YAG Eye Laser Peripheral Iridotomy

YAG Laser peripheral iridotomy is the standard first line treatment in closed angle glaucoma and eyes that are at risk of developing this condition. This procedure helps to treat or prevent angle-closure glaucoma.

YAG Laser peripheral iridotomy is the standard first line treatment in closed angle glaucoma and eyes that are at risk of developing this condition. This procedure helps to treat or prevent angle-closure glaucoma.

What does YAG Laser Peripheral Iridotomy stand for?Yttrium Aluminium Garnet (YAG). This is a synthetic gemstone used to create the specific wavelength of light for the laser procedure.  The YAG laser is a powerful beam of light used to make small holes into the iris (iridotomy) the coloured part of the eye. This is generally done in the far edge (periphery) of the top part of the iris that is hidden under the upper eye lid. The fluid inside your eye can then circulate more freely through this small hole. This helps to control the eye pressure. The laser peripheral iridotomy procedure has been used since 1984 both as a treatment and prevention of the glaucoma. If performed early in patients with narrow angles, the chance of successfully preventing angle-closure is up to 75%. In more advanced cases medications and/or surgery may also be required.


Why do I need a YAG Laser Peripheral Iridotomy?

Normally the fluid (aqueous humour) in the front of the eye is constantly flowing from where it is formed (the ciliary body) to the front of the eye. This fluid nourishes your eye and helps to keep its shape. The angle is the area between the iris (coloured part of the eye) and the cornea (the clear outer layer on the front of the eye). Fluid drains out through the angle into drainage channels (trabecular meshwork) and is then reabsorbed by the body.  When fluid flows out too slowly, eye pressure builds up. “Angle-closure” describes critical narrowing of the eye’s drainage angle, causing the eye pressure to quickly rise to very high levels. This can rapidly damage the optic nerves and may cause a type of irreversible sight loss known as glaucoma. If the drainage of fluid is blocked for any reason, the pressure in the eye increases.

Your ophthalmologist uses a special mirrored lens called gonioscopy to examine the drainage system of your eye. When the angle is narrow, your ophthalmologist can only see portions of the drainage angle, and in acute angle-closure glaucoma, none of the drainage angle is visible.

You may have narrow angles due to having a shorter eye than the average person, being hyperopic (far-sighted) or having a growing cataract that gradually narrows the angle over time. You may also have a closed angle because of inflammatory conditions such as uveitis, or vascular conditions, such as diabetes, that gradually cause what is termed “secondary angle closure” over time.

The YAG laser Peripheral Irodotomy is a procedure performed to save the sight you still have. It will not restore any sight you may have already lost, nor will it improve your sight. The laser treatment is to prevent a sudden (acute) rise in pressure within your eye. Without having this treatment, you are at risk of developing sudden glaucoma and irreversible blindness.


What is acute angle-closure glaucoma?

If you are a primary angle-closure “suspect” you could be at risk for a potentially very serious condition called acute angle-closure glaucoma.

Acute angle-closure attacks often take place when the pupil dilates e.g. at night or in a dark movie theatre. When the pupil dilates the drainage structures can become partially obstructed in someone with narrow angles. The pressure may slowly build up in the back part of the eye and cause the iris to push forward and the angle to narrow even further, eventually blocking off most or all of the drainage of fluid from the eye. When this happens the eye pressure increases dramatically. Imagine a basketball that is continually being pumped up and the pressure that is building up inside it. The cornea may become cloudy due to the increased pressure, the eye may become red and your vision will decrease. The increased eye pressure is painful and sometimes leads to nausea and vomiting. If left untreated there is irreversible damage to the optic nerve, the part of the eye that transmits light and visual information to the brain. The treatment is to lower eye pressure using eye drops and sometimes oral medications but the best treatment at the time of the glaucoma attack is to have a YAG laser peripheral iridotomy and sometimes this is done as an emergency procedure.

Can anatomically narrow angles be treated?

Yes, a laser beam (the YAG laser) is used to make a microscopic hole in the outer edge of the iris (the coloured part of the eye) to allow the iris to fall away from the drainage area inside the eye, leading to an opening of the angle to allow the aqueous humour to flow. The hole (iridotomy) is like a “release valve” creating an alternate channel for the fluid to flow through the eye allowing the pressure in the front of the eye to equalise with the pressure in the back of the eye.

What is angle-closure “suspects”?

Laser peripheral iridotomy is the same procedure used to preventively treat primary angle-closure suspects, or patients with narrow angles that are at risk for an angle-closure attack. Although not all patients with narrow angles go on to develop angle-closure glaucoma, laser iridotomy is often performed as a preventive measure because it is relatively low risk compared to potential serious consequences of angle-closure glaucoma. There is a small risk (1-2% a year) that those people with anatomically narrow angles will develop angle closure. Once angle closure develops it can be difficult to treat. There is also the chance that the angle will close slowly and cause scarring, and slowly increase pressure in the eye. There is often no pain with chronic angle closure, and you can loose vision without being aware that your eye pressure is high.

What happens during a YAG Laser Peripheral Iridotomy?

The procedure can be done in the Bowen Eye Clinic purpose build laser room.

Bring your glasses with you so that we can check your vision.

You do not need any special preparations and can eat and drink as normal.

The surgeon will asses your eye first and check the pressure. It is important that you use your regular eye medication drops as normal on the morning of your laser treatment (unless your surgeon has told you not too).

You will then have some drops put into your eye to make your pupil smaller and a drop to lower the intra-ocular pressure (the pressure inside your eye due to the aquaous humour fluid), and an anaesthetic drop to numb your eye.

You will then sit at a machine similar to the machine that was used to examine your eyes. This machine has the YAG laser attached to it.

The surgeon will put a special contact lens on your eye before applying the laser beam. This lens allows the surgeon to view your iris clearly so they can apply the laser and make the hole in your iris.

You will feel no pain due to the anaesthetic drop used to numb your eye before the laser, but you might feel a slight discomfort when the laser is applied.

The procedure only takes about 10 minutes but you will be at the clinic for 30 minutes.

You will be able to go home after the laser procedure with a prescription for eyedrops.

What shall I expect after a YAG Laser Peripheral Iridotomy?

You may have a slight headache above your eye from the eye drops which make your pupil smaller. This is temporary and will go.

Please arrange for someone to take you home as you will not be able to drive. Rest for the remainder of the day.

There are no restrictions after surgery and you can resume normal activities.

What are the risks of having a YAG Laser Peripheral Iridotomy?

The laser treatment is considered safe but as with any procedure there is an element of risk which includes:

brief blurred vision (common)

inflammation - which should settle with the drops given after treatment

minor bleeding inside your eye

temporary increase of pressure in the eye

closure of the new opening in which case a repeat YAG laser may be needed

worsening of the clouding of the lens (cataract) that was present before laser treatment

glare from light entering through the new opening (rare)

retinal tear and detachment (very rare)

Will the YAG Laser Peripheral Iridotomy improve my vision?

The laser will not improve your vision. YAG laser iridotomy is intended to preserve the vision that you have and prevent glaucoma from appearing or progressing. There remains a risk of developing glaucoma in the future and you should continue to have eye check-ups with your optician / ophthalmologist.

Will I still need to use my glaucoma medications?

Yes, laser iridotomy is not a substitute for glaucoma eye drops. In most cases if the patient is already on medication prior to the procedure these will need to be continued.

What happens if it doesn’t work?

There are no other alternatives to open up the drainage channels in your eye. In about 10% of cases the angle may not open. Some patients may require further laser procedures, medical treatment or other surgery such as cataract surgery or glaucoma filtering surgery. Your ophthalmologist will discuss all treatment options with you.

How long does it last?

A YAG peripheral iridomtomy is normally a permanent change. Although the angle widens in most cases after YAG laser, normal age-related changes can still occur and may subsequently alter the angle region. A cataract may form and close the angle again and cataract surgery may be required.

To learn more about the YAG Laser Peripheral Iridotomy procedure and if you are a suitable candidate please contact Bowen Eye Clinic on 0800 69 2020 for an appointment.