A trabeculectomy is a standard surgery performed to treat patients with moderate-to-severe glaucoma. This surgical procedure lowers internal eye pressure, or intraocular pressure (IOP), when medications, laser therapy, and less invasive types of surgery have been insufficient. A trabeculectomy is considered to be a “gold standard” procedure, so here’s what you need to know about this common glaucoma surgery.*

What happens during a trabeculectomy?

The surgery will take place in an operating room, where an anesthesiologist will administer local anesthesia to the eye before the surgery.

During the procedure, a small hole is made in the wall of the eye to redirect fluid drainage away from the obstruction in the trabecular meshwork, the eye’s natural drainage structure. After the hole is made, a flap is created over the hole to control the flow of drainage. 

The creation of the hole and flap forms a small blister, called a “bleb,” beneath the upper eyelid. The bleb is not usually visible to others unless you point it out. 

The entire operation takes approximately an hour to complete.

After surgery

After the surgery, patients will generally stop their old glaucoma medications and begin taking antibiotics and steroid eye drops to control inflammation and prevent infection. 

You may find the bleb will start to scar over as part of your body’s natural healing process. While surgeons often use anti-scarring medications during the procedure to prevent this problem, it can still sometimes occur. 

Your doctor can inject anti-scarring medications during a post-op office visit to help control the scarring process. If scarring has already occurred, your surgeon can also try breaking up the scar tissue during an office visit. 

On rare occasions, further surgery may be required.

Recovering from a trabeculectomy

Recovery from a trabeculectomy can take anywhere from two to six weeks. Keeping your follow-up appointments is critical during this period. A variety of potential complications can be managed, and averted, during these visits. 

In addition to the anti-scarring injections mentioned above, your doctor may also need to:

• Suture the flap
• Release the flap
• Demonstrate a specific eye massage technique to control the bleb formation

What are some possible complications?

Trabeculectomy has a 60% to 80% success rate in controlling eye pressure for five years. While complications are rare, they can occur. 

Some known side effects and complications of trabeculectomy include:

• Infection in the eye
• Bleeding inside the eye
• Loss of vision
• Eye pressure that is too low
• Acceleration of cataract formation (though cataract surgery can be concurrent)
• Bleb growing large enough to become noticeable or cause discomfort

The anti-scarring medications can increase the risk for an eye infection, even years following the surgery. Call your doctor right away if you experience:

• Discomfort
• Abnormal tearing
• Pus-like discharge
• Increasing redness

Early treatment of an infection can help preserve your vision.  

Other options

A variation of the surgery is to create the bleb using an EX-PRESS shunt, a small metal shunt inserted into the eyewall. Some studies have shown this method to result in faster vision recovery and less post-procedure inflammation. 

Disadvantages can include needing to remove the shunt in case of infection and possible long-term damage to your cornea if the shunt is not placed properly. The metal shunt does not affect MRI scans or airport security.

Speak with your surgeon about the best option for your particular situation. 

*Ou, Y. (2018, Apr. 23). Glaucoma Surgery Series: Trabeculectomy. BrightFocus Foundation. https://www.brightfocus.org/glaucoma/article/glaucoma-surgery-series-trabeculectomy

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