Trehalose in Hyaluronic Acid Eye Drops May Benefit Dry Eye After Cataract Surgery

For patients undergoing cataract surgery, adding 3% trehalose to 0.15% hyaluronic acid eye drops may effectively help reduce inflammation and signs and symptoms of dry eye, according to research published in the Journal of Cataract & Refractive Surgery.

Fixed trehalose and hyaluronic acid have been of therapeutic interest for tear substitutes in patients with postoperative dry eye; however, the efficacy of combining these 2 molecules for the reduction of signs and symptoms of dry eye and corneal inflammation has not been well studied in patients who have undergone cataract surgery. 

A team of investigators in Italy conducted a prospective, randomized, open-label, comparative analysis in patients undergoing unilateral cataract surgery and intraocular lens implantation to determine whether the addition of trehalose to hyaluronic acid-containing drops would improve patient outcomes.

A total of 98 patients were randomly assigned (1:1:1) to either receive trehalose 3%/hyaluronic acid 0.15% eye drops twice daily for 60 days (group A; n=33), unpreserved hyaluronic acid 0.15% eye drops twice daily for 60 days (group B; n=33), or no tear substitutions (group C; n=32). The ocular surface disease index (OSDI) and confocal microscopy (IVCM) were performed prior to surgery and at 1, 4, and 8 months after surgery. 

At 1 month follow-up, there was a significant increase in Schirmer test from baseline among group A participants (P <.05), but no significant changes were observed in groups B or C. Similarly, tear break-up time significantly increased at month 1 compared to baseline in group A but not significantly in groups B and C. 

The OSDI scores significantly decreased at month 1 in group A, and at month 4 in groups B and C. Corneal epithelial cell density reached baseline levels at month 4 for group A and was significantly higher than baseline levels by month 8. No significant changes were observed in group B and corneal epithelial cell density reached baseline levels at month 4 in patients in group C; however, this increase was not statistically significant.

When assessing the subbasal nerve plexus and the number of subbasal nerve fibers compared with basal nerve fibers, group A had a progressive reduction in the tortuosity of the nerve fibers of the subbasal plexus, which was significantly different from basal values from month 4 of follow-up. These values were significantly lower than group B or C, with similar results for the reflectivity of subbasal nerve fibers. 

Finally, groups B and C had more Langerhan cells and activated stromal keratocytes throughout the follow-up period and significantly lower density of hyperreflective stromal cells as compared with group A. 

“Overall, these results show that cataract surgery induces widespread and persistent inflammation of the corneal-conjunctival surface, leading to dry eye associated signs and symptoms,” according to the research. “These study results suggest that 3% trehalose/0.15% HA could be regarded as a useful tool in postoperative therapeutic management following cataract surgery.”

Reference 

Cagini C, Di Lascio G, Giovanni T, et al. Dry-eye and inflammation of the ocular surface after cataract surgery: study on the effectiveness of a tear substitute based on trehalose/hyaluronic acid versus hyaluronic acid in the resolution of signs and symptoms. J Cataract Refract Surg. Published online March 18, 2021. doi:10.1097/j.jcrs.0000000000000652