EFFECT OF PATIENT WEAR AND EXTENT OF PROTEIN DEPOSITION ON ADSORPTIONOF ACANTHAMOEBA TO 5 TYPES OF HYDROGEL CONTACT-LENSES

Attachment of Acanthamoeba species to hydrogel contact lenses is a pos sible route of infection in Acanthamoeba keratitis. In this study, Aca nthamoeba adsorption was compared with extent of lens deposition in wo rn lenses of different hydrogel polymers. After wear, lenses (80 lense s of 5 different types) were analyzed for total protein, surface area of deposition, and Acanthamoeba castellani trophozoite and cyst adsorp tion. Adsorption of Acanthamoeba trophozoites to worn lenses was great er than adsorption to unworn lenses for four of the five lens polymers (p < 0.01). Adsorption of cysts was greater for one of the five lens polymers (p < 0.001); all other adsorption assays showed no change wit h wear (p > 0.05). Adsorption was affected by both the water content a nd ionicity of the lens polymer. These results show that adsorption of Acanthamoeba to worn hydrogel contact lenses is greater than or equal to adsorption to unworn lenses.