Baerveldt Plate Area Comparison (BPAC)

Study Overview
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Brief Summary
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This research is being done to compare the safety and effectiveness of two sizes of the Baerveldt glaucoma implant. A Baerveldt glaucoma implant is one of the most common types of glaucoma operations performed. This procedure works by providing a route by which fluid can drain out of the eye to decrease the intraocular pressure. The Baerveldt implant does this by placing a tube into the eye which shunts aqueous fluid to a silicone plate which is attached to the sclera (white portion of the eye). It is this plate that comes in two different sizes (250 square millimeters and 350 square millimeters). Earlier studies have shown that larger plate sizes produce lower eye pressures but that they may also result in more complications. While both Baerveldt devices are currently in use and have been shown to be safe and effective, it is unclear if one is superior to the other. The purpose of this study is to see if one size of device works better with fewer complications.

Official Title
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Baerveldt Plate Area Comparison (BPAC)

Conditions
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Glaucoma

Intervention / Treatment
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* Procedure: Baerveldt Device surgical Procedure


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age over 18 Intra-Ocular Pressure (IOP) > 18 mm Hg and < 40 mm Hg on medical therapy Previous ocular surgery limited to (cataract, corneal transplant, trabeculectomy, vitrectomy) Consent signed Exclusion Criteria: Unwilling or unable to give consent, unwilling to accept randomization, or unable to return for scheduled protocol visits Pregnant or nursing Neuro-Linguistic Programming (NLP) vision Iris neovascularization or proliferative retinopathy Epithelial or fibrous downgrowth Chronic or recurrent uveitis Steroid-induced glaucoma Severe posterior blepharitis Previous cyclodestructive procedure Conjunctival scarring from prior ocular trauma or cicatrizing disease (e.g. Stevens Johnson syndrome, ocular pemphigoid) precluding Baerveldt implantation. Functionally significant cataract Need for Baerveldt implant combined with other ocular procedures (ie cataract surgery,penetrating keratoplasty, or retinal surgery) or anticipated need for additional ocular surgery Prior glaucoma drainage device (tube) implant Prior retinal surgery with remaining silicone oil Prior scleral buckling procedures

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Arm A - Baerveldt 250 mm2<br>Patients receiving Baerveldt 250 mm2 | Procedure: Baerveldt Device surgical Procedure<br>* Implant surgery<br>|
| Experimental: Arm B - Baerveldt 350 mm2<br>Patients receiving Baerveldt 350 mm2 | Procedure: Baerveldt Device surgical Procedure<br>* Implant surgery<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual Acuity as assessed by Early Treatment Diabetic Retinopathy Study (EDTRS) | Visual acuity is an important outcome variable in the BPAC. Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity testing will be employed at the Qualifying Assessment and at every follow-up visit.The patient starts are the top of the chart and begins to read down the chart. The patient reads down the chart until he or she reaches a row where a minimum of three letters on a line cannot be read. The patient is scored by how many letters could be correctly identified. ETDRS visual acuity is required at the Qualifying Assessment and at the 1 year, 3 year, and 5 year follow-up visits | Up to 5 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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glaucoma, Baerveldt Implants