Abstract
Purpose To describe the conjunctival impression cytology changes in keratoconus patients with eye rubbing, dry eye and ocular allergy.Methods Descriptive, cross-sectional study. Forty-four eyes of 22 patients with keratoconus, ocular allergy, eye rubbing and dry eye were included. Ocular Surface Disease Index (OSDI) and Ocular Allergy Index (OAI) questionnaires were given to all participants and impression cytology was performed to obtain Nelson’s classification.Results Stage II-IV keratoconus patients had higher grades of squamous metaplasia (p < 0.01979). Eye rubbing with the index and middle finger was related to Nelson grade 3 (p < 0.0032), stage IV keratoconus (p < 0.0007), and a severe OSDI result (p < 0.0035). A severe result in the OAI was associated with stage IV keratoconus (p < 0.0035) and eye rubbing with the knuckles (p < 0.000024).Conclusion Keratoconus is a multifactorial disease where eye rubbing plays an important role in disease progression. Persistent eye rubbing may increase the levels and activity of inflammatory mediators, leading to the development of the disease. Our study suggests that eye rubbing with the knuckles, the index and middle finger can lead to advanced stages of keratoconus. Keratoconus stage IV was associated with a severe OSDI result, and higher degrees of squamous metaplasia (Nelson grade 3).