Clinical profiles of non dry eye patients and correlations with tear protein levels

An accurate clinical description of the normal patient must be established before the dry eye patient can be accurately profiled. The current study was designed to (a) determine normal values for, and to seek correlations between, clinical tests used for the evaluation of non dry eye patients' tear film and ocular surface, and (b) compare clinical findings with previously reported levels of non-stimulated and stimulated tear proteins for the same group. Thirty non-contact lens wearing patients (age range 20-64 years) were determined to be free of dry eye based on the results of a series of clinical tests. McMonnie's dry eye questionnaire was used as an initial screening step. Clinical tests included lacrimation kinetics (using sealed, calibrated filter paper strips), non-invasive tear break-up time (NIBUT) measurement by Xeroscope, biomicroscopic evaluation of the anterior segment, assessment of tear prism height and regularity, and fluorescein and Rose Bengal staining. No significant correlations were found between age, questionnaire score, lacrimation kinetics final tear secretion rate or NIBUT. However, NIBUT results did vary by gender. Mean NIBUT for females was 46.3 +/- 16.6 (standard deviation) seconds and for males 59.3 +/- 2.1 seconds. some significant correlations were found between clinical test results and levels of non-stimulated and stimulated tear proteins. Overall, the results indicate that this battery of clinical tests will be appropriate for distinguishing between normal and dry eye patients. Combined with tear protein assay, this clinical approach may improve our current understanding of the different types of dry eye.