Laser Trabeculoplasty for Glaucoma
A laser trabeculoplasty is a laser treatment used to reduce pressure in the eye (intraocular pressure). The goal of the procedure is to relieve intraocular pressure by stimulating the internal drainage system allowing adequate outflow of fluid (aqueous humor) from the eye.
There are two types of laser trabeculoplasty procedures: argon laser trabeculoplasty (ALT) and selective laser trabeculoplasty (SLT). The glaucoma specialists at the Dean McGee Eye Institute (DMEI) provide both of these laser techniques in-office in our laser rooms.
Who Is a Good Candidate for Laser Trabeculoplasty?
Laser trabeculoplasty procedures can be performed on those with ocular hypertension or open-angle glaucoma. Open angle glaucoma is a form of glaucoma in which the drainage angle between the iris (the colored part of your eye) and the cornea (the clear front window of your eye), called the trabecular meshwork, is open but does not allow fluid to drain adequately. Ocular hypertension is characterized by above-average pressure in the eye with an open drainage angle but without the presence of optic nerve damage.
Your doctor will determine if you are a good candidate for laser trabeculoplasty as well as which form of the treatment is the best option for you based on your unique situation.
What Is the Difference Between ALT and SLT?
Argon laser trabeculoplasty (ALT) is an older procedure in which a small laser beam is used to widen the drainage angle and open clogged channels in the trabecular meshwork. Half or all of one eye is treated in a single session with the other half treated in a follow-up session if necessary. This method may only be repeated once.
Selective laser trabeculoplasty (SLT) is a newer procedure that users a larger, gentler laser beam than ALT. During this procedure, pigmented cells are targeted selectively, leaving untreated portions of the trabecular meshwork intact. Unlike ALT, SLT can be repeated multiple times if the effect wears off over time.
Before the Procedure
Because laser trabeculoplasty is a non-incisional procedure, you may eat and drink as you like before the treatment. You should also continue to take all prescribed glaucoma medications as well as any other medications you take regularly.
When you arrive for the procedure, your vision and eye pressure will be checked, and eye drops will be administered to lower your eye pressure prior to the treatment.
You will be seated at the laser instrument and a drop of anesthetic will be placed in the eye to numb the area. A special lens that directs the laser energy to the eye’s drainage angle will then be placed on the eye, along with gel to enhance the view of the angle.
The laser will be used to place approximately 50 to 100 laser spots along one-half or all of the trabecular meshwork. The laser will not harm the remainder of the eye. You may feel slight tingling or stinging during the treatment and you will see bright flashes of light. Overall, the procedure is usually completed within 10 to 15 minutes.
Following the Procedure
The special lens will be removed, the eye rinsed, and additional eye drops administered to keep eye pressure down. You will be asked to sit in the waiting area for 30 minutes to an hour, at which time your doctor will check that your eye pressure has not risen as a result of the treatment.
If your doctor deems your eye pressure is satisfactory, you may be driven home by a friend or family member. If your eye pressure has increased, you may need to stay in the office for additional treatment and pressure measurements until the pressure comes down.
Are There Risks Associated with Laser Trabeculoplasty?
Your eye may be slightly irritated and your vision slightly blurry following the procedure, but these effects should be temporary. Typically, any increase in intraocular pressure following the procedure is also temporary and can be treated with medication. Rarely, the pressure increase can persist and, if dangerously high, may require urgent glaucoma surgery.
Other complications can include temporary inflammation of the eye (which can be treated with medication) or a scratch or irritation on the eye’s surface from the laser lens.
Even if the laser trabeculoplasty procedure works well to lower intraocular pressure, you may need to continue taking most, if not all, of the glaucoma medications you were previously prescribed on a long-term basis.
You will not be required to wear an eye patch, and you may continue your usual activities the same day of the procedure. Your doctor may prescribe anti-inflammatory eye drops that you will need to use temporarily following the procedure. You should also continue taking all previously prescribed glaucoma medications.
The laser trabeculoplasty procedure will take several weeks to take full effect.
Postoperative appointments will be scheduled for approximately one to two weeks and then one to two months following the procedure to assess the treatment’s effectiveness. During one of these appointments, your doctor may wish to perform the same laser treatment on the other half of the trabecular meshwork in the same eye or may treat your other eye.