Selective laser trabeculoplasty

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What is selective laser trabeculoplasty?

Selective laser trabeculoplasty (SLT) is an eye procedure performed in an office setting to lower the eye pressure in patients with certain types of open angle glaucoma or in patients with ocular hypertension. If left untreated, glaucoma can lead to permanent loss of the outer field of vision, and rarely the central vision.  

What is glaucoma?

The eye has a nerve, the optic nerve, that sends visual information to the brain. In glaucoma, the eye pressure (IOP) can build and result in damage to the optic nerve. The most common type of glaucoma is called open angle glaucoma where the eye pressure is high despite the drainage pathway (the angle) being open. In normal tension glaucoma, a less common type of open angle glaucoma, the optic nerve is sensitive to eye pressures in the normal range, resulting in glaucoma damage.  In all types of glaucoma the goal of treatment is to lower the eye pressure to a safe range.

healthy optic nerve
Optic nerve in glaucoma: the neuroretinal rim is thin because of nerve loss

How do I know if I have glaucoma?

Most patients will not realize their IOP is high, and can silently lose their peripheral vision from damage the pressure creates on the optic nerve.  Glaucoma risk is identified through screening eye examinations with your eye doctor, where the eye pressure, the optic nerve health, and your outer field of vision are assessed.

How is glaucoma managed?

Lowering eye pressure is the best way to manage glaucoma and prevent further optic nerve damage. Treatments to lower the eye pressure include daily eye drops, SLT laser, and glaucoma surgery. Your eye doctor will help you determine which treatment option is best for you. 

Will selective laser trabeculoplasty cure glaucoma?

There is no cure for glaucoma. Treatments, including SLT, lower the eye pressure to control the disease and reduce the risk of glaucoma progression. Patients with glaucoma require regular observation with specialized testing to ensure their glaucoma is stable and under control.   SLT laser can effectively lower the eye pressure and usually lasts around 3 to 5 years.  It can be repeated in future if needed.

What is the selective laser trabeculoplasty procedure?

SLT is performed by an ophthalmologist in an office or outpatient setting without any sedation. You will be given drops to constrict the pupil that can often cause a temporary headache above the brow. Anesthetic drops are used to make the eye comfortable and a specialized contact lens is placed on the eye to focus the laser.  Your eye surgeon will target the laser on the drainage pathway in your eye to help improve the outflow of fluid. It is normal for you to feel mild pain for a few minutes as the laser energy is applied.   Your eye pressure will be checked after the procedure to ensure it remains in a safe range.

SLT is a frequency-doubled (532nm) Q-switched Nd-Yag laser with a fixed spot size of 400um to target the trabecular meshwork drainage pathway

Risks of laser trabeculoplasty

Laser trabeculoplasty is a commonly performed procedure and complications are rare but may include:

  • Headache above the brow
  • Sudden increase in eye pressure
  • Inflammation in the eye
  • Laser does not effectively lower your eye pressure

What should I expect after the procedure?

Your vision may be blurry for a few hours after the laser and you may have mild light sensitivity, redness, or mild irritation for a few days. You should plan to have someone drive you home after the laser procedure. You can resume normal activities immediately afterwards. 

Cataract surgery wait times

Wait times for cataract surgery are updated monthly, with wait 1 representing how long it takes in days to get in to see the surgeon in the office, and wait 2, how long it takes after that to get in for surgery.
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