Clinical Usefulness of Conjunctival Brush Cytology in the Diagnosis of Dry Eye Syndrome

ABSTRACT

PURPOSE: To investigate the clinical usefulness of conjunctival brush cytology (CBC) in the diagnosis of dry eye syndrome. METHODS: Conjunctival impression cytology (CIC) was performed on the right eye and CBC was performed on the left eye in 24 patients with dry eye syndrome (9 patients with Sjogren's syndrome (SS) and 15 patients with non-Sjogren syndrome (Non-SS)) and 7 control subjects. The grade of squamous metaplasia was analyzed and the correlation between the grade and tear surface parameters was evaluated. RESULTS: The squamous metaplasia grade score in CIC and CBC were 2.44+/-0.73 and 1.56+/-1.01 in SS patients (p=0.047), 1.53+/-0.74 and 0.80+/-0.78 in Non-SS patients (p=0.017), and 0.43+/-0.54 and 0.14+/-0.38 (p=0.250) in control subjects, respectively. In SS patients, the score correlated significantly with the symptom score, basal tear secretion, break-up time (BUT) and keratoepitheliopathy score in CBC (p<0.05), but did not correlate with the tear surface parameters in CIC. In Non-SS patients, the score correlated significantly with the symptom score, basal tear secretion, BUT and keratoepitheliopathy score in CBC, and with the keratoepitheliopathy score in CIC (p<0.05). CONCLUSIONS: CBC is a more useful method than CIC in the diagnosis of dry eye syndrome.