Trabeculectomy is a 45-60 minute day-case glaucoma filtering operation that creates a new guarded drainage channel under a partial-thickness scleral flap, allowing aqueous fluid to drain into a small reservoir (a "bleb") beneath the upper eyelid and lowering intraocular pressure. At our partner clinics, private trabeculectomy starts from £4,800 per eye, all-inclusive of consultation, surgery, theatre, the mitomycin C antimetabolite and the intensive early aftercare the operation requires. It is the most effective way to achieve a large, durable pressure reduction when glaucoma is advanced or progressing despite maximal drops, SLT laser or MIGS.
What is a trabeculectomy?
Glaucoma damages the optic nerve, usually because the pressure inside the eye is too high for that nerve to tolerate. Eye drops, selective laser trabeculoplasty (SLT) and minimally invasive glaucoma surgery can control pressure for many patients, but when the pressure stays too high — or the field of vision keeps shrinking — a more powerful operation is needed. Trabeculectomy is that operation, and it has been refined over more than fifty years.
The surgeon creates a tiny trapdoor in the white of the eye (the sclera) and removes a small block of tissue underneath it, opening a controlled channel out of the eye. Aqueous fluid then seeps through this guarded opening and collects in a soft blister of tissue called a bleb, hidden under the upper eyelid, from where the body reabsorbs it. The flap acts as a one-way valve, so pressure falls without the eye becoming too soft.
Why eye pressure matters in glaucoma
- Pressure is the only modifiable risk factor — lowering it is the only proven way to slow glaucoma
- Damage is permanent — lost optic nerve fibres and visual field cannot be recovered, so the goal is to protect what remains
- Drops are not always enough — some eyes need pressures in the low teens that drops cannot reliably reach
- Adherence is hard — surgery removes the daily burden of multiple drop bottles
- Trabeculectomy lowers pressure the most — typically into the low-to-mid teens, further than most other procedures
Worried your glaucoma is progressing? A consultant assessment includes pressure measurement, optic nerve imaging and a visual field test to decide whether filtering surgery is right for you.
Book a glaucoma assessmentWhen trabeculectomy is the right choice
Trabeculectomy is usually recommended when glaucoma is moderate-to-advanced, when pressure remains too high on maximum tolerated drops, or when a very low target pressure is needed to protect the optic nerve. Your consultant will weigh it against the gentler alternatives below and recommend the approach matched to your stage of glaucoma.
There is no single best glaucoma operation — the right one depends on how advanced your disease is, your target pressure, previous surgery and your eye's anatomy. Your consultant will explain in detail why trabeculectomy, a shunt or a MIGS device suits your situation. You can compare the full range on our glaucoma treatment page.
What happens during trabeculectomy
Trabeculectomy is performed under local anaesthetic, often with light sedation to keep you relaxed. You stay awake but feel no pain. The operation takes 45 to 60 minutes, and you will be at the clinic for around 2 to 3 hours including preparation and recovery.
- Anaesthetic is given around the eye and the surrounding skin is cleaned with sterile solution.
- The surgeon lifts a thin partial-thickness scleral flap in the white of the eye, under the upper lid where it will be covered by the eyelid.
- Mitomycin C, an antiscarring medicine, is applied briefly and washed out — this keeps the new drainage channel open long-term.
- A small block of tissue is removed to create the guarded fistula, and the flap is closed with adjustable sutures that control the rate of drainage.
- The conjunctiva is closed to form the filtering bleb, the eye is shielded, and you rest before going home.
Recovery week-by-week
Trabeculectomy needs more aftercare than most eye operations because the new drainage channel has to be carefully "tuned" in the early weeks. Frequent reviews are part of a successful result, not a sign of trouble.
Day of surgery
Vision is blurred and the eye may feel gritty. An eye shield is worn at night. Steroid and antibiotic drops begin. No driving, bending or heavy lifting.
Week 1
Several close reviews. The surgeon may release or adjust sutures, or gently "needle" the bleb, to fine-tune the pressure. Drops are intensive.
Weeks 2-4
Vision steadily settles. Activity restrictions ease. Drop frequency is gradually reduced under guidance. Continued bleb monitoring.
Weeks 6-12
The bleb matures and pressure stabilises. Most patients return to normal activities. Many can stop or greatly reduce their glaucoma drops.
Long term
Lifelong glaucoma monitoring continues. A well-functioning bleb can keep pressure controlled for many years. Vision in the operated eye is preserved, not improved.
Cost & insurance
Our trabeculectomy prices are all-inclusive: consultation, pressure and visual field assessment, the surgery itself, theatre and hospital fees, mitomycin C, post-op drops and the intensive early review schedule. There are no hidden extras.
- Self-pay: from £4,800 per eye, all-inclusive.
- Insurance: recognised by Bupa, AXA, Aviva, Vitality, Cigna, WPA and others. We handle authorisation.
- Finance: 0% options available to spread the cost — ask our team.
See how it compares with laser, MIGS and shunt procedures on our glaucoma surgery cost page.