Effects of Punctal Occlusion on Clinical Signs and Symptoms and on Tear Cytokine Levels in Patients with Dry Eye.

PURPOSE:To investigate changes in signs, symptoms, and tear cytokines following punctal plug occlusion in patients with dry eye. METHODS:A single-center study was conducted at Singapore Eye Research Institute. Nonabsorbable punctal plugs were inserted in the lower punctum of both eyes in patients with moderate dry eye. Over 3 weeks, in the more severe eye, dry eye symptoms, fluorescein corneal staining, Schirmer I (without topical anesthesia) test, tear film breakup time (TFBUT), and safety were assessed. Cytokine and matrix metalloproteinase-9 (MMP-9) levels in tear samples were measured. RESULTS:Twenty-nine patients (mean age 49.8 years) with moderate dry eye were evaluated. At baseline, mean (standard deviation) global symptoms score was 53.8 (26.5), Schirmer I test score was 5.1 (2.8) mm, and TFBUT was 2.2 (0.6) seconds. After 3 weeks, punctal occlusion significantly reduced global irritation symptoms score (P<.001) and decreased fluorescein staining in all zones (P<.01) except the inferior zone (P=.42). No significant association between levels of cytokines or MMP-9 and either TFBUT or global irritation symptoms were observed at baseline. Levels of several cytokines and MMP-9 were higher in patients with Schirmer I test scores ≤8 mm at baseline. After 3 weeks of punctal occlusion, no significant changes in overall cytokine or MMP-9 levels were observed. CONCLUSIONS:Punctal plug occlusion provided symptomatic relief and reduced fluorescein staining in all except the inferior zone. However, insertion of punctal plugs had minimal effect on tear cytokines and MMP-9 levels, suggesting a need for earlier treatment with anti-inflammatory agents for management of dry eye disease.