What is a Trabeculectomy?
A trabeculectomy is a surgical treatment for glaucoma. The surgery aims to lower intraocular pressure (IOP) by creating a new pathway for fluid drainage.

Glaucoma is an eye disease that occurs when the fluid inside the eye (aqueous humor) doesn’t drain normally. Over time, the fluid builds up and increases IOP inside the eye, which damages the optic nerve.
Uncontrolled glaucoma leads to a loss of peripheral vision and possibly central vision. Without treatment, this disease can cause complete blindness.
The goal of trabeculectomy is to reduce or prevent the loss of vision. However, this surgery cannot cure or restore lost vision.
Who Needs a Trabeculectomy?
Trabeculectomy is a common treatment option for several types of glaucoma, including:
- Closed-angle glaucoma
- Open-angle glaucoma
- Primary glaucoma
- Secondary glaucoma
Your doctor may recommend a trabeculectomy if other treatments, such as glaucoma medications or laser surgery, cannot lower your IOP.
What to Expect from a Trabeculectomy Procedure
Trabeculectomy is typically an outpatient procedure, meaning you can go home the same day. The surgical procedure usually takes about an hour.

Your eye doctor will give you instructions to help prepare for surgery. These instructions include a time to stop eating and drinking, among other protocols. If you don’t follow the instructions closely, your doctor might cancel the surgery for safety reasons.
Preparing for Surgery
Educating yourself about glaucoma will help you prepare for the surgery. Also, confirm what your insurance plan covers to avoid surprise charges and copayments.
A few helpful questions to ask your eye doctor before surgery include:
- Do I need to stop taking any daily medications or supplements before surgery?
- Before surgery, do I need to fast (not eat or drink anything)?
- Will I be receiving conscious sedation or general anesthesia?
- How long does recovery take?
- Do I need someone to take care of me after surgery?
- How will I know if the surgery was successful?
If the trabeculectomy occurs in an outpatient clinic, ensure you have a designated driver to take you home. Remove makeup, leave your contact lenses at home, and wear comfortable clothing and shoes.
During Surgery
On the day of trabeculectomy surgery, you can expect the following:
- You may receive medicine to relax (conscious sedation) if you’re awake during the procedure. You’ll also receive an anesthetic to numb the eye so you won’t feel anything. Sometimes, you may receive general anesthesia and sleep through the surgery.
- The surgeon will clean your eye and use a speculum to hold it open.
- The surgeon creates a flap in the white part of your eye (sclera) beneath your upper eyelid.
- Under the flap, they create a new channel for fluid drainage from inside your eye.
- They carefully replace the flap and cover the surgery site with the clear covering of your eye (conjunctiva).
- This creates a small blister of fluid (bleb) on top of your eye. The bleb is underneath your eyelid, so it isn’t visible.
- Your body reabsorbs the fluid inside the bleb, which lowers your eye pressure to a normal level.
- The surgeon uses sutures to close the scleral flap.
After Surgery
Most people can go home on the same day. However, you’ll need someone to drive you home. Your doctor will tell you when you can drive again.
Recovery from a trabeculectomy can take 4 to 6 weeks and may include:
- Soreness or redness around the eye
- Frequent follow-up visits will occur to monitor eye drainage
- Avoiding lifting, bending, and vigorous exercise
- Blurry vision for up to 6 weeks
- Wearing an eye shield while you sleep to avoid accidental injury
- Avoiding wearing contact lenses and eye makeup while your eye heals
- Avoiding swimming, gardening, and dusting for 2 weeks
Your doctor will prescribe steroid eye drops and other medications. These prevent infection, reduce inflammation, and minimize scarring of the bleb. You should use these as directed by your doctor.
What are the Risks of a Trabeculectomy?
Trabeculectomy surgery is considered safe and effective. However, there’s some risk of complications, such as:
Failure to Control Eye Pressure
Scar tissue around the surgical site can prevent fluid flow from inside the eye. If this happens, your surgeon may recommend a revision or a different surgery to lower eye pressure.
Blurry Vision from Low Eye Pressure
Excessive fluid drainage from inside the eye can cause pressure to drop too far and cause blurry vision. This may be temporary, or it may require additional surgery.
Bleb Leaks
A bleb leak can occur right after surgery or months after the eye heals. This may resolve on its own, or you may need another surgery to stop the leak.
Bleeding Inside the Eye
Bleeding can result from the surgery itself or low eye pressure. Rarely, eye bleeding can cause vision loss.
Eye Infections
An infection may develop at the surgery site. Without prompt treatment, the infection can enter the eye and cause vision loss.
Cataracts
Trabeculectomy can speed up the development of cataracts. A cataract is when the normally clear lens of the eye becomes cloudy. Cataract surgery is a common and highly effective way to treat this.
Trabeculectomy Success Rates
Trabeculectomy surgery is an effective procedure for reducing intraocular pressure and preserving vision.
The long-term success rate of trabeculectomy is close to 90%.5 Most people can stop taking glaucoma medications since their eye pressure stays controlled after surgery.
The trabeculectomy outcome is good with a timely follow-up and close monitoring by an eye doctor.
Alternative Surgical Options
Trabeculectomy isn’t the only type of glaucoma surgery available. Other options include:
- Stents placed inside or outside of the eye to direct aqueous flow
- Procedures to unblock the eye’s natural drain
- Laser procedures that slow the speed of fluid production inside the eye
As with any ocular surgery, discussing your options with your eye doctor is important.
Summary
Trabeculectomy surgery treats various types of glaucoma. Glaucoma develops when the eye's intraocular pressure becomes too high and causes optic nerve damage. If not treated, glaucoma can cause blindness.
Trabeculectomy surgery aims to preserve vision by lowering the eye's intraocular pressure (IOP). It involves creating a new channel for fluid to drain.
Though considered a safe and effective procedure, trabeculectomy has some risks. Surgical complications include bleeding, leaking, and infections.
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