The goal of this clinical trial is to evaluate the efficacy and safety of Ahmed glaucoma valve (AGV) implantation in the posterior chamber (ciliary sulcus) compared with the traditional anterior chamber placement in patients with refractory pseudophakic glaucoma, who are adults (\>18 years), have undergone cataract surgery with intraocular lens implantation, and are unresponsive to maximal medical therapy.
The main questions it aims to answer are:
Does posterior chamber AGV implantation effectively lower intraocular pressure (IOP) compared to anterior chamber implantation? Does posterior chamber AGV implantation result in less corneal endothelial cell loss and lower rates of postoperative complications compared to anterior chamber implantation?
Researchers will compare the two groups:
Intervention group: AGV implantation in the posterior chamber (ciliary sulcus) Control group: AGV implantation in the anterior chamber
Participants will:
Undergo a baseline evaluation, including ocular examination, IOP measurement, corneal endothelial cell density (ECD) and variability, visual field testing, and optic nerve imaging.
Be randomized into two groups based on a computer-generated randomization method.
Receive either posterior chamber or anterior chamber AGV implantation. Be followed postoperatively at specified intervals (1 day, 1 week, 1 month, 3 months, 6 months, 12 months) for IOP, use of glaucoma medications, visual acuity (Snellen, logMAR), corneal ECD, and endothelial cell variability (CV).
Undergo regular assessments for postoperative complications such as hypotony, choroidal detachment, hyphema, infection, and device-related issues.
Provide informed consent after explanation of potential risks and benefits of the procedure.
This study will use a prospective, randomized controlled clinical trial design, enrolling at least 29 eyes in each group, conducted at the Glaucoma Department of Ho Chi Minh City Eye Hospital from March 2024 to March 2027