Updated on  February 21, 2024
5 min read

What is Laser Trabeculoplasty?

6 sources cited
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Laser trabeculoplasty is a surgical procedure that treats open-angle glaucoma by lowering intraocular pressure. 

Trabeculoplasty being performed by the eye doctor to a female patient

Glaucoma is a series of eye conditions caused by increased intraocular pressure (ocular hypertension). It permanently damages the optic nerve (the communication pathway between the eye and brain), leading to vision loss and blindness. 

Open-angle glaucoma, the most common type, occurs when the eye’s drainage angle (drainage system) is clogged. This results in a backup of aqueous humor (the clear fluid that gives eyes shape and nutrients), increasing eye pressure and damaging the optic nerve over time. 

Laser trabeculoplasty uses a laser to target the trabecular meshwork, a structure in the drainage angle. This allows eye fluid to flow normally and reduces intraocular pressure.

Who is a Candidate for Laser Trabeculoplasty?

Candidates for selective laser trabeculoplasty include people in need of treatment to lower intraocular pressure due to:

  • Primary open-angle glaucoma
  • Secondary open-angle glaucoma

Laser trabeculoplasty is recommended when glaucoma medications alone do not lower intraocular pressure. 

Selective laser trabeculoplasty may also be recommended as a first-line treatment for people who can’t tolerate or afford daily medicated glaucoma drops.

Laser Trabeculoplasty Procedure

Laser trabeculoplasty is an outpatient procedure performed in an ophthalmologist’s office. The laser treatment takes 10 to 15 minutes and involves minimal pain.

Selective laser trabeculoplasty uses laser energy to target the trabecular meshwork (drainage tissue). This action opens up the trabecular meshwork, allowing for better drainage and lowering eye pressure. 

Before Surgery

To prepare for a laser trabeculoplasty procedure, you should:

  • Eat a good breakfast and take your glaucoma medication as prescribed
  • Plan to be at the doctor’s office or clinic for several hours (you may want to bring a book or other entertainment)
  • Wear comfortable clothing
  • Avoid wearing makeup
  • Bring dark glasses for the drive home

During Surgery

Before the procedure, the doctor will take an intraocular pressure measurement. They will administer medicated eye drops to lower eye pressure and numb your eye. 

During the laser surgery, you will sit in a comfortable position, and the doctor will:

  • Place a mirrored contact lens over your iris to guide the laser
  • Use a slit lamp microscope to focus on the treatment area
  • Administer a series of 50 to 100 laser applications, which may result in a clicking sound

The entire procedure lasts about 10 to 15 minutes.

After Surgery

The doctor will check your intraocular pressure about 45 minutes to 1 hour after surgery. If it is within a normal range, you can go home. 

After surgery, you:

  • Must schedule a follow-up appointment a week after the procedure
  • Will need to administer anti-inflammatory eye drops daily for 3 to 7 days
  • May experience blurry vision, which should clear up the next day
  • May experience mild discomfort and soreness for a few days

It takes about 6 weeks to see results from laser trabeculoplasty. After 6 weeks, you will make another appointment to recheck eye pressure and see if the procedure was successful. 

Repeat Treatment

The effects of selective laser trabeculoplasty tend to wear off 1 to 5 years after treatment. Because SLT uses minimal heat, you can repeat the procedure as needed.

However, repeat treatments might not lower eye pressure as much as the first laser trabeculoplasty procedure.

Different Types of Laser Trabeculoplasty

There are three types of laser trabeculoplasty:

  1. Selective laser trabeculoplasty (SLT). Uses a YAG laser, producing minimal heat and less scar tissue than other lasers. 
  2. Argon laser trabeculoplasty (ALT). Uses a thermal heat laser to target the tissue. 
  3. Micropulse laser trabeculoplasty (MLT). Uses pulsing energy to target the tissue. 

Selective laser trabeculoplasty is the most popular form due to less tissue scarring. It can also be repeated as needed.

Side Effects of Laser Trabeculoplasty

Side effects of laser trabeculoplasty are generally mild and include:

  • Soreness
  • Discomfort
  • Redness
  • Blurred vision 
  • Light sensitivity

What are the Risks?

Complications from laser trabeculoplasty are rare. The most significant risks after the procedure include:

  • Elevated eye pressure
  • Swelling and post-operative inflammation in the treated eye
  • Peripheral anterior synechiae (iris sticks to the cornea)

Elevated eye pressure and inflammation are usually temporary and can be treated with glaucoma medication and anti-inflammatory eye drops. However, peripheral anterior synechiae can cause complications that may require surgery.

Contact your eye doctor immediately if you experience severe pain or changes in vision after the procedure.

Trabeculoplasty Outlook and Success Rates

Selective laser trabeculoplasty is both safe and effective at lowering eye pressure. It effectively lowers eye pressure by 20% for 60 to 70% of people who get the procedure.1 

However, laser trabeculoplasty does not work for everyone and is not a cure for glaucoma. Effects of the initial treatment typically last 1 to 5 years. Repeat treatments are needed after that.

Some people attain normal intraocular pressure with just laser treatment. Others may need laser therapy plus one or more glaucoma medications.

Alternative Treatments for Glaucoma

If you’re not a candidate for selective laser trabeculoplasty, your doctor may recommend one or more of the following: 


Various prescription eye drop medications treat glaucoma by lowering intraocular pressure. These include:

  • Beta-blockers
  • Alpha agonists
  • Prostaglandin analogs
  • Carbonic anhydrase inhibitors
  • Rho kinase inhibitors

New types of drugs to treat glaucoma are being investigated. Some people need to continue taking glaucoma medications even after laser treatment. 

Laser Treatment

Selective laser trabeculoplasty isn’t the only laser procedure available. Alternative laser treatments include:

  • Argon laser trabeculoplasty (ALT). Uses a thermal heat laser to target the tissue. 
  • Micropulse laser trabeculoplasty (MLT). Uses pulsing laser energy to target the tissue. 
  • Laser iridotomy. Uses a laser beam to make a small hole in the iris.


Trabeculectomy may be required if laser procedures and medications aren’t effective. This type of glaucoma surgery involves creating a new channel for eye fluid to flow. 

The surgeon will cut a small flap in the white of the eye (sclera) beneath the upper eyelid. They create a new fluid drainage channel beneath the flap. They cover the flap with conjunctival tissue (the clear membrane covering the eye). 

Fluid drains through the new channel and creates a blister (bleb) in the membrane under the eyelid. The body reabsorbs the fluid, and the eye pressure remains normal.


Laser trabeculoplasty is a safe and effective way to lower eye pressure for people with glaucoma. The procedure uses a laser beam to target drainage tissue, allowing eye fluid to flow normally and stabilizing eye pressure.

The laser treatment takes place in an eye doctor’s office and takes 10 to 15 minutes. You can resume normal activities afterward. 

You’ll see results in about 6 weeks. The effects wear off in 1 to 5 years.

Updated on  February 21, 2024
6 sources cited
Updated on  February 21, 2024
  1. Ou, Y. “Laser procedures for glaucoma.” BrightFocus Foundation, 2021. 

  2. Ang, et al. “Selective laser trabeculoplasty as the primary treatment for open angle glaucoma: time for change?” Eye, 2019.

  3. Laser Trabeculoplasty.” Glaucoma Institute of Northern New Jersey, n.d. 

  4. Selective Laser Trabeculoplasty.” University of Michigan Kellogg Eye Center, 2014.

  5. Treating Glaucoma.” Glaucoma Research Foundation, n.d.

  6. Shaw, E. and Gupta, P. “Laser Trabeculoplasty.” StatPearls, 2023.

The information provided on VisionCenter.org should not be used in place of actual information provided by a doctor or a specialist.