Glaucoma
What is a glaucoma drainage device?
A glaucoma drainage device, sometimes called a tube or shunt, is a small implant that carries fluid from inside the eye to a plate placed on the outer wall of the eye, where the fluid is absorbed. It is used when trabeculectomy has failed or is likely to fail, and in complex or secondary glaucoma. It lowers pressure but does not restore lost vision.
Who it suits
- Eyes where a previous trabeculectomy has scarred closed
- Glaucoma after injury, inflammation or previous complex eye surgery
- Neovascular glaucoma, including cases related to diabetes
- Eyes with extensive conjunctival scarring that makes a bleb unlikely to survive
The procedure and early weeks
Under local anaesthesia and an operating microscope, the plate is secured to the outer wall of the eye behind the lid and a fine tube is passed into the front chamber, covered with a graft for protection. Some devices are designed to restrict flow at first, and others are temporarily tied off, so pressure may not fall for several weeks until flow opens up.
Expect blurred vision for some weeks, drops to control inflammation and infection, and regular review visits while the eye settles.
Risks and follow up
Possible problems include double vision from the plate affecting eye movement, the tube shifting or becoming exposed, corneal changes, pressure that falls too low early or rises again later as tissue thickens around the plate, and infection. Lifelong monitoring is needed, and additional drops are sometimes still required. As with all surgery, results cannot be guaranteed.
When to seek urgent assessment
- Pain, redness, discharge, sudden blurring or double vision after drainage device surgery, which needs prompt assessment
Frequently asked questions
- Can the device be seen or felt?
- The plate sits behind the eyelid and is not usually visible. Some people feel mild awareness for a few weeks.
- Is it permanent?
- Yes, the implant stays in place. It is removed only in the uncommon event of a complication.
Concerned about these symptoms?
Arrange an eye examination with our consultant ophthalmologist in Garki, Abuja.
Care at Standard Eye
Related answers
- When is glaucoma surgery needed?
- What is a trabeculectomy?
- What is MIGS, or minimally invasive glaucoma surgery?
- What is eye pressure, and what is a normal reading?
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