Overview

A laser peripheral iridotomy is a treatment for angle closure glaucoma.

If you have healthy eyes, the fluid in your eye (aqueous humour) flows through your pupil into the front of your eye. The fluid then drains away through drainage channels called the trabecular meshwork.

However, if you have angle closure, these drainage channels are blocked by the iris (the coloured part of your eye). Because of this, the fluid cannot leave your eye, so your eye pressure (also known as intraocular pressure) increases. 

The build-up of pressure injures your optic nerve, which is the nerve that carries information from your eye to your brain. It also damages your vision.

During a laser peripheral iridotomy, we use a laser beam to create a small hole in your iris. This forms a permanent passage that allows the fluid in your eye to drain out. It may also change the position of the iris tissue, and unblocks the drainage channels. 

Aqueous humour is a completely different fluid to your tears. Your tears will not be affected by the procedure. 

Benefits of a laser peripheral iridotomy

The laser treatment prevents a sudden (acute) rise in pressure within your eye. Without this treatment, you are at risk of developing sudden glaucoma and irreversible blindness.

It's important to remember this procedure will not change your vision. It will not restore any sight you may already have lost, or improve your sight. 

Risks of a laser peripheral iridotomy

Complications after this treatment are uncommon. A small number of patients find that extra light enters through the new opening, which can be a little distracting at first. However, most patients find they are soon able to ignore this.

Rise in eye pressure after treatment

Occasionally your eye pressure will rise immediately after laser treatment. If this happens, you may need eye drops or tablets. 

We let you know which treatment you need and how long you need to take the treatment for. If we give you eye drops, a doctor or nurse puts them in your eye before you leave hospital. We ask you to stay in the department until your eye pressure has reduced to a satisfactory level. This should take a few hours at most.

Other risks and complications

Occasionally the laser beam opening is incomplete, or not big enough. This will be discovered either after your treatment, or on your follow-up visit. If this is the case, we will have to repeat the treatment at a later date.

Other complications are haemorrhage in the eye from the laser and inflammation. This is usually small and can be treated with having steroid drops more often.

Certain symptoms could mean that you need to be treated quickly.

Other treatment options 

An alternative to laser treatment is a cataract operation, which may not be suitable for everyone. It also has a greater risk of complications.

Some patients with this condition also develop a long-term (chronic) rise in their eye pressure. In this case, you may need drops or other treatments in the long-term to keep your eye pressure within safe limits.

Giving your permission (consent)

We want to involve you in decisions about your care and treatment. If you decide to have the procedure or treatment, we will ask you to sign a consent form. This says that you understand what is involved and agree to have the treatment.

Read more about our consent process.

Preparing for treatment

You can eat and drink as normal on the day of your treatment.

You must take your eye medicines as normal on the morning of the laser treatment, unless your doctor has told you not to. 

Having a laser peripheral iridotomy

You will be in the outpatient department for about half a day.

We do the treatment in one of our laser treatment rooms. You remain in your own clothes for the procedure.

The doctor or nurse assesses your eye first, and checks the pressure. We put some drops into your eye. These are usually:

• to make your pupil smaller
• to lower the intraocular pressure (the pressure inside your eye due to aqueous)
• an anaesthetic eye drop to numb your eye

You sit at the laser machine, which is similar to the machine that we use to examine your eye at the eye clinic.

The doctor puts a special contact lens on your eye before applying the laser beam. This lens lets the doctor view your iris clearly.

We use the laser to make a small hole in your iris. This takes about 20 minutes.

You will not feel any pain because the anaesthetic drop we put in your eye numbs it. However, you might feel slight discomfort when the laser is being used.

After the procedure, you return to the waiting area. About 1 hour later, we check the eye pressure. We also examine the eye to check the new opening is working well.

After the procedure

If you have discomfort once you get home, take your usual pain relief. Always follow the instructions on the packet. It's normal to have gritty, sticky eyelids and mild discomfort for a couple of hours after laser treatment.

The eye drops can also take some time to wear off, and you should not be alarmed if your pupils are still small for several hours after treatment.

The drops applied in clinic can also cause a mild to moderate headache across your brow. Because they make your pupil small, you might find that a dim or dark room is quite dark. Do not panic. The medicine will have worn off by the morning, and your pupils should be back to their normal size again.

You may also find that your vision is a little blurred. This is normal, and your vision should return to how it was before the laser by the end of the day.

After you leave hospital

We might prescribe anti-inflammatory drops after your laser treatment. These help to reduce inflammation (but not infection) in the eye. People normally only take these for 1 week. The doctor will tell you how long you need to take them for. You do not need antibiotics because your eye does not have an open wound.

If you are using glaucoma drops, please check with the nurse or the doctor whether or not you need to continue using them on your treated eye. It is usual to continue using them unless your doctor has said otherwise.

If you are using glaucoma drops to the untreated eye, please continue to use them unless clearly instructed otherwise.

You can do all of your daily activities as you would normally without any problems.

Follow-up appointments

We see you in the outpatient department 1 to 2 weeks later to make sure your eye has responded well to treatment. You have another check-up to see if the treatment was successful. You should be given a follow-up appointment before you leave the hospital after your treatment.