PURPOSE To develop a new schematic scheme for efficiently recording the key parameters of gas permeable contact lens (GP) fits based on current consensus. METHODS Over 100 established GP fitters and educators met to discuss the parameters proposed in educational material for evaluating GP fit and concluded on the key parameters that should be recorded. The accuracy and variability of evaluati...

The purpose of this study was to determine the corneal epithelial alterations induced by various types of contact lenses. By employing the specular microscope, the corneal epithelia of 60 patients who had worn contact lenses for more than 1 year were re-examined along with 15 myopic controls. The morphological changes in aphakic patients who changed from extended wear soft to extended wear rigi...

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 To evaluate comfort and visual performance in relation to two different used contact lens types: hybrid material (HM) and rigid-gas-permeable (RGP), in patients with regular myopic astigmatism and with keratoconus. METHODS A randomized, double masked, prospective study of 22 patients with the diagnosis of myopic astigmatism (8 with myopic astigmatism and 14 with keratoconus) was condu...

purpose: to determine the effect of using rigid gas permeable (rgp) contact lenses in improvement of involuntary eye movements and visual functions in hyperopic astigmatism patients with congenital nystagmus. methods: this prospective interventional case series study was conducted on patients with congenital nystagmus and hyperopia equal or more than +0.5 d and astigmatism more than -1 d, who w...

PURPOSE Based on contact lens-induced stromal acidification of the cornea, it has been suggested that the corneal epithelial and endothelial cells also become acidotic during contact lens wear. This alleged acidification may have a role in altered cell appearance and metabolism during contact lens wear. This study investigated the effects of anoxia, carbon dioxide retention, and contact lens ga...

PURPOSE To estimate the fitting parameters of the hybrid contact lens in patients with corneal ectasia using the rigid gas permeable (RGP) lens. METHODS Thirty-four eyes with corneal ectasia were evaluated in this study. The patients were examined once with the RGP lens and once with the hybrid contact lens. The relationship between the base curvature of the RGP and the vault of the hybrid le...

PURPOSE To evaluate changes in anterior corneal topography and higher-order aberrations (HOA) after 14-days of rigid gas-permeable (RGP) contact lens (CL) wear in keratoconus subjects comparing two different fitting approaches. METHODS Thirty-one keratoconus subjects (50 eyes) without previous history of CL wear were recruited for the study. Subjects were randomly fitted to either an apical-t...