PURPOSE: To describe the incidence of contact lens associated papillary conjunctivitis (CLPC) in subjects wearing low Dk and silicone hydrogel contact lenses (CL) extended wear (EW); and to determine the recurrence rate of CLPC in silicone hydrogel CL EW.
METHODS: In retrospective clinical trials at both Australia and India from 1993 to 2003, 1,894 subjects wore either low-Dk hydrogel CL on a 6 night (N) or silicone hydrogel CL on either a 6 N or 30N EW schedule. The incidence of CLPC per 100 eye years (%) for each lens type was determined for first events only. CLPC was classified by location of papillae. Papillae confined to 2 areas of the tarsal conjunctiva were classified as local and papillae spread over more than 2 areas were classified as general. Fisher’s Exact Test assessed differences between the two groups.
RESULTS: The incidence of CLPC in low-Dk CL wearers was 3.9 per 100 eye years (95% CI = 2.9 – 5.0) and in silicone hydrogel CL wearers 5.2 per 100 eye years (95% CI = 4.3 – 6.2). There was a significantly greater incidence of local CLPC events compared to general events in silicone hydrogel CL (3.6% vs. 0.7%, p<0.0001) and a significantly greater incidence of general CLPC in low Dk hydrogel CL compared to local CLPC events (3.4% vs. 1.7%, p=0.003). 63% of all eyes had a recurrence of CLPC. 28% of eyes with prior CLPC events recurred as a general event and 49% of eyes recurred as a local event with silicone hydrogel CL wear.
CONCLUSIONS: The incidence of local CLPC is higher in silicone hydrogel CL wear than in low-Dk CL wear. This difference in incidence between local and general CLPC events may be caused by different mechanisms. At least 60% of eyes will have a recurrence of a CLPC event with silicone hydrogel EW.
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