LASER PERIPHERAL IRIDOTOMY

LPI: A Laser Procedure for Narrow Angle and Closed Angle Glaucoma

What is angle closure glaucoma?

The drainage site is found within the “angle” where the iris (the colored part of the eye) and the cornea (the clear covering forming the front of the eye) meet.

Angle closure is when the natural flow of fluid inside the eye is blocked near the drainage site of the eye by the colored part of the eye (iris). This causes a buildup of fluid within the eye leading to high eye pressures, irreversible damage to the optic nerve and permanent vision loss.

In some patients, the eye pressure elevation may happen suddenly causing pain, red eye, blurred vision, nausea and rarely vomiting. This condition is called an acute angle closure attack.

How does LPI work?

A tiny opening is created in the iris (the colored part of the eye) to help widen the pathway to the drain of the eye. This greatly reduces the chance of the drainage pathway closing, which prevents rapidly increasing eye pressures, irreversible damage to the optic nerve and permanent loss of vision.

Who needs an LPI?

Those who have been told by their doctor they have a narrow angle or have early signs of  closed angle glaucoma.

What should I expect if I have an LPI?

Your treatment will happen in a specially equipped laser room in the clinic. Once you have been checked in, drops will be used to numb your eye and check the pressure. No injections or needles will be used.

Then, you will receive some drops in your eye. The first drop is called pilocarpine and is used to make your pupil smaller. This stretches and thins your iris, which makes it easier for the laser to make a tiny hole. Some patients develop a mild headache after receiving this medication. The second drop is called apraclonidine. It is used to prevent bleeding and a rise in the eye pressure after the procedure.

Next, your doctor will place a special lens on your eye to help focus the laser on the iris. This lens also prevents your eye from blinking and keeps the eye still during the treatment.

A clear gel is placed between the eye and the lens to protect the surface of your eye. This gel may remain on your eye for up to an hour, leading to blurred vision or a feeling of heaviness.

While this laser is usually performed using one laser machine, sometimes your doctor may choose to use two laser machines to perform the LPI. If you are determined to have an especially thick iris the second machine is sometimes necessary to help create the opening. The laser treatment will take approximately 5 minutes to complete per eye.

During the laser treatment, you may see a bright light, like a photographer's flash from a close distance. Patients describe a range of sensations from feeling nothing, a pinch, or a static, shock-like zap to feeling similar to a snap of a rubber band on skin. Generally, the sensation is brief.

As a safety measure, your eye pressure will be checked after your procedure.

How often will I be seen after the laser procedure?
You will see your doctor about 2 weeks after the laser for the first visit and your physicians will tell you about your next visits.

What eye drops will I use after the laser procedure?
Steroid drops will be prescribed to alleviate any soreness or inflammation inside your eye.

Can I stop my glaucoma drops after the laser procedure?
Your doctor will tell you which drops to continue using and how often after the laser procedure.

Will my vision improve after the laser procedure?
This laser will not improve your vision.

What is the recovery time and what should I expect?
Though everyone heals differently, most people can resume normal activities right after treatment, although you'll need to have someone drive you home. For the next few days your eyes may be red, a little scratchy and sensitive to light if you develop inflammation in the eye after the procedure.

• If there is any blurred vision, it usually improves within hours or a day.
• There are no restrictions in reading, watching TV, using your phone, tablet device, computer, etc. but you may tire more easily during these activities.
• Tylenol (acetaminophen) is a good option if you feel any pain or discomfort unless you are unable to take this medication.
• If your eye has severe pain or sudden worsening pain or vision after surgery, please call our office or on call physician immediately.

Will LPI cure my glaucoma in those who have glaucoma?
The simple answer is “No”. Glaucoma is a chronic disease that requires constant monitoring and treatment. The LPI procedure may help to lower your eye pressure and widen the drainage angle. However, it will not reverse any loss of vision that has already occurred.

What are the risks of LPI?
Although LPI is very safe, there are no medical procedures with zero risk. Serious complications such as losing vision are extremely rare. The main risk of an LPI is that your iris may be difficult to penetrate, requiring more than one treatment session. Rarely, the laser spot in your iris may close requiring another procedure to open it again. Glare or visual disturbance, although uncommon, can occur in some patients. Symptoms often decrease with time and rarely require intervention. Lastly, the pressure in the eye may increase shortly after the laser. This typically can be controlled with pressure lowering eye drops and goes away on its own. It is extremely rare needing a surgery to lower the elevated eye pressure after LPI.

For more information, please see:
American Academy of Ophthalmology Patient Information Website

American Glaucoma Society Patient Information Website