Comparison of the number of visits and diagnostic lenses required to fit RGP, conventional hydrogel and silicone hydrogel contact lenses

Abstract

Purpose To describe differences in the number of visits and in the number of diagnostic lenses (DL) necessary to fit rigid gas permeable (RGP), traditional hydrogel and silicone hydrogel contact lenses (CL) in non-pathological eyes. Methods Retrospective analysis of 196 refractive or cosmetic CL fittings (Optometry Unit, IOBA Eye Institute). Only daily wearers of CL were included. Patients with ocular pathology, orthokeratology, etc. were excluded. Results Of all CL fitted, 21 % were RGP, 51 % were traditional hydrogel CL and 28 % were silicone hydrogel. RGP required slightly more visits (median 4, range 2–6; p < 0.001 ANOVA Kruskal-Wallis) when compared to traditional (median 3, range 2–5) and silicone hydrogel CLs (median 3, range 2–5). No differences were found (p > 0.05 ANOVA Kruskal-Wallis) between new and previous wearers. RPG requires more DL (median 3, range 1–5; p < 0.001 ANOVA Kruskal-Wallis) when compared to traditional (median 2, range 1–4) or silicone (median 2, range 1–4) hydrogel CLs. No differences in visits (p = 0.31 ANOVA Kruskal-Wallis) and DL (p = 0.65 ANOVA Kruskal-Wallis) were found between traditional and silicone hydrogel lenses. Conclusions RGP fitting requires slightly more visits and DL than fitting of traditional or silicone hydrogel CL. No difference in the number of visits and DL required between traditional and silicone hydrogel CL were found. An estimated three to four visits could be necessary to fit daily wear CL in non-pathological eyes. This clinical evidence (grade IV) could be used to improve the clinical guidelines for fitting and care of patients with CL.