XEN Gel Stent vs Trabeculectomy
When Surgery Becomes Necessary for Glaucoma
Your eye pressure may need surgical control if it stays too high despite maximum medical therapy. We watch for progressive vision loss or optic nerve damage that continues even when you use multiple eye drops correctly.
Other red flags include pressure readings consistently above your target goal, worsening visual field tests over time, or increasing cupping of the optic nerve head. If you cannot tolerate the side effects of glaucoma medications, surgery may become the safer path forward.
Some types of glaucoma simply do not respond well to drops or laser procedures. Advanced glaucoma often requires a stronger intervention to prevent blindness.
- Your drainage system may be too damaged for laser treatment to work
- Multiple medications together may still leave pressure too high
- Side effects from drops may prevent you from using enough medicine
- You may have trouble remembering or affording daily eye drops
High eye pressure damages the optic nerve, which carries visual signals from your eye to your brain. This damage is permanent and cannot be reversed.
Without surgical treatment, uncontrolled pressure leads to gradual narrowing of your side vision, then tunnel vision, and can progress to severe vision loss, including loss of central vision. The speed of vision loss varies, but catching it early with surgery preserves the sight you still have.
Understanding Your Two Surgical Options
The XEN Gel Stent is a tiny tube about the width of a human hair made from soft gelatin material. The implant is made of crosslinked porcine-derived gelatin and is about 6 mm long with a microscopic inner channel.
Your ophthalmologist inserts this microscopic stent through the white part of your eye to create a new drainage pathway for fluid. The stent stays permanently in your eye and allows aqueous humor (the clear fluid inside the eye) to flow from inside the eye to a space beneath the conjunctiva (the clear outer covering), where the fluid absorbs into surrounding tissue. XEN can be implanted ab interno from inside the eye or ab externo with an open conjunctival approach. Many surgeons use intraoperative antimetabolite medication to limit scarring.
Trabeculectomy is a traditional filtering surgery that creates a new drainage channel in your eye. We remove a small piece of tissue from the eye wall to make an opening, then create a protective flap over it.
This opening allows fluid to drain into a bleb, which is a small blister-like reservoir that forms under the upper eyelid. The tissue around the bleb gradually absorbs the fluid, lowering pressure inside the eye. We usually apply an antimetabolite such as mitomycin C during surgery and may supplement with 5-fluorouracil injections after surgery to reduce scarring.
Both surgeries bypass your eye's natural drainage system to create an alternate route for fluid to leave the eye. They work by allowing aqueous humor to filter into the space between the white of your eye and the clear outer covering.
- Both create a drainage pathway through the eye wall
- Both form a fluid collection area under the conjunctiva
- Both rely on surrounding tissue to absorb the drained fluid
- Both achieve lower pressure than most patients get with drops alone
XEN and trabeculectomy are not the only surgical options for lowering eye pressure. Depending on your glaucoma type, severity, and eye health, other procedures may be safer or more effective for you.
- Tube shunt surgery that drains fluid through a small implanted plate and tube
- Angle-based MIGS combined with cataract surgery for selected mild to moderate cases
- Cyclophotocoagulation options for eyes not suited to incisional filtration
- Your surgeon will explain when these may be safer or more effective than XEN or trabeculectomy
Who Gets Which Procedure
We perform a comprehensive eye exam to measure your current pressure, assess optic nerve damage, and test your visual field. These baseline measurements help us track surgical success and choose the right procedure for you.
We also review your medical history, current medications, and any previous eye surgeries or conditions. A detailed look at the front of your eye with special imaging helps us plan the safest surgical approach.
- Gonioscopy to assess the drainage angle and determine glaucoma type
- Central corneal thickness measurement to interpret pressure readings
- Optic nerve imaging and photographs for structural baseline
- Macular and retinal nerve fiber layer scans to quantify damage
- Anterior segment evaluation including conjunctival health and lens status
XEN Gel Stent is most often considered when medications and prior treatments have not achieved target pressure. Many surgeons also consider XEN for selected patients who need pressure targets in the mid-teens with a less invasive bleb-forming procedure. If used earlier in the disease course, this may be outside the device's labeled indication and will be discussed with you.
- Your glaucoma is progressing but not yet severe
- You want a less invasive option with faster recovery
- Your eye anatomy allows clear access for stent placement
- You have open-angle glaucoma rather than other types
- Reasonable when your target pressure is in the mid-teens and a bleb-based approach is acceptable
Trabeculectomy remains our go-to choice for advanced glaucoma that requires very low target pressures. This procedure generally achieves lower final pressures than the XEN stent.
We lean toward trabeculectomy if you have severe optic nerve damage, pressures far above normal, prior failed glaucoma surgeries, or certain types of secondary glaucoma. The longer track record of trabeculectomy also guides our recommendation when we need the most proven pressure reduction. In some eyes, particularly with extensive scarring, neovascular or uveitic glaucoma, or after prior surgeries, a tube shunt may be a better option than trabeculectomy.
Patients with advanced glaucoma and little remaining vision usually need the strongest pressure lowering possible, which typically means trabeculectomy. The more aggressive approach reduces the risk of further vision loss when you cannot afford any additional damage.
If your glaucoma is caught earlier and you retain good vision, the XEN stent may provide enough pressure reduction while offering a gentler recovery and lower complication rates. We balance the urgency of your condition against the invasiveness of the surgery.
Previous cataract surgery, corneal problems, or inflammation in your eye can affect which procedure works best. Extensive conjunctival scarring from prior surgeries may limit where we can place either a stent or a trabeculectomy flap.
- Heavy scarring may favor trabeculectomy in a different location
- Thin or fragile conjunctiva may increase the risk of erosion or leaks with bleb-forming surgery. Your surgeon may select a different location or consider a tube shunt
- Active inflammation usually requires control before either surgery
- Combined cataract and glaucoma surgery may change the plan
Gonioscopy findings, scarring risk, and your ability to attend frequent follow-up visits are major factors in the choice.
The Procedure Experience: What to Expect
On surgery day, we numb your eye completely so you feel no pain during the procedure. The XEN stent placement typically takes about 15 to 30 minutes from start to finish.
Your ophthalmologist uses a special injector to insert the tiny stent through the white part of your eye from an internal approach. You remain awake but comfortable throughout the brief procedure, and we place a protective shield over your eye afterward. Your surgeon may use either an ab interno or an ab externo open-conjunctival technique based on your conjunctival health and scarring risk.
Trabeculectomy takes slightly longer than XEN placement, usually 45 minutes to one hour. We numb your eye thoroughly and may also provide relaxing medication to keep you calm.
During surgery, we create a partial-thickness flap in the white of your eye, remove a small piece of deeper tissue to make the drainage opening, and carefully close the flap with tiny sutures. We often apply anti-scarring medication to help the new drainage channel stay open, and finish by positioning the conjunctiva over the surgical site. We may use laser suture lysis in the early postoperative period to fine-tune flow.
Both procedures use local anesthesia. XEN is often performed with topical drops and sometimes a small numbing injection near the eye. Trabeculectomy typically requires a peribulbar or sub-Tenon's block. You remain awake with light sedation.
- We may offer oral or IV sedation to help you relax
- If a numbing injection is used, it may cause brief stinging before taking effect
- XEN placement often requires less deep anesthesia
- After surgery, mild discomfort responds well to over-the-counter pain relief
Both procedures happen on an outpatient basis, meaning you go home the same day. Your total time at the surgery center includes preparation, the operation itself, and a brief recovery period.
Plan for about two to four hours at the facility for either surgery. You cannot drive yourself home because your eye will be patched and your vision blurred, so arrange for a family member or friend to take you. Your operated eye is usually patched and shielded until the first follow-up.
Recovery and Aftercare Comparison
Most patients notice significant improvement within one to two weeks after XEN stent placement. Your eye may feel scratchy or mildly irritated for the first few days.
Vision often remains blurry for several days as the eye adjusts and heals. By four to six weeks, many patients reach their final pressure result and complete most of the healing process. An in-office needling procedure to break up scar tissue is commonly performed in the first weeks if pressure rises.
Trabeculectomy requires a longer and more monitored recovery period. The first two weeks demand careful attention to protect the delicate surgical site and prevent infection.
Vision typically takes three to six weeks to stabilize as the bleb forms and matures. Final pressure results may take up to three months as the drainage pathway settles into a long-term balance between filtering enough fluid and avoiding over-drainage. Vision fluctuations are common while the bleb matures and sutures are adjusted or lysed.
After either surgery, you will use antibiotic and anti-inflammatory eye drops for several weeks. These medications prevent infection and control inflammation that could cause scarring.
- Steroid drops reduce swelling and prevent excessive scarring
- Antibiotic drops guard against infection during healing
- The drop schedule gradually tapers over weeks to months
- Trabeculectomy often requires a longer steroid taper than XEN placement
- You may restart some glaucoma drops if needed for additional pressure control
- Your doctor may perform in-office 5-fluorouracil injections to limit scarring, especially after trabeculectomy
- Steroid drops can raise eye pressure in some patients. Do not change or stop drops without your surgeon's guidance
Avoid heavy lifting, straining, and bending over for at least two weeks after either surgery. These activities raise pressure in your eye and can damage the healing surgical site.
Keep water, soap, and makeup away from your eye for the time period we specify. Wear your protective eye shield at night to prevent accidental rubbing or bumping while you sleep, and avoid swimming or hot tubs until we give you clearance.
- Avoid contact lens wear in the operated eye until cleared. Some patients with a filtering bleb cannot comfortably wear a contact lens long term on that eye
We typically see you the day after surgery, then again at one week, two weeks, one month, and three months. These visits let us monitor your pressure, check for complications, and adjust medications.
Trabeculectomy patients often need more frequent early visits because we may adjust or remove sutures to fine-tune drainage. XEN patients usually require fewer adjustments but still need close monitoring to ensure the stent functions properly. XEN patients may need earlier visits if needling or bleb revision is needed.
Many XEN stent patients return to desk work within a few days to one week. Trabeculectomy patients often need one to two weeks before resuming light work activities.
- Avoid strenuous exercise for three to four weeks after either surgery
- Skip activities that risk eye injury for at least six weeks
- You can usually drive once your vision clears and we give approval
- Contact sports should wait until complete healing at three months
Success Rates, Risks, and Complications
Trabeculectomy typically achieves lower final eye pressures than XEN stent placement, often reaching the low teens or even single digits. This makes it the preferred choice when you need very aggressive pressure reduction.
The XEN Gel Stent usually lowers pressure into the mid-teens, which is sufficient for many patients with less severe glaucoma. Success rates for adequate pressure control range from 60 to 80 percent for XEN and 70 to 90 percent for trabeculectomy, depending on how we define success. Success is defined by whether you reach your individualized target pressure with or without medications and maintain stable vision. Outcomes vary based on your baseline pressure, glaucoma type, prior surgeries, and use of antimetabolites.
Both procedures can maintain lower pressure for many years when they work well. Trabeculectomy has decades of long-term data showing sustained pressure control, though the effect may gradually diminish over time.
The XEN stent is newer, with strong data showing good pressure control for at least five years in most successful cases. Both surgeries may eventually lose effectiveness as scarring or drainage changes occur, sometimes requiring additional treatment.
The XEN stent can migrate out of position, become blocked, or erode through the overlying tissue. These complications may require stent removal or revision surgery.
- The stent may not lower pressure enough and need additional procedures
- Excessive scarring around the stent can block drainage
- The implant may become visible or irritating under the eyelid
- Pressure may drop too low temporarily, causing blurred vision
- Because XEN creates a filtering bleb, bleb leaks and bleb-related infections such as blebitis or endophthalmitis can occur, although uncommon
- In-office needling or revision is frequently needed early to maintain flow
Trabeculectomy carries risks of infection, bleeding inside the eye, and excessive drainage that causes very low pressure. The bleb can leak, become infected, or scar closed over time.
Cataract formation accelerates after trabeculectomy in many patients. Very low pressure can lead to vision changes, fluid in the back of the eye, or even damage to the optic nerve from too little blood flow, though these serious complications are uncommon with careful monitoring.
- Hypotony maculopathy, especially in younger or highly myopic patients
- Choroidal effusion or, rarely, choroidal hemorrhage
- Bleb leak and bleb-related infections including blebitis or endophthalmitis
- Bleb dysesthesia or localized corneal drying (dellen)
- Ptosis or double vision in some cases
Contact your ophthalmologist immediately if you experience sudden vision loss, severe eye pain that does not improve with prescribed medication, or increasing redness and swelling. These symptoms may signal serious complications that need urgent treatment.
- Sudden decrease in vision or new floaters and flashes
- Severe, worsening pain not controlled by pain relievers
- Discharge, crusting, or pus coming from your eye
- The white of your eye becoming much redder instead of improving
- Feeling like a curtain is closing over your vision
- A sudden watery leak from the surgical area or a constantly wet eye patch
Frequently Asked Questions
Yes, if XEN stent placement does not achieve sufficient pressure lowering, we can still perform trabeculectomy in many cases. Going the opposite direction is also possible but may be more complicated if scarring from trabeculectomy limits stent placement options.
Many patients significantly reduce their drop burden or eliminate medications entirely after successful surgery, but some still need one or two drops to reach target pressure. The goal is better control with less medication rather than guaranteed freedom from all drops.
XEN Gel Stent placement generally offers a quicker and more comfortable recovery, with most patients resuming normal activities within one to two weeks. Trabeculectomy demands a longer healing period and more careful activity restrictions for the first month. Your surgeon's guidance prevails, since activity limits and visit frequency are individualized.
Yes. Tube shunts are often recommended in eyes with significant conjunctival scarring, certain secondary glaucomas, or after prior glaucoma surgeries. Your surgeon will explain when a tube may be safer or more effective than XEN or trabeculectomy.
Costs vary based on your insurance coverage, facility fees, and geographic location. The XEN stent itself adds device cost, while trabeculectomy may involve more operating room time and post-operative visits, making total expenses similar for many patients.
We do not typically perform both glaucoma surgeries in the same eye on the same day because they work through similar pathways and layering them offers no advantage. If both eyes need surgery, we usually space them weeks apart to monitor results and avoid simultaneous recovery in both eyes.
If pressure rises again after initial success, we have several options including laser treatment to the surgical area, needling procedures to break up scar tissue, adding or adjusting eye drops, or performing another surgery in a different location. Each case requires individual assessment to determine the best next step.
Getting Help for XEN Gel Stent vs Trabeculectomy
If your glaucoma is progressing despite current treatment, schedule an appointment with your ophthalmologist to discuss whether surgical options might protect your vision more effectively. We will evaluate your specific situation, explain which procedure best matches your needs, and answer all your questions to help you make an informed decision about your eye health. This information is general education and does not replace advice from your ophthalmologist about your specific condition.