MORPHOLOGICAL-CHANGES OF THE CONJUNCTIVAL EPITHELIUM IN CONTACT-LENS WEARERS EVALUATED BY IMPRESSION CYTOLOGY

Purpose Conjunctival changes induced by rigid, gas-permeable and soft contact lenses (CL) were investigated using impression cytology. A sco ring system based on seven parameters (specimen cellularity, cell-to-c ell contacts, nucleus/cytoplasm ratio, chromatin, goblet cell distribu tion, keratinisation, inflammatory cells) was used to evaluate the mor phological results. Methods One hundred and seventy-two CL-wearing eye s and 40 control eyes were examined. The population was divided into t hree groups: group 1, control eyes; group 2, asymptomatic CL-wearing e yes; group 3, CL-wearing eyes with intolerance problems. Impression cy tology was carried out and all specimens were evaluated according to a scoring system. Results Group 1 specimens always showed normal featur es in the conjunctival epithelium. In group 2, rigid and gas-permeable lenses produced greater changes in conjunctival morphology than soft lenses, especially as regards cellularity, nucleus/ cytoplasm ratio, g oblet cell distribution and total score. On the contrary, in group 3 w earers of soft lenses showed higher partial and total scores than wear ers of gas-permeable and rigid lenses. Conclusions In asymptomatic CL wearers conjunctival morphology was better preserved in wearers of sof t lenses. In patients with intolerance problems, wearers of soft lense s showed the worst cytological features. Impression cytology, evaluate d with this scoring system, can be used to demonstrate epithelial dama ge occurring in CL-wearing patients.