Conjunctival Impression Cytology and Tear Function in Patients with Keratoconus

OBJECTIVES: The aim of this study was to evaluate the ocular surface alterations of conjunctival cytological changes and tear function in patients with keratoconus. METHODS: A total of 98 eyes with keratoconus and 68 eyes of age- and sex- matched healthy subjects were included in this prospective study. Ophthalmological evaluations, including Ocular Surface Disease Index (OSDI), tear break-up time (TBUT), ocular surface staining (OSS), Schirmer test, and conjunctival impression cytology (CIC), were performed. RESULTS: The mean participant age was 23.4±5.3 years in the keratoconus group and 24.9±6.0 years in the control group. In the keratoconus group, the mean OSDI and OSS scores were statistically significantly higher than those of the controls, and the Schirmer and TBUT results were statistically significantly lower (all p<0.001). The severity of keratoconus was positively correlated with the CIC grade (r=0.292; p=0.004). CONCLUSION: Keratoconus results in deterioration of the ocular surface, including CIC and tear function parameters. The grade of keratoconus appears to be associated with conjunctival cytologic changes.