PURPOSE To investigate thickness profile changes of the corneal epithelium and Bowman's layer at the vertical and horizontal meridians with overnight myopia orthokeratology (OK) lenses. METHODS Twenty subjects (age range: 19-33 years) wore reverse-geometry rigid gas-permeable OK lenses in both eyes for 30 days. Before lens wear and after 1, 7, and 30 days of overnight lens wear, evaluation of...

BACKGROUND Most corneal damage induced by contact lenses is due to interference with corneal oxygenation. OBJECTIVE To investigate the effect on the rabbit cornea of a rigid gas-permeable contact lens with a newly designed periphery. METHOD We fitted New Zealand white rabbits (n = 12) with RGP contact lenses that were identical in all respects except for the design of the periphery. In each...

This study compared tear function tests and cytologic changes on the conjunctival surface in asymptomatic patients wearing contact lens of different materials. Included in this study were 40 eyes wearing daily wear 4 week replacement hydrogel (H) lenses, 32 eyes wearing silicone hydrogel (SiH) lenses, 18 eyes wearing rigid gas-permeable (RGP) lenses, and 21 healthy eyes (no lenses) as the contr...

PURPOSE This study investigated short-term corneal changes induced by reverse-geometry lenses worn for orthokeratology. METHODS Nine young adult subjects wore reverse-geometry rigid gas-permeable lenses (BE; UltraVision Contact Lenses, Brisbane, Australia) in one eye only for 10, 30, and 60 min in the open eye and 8 h in the closed eye. The fellow eye acted as a non-lens-wearing control. Corn...

BACKGROUND This study aimed to evaluate anterior segment spectral optical coherence tomography (AS SOCT) for assessing the lens-to-cornea fit of rigid gas-permeable (RGP) lenses. The results were verified with the fluorescein pattern method, considered the criterion standard for RGP lens alignment evaluations. MATERIAL AND METHODS Twenty-six eyes of 14 patients were enrolled in the study. Ini...

BACKGROUND The aim of this study is to analyze the relationship between the self-reported symptoms and objective signs of dry eye disease in long-term rigid gas-permeable (RGP) or soft contact lens (SCL) wearers. SUBJECTS AND METHODS The study included 84 eyes of Caucasian RGP and SCL wearers between the age of 15 and 71 who wore contact lenses on a continuous daily basis for more than 1 year...

PURPOSE To examine the optimum time at which fluorescein patterns of gas permeable lenses (GPs) should be evaluated. METHODS Aligned, 0.2mm steep and 0.2mm flat GPs were fitted to 17 patients (aged 20.6 ± 1.1 years, 10 male). Fluorescein was applied to their upper temporal bulbar conjunctiva with a moistened fluorescein strip. Digital slit lamp images (CSO, Italy) at 10× magnification of the ...