Paradoxical Effect of Artificial Tear Drop Use on Signs and Symptoms of Dry-Eye Disease
Narrative Responses:
Purpose
To evaluate the efficacy of mere use of artificial tears in changing the signs and symptoms of dry eye disease (DED), and to compare the effects in patients with mild/moderate vs. more severe disease.
Methods
A total of 30 patients with DED were studied prospectively. Subjects were started on carboxymethyl cellulose artificial tear drops three times a day in addition to their current DED treatment regimen. All ocular immune modulatory medications including topical corticosteroids and cyclosporine were stopped two weeks prior to starting the study. Patients were followed for 12 weeks. In each visit (baseline, weeks 2, 6, 12), DED symptoms were assessed using the Ocular Surface Disease Index (OSDI) questionnaire. Corneal fluorescein staining (CFS), tear break up time (TBUT) and Schirmer’s tests were done at each visit.
Results
Corneal fluorescein staining improved significantly over the course of treatment (p=0.023). For subgroup analysis, DED severity in subjects was categorized to mild/moderate and severe disease according to CFS (19 patients with CFS<=2 [mild/moderate] vs. 11 patients with CFS>2 [severe]). Improvement in CFS maintained significance only in patients with severe DED (p=0.022 in severe vs. p=0.392 in mild/moderate DED). OSDI score did not change significantly (p=0.107) in patients over 12 weeks. Interestingly, OSDI revealed a rising trend in patients with severe DED (p=0.09), suggestive of some exacerbation in patient discomfort. Significant improvement in Schirmer’s (p=0.913) or TBUT (p=0.209) was not appreciable.
Conclusion
Artificial tear drop use significantly improves corneal epitheliopathy (as measured by CFS) in patients with DED, particularly in those with severe disease. However, a modest improvement of staining in severe DED may be associated with paradoxical worsening of symptoms, which we speculate may be due to corneal nerve regeneration.