Overview

The goal of this randomized controlled clinical trial is to learn whether two minimally invasive bleb-forming glaucoma implants can effectively treat adult patients with open-angle glaucoma who require surgical lowering of intraocular pressure (IOP). Specifically, the study evaluates whether the PRESERFLO™ MicroShunt is at least as effective as the XEN®-63 Gel Stent in reducing IOP after surgery. 

The main questions it aims to answer are:

• Does the PRESERFLO™ MicroShunt provide IOP reduction at 12 months that is non-inferior to the XEN®-63 Gel Stent?
• How do the two devices compare over 24 months with respect to medication reduction, need for additional glaucoma procedures, complications, and preservation of visual function and ocular structures?

Participants will:

• Be randomly assigned (1:1) to receive either the XEN®-63 Gel Stent or the PRESERFLO™ MicroShunt during a single glaucoma surgery.
• Attend scheduled follow-up visits over 24 months for eye-pressure measurements, vision testing, visual-field testing, OCT imaging, endothelial-cell counts, and safety assessments.
• Receive standard postoperative care and report any complications or additional treatments during the study period.

Eligibility

Inclusion Criteria:

• \>40 years of age
• An established diagnosis of: Primary open angle glaucoma, Normal tension glaucoma, Pigment dispersion glaucoma (PDG) or Pseudoexfoliative glaucoma (PEX)
• Inadequately controlled on maximum tolerated medical therapy.
• Mean Deviation (MD) \</= -3
• Intraocular pressure of 14-28 mmHg
• Endothelial Cell Count ≥1000 cells/mm2

Exclusion Criteria:

• An established diagnosis of: Closed-angle glaucoma or Secondary open-angle glaucoma (besides PDG and PEX)
• Lens status: Aphakic patients or Anterior chamber intraocular lens
• Previous procedures: Glaucoma shunt/valve/ surgery or cyclodestructive procedure, Selective laser trabeculoplasty within the past 3 months, Incisional ophthalmic surgery involving the conjunctiva within the past 3 months, Clear corneal cataract or trabecular meshwork surgery conducted within the past 6 months.
• Presence of intraocular silicone oil
• No light perception vision
• Current corticosteroid use (ocular or oral)
• Conjunctival pathologies (e.g., pterygium)
• Active inflammation (e.g., blepharitis, conjunctivitis, keratitis, uveitis)
• Vitreous present in the anterior chamber
• Active iris neovascularization or neovascularization of the iris within 6 months of the surgical date
• Unwillingness or inability to give consent, accept randomization or return for and participate in scheduled protocol visits