A Preservative-Free Approach – Effects on Dry Eye Signs and Symptoms After Cataract Surgery

Abstract

Purpose

To compare the effect of treatment with preservative-free dexamethasone, NSAIDs and trehalose/hyaluronic acid eye drops with the preservative benzalkonium chloride containing dexamethasone and NSAIDs after cataract surgery in dry versus non-dry eyes.

Patients and Methods

In this prospective randomized intervention study, dry eye tests were performed before and 6 weeks after cataract surgery. Patients were considered as having dry eye, SDE (sign of dry eye), if at least one of the following dry eye tests were abnormal; corneal fluorescein staining (CFS), non-invasive keratograph breakup time (NIKBUT) or tear osmolarity. Patients with SDE were randomly assigned to one of two groups. Group 1 patients were treated with dexamethasone and bromfenac eye drops with the preservative benzalkonium chloride (BAC). Group 2 patients were treated with preservative-free dexamethasone and preservative-free diclofenac, as well as a preservative-free lubricant with trehalose and hyaluronic acid both before and after surgery. Patients with normal tear film status acted as the control group (group 3) and received same treatment as group 1.

Results

A total of 215 patients were enrolled six weeks after surgery, the number of patients with SDE decreased significantly in groups 1 and 2 (p <0.001). Subjective symptoms and objective measures including osmolarity, NIKBUT, CFS, and tear film thickness (TFT) improved after surgery, tear production remained unchanged, while corneal sensitivity and meibomian gland dysfunction (MGD) parameters worsened. In the control group with normal tear-film status, SDE increased significantly after the surgery (p <0.001). There were no statistically significant differences in tear film parameters between the three groups after surgery.

Conclusion

After cataract surgery, patients with mild to moderate dry eyes may experience improved tear film status and reduced symptoms. However, we found no additional beneficial effect on dry eye parameters with treatment with preservative-free dexamethasone, NSAIDs, and lubricants compared to preservative-containing eye drops.

Keywords:

• sign of dry eye
• cataract surgery
• osmolarity
• corneal fluorescein staining
• non-invasive keratograph tear break-up time
• ocular surface disease index
• meibomian gland dysfunction

Data Sharing Statement

The original data and anonymous patient files are stored on a secured server (Tjenester for Sensitive Data, TSD) at the University of Oslo for 10 years. Supplemental information can be available from the Corresponding Author upon reasonable request.

Research Ethics and Consent

The study followed the tenets of the Declaration of Helsinki, adhered to good clinical practice, and was approved by the Regional Committee for Medical and Health Research Ethics in Norway (Ref. 2020/64847). The project protocol was registered in Clinicaltrials.gov: NCT 05433428 (first submitted 10.08.2023, first posted 27.06.2022). Written informed consent was obtained from all participants at their first visit.

Disclosure

Richard (Rick) Potvin reports consulting fees from Alcon and Hoya. Dr Tor Utheim reports being one of around 20 owners of the Norwegian Dry Eye Clinic, during the conduct of the study. The authors report no other conflicts of interest in this work.

Additional information

Funding

The study was supported by The Research Council of Norway (project nr. 306649).