Baerveldt 350 vs Ahmed ClearPath 250 for the Treatment of Glaucoma

Study Overview
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Brief Summary
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To compare the safety and efficacy of Baerveldt 350 and Ahmed ClearPath 250 tube shunts in lowering IOP in glaucoma patients.

Detailed Description
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Tube shunt implantation is a common type of surgery considered standard of care for treating significant potentially-blinding glaucoma where medical and laser treatment, and previous surgeries, have failed to control intra-ocular pressure (IOP) sufficiently to stop glaucoma progression towards blindness. Since a larger plate tube (e.g., Baerveldt 350) is more difficult to implant requiring longer surgical time and intraoperative ocular muscle manipulation with possible patient discomfort, a smaller plate tube shunt (e.g., Ahmed ClearPath 250) requiring shorter surgical time and no ocular muscle manipulation may have an advantage if the long term surgical outcomes were the same. However, the literature is lacking regarding the effect of the tube plate size on the final outcomes of tube shunt implantation. Most published comparisons are between totally different types of tube shunts regardless of plate size, often made of different materials, often comparing valved vs. non-valved tube shunts,combining different plate sizes in the same study groups,5 mixing tubes with or without combined cataract surgery in the same study groups, or comparing surgeries performed by several surgeons utilizing different surgical methods. Further, all these studies utilize tubes implanted into the anterior chamber (AC) thus increasing the risk of corneal failure, with no comparisons at all between tube shunts implanted through the ciliary sulcus of the eye designed to reduce the risk of corneal failure. Our Principle Investigator (AW) is specializing and well-published in this type of tube shunt implantation. This prospective randomized trial is designed to resolve all these confusing factors in the literature and finally provide the answer of whether tube plate size has an effect on the final outcomes of tube shunt implantation by performing a clean study that would isolate the effect of tube plate size on long term outcomes. To achieve this goal our study will utilize two non-valved tube shunts with a different plate size (350 vs. 250 mm2) made of identical materials, in eyes that have already had cataract surgery, and all performed by the same surgeon (AW) through the ciliary sulcus.

Official Title
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Outcomes Comparison Between Baerveldt 350 and Ahmed ClearPath 250 Tube Shunts for the Treatment of Glaucoma

Conditions
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Glaucoma

Intervention / Treatment
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* Device: Baerveldt 350 vs. Ahmed ClearPath 250 tube shunt implantation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Significant uncontrolled glaucoma despite medical, laser or previous surgical therapy that requires tube shunt implantation as standard-of-care to stabilize the glaucoma and preserve vision. Pseudophakia Patients who are willing to participate and are able to understand and sign the study consent form. Age ≥18 years. Exclusion Criteria: Phakic eyes (no previous cataract surgery). Aphakic eyes (status post previous cataract removal but without a lens implant). Age <18 years. Women of child-bearing age. Patients unable to comprehend and sign the study consent form. Women who are pregnant.

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
Interventional Model Description: Comparison between 2 groups of patients requiring tube shunt implantation to treat their severe uncontrolled glaucoma. One group will receive a unilateral Baerveldt 350 tube shunt and the other a unilateral Ahmed ClearPath 250 tube shunt. The patients will be sequentially randomized into one of these tube shunts.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Baerveldt 350<br>The patients in this arm will receive a Baerveldt 350 tube shunt implantation for the treatment of their severe uncontrolled glaucoma. | Device: Baerveldt 350 vs. Ahmed ClearPath 250 tube shunt implantation<br>* Baerveldt 350 vs. Ahmed ClearPath 250 tube shunt implantation for the treatment of severe uncontrolled glaucoma.<br>|
| Active Comparator: Ahmed ClearPath 250<br>The patients in this arm will receive an Ahmed ClearPath 250 tube shunt implantation for the treatment of their severe uncontrolled glaucoma. | Device: Baerveldt 350 vs. Ahmed ClearPath 250 tube shunt implantation<br>* Baerveldt 350 vs. Ahmed ClearPath 250 tube shunt implantation for the treatment of severe uncontrolled glaucoma.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in intraocular pressure | Change in Intraocular pressure between preoperative baseline and postoperative follow-up visits | 2 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Glaucoma, Baerveldt 350, Ahmed ClearPath 250