The influence of contact lens wear on the corneal response to ultraviolet radiation.

One eye of each of 15 male pigmented rabbits was fitted with a gas-permeable rigid contact lens. Lenses were worn on a daily basis for an initial period of 7 days with the other eye serving as a control. After this initial period the lenses were removed and both eyes were irradiated with UV-B (305 nm +/- 9 full width half maximum) using either 0.03 J cm-2 or 0.12 J cm-2 which were approximately the epithelial and endothelial damage thresholds for this waveband respectively. The responses of the cornea were followed by microscopy and pachometry. Biomicroscopically there was a dramatic difference in response between contact lens wearing and non-wearing eyes for the higher radiant exposure, whereas little difference was observed at the lower level. For both levels of radiant exposure there was a significantly less corneal thickness increase in contact lens wearing eyes after UV-B irradiation. Recovery patterns were similar.