Safety Study of Aqueous Suppression After Ahmed Glaucoma Valve (AGV) Implantation
The AGV implant is designed to open when the IOP is between 8 mmHg and 10 mmHg, and thus maintains an IOP of 8 mmHg or higher. In the early period after glaucoma drainage device (GDD) surgery the intraocular pressure (IOP) classically goes through 2 phases. The hypotensive phase occurs immediately after surgery, lasts around 1 week. This is followed by the hypertensive period where the IOP tends to rise steadily above 21mmhg.
The hypertensive response seems to occur more commonly after Ahmed GDD surgery than nonvalved implants, It was reported to occur in 40% to 80% of cases. Although the hypertensive phase can last as long as 6 months it is usually during the first 1 to 4 weeks, when there is intense congestion of the bleb wall, that IOP is highest.
Previous study showed that when aqueous comes into contact with conjunctiva and Tenon's capsule,an inflammatory reaction occurs.Factors such as prostaglandins, eicosanoids, tissue growth factor beta (TGF β)has been shown to occur in glaucomatous aqueous. These mediators induce an inflammatory reaction, and if excessive, will result in fibrosis and poor functioning of the bleb. High pressure within the bleb also results in the secretion of TGF β by the bleb lining. It may result in inflammation of the bleb wall and subsequent fibrosis and poor bleb function. The investigators supposed that with early use of aqueous suppressant medication after AGV implantation, the concentration of inflammatory mediators decreased in subconjunctival space and may lead to better IOP control after shunt surgery.
|Study Design:||Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Investigator)
Primary Purpose: Treatment
|Official Title:||Early Intra Ocular- Pressure Control Using Aqueous Suppressive Agents After Ahmed Glaucoma Valve Implantation|
- intraocular pressure-hypertensive phase success rate [ Time Frame: during first 3 months ] [ Designated as safety issue: Yes ]during first 3 months
- intraocular pressure success rate [ Time Frame: after 12 months ] [ Designated as safety issue: Yes ]after 12 months
|Study Start Date:||January 2011|
|Estimated Primary Completion Date:||March 2013 (Final data collection date for primary outcome measure)|
Active Comparator: Timolol-trusopt
Dosage:One drop/12hours,duration:3 months
Other Name: cosopt
Placebo Comparator: placebo,Artificial tear
dosage:one drop/12 hours,duration:3 months
|Contact: Mohammad pakravan, Associate Professoremail@example.com|
|Iran, Islamic Republic of|
|Labbafinejad medical center||Recruiting|
|Tehran, Iran, Islamic Republic of|
|Contact: Mohammad Pakravan, Associate Professor firstname.lastname@example.org|
|Principal Investigator: Mohammad Pakravan, Associate Professor|