Conjunctival impression cytology in contact lens wearers.

ABSTRACT

PURPOSE: To evaluate the cytological changes in conjunctiva following regular contact lens wear and to determine the correlation, if any, between severity of cytological alteration and symptoms related to contact lens wear. METHODS: One hundred eyes (50 normal asymptomatic subjects) who served as a control group were studied by conjunctival impression cytology (CIC). These subjects were fitted with rigid gas permeable (RGP) or soft contact lenses and were followed up at the end of 3 and 6 months. At each follow-up visit the CIC was repeated. A filter paper with the impression specimen was stained with periodic acid schiff (PAS) and haematoxylin stain to study goblet cell loss. Papanicolaou stain was done to study squamous metaplasia. The cytological changes were graded using the system described by Natadisastra et al. RESULTS: Severity of cytological changes increased with the duration of contact lens wear (P = 0.00001). At the end of 6 months, 60% of symptomatic eyes wearing soft contact lens and RGP lens showed abnormal CIC changes. None of the asymptomatic RGP contact lens wearing eyes showed abnormal CIC changes whereas 33.4% of the asymptomatic soft contact lens wearing eyes showed abnormal CIC changes (P = 0.033). Epithelial changes occurred within 3-6 months of contact lens fitting. CONCLUSION: Severity of cytological changes increased with duration of lens wear (P = 0.00001). Prevalence and severity of cytological alteration is more in symptomatic contact lens wearers. Soft contact lens wearers although asymptomatic showed severe CIC changes.