AIM: To investigate the value of conjunctival impression cytology(CIC)in the diagnosis of allergic conjunctivitis(AC).

METHODS: A case-control study. Forty patients(80 eyes)who were clinically diagnosed with AC in our department from January to February 2021 were included in the study,and 40 normal controls(80 eyes)were enrolled too. All subjects underwent double upper palpebral CIC examinations. Observed the morphology and number of conjunctival eosinophils and carried out Tseng classification in each group. To Compare the differences between the results of the two groups and analyze the effects of gender, age and course of disease on the results of CIC eosinophil examination in AC group.

RESULTS: The positive rate of eosinophils in the upper palpebral CIC examination of AC patients was significantly higher than that of the normal control group(χ²=57.744, P<0.001); The Tseng grade of AC patients was also higher than that of the normal control group(Z=-2.453, P<0.05). Gender, age and course of disease had no significant effect on the results of CIC eosinophils in AC group(all P >0.05).

CONCLUSION: CIC examination is simple, and the result is objective and accurate. It has good application value in the diagnosis of AC.