What is laser peripheral iridotomy (LPI)?
Laser peripheral iridotomy is a procedure to prevent or treat narrow-angle glaucoma, also called angle-closure glaucoma. It uses a laser to make a tiny hole in the iris, the colored part of the eye. This can help fluid in the eye drain better and lower eye pressure to reduce the risk of vision loss.
LPI is often the first-line treatment for closed-angle glaucoma and for people who have narrow angles and are at risk for the condition. Eye doctors have been using this laser treatment since 1984. The procedure can usually be performed in the doctor's office.
The laser treatment helps keep eye pressure in the normal range and protects vision from glaucoma damage. This treatment is effective for about two-thirds of people if performed at earlier stages of the disease. It may also help slow the disease in later stages. People with advanced glaucoma might need medicine or surgery along with laser treatment to control their condition.
It’s important to be aware that LPI is performed to preserve your vision and prevent glaucoma from progressing or causing sudden attacks; it is not intended to improve eyesight.
Why you might need LPI
Laser peripheral iridotomy is commonly used to treat narrow-angle glaucoma. This condition occurs when there is a narrowing of the angle at which the iris and cornea (the clear, dome-shaped layer at the front of the eye) meet. This is where a nourishing fluid called aqueous humor drains.
If this angle gets too narrow, it is hard for the fluid to leave the eye. This can cause the pressure inside your eye to go up. If this high pressure is not treated, it can damage the optic nerve that connects the eye to the brain. Injury to this nerve can lead to permanent vision loss. Although angle-closure glaucoma is not as common as other types like open-angle glaucoma, it can be more serious and needs prompt medical attention.
Factors that can increase the risk of narrow angles include:
- Having a family history of angle-closure glaucoma
- Being over age 60
- Being female
- Having smaller eyes
Narrow-angle glaucoma requires a different surgery than open-angle glaucoma. If you have narrow angles, the tiny holes made in the iris by the laser during LPI can help the fluid drain better. Laser peripheral iridotomy is typically recommended for patients with:
- Acute primary angle closure (APAC) – This is a serious eye condition caused by a sudden blockage of the eye's drainage system. An acute attack usually involves very high pressure in your eye, pain and blurry vision. If you have an acute attack of angle closure glaucoma, LPI is used to help lower the pressure in your eye. It also helps to prevent you from having another attack in the future.
- Primary angle closure glaucoma (PACG) – This is chronic narrow-angle glaucoma. A chronic decrease in fluid outflow causes high pressure in the eyes. LPI can help bring the pressure down.
- Primary angle closure suspect (PACS) – This is when you have narrow angles that put you at a higher risk of having a sudden APAC attack. The LPI procedure is performed as a preventative step.
READ MORE: Narrow-angle glaucoma (angle-closure glaucoma)
How the laser peripheral iridotomy procedure works
Laser peripheral iridotomy is a procedure in which a laser is used to make a very small opening in the colored part of the eye. The most common type of laser that is used is a YAG laser. The openings help the fluid inside your eye drain properly when the normal drainage area (called the angle) is narrow or blocked. This helps to lower the eye pressure and reduce the risk of damage to the optic nerve and potential vision loss.
Before the LPI procedure
The LPI procedure will usually take place in your doctor’s office. This procedure does not require needles or injections. Getting ready for the actual laser treatment usually takes about 30 minutes.
During this period:
- Numbing drops will be placed in your eye so you won't feel pain during the procedure.
- Eye drops will also be placed in your eye to make your pupil smaller. This helps stretch the iris, making it easier for the laser to create a small hole.
- The staff may check your eye pressure before the laser treatment.
- Other eye drops may be given to help prevent a rise in eye pressure or bleeding after the procedure.
- You'll be asked to sit in front of the instrument used for the procedure, which looks similar to the one your eye doctor uses during regular eye exams.
During the procedure
The procedure itself is usually quite quick, typically taking only about five to 10 minutes per eye.
During the procedure:
- Your doctor will place a special contact lens on your eye. This lens helps to focus the laser beam precisely onto your iris. It also helps to keep your eye from moving and prevents blinking during the treatment.
- The laser will then be used to deliver several quick bursts of light to create the tiny hole in your iris. Most people don't feel much during the laser treatment. Some might describe a brief sensation like a small pinch or tap in the eye.
- You might see bright flashes of light or hear a soft clicking noise from the laser. The doctor will confirm that the hole is properly created when they see a small release of pigment.
After the procedure
Soon after the LPI, your eye pressure will be checked again, usually within 30 minutes to one hour following the procedure. This is to make sure that the pressure hasn't gone up too high as a temporary side effect of the laser.
It's common to experience blurry vision right after the laser treatment due to the numbing drops and the gel used with the contact lens. Most people can resume their normal activities shortly after the procedure, although you might need someone to drive you home because of the temporary blurry vision.
You might also have some mild soreness, redness or a scratchy feeling for a day or two. Your doctor will likely prescribe anti-inflammatory eye drops (steroid drops) to use for a few days to a week. These will help reduce any inflammation inside the eye and promote healing.
It's important to follow your doctor's instructions for using the eye drops. Attend any follow-up appointments — usually at two weeks — to ensure everything is healing well.
READ MORE: Argon laser trabeculoplasty (ALT)
What LPI costs
Laser peripheral iridotomy cost can range from $1,000 to $2,000 or more without insurance. You can contact your eye doctor's office or the facility where the LPI will be performed to inquire about the exact cost of the procedure. They can provide you with the most accurate information regarding their fees.
You should also contact your health insurance provider to understand your potential out-of-pocket expenses. They will be able to explain your specific plan's coverage for LPI, especially if it is recommended due to a risk or diagnosis of glaucoma. They can also detail any co-pays, deductibles or other costs you might be responsible for.
Does LPI work?
LPI is a common, and often successful, first-line treatment. It is performed to treat and prevent sudden vision loss from narrow-angle glaucoma. For many people, this procedure effectively improves the ability of fluid to drain out of the eye. This helps keep the eyes safer from sudden glaucoma attacks.
Studies suggest that performing LPI early in the disease offers a 66%–75% chance of fixing the condition. However, it's important to understand that while LPI is often very helpful, it may not provide complete pressure reduction for everyone. Some individuals might still have high eye pressure or progression of glaucoma.
In these cases, additional treatments, such as eye drops and other procedures, might be necessary to further manage eye pressure and prevent vision loss.
Risks and side effects
After undergoing an LPI procedure, there are some side effects that you may experience as your eye heals.
Common
Many people notice redness in the eye, increased sensitivity to light or blurry vision for a few hours to a day or two. You might also feel a mild discomfort or a scratchy sensation in your eye. Sometimes, the eye drops used before the procedure to make your pupil smaller can cause a temporary headache. These side effects are usually mild and don't last long.
Shortly after the laser treatment, a temporary rise in the pressure inside your eye can also occur. This is usually monitored closely. If the pressure increases, your doctor will give you extra eye drops or medication to bring it back down.
There is also a slight chance of some bleeding from the tiny hole made in the iris. This bleeding is usually minor and clears up within a day or two. Inflammation inside the eye can also occur. Your doctor can prescribe steroid eye drops to help reduce it.
Rare
Some people experience vision side effects after LPI. These include seeing glare or halos around lights or noticing extra images ("ghosting") or shadows. These are thought to be due to light passing through the new opening in the iris.
In rare cases, the small hole created by the laser can narrow or close up, requiring another laser treatment to reopen it. There is also a very small risk that the laser procedure could contribute to the progression of cataracts in the future.
Tips for after LPI
Your vision may be blurry for several hours after the laser treatment. Arrange to have someone drive you home on the day of the procedure.
After your LPI procedure, follow your doctor's instructions to make sure your eye heals properly and the surgery works as it should. Use anti-inflammatory drops as directed to help reduce swelling inside your eye.
Make sure to go to all of your scheduled follow-up appointments. These visits allow your doctor to check the pressure inside your eye and monitor how well the laser treatment is working.
If you experience any severe pain, a sudden worsening of pain or a decrease in your vision after the procedure, contact your doctor's office immediately.
READ MORE: Ocular hypertension: 5 Causes of high eye pressure
Ask your doctor about LPI
Your eye doctor may recommend LPI because you have narrow angles or could be at risk for angle-closure glaucoma. This procedure is quick and considered safe. It can save your sight by preventing sudden and serious vision loss from glaucoma.
Your doctor can discuss any concerns you may have, such as what to expect, risks and costs. Being well-informed about LPI can help you understand how this procedure can protect your vision.
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