[Application of impression cytology in diagnosis of ocular surface diseases]

OBJECTIVE: To evaluate the usefulness of impression cytology in diagnosing of ocular surface diseases. METHODS: Impression cytology was performed on 18 eyes with Sjgren's syndrome (dacryosialo-adenopathia atrophicans), 23 eyes with non-Sjgren's syndrome, 15 eyes after thermal or chemical burn at the scarred stage and 20 normal eyes. Conjunctival goblet cell density, conjunctival epithelial squamous metaplasia and corneal cytological features were evaluated respectively. RESULTS: In impression cytology, eyes of Sjgren's syndrome demonstrated a significantly higher grade of squamous metaplasia and lower goblet cell density (P<0.05) as compared with normal eyes and with eyes of non-Sj gren's syndrome in the bulbar conjunctiva, whereas no statistically significant difference of squamous metaplasia grade or goblet cell density was found in the palpebral conjunctiva (P>0.05) in these two groups. In thermal or chemical burned eyes at the scarred stage, the inferior, nasal and temporal bulbar conjunctiva showed higher conjunctival goblet cell density than in the normal eyes (P<0.01). Before surgery of ocular surface reconstruction, conjunctival goblet cells were detected on the corneal area in the 8 thermal or chemical burned eyes. However, the goblet cells in the corneal area of 7 burned eyes were completely resolved after successful ocular surface reconstruction. CONCLUSION The demonstrations of impression cytology in Sjgren's syndrome, thermal or chemical burn are distinctive. Impression cytology is a noninvasive,quick,easy and inexpensive technique, being a useful tool for diagnosis of ocular surface diseases.