against manufacturer guidelines and existing software (APEX).
Main Methods:
- A retrospective analysis (n=35) and prospective validation (n=50) of the new BOZR algorithm were performed on keratoconus eyes.
- The algorithm's calculated BOZR was compared to the finally prescribed BOZR.
- Fitting metrics including diagnostic lenses, ordered lenses, and visits were recorded and compared to a control group of healthy eyes.
Main Results:
- The new algorithm demonstrated a strong correlation with the final prescribed BOZR (r²=0.825, p<0.001).
- The algorithm's initial diagnostic lens BOZR showed significantly less deviation from the final fit compared to manufacturer guidelines and APEX software.
- Similar numbers of diagnostic lenses, ordered lenses, and patient visits were required for fitting keratoconus eyes with the new algorithm compared to healthy eyes.
Conclusions:
- The validated web-based algorithm enhances the fitting of spherical KAKC GP lenses in keratoconus.
- This tool can decrease chair time for both practitioners and patients seeking an optimal lens fit.
- The algorithm helps standardize GP lens fitting for keratoconus, aligning it more closely with fittings for healthy eyes.
