Dry eye and inflammation of the ocular surface after cataract surgery: effectiveness of a tear film substitute based on trehalose/hyaluronic acid vs hyaluronic acid to resolve signs and symptoms

PURPOSE: To compare the effect of trehalose 3%/hyaluronic acid 0.15% vs hyaluronic acid 0.15% eyedrops in reducing ocular surface inflammation after cataract surgery. SETTING: Perugia, Italy. DESIGN: Randomized, prospective study. METHODS: Patients with healthy ocular surface were enrolled. Tear break-up time (TBUT), Schirmer test, corneal fluorescein staining (CFS), ocular surface disease index (OSDI) and in vivo confocal microscopy (IVCM) were performed preoperatively and at 1 months, 4 months, and 8 months postoperatively. Patients were randomly assigned to receive trehalose 3%/hyaluronic acid 0.15% eyedrops (Group A), hyaluronic acid 0.15% eyedrops (Group B), or no treatment (Group C). RESULTS: 98 patients were randomized as follows: 33 in Group A, 33 in Group B, and 32 in Group C. Schirmer test increased at 1-month follow-up in Group A and unchanged in Groups B and C. TBUT and CFS increased at 1-month follow-up in Group A and after 8 months in Groups B and C. OSDI score decreased at 1-month follow-up in Group A and at in Groups B and C. IVCM showed a reduction in the number of nerve fibers of the subbasal nerve plexus at 1 month in all groups and progressively increased to preoperative levels at 4 months in Group A, and at 8 months in Groups B and C. Tortuosity and reflectivity of subbasal plexus progressively decreased to became significant at 4-month follow-up in Group A whereas increased at 1-month follow-up and become normal at 8-month follow-up in Groups B and C. Langerhans cells and activated stromal keratocytes were higher in Groups B and C throughout the follow-up with a significantly lower density of hyperreflective stromal cells in Group A. CONCLUSIONS: Trehalose 3%/hyaluronic acid 0.15% eyedrops were effective in reducing inflammation and dry-eye symptoms.