Tear Film Stability in Sjögren Syndrome Patients Treated with Hyaluronic Acid Versus Crosslinked Hyaluronic Acid-Based Eye Drops

Purpose: To compare the stability of the tear film after instillation of eye drops containing hyaluronic acid (HA) or crosslinked hyaluronic acid (CLHA)-based in patients with Sjögren syndrome-related dry eye (SSDE). Methods: Forty subjects were included in this study and were divided into 2 groups: The first group (control group) consisted of 20 healthy volunteers; the second group (study group) constituted of 20 suffering from SSDE; before and 5, 30, and 60 min after instillation of eye drops the surface regularity index (SRI) and surface asymmetry index (SAI) were registered. Results: Comparing HA and CLHA, in the control group, SAI show statistically significant difference in the time 0 and in time 5, whereas there is no a statistically significant difference after 30 and 60 min from instillation. For SRI there is no statistically significant difference at any time. In SSDE group there is no statistically significant difference in the time 0 and 5, whereas there is a statistically significant difference after 60 min for SAI, and after 30 and 60 min for SRI from instillation. Both SRI and SAI in dry eyes were significantly greater than in control eyes (P < 0.05). Conclusion: Our study showed a better efficacy of CLHA compared with HA in maintaining the stability of the tear film in a patient suffering from SSDE.