How is YAG laser applied?

In one of our latest articles, Mr Sameer Trikha, a highly revered and skilled London-based consultant ophthalmologist, details when a YAG laser can be most effectively used, and explains how exactly the laser is applied.

What is the purpose of YAG laser?

A YAG laser can be used in a variety of different ways within the field of ophthalmology. Most commonly, YAG laser is used for three main conditions. These include:

• posterior capsule opacification
• primary open angle glaucoma or ocular hypertension
• narrow or closed drainage angles

The first condition is where there is a build-up of material behind the artificial lens implant when patients undergo cataract surgery. This is often termed capsule opacification, and because it’s behind the lens implant, is it named posterior capsule opacification, or PCO for short.

As this material is cloudy, it can cause cloudy vision in patients. A YAG laser is used to apply energy to remove the mistiness and clear it out of the way from the artificial lens. In doing so, the vision will be improved. This procedure is called a YAG capsulotomy, and is quick and painless, often only taking a few minutes. Occasionally, patients can experience floaters after the procedure, but these often settle after a short time.

The second group of conditions that a type of YAG laser can be used for is open-angle glaucoma or ocular hypertension (where a patient may have raised pressure in the eye but no signs of glaucoma damage). In this instance, a surgeon can apply the laser to a lining in the front chamber of the eye, called the trabecular meshwork, that usually drains away the aqueous fluid. By applying the laser here, this opens up the lining and makes it more porous, thereby reducing the pressure within the eye. 

This is now being used as a first-line treatment for patients who are newly diagnosed with open-angle glaucoma or ocular hypertension. Similarly, it is also being used in patients who have high eye pressure and who want to avoid eyedrops on a regular basis.

Occasionally, some patients may have an anatomical variant within the eyes, whereby access to the trabecular meshwork is narrow, or in some instances, blocked off. As a consequence, the aqueous fluid has no way of draining from the eye and the pressure in the eye can build up. This is known as acute primary angle closure.

A YAG laser can be applied, using a special lens, to the iris which is the coloured structure of the eye. By creating a tiny, microscopic hole in the iris, close to the trabecular meshwork, this opens up the drainage angle and allows more aqueous to flow to the trabecular meshwork. In turn, this reduces the risk of the drainage angle closing off.

Can YAG laser treat other eye problems as well?

YAG laser can occasionally be used to treat other eye problems, but is primarily used for the conditions mentioned above.

How is YAG laser applied?

Essentially, the patient leans forward in front of a machine and rests their chin on the rest. The surgeon applies the laser through a contact lens that is touching the patient’s eye. We use local anaesthetic first to make sure the patient doesn’t feel anything. Then, we apply the contact lens onto the eye to give us a very controlled way of applying the laser to the desired structure within the eye. We do not fire the laser unless we have a direct view of the structure we need to laser.

Can YAG laser damage the lens implant?

The short answer is yes, it can. Therefore, it is very important to choose an experienced surgeon. Generally, when lens damage occurs, this does not normally affect the vision in the eye.

What are the medical and patient benefits of YAG laser over other treatments?

YAG laser treatments are usually very beneficial when improving patients’ vision, or helping to reduce the pressure in the eye. Other benefits include not needing eyedrops, and the avoidance of side effects when eyedrops are used.

What are the side effects of YAG laser? Will patients experience blurry vision?

With YAG laser capsulotomy, patients do sometimes experience blurry vision for the first 24 hours after the procedure. Occasionally, patients can experience floaters in the vision, but they normally settle quickly. Inflammation may also be experienced, which can cause aching in the eyes and sensitivity to light. Very occasionally, with SLT laser, one in 100 patients may experience raised eye pressure, but can be treated effectively with drops. For YAG laser peripheral iridotomy, patients can experience minor inflammation and in very rare circumstances glare or ghosting of images.

When would a repeat YAG laser be considered?

Occasionally, we can repeat the SLT procedure when treating open-angle glaucoma when the effect of the initial laser treatment wears off. This can happen In a small proportion of patients after a period of two or three years. The benefit of this laser procedure is that it can be repeated with ease and can be as equally effective the second time round when it comes to reducing pressure in the eyes.

Make sure you check out Mr Sameer Trikha’s Top Doctors profile today to book an appointment with him, especially if you are considering YAG laser treatment in the near future.