Impression cytology, tear film break up, and Schirmer test in patients with inactive trachoma.

Schirmer I and tear film break up time (BUT) test were used to determine cytological changes and conjunctival surface epithelial morphology was investigated using impression cytology in patients with inactive trachoma; patients with mild and severe scarring, and control subjects, were compared. Schirmer I, BUT, and goblet cell populations were significantly lower whereas the grade of squamous metaplasia was significantly higher in patients with inactive trachoma. There was a close correlation between our findings and the clinical severity of trachoma.