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Patient PortalXEN Gel Stent- Filtration
A soft gelatin stent that creates controlled external drainage. Safest filtration option. Works when earlier steps are not enough.
What is XEN?
XEN is a tiny soft gel stent — about the size of a soft eyelash — that creates a new drainage pathway for fluid to escape your eye. Instead of trying to restore your eye's natural drainage pathways (like ABiC or iStent), XEN bypasses the clogged system entirely by creating an external outlet under the conjunctiva (the clear membrane covering the white of your eye).
Think of XEN as a carefully controlled bypass. It directs eye fluid out of your eye through a tiny stent into a bleb — a small bubble-like space under the conjunctiva where the fluid can be safely absorbed. The key difference from trabeculectomy: XEN creates a very small, controlled bleb instead of a larger one, which means a less invasive procedure with potential for fewer management visits and lower infection risk.
When is XEN appropriate? XEN is chosen when SLT, ABiC, iStent, or GATT/KDB have not achieved your pressure target. It offers more pressure reduction than other MIGS options but with less cutting and suturing than trabeculectomy. It is ideal for moderate to advanced glaucoma with normal anatomy.
What to expect — Before, During, and After
Before your procedure: You will be given numbing drops and sedation and a local anesthetic injection while you are sedated, (throughout the procedure you will remain awake but relaxed). Your eye will be positioned, and the surgical area will be prepped. You may feel pressure but will not experience pain.
During the procedure: Your surgeon creates a small opening in your the thin tissue covering of your eye under the eyelid using specialized instruments. A tiny soft gel stent that looks like a microscopic strand of spaghetti that is hollow in the center is inserted into the eye and vents fluid to under the skin of the eye . The entire procedure is microscopic — you will not feel the stent being placed. Total time is 30 minutes.
After the procedure: Your eye will feel tender and slightly irritated. Vision will be blurry for several days. You will use antibiotics and anti-inflammatory drops for 4–8 weeks. Postop injections and needling will be performed as needed to keep the bleb functional.
Recovery timeline
- Day 1: Mild discomfort and blurriness expected. Use prescribed drops. Avoid driving and strenuous activity.
- Week 1: Continue antibiotics and anti-inflammatory drops. Vision improving. Keep activities limited for 1–2 weeks total.
- Weeks 2, 4, 6, 8: Regular follow-up visits at these intervals. Bleb assessment, postop injections, and needling performed as needed.
- Week 12: Final postop assessment. Bleb stabilization confirmed. Continue drops 4–8 weeks depending on inflammation level. Return to routine glaucoma schedule.
Bleb care is important. A small percentage of patients develop bleb infection (bleb-related endophthalmitis) months to years after XEN. While rare — less than 1% over the lifetime of the bleb — infection risk requires you to: (1) avoid eye trauma, (2) promptly report any redness or pain, (3) seek prompt care if you notice sudden vision loss with pain.
Your follow-up schedule
XEN requires more follow-up visits than SLT or ABiC. This is because the bleb needs monitoring to ensure it stays open and functional.
What we are watching for:
- Bleb appearance (size, vascularity, encapsulation)
- Inflammation and scarring
- Pressure control
- Stent function and position
- Any signs of infection or complications
Anti Scarring Injection: Most patients will require an injection of anti scarring medication that is done in the office exam chair after topical anesthetic. Most patients are not aware of any pain with this medicine and the amount is quite small. This prevents your body’s natural healing process from closing off the stent.
Bleb needling — when it becomes necessary
Approximately 15% of XEN patients eventually need bleb needling at EPSAZ (national levels are 30%) — a brief in-office procedure where we revive a bleb that has become sealed or scarred. This is not a failure; it is a normal part of how blebs evolve. If your bleb seals, needling can restore flow without requiring a second surgery.
What is bleb needling? Using a fine needle, we gently puncture the scarred bleb tissue to reopen the drainage pathway. You receive numbing drops; the procedure takes 5–10 minutes. Most patients see improved pressure control within days.
Good news: Needling can be repeated. If your bleb seals again months or years later, we can needle it again. Some patients have had needling 2–3 times over the years and maintained good pressure control.
Our outcomes — what EPSAZ patients experience
Here is what we see in our database of 394 patients who had XEN, followed for 12 months:
What these numbers mean: XEN achieves about 23% pressure reduction — significantly more than MIGS options. Patients typically eliminate 1–2 medications. The safety rating reflects the bleb management burden and the 15% needling rate, not dangerous complications. Most needlings are brief and simple.
Who does well with XEN? Patients with moderate to advanced glaucoma, normal corneal anatomy, and good general health are ideal. Patients who can commit to follow-up visits during the first 6 months (bleb needling may be needed). Patients who understand that XEN is more invasive than MIGS but less intense than trabeculectomy.
What if XEN does not control pressure? If your pressure remains above target even after bleb needling, we discuss tube shunt as the next option — a more advanced step on the R's Framework.
Bleb management: The first 6 months after XEN are critical. The bleb can scar down (encapsulation), become overfiltering, or develop infection. We monitor bleb appearance (elevation, vascularity, integrity), eye pressure, and signs of inflammation at every visit.
Bleb-related endophthalmitis: The most serious late complication is bleb infection. While rare, it can occur months or years after surgery. To minimize risk: avoid eye trauma, report any redness or pain immediately, and seek urgent evaluation if you develop sudden vision loss with pain.