Evaluating an impression cytology grading system (IC score) in patients with dry eye syndrome

Purpose To evaluate the IC score, a newly developed grading system for the morphological alterations of the ocular surface as a diagnostic tool in relation to type and severity of dry eye disease. Methods Impression cytological specimens of 309 patients with simple dry eye (S-DE), 50 patients with Sjogren's syndrome and dry eye (SS-DE), and 39 patients with connective tissue disease and dry eye (CTD-DE) were examined. In all, 10 different morphological parameters were judged with points (IC subscores) and summarized to the IC score. IC score and subscores were correlated to tear function test results and with each other. Results SS-DE patients had the highest IC scores and IC subscores. IC scores and IC subscores correlated significantly with the fluorescein staining of the cornea in all three patient groups. They were correlated to the rose bengal score in SS-DE and S-DE patients. The analysis of the IC subscores showed that there are significant correlations between most of the morphological alterations investigated. This underlines the importance of each parameter for the summarized IC score. Conclusion The IC score provides detailed information about the morphological alterations of the bulbar conjunctiva. It has proven to be useful for the differentiation of dry eye diseases and might help in the investigation of the pathogenesis of these diseases as well as for follow-up and therapy control.