Usefulness of Topical Non-Steroidal Anti-Inflammatory Drugs or Steroids Before Trabeculectomy and Clinical Outcomes

Overview

Antiglaucoma medication have been shown to induce subclinical conjunctival inflammation in a considerable proportion of glaucoma patients. Today, trabeculectomy still remains the gold standard as surgical treatment of medically uncontrolled glaucoma disease. However, this procedure is associated with variable possible complications, of which subconjunctival fibrosis is the most frequent one. The latter results in a non-functional filtering bleb. As a consequence, either additional interventions such as laser suture lysis, needling, bleb revision or additional IOP-lowering medication is necessary. Previous studies demonstrated a benefit of the use of topical steroids postoperatively in reducing inflammation and subsequent subconjunctival fibrosis. In this perspective, we will prospectively explore the usefulness of topical NSAID or corticosteroid therapy preoperatively as compared to placebo in subjects scheduled for first-time trabeculectomy, without interrupting topical antiglaucoma therapy. This will allow us to determine wether the impact of longterm topical antiglaucoma therapy on subclinical conjunctival inflammation which possibly result in postoperative fibrosis and bleb failure can be reversed by anti-inflammatory medication before filtering surgery.

This prospective double-blind randomized placebo-controlled clinical trial was approved by our institutional review board and adheres to the tenets of the Declaration of Helsinki. Patients who agree for the study had to sign an informed consent. Eligible subjects will be subsequently allocated into one of three topical study medication groups by a computer-based randomisation programme: the placebo group received artificial lacrimal tears (Liquifilm®), the NSAID group a non-steroidal anti-inflammatory drug (Aculare®, ketorolac), and the CS group a corticosteroid (FML®, fluorometholone). All study medication is made by the same pharmaceutical manufacturer (Allergan™), and contained the preservative benzalkonium chloride. Each subject of the 3 study groups will have to take one drop of their study medication four times daily for one month before filtering surgery in addition to their routine antiglaucoma medication. The trabeculectomy technique will be done according to a modified Moorfields procedure by experienced surgeons (IS, TZ)using a standard fornix-based approach. Patients will be postoperatively examined on days 1 and 2, at weeks 1, 2, and 4, and at months 3, 6, 12, 18 and 24 following trabeculectomy. IOP will be measured by Goldmann applanation tonometry. IOP outcomes will be the observed IOP values and relative (percentage reduction) IOP reduction as compared to baseline at the different postoperative time points. In addition, complete (without additional postoperative medication) and qualified (with and without additional postoperative medication), and number of postoperative additional treatments (needling, laser suture lysis, needling revision) in the study eye will be assessed. Statistical Analysis Before the onset of the study, sample size and power calculations are performed. In addition, a randomization programme was set up. A multivariate regression model was used to compare the IOP evolution between the three groups .