Regular replacement of daily-wear rigid gas-permeable contact lenses

Abstract

A prospective, single-centre, controlled, double-masked randomised study was conducted to determine the benefits, if any, of regular replacement of daily-wear rigid gas-permeable (RGP) contact lenses. Forty-one subjects, divided into two groups, wore Quantum 2 lenses (Bausch & Lomb, Rochester, New York, USA; Dk = 120) for 12 months on a daily wear basis; subjects in group I replaced lenses every 3 months, whereas those in group II were not scheduled to replace lenses. All subjects were existing RGP lens wearers without any contact lens-induced pathology (>grade 1). The integrity of the lenses and the ocular responses to lens wear were monitored in both groups every 3 months. Compared with lenses worn by subjects in group II, lenses worn by subjects in group I displayed significantly less surface drying (at 9 months), less mucus coating (at 12 months), less surface deposition (at 12 months), and less surface scratching (at 9 and 12 months) (p<0.05; ANOVA). Compared with the ocular response of subjects in group II, the ocular response of subjects in group I displayed significantly less corneal staining at 12 months (p<0.05; ANOVA). No significant differences between the groups were observed with respect to comfort, vision, or any of the other variables assessed. We advocate that, in order to maintain optimal lens integrity and ocular health, RGP lenses used for daily were should be replaced every 6 months.