Glaucoma: Surgical Treatment Options

Glaucoma refers to a group of eye disorders which can damage the optic nerve. It is a common condition in adults in which fluid cannot drain properly from the eye. The fluid builds up at the front of the eye, putting pressure on it and damaging the optic gradually. This is called intraocular pressure (IOP). Glaucoma can affect one or both eyes.

If glaucoma isn’t treated or managed properly, it can lead to irreversible and permanent vision loss. Glaucoma treatments are available which can slow down the progression of vision loss and save your eyesight.

Treatments include prescription eye drops, implants, laser therapy and surgery.

Glaucoma surgery

Surgery may be an option for some patients to lower pressure and prevent further damage to the optic nerve and vision. Glaucoma surgery improves the drainage of the fluid by either making it easier for it to flow or by reducing the amount of fluid your eyes make.

This page explores surgical options for the treatment of glaucoma.

Laser surgery for glaucoma

Laser trabeculoplasty: The most common type of surgery to treat glaucoma, the procedure either uses an argon laser trabeculoplasty (ALT) or a selective laser trabeculoplasty (SLT). Laser therapy may be recommended in addition to medical treatment. The lasers reduce the pressure in the eye by removing the blockage in the eye’s drainage system (trabecular meshwork). SLT is a newer type of laser that is more targeted, selective and repeatable.

Laser peripheral iridotomy (LPI): The laser makes a small hole in the iris (the colored part of the eye) to allow fluid to move freely. This type of laser is suitable for people with closed-angle glaucoma.

Cyclophotocoagulation (CPC): The laser in this procedure causes the ciliary body to make less fluid. It is often performed on patients who already have low vision and glaucoma. CPC can be performed in two ways:

• Transscleral CPC: The laser is applied outside of the eye, either with a continuous treatment or via an on/off application. Transscleral CPC is usually given to patients who haven’t responded well to other treatments.
• Endoscopic CPC: This is often offered to patients undergoing, or who have previously had, cataract surgery.

Incisional glaucoma surgery

Trabeculectomy: This procedure involves creating an opening in the sclera (the white part of the eye) to intentionally damage part of the trabecular meshwork. The opening in the sclera allows fluid to move, bypassing the eye’s normal drainage system, and lowering eye pressure.

Goniotomy: Involves cutting the first layer of the trabecular meshwork, allowing fluid to leave the eye more freely. Goniotomy and trabeculectomy are commonly used to treat glaucoma in children.

Tube shunt: An incision is made at the point where the sclera and cornea meet, and a small tube is placed into the opening. An advanced, minimally invasive option called PreserFlo MicroShunt® procedure is now available, which involves inserting a small biocompatible stent into the drainage system of the eye. This shunts intraocular fluid and immediately lowers pressure inside the eye. The advanced procedure effectively treats progressive damage caused by glaucoma, supports faster recovery and reduces the reliance on medication. Cleveland Clinic Abu Dhabi was the first hospital in the region to offer this procedure.

Minimally invasive glaucoma surgery (MIGS): Suitable for patients with mild or moderate glaucoma, this advanced technology uses tiny devices and instruments, resulting in smaller incisions, faster recovery and for some patients, allows them to undergo treatment earlier in the disease. MIGS can be performed at the same time as cataract surgery. A procedure called iStent is a commonly performed MIGS, in which two tiny stents (hollow titanium tubes) are inserted into the trabecular meshwork, allowing fluid to drain and reducing pressure in the eye.

Revision glaucoma surgery

Revision glaucoma surgery is most needed when intraocular pressure has not been adequately controlled by previous surgery, when the initial surgery has caused closure or scarring of the drainage pathways, or when cataracts have developed. The decision to proceed with revision glaucoma surgery involves a thorough evaluation of the patient's current eye health, the reasons for the failure of the initial surgery, and the risks and benefits of undergoing another surgical procedure.

This decision-making process is collaborative, involving both the patient and a team of experienced ophthalmologists or glaucoma specialists. Revision surgeries can be more challenging than initial procedures due to alterations in the eye's anatomy and the presence of scar tissue. Therefore, they carry certain risks, including infection, further scarring, and potential damage to the eye, which could lead to vision loss. The specific risks depend on the type of revision surgery being considered. Post-surgery care and monitoring are crucial to ensure the success of the procedure and to manage any complications early.

Types of revision glaucoma surgery include:

Scar revision or needling: If scarring has blocked the drainage pathway created by a trabeculectomy or a tube shunt procedure, a revision may involve removing or reducing the scar tissue.

Enhancement of existing procedures: Additional laser treatments may be applied to enhance the drainage in procedures such as trabeculectomy or to improve the functioning of a drainage implant.

Replacement or repositioning of implants: In cases where a glaucoma drainage device is not functioning properly, it may need to be repositioned, replaced, or supplemented with another device.

Secondary surgery: If the initial surgery was not successful or its effects have diminished over time, a different type of glaucoma surgery may be recommended as a revision strategy.

Preparing for glaucoma surgery

Ahead of any glaucoma surgery, your doctor will discuss the procedure with you in detail and talk to you about expectations. They will discuss your medical history and give you a list of pre-operative instructions. It is very important that you follow these closely.

Most laser surgeries are performed in the doctor’s office, and you can go home the same day. Incision surgeries such as trabeculectomy, MIGS, tube shunt and CPC will be performed in an operating theatre. You will either be sedated or be put under general anesthesia.

Laser procedures usually only take a few minutes, while incision surgeries can take up to an hour.

Recovery times vary, and your doctor will discuss this with you before you return home. Always contact your doctor if you have any questions or concerns about glaucoma surgery.

Every case of glaucoma is different. A multidisciplinary team of experts will discuss your options with you thoroughly to ensure you are offered personalized care and the best results.