Glaucoma Surgery

Glaucoma is a group of eye diseases in which the optic nerve is gradually damaged, most often because fluid inside the eye does not drain well and the pressure rises. Glaucoma surgery improves drainage or reduces fluid production so the pressure falls to a level the nerve can tolerate. Selective laser trabeculoplasty, often shortened to SLT, uses gentle laser pulses to help the eye's natural drainage meshwork work better. Minimally invasive glaucoma surgery, or MIGS, places a tiny stent or opens the drainage channel through a small incision, often during cataract surgery. Trabeculectomy creates a new, controlled drainage route under a thin flap in the wall of the eye, forming a small fluid reservoir called a bleb under the upper eyelid. A tube shunt drains fluid through a fine tube to a small plate fixed on the eye wall. For angle-closure glaucoma, a laser opening in the iris or lens removal may be the main treatment.

Most glaucoma is first treated with eye drops, and surgery is recommended when drops are not enough. That may mean the pressure stays above the target your specialist has set, or the visual field and scans of the optic nerve keep showing progression despite treatment. Surgery is also considered when drops cause redness, irritation or general side effects, or when using several drops every day is not realistic. Laser trabeculoplasty is increasingly offered as a first treatment for open-angle glaucoma and ocular hypertension, sometimes before drops. Stents suit mild to moderate glaucoma, often in people who also need cataract surgery. Trabeculectomy and tube shunts are used for more advanced disease or when a low pressure is needed, and tubes are often chosen after a previous operation has failed. Congenital glaucoma in babies is treated mainly with surgery, and angle-closure attacks need urgent local care rather than travel.

Laser trabeculoplasty is done sitting at a microscope much like an eye examination: numbing drops are given, a contact lens is placed on the eye and the laser is applied for a few minutes. Stent procedures and the other drainage operations take place in an operating theatre under a microscope, usually with a local anaesthetic injection around the eye and light sedation, so you are relaxed and the eye cannot feel pain. In trabeculectomy, the surgeon lifts a small flap in the white of the eye, makes an opening into the eye beneath it and closes the flap with adjustable stitches, often applying a medicine that limits scarring. For a tube shunt, a small plate is stitched to the eye wall well back under the eyelid and its tube is passed into the eye, then covered with a patch of tissue. Drainage surgery usually takes 45 to 90 minutes, and you go home with a shield over the eye.

The choice of procedure depends on the type and stage of glaucoma, the target pressure, the health of the other eye, previous eye surgery, whether a cataract is present and how easily you can attend follow-up. Before treatment, the team measures the eye pressure, examines the drainage angle, tests the visual field and scans the optic nerve, and reviews which drops you use. Bring your recent visual field results, optic nerve scans and a list of all eye drops and general medicines, because these records show how the disease has behaved over time. Blood thinners may need adjusting on medical advice before drainage surgery. Some surgeons stop certain pressure drops shortly before an operation. Because the first weeks after trabeculectomy or a tube shunt need several visits, plan with the team who will continue your care at home, and share contact details between both specialists before you travel.

After laser trabeculoplasty you can usually return to normal activities the next day, with a pressure check after a few weeks; the full effect can take up to about two months. After stents, recovery is similar to cataract surgery and vision settles within days to weeks. Drainage surgery needs more time: vision is often blurred for a few weeks, steroid and antibiotic drops are used for 4 to 6 weeks or longer, and the surgeon checks the eye on the first day and several times in the following weeks, sometimes adjusting stitches or massaging the bleb to fine-tune the pressure. Avoid rubbing the eye, heavy lifting, bending with the head low and swimming until cleared. For travel, allow a few days after laser or stents and about 2 weeks after trabeculectomy or a tube shunt. Flying does not harm the eye itself, but the early checks matter, and you should keep using your other glaucoma drops exactly as instructed.

Glaucoma surgery is well established, and laser and stent procedures carry a low risk of serious problems, although their pressure lowering effect is more modest and can fade over time. Trabeculectomy and tube shunts lower the pressure more, but the risks are greater: the pressure can fall too low, the bleb can leak, bleeding can occur inside the eye, a cataract can form or progress, and scarring can cause the drainage to fail, so a further procedure is sometimes needed. A tube can occasionally wear through the covering tissue or cause double vision. People with a bleb carry a small lifelong risk of infection, so a red, painful or sticky eye with blurred vision needs urgent attention. Success is measured by a lower, stable pressure and a visual field that stops worsening. Some people can reduce or stop their drops, while others still need some. Regular checks for life remain essential.