Ocular surface changes in keratoconjunctivitis sicca with silicone punctum plug occlusion

Abstract

Purpose: To evaluate histopathologic and clinical response to silicone plug insertion in dry eye patients.

Methods: Punctal plugs were placed in 32 eyes of 18 dry eye patients with aqueous deficiency who were on maximum medical therapy and who had Schirmer testing with topical anesthetic measuring less than 5 mm. Pre-treatment and post-treatment (6 weeks and 1 year) evaluations included temporal and inferior quadrant impression cytology examinations, Schirmer-1, BUT, corneal fluorescein and rose-bengal staining patterns and questionnaire scores. The cytology samples were graded according to the method described by Nelson.

Results: There was an improvement in subjective symptoms of patients 6 weeks after punctal occlusion. Corneal fluorescein and rose-bengal staining scores decreased from a mean of 5.33 +/- 1.74 to 1.37 +/- 1.48 and from 5.90 +/- 1.2 to 2.45 +/- 1.89 (p < 0.05) respectively. BUT values increased from 2.98 +/- 1.1 to 11.3 +/- 3.1 seconds (p < 0.05) at 6 weeks post-treatment. Increase in goblet cell density was observed after punctal occlusion at 6 weeks (p < 0.05) and at 1 year (p < 0.05) compared to the pre-treatment values. After occlusion, 3% of temporal specimens had Grade 0 squamous metaplasia, 63% had Grade 1, 34% had Grade 2; while 25% of inferior specimens had Grade 0, 56% had Grade 1, 19% had Grade 2 squamous metaplasia.

Conclusions: Punctum plug occlusion in keratoconjunctivitis sicca provides improvement of tear film stability, ocular surface staining scores, conjunctival squamous metaplasia grades and goblet cell density. Increased ocular surface exposure to essential tear components with punctal occlusion may be important for the genesis of these changes.