When medicated eye drops and laser surgery do not remedy intraocular pressure (IOP), your doctor may recommend conventional glaucoma surgery. The most common surgical option is trabeculectomy, also called filtration surgery. During the procedure, your surgeon will create a tiny opening in the sclera (the white part of the eye) covered by a thin trap door. The excess aqueous humor (the clear fluid between your eye’s lens and cornea) drains through the trapdoor to a small reservoir just under the eye surface, hidden by the eyelid. This will lower intraocular pressure and slow the effects of glaucoma.
About half of all trabeculectomy patients do not require glaucoma medication for a considerable amount of time after surgery. While effective at reducing IOP, this procedure is not considered a cure, and people can still experience vision loss even after surgery. Vision loss usually happens if the procedure fails which happens when your body heals too aggressively and closes the hole that the surgeon created. It’s important to work with your doctor to create a treatment plan and follow up schedule that is right for you.
What Happens During Trabeculectomy?
Several eye drops will be administered before surgery begins. Your eye will be sterilized and you will receive local or even topical anesthetic.
The goal of trabeculectomy is to create a filtration system for the buildup of aqueous humor so the intraocular pressure is diminished. This is done by removing a piece of your eye tissue from the drainage angle of the eye to create an opening. The outer white coating of your eye, called the sclera, is cut open to make a flap for the aqueous humor to drain.
A filtration reservoir called a bleb is created under the thin membrane called the conjunctiva that covers the white part of your eye. The trapped aqueous humor can now circulate and drain through the flap and collect in the bleb. The fluid will be absorbed into the surrounding blood vessels and intraocular pressure will decrease. Your surgeon will then close the scleral flap and conjunctiva with sutures.
What to Expect
Most trabeculectomy procedures are done at outpatient surgery centers with minimal prep. Your surgeon will ask for a list of your prescription medications to review before the surgery and will make any necessary recommendations. Some discomfort is normal after surgery, and temporary side effects like blurry vision and sensitivity to light are common.
You will need to wear a protective eye shield while sleeping during recovery. Your doctor will prescribe antibiotics and corticosteroids (anti-inflammatory eye drops) that you will use for a significant length of time after the procedure. You may need to take additional medication to reduce scarring.
Outcomes of Trabeculectomy
About half of all trabeculectomy patients do not require glaucoma medication for a considerable amount of time after surgery. Many patients will experience a significant decrease in their IOP. The number of post-op visits will vary from patient to patient, and you should plan to limit certain activities such as driving, reading, bending and straining for 2 to 4 weeks after surgery.
Although trabeculectomy has been proven to reduce intraocular pressure in most patients, many individuals need more trabeculectomy surgery as well as other glaucoma treatments. This procedure is not considered a cure, and people can still experience vision loss even after surgery. Regular visits to your eye doctor are imperative to maintain a safe level of eye pressure.
Ex-PRESS Glaucoma Shunt
If medicated drops are insufficient at lowering your intraocular pressure (IOP), your doctor may suggest glaucoma filtration surgery. The Ex-PRESS glaucoma shunt is a newer procedure, and an alternative to a larger silicone tube shunt or a trabeculectomy. About the size of a grain of rice, the shunt is a simple method of filtration for open-angle glaucoma and lowers IOP by routing aqueous humor from the anterior chamber of the eye. The area of drainage is covered by the eyelid and is not visible. The Ex-PRESS shunt procedure is a variation of a trabeculectomy procedure in which the shunt device creates an opening that your body has more difficulty scarring. This leads to a lower failure rate.
The Ex-PRESS shunt takes effect immediately, and eye pressure should stabilize within the first four weeks. Studies have found fewer post-op complications in Ex-PRESS shunts compared to trabeculectomy, and patients experience a faster recovery of visual acuity.
What Happens During Shunt Surgery?
Ex-PRESS shunt surgery can be done under local or general anesthesia and takes about 45 minutes. After anesthesia is administered, your surgeon will use an injection system to implant the shunt. A metal rod is fitted into the lumen of the shunt and is attached to the end of an injector. Your surgeon will make a small flap in your sclera and angle the shunt into the opening. The injector is depressed and the metal rod is placed into the eye. Your surgeon will then suture the opening in the sclera and overlying conjunctiva.
What to Expect
Your surgeon will go over your medications and may advise you to stop taking certain prescriptions before the procedure. You will be given antibiotics, anti-inflammatory medications and sometimes laxatives to take after the surgery. Most people return to work anywhere from 2 to 7 days after the procedure. During the recovery period, you should avoid strenuous activities and sports as well as lifting, bending and straining.
Outcomes of Shunt Surgery
The mini shunt takes effect immediately, and eye pressure should stabilize within the first four weeks. The mini shunt often eliminates the need for glaucoma eye drops. Studies have found fewer post-op complications in mini shunts compared to trabeculectomy and patients experience a faster recovery of visual acuity.
Glaucoma Drainage Devices
If trabeculectomy is not effective or your eyes have extensive scarring from previous surgeries, your doctor may recommend a tube shunt procedure called a glaucoma drainage device (GDD). These devices are designed to route excess fluid from the anterior chamber of the eye to an exterior reservoir using a silicone tube. The GDD is a plate that is hidden under the upper eyelid and is attached to the anterior chamber of the eye using a small silicone tube that penetrates into the eye through a very small hole in the sclera. Although glaucoma drainage devices are extremely effective at controlling internal ocular pressure and have a low risk of surgical failure, many patients still use some drops to help control the pressure.
What Happens During GDD Surgery?
Your surgeon may take you off certain medications up to two weeks before surgery, especially blood thinners. Glaucoma drainage device surgery is typically done using light sedation in addition to medicine that anesthetizes the entire eye, with the entire procedure taking less than an hour. After your anesthesia has been administered, your surgeon will make a small incision in the conjunctiva to allow adequate exposure for the plate. The implant will be anchored between two rectus muscles and will be secured with sutures.
What to Expect
You may experience some redness or swelling after surgery, and your eyelid may droop a bit. This will go away after a few weeks. Often, you will be given a topical antibiotic and steroid to use four times daily for 4 to 6 weeks. Most patients take about a week or two off work, and during the recovery period you should avoid bending down and participating in any sports activities.
Outcomes of GDD Surgery
GDDs have proven to be extremely effective in controlling IOP and have a low risk of surgical failure. Sometimes, GDDs are preferred over trabeculectomy because there is a lower risk of infection and low eye pressure called hypotony. This surgical method is especially effective in patients whose IOP cannot be controlled with traditional surgery or who have previous scarring.
Contact one of our treatment centers to make an appointment to discuss a glaucoma treatment plan that is best for you.