El SLT laser o Selective Laser Trabeculoplasty is a treatment that is performed in the ophthalmology office, in one session, lasts a few minutes, and does not present risks. This treatment is very effective in certain cases of glaucoma, where it is possible decrease the Intraocular pressure up to 30%.

En Área Oftalmológica Avanzada We give you all the information you need about it SLT laser.

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What is the SLT laser?

La Selective Laser Trabeculoplasty (SLT) is a safe and effective glaucoma laser treatment. It is presented as an alternative to the treatment of glaucoma in patients with ocular hypertension o open angle glaucoma primary or secondary, who have difficulties with the usual treatment (such as intolerance or lack of blood pressure control).

Through the use of the SLT laser, there is a controlled and intermittent heating of the pigmented cells of the trabecular meshwork, effect known as selective thermolysis.

It is a mechanism that allows to regulate intraocular pressure, but in a less invasive and traumatic that glaucoma surgery such as trabeculectomy or non-perforating deep sclerectomy, which we perform in the operating room and which, although they are very safe, are not exempt from the usual risks of an operating room.

This treatment is defined as selective since it acts selecting the pigment cells of the trabecular meshwork, responsible for regulating intraocular pressure and without causing any damage to the rest of the tissues.

What is this laser treatment for?

The SLT laser is used in those patients where eye drops are not able to sufficiently reduce the eye pressure, or they cause significant side effects. In the cases of glaucoma, can also be used as an initial treatment.

The studies carried out in relation to this topic indicate a 20% to 30% drop in intraocular pressure in 70% of patients, with a single 360º trabecular session. In 30% of cases, a re-treatment is needed after 5 years.

How does Selective Laser Trabeculoplasty work?

It should be noted that the SLT laser activates a tissue remodeling process, without producing thermal damage. Reason why can be repeated whenever needed, and it does not influence other possible glaucoma treatments that the patient may need in the future.

El process of the operation Selective laser trabeculoplasty is as follows:


Treatment preparation consists of application of a miotic eye drops which has anesthetic and anti-inflammatory effects.


The session lasts between 10 and 15 minutes, and the patient experience no pain during it. It uses a YC-200 S PLUS laser that acts at a wavelength of 532 nanometers and in a space of time of 3 nanoseconds, producing the selective heating of the pigmented cells of the trabecular meshwork, without burning them.

In this way, a inflammatory reaction that cleans and stimulates these cells, making them work better and the aqueous humor of the eyeball.


For a few weeks a mild anti-inflammatory eye drops will be applied. The patient can develop his life normally after treatment.

However, the effects of selective laser trabeculoplasty are not instantaneous, so it is necessary to maintain the treatment of ocular hypotension.

After that time, the SLT laser treatment should have produced its maximum effects. At this point, its effectiveness can be evaluated.

SLT laser treatment for glaucoma does not require hospitalization of the patient, who in the following days and weeks can lead a normal life once the effect of the drops wears off.

Possible risks of the SLT laser

It is common for inflammation, although in most cases it is usually mild and is treated by observation, eye drops, or an oral non-steroidal anti-inflammatory drug.

Also, after the laser is produced around a 5% incidence of elevated intraocular pressure, that can be controlled with the same glaucoma drugs. Normally, it disappears after 24 hours.

In which patients is it recommended?

It will be the ophthalmologist who decides if selective laser trabeculoplasty is appropriate for the patient. In principle, the SLT is indicated in cases of primary or secondary open-angle glaucoma (where the drainage system in the front of the eye is open) and where it is necessary reduce intraocular pressure.

On the other hand, laser treatment is contraindicated in patients with Narrow angle glaucoma or keratopathies that make it difficult to see the angle and trabeculum correctly, as well as those with inflammatory or traumatic glaucomas.

This laser treatment can be performed in patients previously treated with Argon Laser Trabeculoplasty, with the same efficacy as the previous treatment. However, a lower blood pressure drop is foreseeable in patients who have undergone glaucoma surgery, so TLS is not recommended in these cases.

Side effects of SLT in glaucoma

The side effects of SLT they are usually minimal or mild. As we have seen, in 5% of patients there is a ocular hypertension peak, and also a inflammatory reaction ocular insignificant.

These symptoms can be controlled with hypotensive medication and, in any case, in the days after the treatment, the intraocular pressure should be measured regularly.

En Área Oftalmológica Avanzada we are experts in treating with SLT laser. If you think that this can be an effective solution in your case, you just have to contact us. We will wait for you!

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Discover everything you need to know about the SLT laser
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Discover everything you need to know about the SLT laser
Selective Laser Trabeculoplasty (SLT) is a safe and effective laser treatment. It is presented as an alternative for patients with ocular hypertension or primary or secondary open-angle glaucoma.
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Área Oftalmológica Avanzada
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