Trabeculectomy

Trabeculectomy is a surgical procedure for glaucoma that creates a new drainage pathway for fluid (aqueous humor) to leave the eye, lowering intraocular pressure (IOP). It's typically performed when medications and laser treatments don't adequately control glaucoma. While highly effective, trabeculectomy requires careful postoperative management and long-term follow-up.

How Trabeculectomy Works

The Problem in Glaucoma

In most glaucoma:

• Fluid (aqueous humor) is produced continuously inside the eye
• Drainage through the trabecular meshwork is impaired
• Pressure builds up
• High pressure damages the optic nerve
• Vision is progressively lost

The Solution

Trabeculectomy creates an alternative drainage route:

• A small opening (fistula) is made in the sclera (white of eye)
• Fluid drains from inside the eye to under the conjunctiva
• A "bleb" (filtering bubble) forms where fluid collects
• Fluid is absorbed into surrounding tissues
• IOP is lowered

Who Needs Trabeculectomy

Indications

• Glaucoma not controlled with maximum tolerated medications
• Intolerance or allergies to glaucoma medications
• Poor medication compliance
• Laser treatments (SLT, ALT) not effective or appropriate
• Rapidly progressing glaucoma despite treatment
• Advanced glaucoma requiring aggressive IOP lowering

Types of Glaucoma Treated

• Primary open-angle glaucoma
• Angle-closure glaucoma (after iridotomy)
• Secondary glaucomas
• Some congenital/juvenile glaucomas

The Procedure

Before Surgery

• Complete eye exam and testing
• Discussion of risks, benefits, alternatives
• May need to stop certain medications (blood thinners)
• Arrange transportation home

During Surgery

1. Local anesthesia (numbing injection around eye)
2. A conjunctival flap is created (covering tissue lifted)
3. A partial-thickness scleral flap is made
4. A small hole (sclerostomy) is created into the eye
5. Peripheral iridectomy (small opening in iris) performed
6. Scleral flap is sutured loosely (allows controlled flow)
7. Conjunctiva is closed
8. Antifibrotic agent (mitomycin C) often applied to prevent scarring

Duration: Approximately 30-60 minutes

Antifibrotic Agents

After Surgery

Immediate Recovery

• Eye will be patched initially
• Some discomfort normal
• Vision will be blurry
• Use prescribed eye drops diligently
• Avoid rubbing or pressing on the eye

First Few Weeks

• Frequent follow-up visits (often weekly or more)
• IOP monitoring
• Bleb assessment
• Possible laser suture lysis (releasing sutures to increase flow)
• Possible bleb needling if scarring
• Activity restrictions

Activity Restrictions

Postoperative Medications

• Antibiotics: prevent infection
• Steroids: control inflammation (often prolonged taper)
• May discontinue some or all glaucoma drops

What to Expect Long-Term

The Bleb

A successful trabeculectomy produces a filtering bleb:

• Appears as a raised area on the white of the eye
• Usually under the upper lid (not visible normally)
• Should be pale/white and slightly elevated
• Flat, inflamed, or vascularized blebs may be failing

Vision Changes

• Vision often reduced initially
• May improve over weeks to months
• Final vision depends on glaucoma severity
• Surgery preserves vision—doesn't restore lost vision

IOP Control

• Target IOP depends on glaucoma severity
• May still need some glaucoma drops
• Some patients are drop-free
• Success measured by IOP and stability of vision/fields

Complications

Common (Usually Manageable)

• Hypotony (low IOP)—can cause blurred vision
• Choroidal effusion—fluid behind retina
• Bleb leak—may need repair
• Cataract progression—may need cataract surgery later
• Bleb encapsulation—scarring limiting function
• Hyphema—blood in anterior chamber

Serious (Less Common)

• Bleb infection (blebitis)—requires urgent treatment
• Endophthalmitis—infection inside eye (emergency)
• Suprachoroidal hemorrhage—bleeding behind eye
• Loss of vision—rare but possible
• Failure requiring additional surgery

Late Complications

Success Rates

Effectiveness

• ~70-90% achieve target IOP at 1 year
• Success rates decrease over time
• May need additional procedures (needling, revisions)
• Better success with antifibrotics

Factors Affecting Success

Better success:

• First-time surgery
• Primary open-angle glaucoma
• Older age
• No prior eye surgery
• Good postoperative care compliance

Higher failure risk:

• Previous eye surgery
• Younger age
• Inflammatory glaucoma
• Neovascular glaucoma
• African descent (higher scarring tendency)

Alternatives

Other Surgical Options

• Glaucoma drainage devices (tubes)—similar success, different approach
• MIGS (minimally invasive glaucoma surgery)—for milder disease
• Cyclophotocoagulation—reduces fluid production
• More/different drops—if surgery not desired

Why Choose Trabeculectomy

• Proven long-term results
• Can achieve very low pressures
• May reduce or eliminate need for drops
• Appropriate for moderate/advanced disease

Living with a Trabeculectomy

Long-Term Care

• Regular eye exams (lifelong)
• Protect bleb from trauma
• Swimming goggles recommended
• Report symptoms promptly
• May need drops adjusted over time

Signs to Report Immediately

• Pain
• Redness (especially around bleb)
• Discharge
• Sudden vision decrease
• Flashes or floaters
• Feeling of fullness or pressure

Frequently Asked Questions

Will I still need glaucoma drops?

Many patients can reduce or stop drops after successful trabeculectomy. However, some still need medications to achieve target IOP. The goal is to control pressure—sometimes a combination of surgery and drops is optimal.

When can I return to normal activities?

This varies, but typically:

• Light activities: 1-2 weeks
• Most activities: 4-6 weeks
• Swimming: 4-6 weeks or as cleared
• Strenuous exercise: 4-6 weeks

Follow your surgeon's specific guidance.

Will my vision improve after surgery?

Trabeculectomy is done to prevent further vision loss, not restore lost vision. Vision may be temporarily reduced after surgery but usually returns to baseline. Glaucoma damage already present is permanent.

What if the surgery fails?

Options if initial surgery fails include:

• Bleb needling (office procedure to release scar tissue)
• Revision surgery
• Glaucoma drainage device
• Additional medications
• Other procedures

Is the bleb permanent?

The bleb is meant to be permanent and is essential for the surgery's function. It should remain for the life of the surgery. Avoid traumatizing it.

Can I fly after trabeculectomy?

Generally yes, after initial recovery (usually a few weeks). The bleb allows fluid out, so airplane pressure changes aren't typically problematic. Check with your surgeon about timing.

References