Steroids and/ or Non-steroidal Anti-inflammatory Drugs in the Postoperative Regime After Trabeculectomy. An Investigator-initiated Randomized Study (The SNAP Study)

PURPOSE:

Glaucoma is the leading cause of non-curable blindness globally. Patients with glaucoma will get a gradual narrowing of the visual fields caused by compression at the optic nerve head due to increased intraocular pressure. Thus the main preventive strategy is to reduce intraocular pressure, initially by eye drops and/or laser treatment but in some patients surgery is warranted. The surgical procedure (trabeculectomy) most widely performed worldwide creates a path from the anterior chamber to the subconjunctival space and thereby lowers the IOP by producing a more efficient drainage of the aqueous humour. Surgical success depends upon controlling post-operative inflammation to ensure a functional drainage. The purpose of this blinded, randomized study is to investigate which anti-inflammatory treatment provides better long-term control of intra-ocular pressure (IOP) following glaucoma surgery (trabeculectomy) by comparing topical NSAIDs to topical steroids. Additionally, we want to explore the mechanisms behind the pathophysiology of glaucoma by evaluating retinal and optic nerve head perfusion before and after IOP lowering surgery. The primary outcome is the intraocular pressure 12 months after surgery measured by applanation tonometry.

MAIN HYPOTHESIS:

• NSAIDs and steroids are equally effective in assuring long-term filtering function and controlling IOP after trabeculectomy but may be associated with different risk profiles and bleb morphology
• Patients with lower post-operative IOP demonstrate less progression of visual field loss
• Trabeculectomy lowers IOP and provides better microcirculation in and oxygenation of inner retinal layers (i.e. ganglion cell layer) and the optic nerve head