Role of Matrix Metalloproteinase-9 in Diagnosis of Dry Eye

Abstract Background: Dry eye is a “multifactorial disease of the tears and ocular surface that results in symptoms of discomfort, visual disturbance, and tear film instability with potential damage to the ocular surface”. Symptoms of dry eye, which include visual disturbances and pain/dysesthesias, have been found to negatively impact quality of life. Aim of Study: To assess the presence of ocular surface Matrix Metalloproteinase-9 (MMP-9) in dry eye by Infla-mmaDry® test. Patients and Methods: A prospective cross-sectional study included a total of 40 eyes with dryness. This study was involved patients visiting outpatient clinic in Qalawoon Hospital from December 2018 till May 2019. The tear film was analyzed for MMP-9 by InflammaDry®test, symptoms and signs of dry eye disease were evaluated using the Ocular Surface Disease Index (OSDI) questionnaire, Tear Breakup Time (TBUT), corneal staining, Schirmer and Meibomian gland examination. Results: Mean age of the study population was 39.45 years ±9.06 SD (range 30-60), sixty five percent of study population were females. Mean of Ocular Surface Disease Index was 23.05±5.00 SD (14-33 range), Schirmer test mean was 4.60mm/5 minutes ±  2.11 SD (1-8mm/5min range), Tear Breakup Time mean was 5.40 seconds ±1.61 SD (3-9 range) and corneal staining mean was 2.45±0.68 SD (2-4 range). Seventy five percent of the study population had Meibomian glad dysfunction. There was a highly statistically significant correlation between InflammaDry® results and Meibomian glands dysfunction. There were statistically non-significant correlations between Ocular surface disease index, Schirmer test results, tear breakup time, corneal staining and positive results of InflammaDry®test. Conclusion: There is direct correlation between inflam-mation and dry eye disease. Also, Matrix metalloproteinase testing in dry eye disease is a valuable new diagnostic tool to identify the presence of ocular surface inflammation.