Effect of Prophylactic Aqueous Suppression on Hyperencapsulation of Ahmed Glaucoma Valves
|First Received Date ICMJE||February 13, 2012|
|Last Updated Date||February 15, 2012|
|Start Date ICMJE||February 2012|
|Primary Completion Date||Not Provided|
|Current Primary Outcome Measures ICMJE
||Intraocular pressure [ Time Frame: 4 months postoperative ] [ Designated as safety issue: No ]
The primary outcome measure is intraocular pressure (IOP) at 4 months postoperative. This will be a washout IOP (i.e. all glaucoma eye drops will be stopped at 3 months postoperative in all study patients)
|Original Primary Outcome Measures ICMJE||Same as current|
|Change History||Complete list of historical versions of study NCT01535768 on ClinicalTrials.gov Archive Site|
|Current Secondary Outcome Measures ICMJE
|Original Secondary Outcome Measures ICMJE||Same as current|
|Current Other Outcome Measures ICMJE||Not Provided|
|Original Other Outcome Measures ICMJE||Not Provided|
|Brief Title ICMJE||Effect of Prophylactic Aqueous Suppression on Hyperencapsulation of Ahmed Glaucoma Valves|
|Official Title ICMJE||Effect of Prophylactic Aqueous Suppression on Hyperencapsulation of Ahmed Glaucoma Valves|
After implantation of an Ahmed glaucoma valve in patients with glaucoma, hyperencapsulation phase is an unwanted postoperative phenomenon, typically occurring with the free 3 months postoperatively. When this does occur, it is treated with aqueous suppressant eye drops.
This study aims to determine if it is possible to reduce the rate of hyperencapsulation phase. Patients in the treatment group will receive aqueous suppressant eye drops before the hyperencapsulation phase starts. Treatment will be initiated once their intraocular pressure is above a pre-defined level, and will target a pre-defined range.
Patients with glaucoma requiring tube shunt surgery, with or without simultaneous cataract surgery, will be enrolled in this prospective randomized controlled study at ten sites across Canada and the United States (to be determined). Patients with highly advanced glaucoma at high risk of fixation loss, neovascular glaucoma, chronic uveitis, marked corneal disease, sulfa allergy, renal disease or any contraindication to diamox use will be excluded.
Patients scheduled for Ahmed glaucoma valve surgery, with or without cataract surgery, will be randomized using a stratified central block randomization approach to the treatment group or control group. Those scheduled for combined cataract and tube shunt will be randomized separately from those receiving tube shunt alone. Surgeons will be masked to the postoperative treatment or control group at the time of surgery since randomization will occur when the patient is one-week postoperative Those in the treatment group would receive short-term prophylactic aqueous suppression for the first 3 postoperative months to maintain intraocular pressure (IOP) between 7 and 10mmHg. The control group would not receive prophylactic aqueous suppression, but would be treated using a similar protocol as the treatment group in the event that an Hyperencapsulation phase (HEP) endpoint is met.
Prophylactic aqueous suppression in the study group would only be given for the 1st 3 months postoperatively. At the 3 month visit, aqueous suppression will be stopped. The primary outcome measure is washout IOP at 4 months postoperative. Washout IOP will be checked one month after discontinuation (earlier if needed i.e., advanced glaucoma patients).
Beyond 3 months, aqueous suppressants would be used at the clinician's discretion based on IOP.
At the conclusion of the study, the 4-month postoperative washout IOP, the incidence of HEP, the 12-month IOP, the 13-month washout IOP, and medication requirement would be compared between the treatment and control arms.
|Study Type ICMJE||Interventional|
|Study Phase||Phase 4|
|Study Design ICMJE||Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Single Blind (Outcomes Assessor)
Primary Purpose: Treatment
|Intervention ICMJE||Drug: Aqueous Suppressant Eye Drops
Aqueous suppressant eye drops added stepwise to achieve IOP between 7-10mmHg. First, a beta blocker eye drop (timolol 0.25% 1 gtts in study eye BID OR timolol 0.5% 1 gtts in study eye BID).
Next, a topical carbonic anhydrase inhibitor eye drop. (brinzolamide 1% 1 gtts in study eye TID OR dorzolamide 2% 1 gtts in study eye TID) Next, a topical alpha agonist eye drop. (brimonidine 0.1% 1 gtts in study eye TID OR brimonidine 0.15% 1 gtts in study eye TID).
Next, a topical prostaglandin analogue eye drop. (latanoprost 0.005% 1 gtts in study eye qhs OR travoprost 0.004% 1 gtts in study eye qhs OR bimatoprost 0.01% 1 gtts in study eye qhs OR bimatoprost 0.03% 1 gtts in study eye qhs) Finally, stop the topical carbonic anhydrase inhibitor eye drop and start oral acetazolamide. (acetazolamide 250mg PO OD)
|Study Arm (s)||
|Publications *||Not Provided|
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
|Recruitment Status ICMJE||Recruiting|
|Estimated Enrollment ICMJE||150|
|Completion Date||Not Provided|
|Primary Completion Date||Not Provided|
|Eligibility Criteria ICMJE||
|Ages||18 Years and older|
|Accepts Healthy Volunteers||No|
|Location Countries ICMJE||Canada|
|NCT Number ICMJE||NCT01535768|
|Other Study ID Numbers ICMJE||PASAGV2012|
|Has Data Monitoring Committee||Yes|
|Responsible Party||Amandeep Rai, Credit Valley EyeCare|
|Study Sponsor ICMJE||Credit Valley EyeCare|
|Collaborators ICMJE||Canadian Glaucoma Clinical Research Council|
|Information Provided By||Credit Valley EyeCare|
|Verification Date||February 2012|
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