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Selective Laser Trabeculoplasty (SLT)

Selective Laser Trabeculoplasty or SLT is a form of laser used to lower the pressure in the eye for glaucoma or ocular hypertension. It is used when the eye drop medications are not lowering the pressure enough or when the medications used are causing side effects. It is also sometimes used as an initial treatment for glaucoma. 

SLT has been used for at least a decade in other countries such as the USA and about 5 years in the UK. This article is written to answer the common questions patients ask regarding the treatment and the clinical experience of users around the world.

1. Who is a candidate for SLT?
Patients who have open-angle glaucoma - the drainage system in the front of the eye is open but who require further intraocular pressure (IOP) lowering are eligible for the procedure.  Your ophthalmic consultant will make the final determination if you are a candidate.

2. How does it work?
Laser energy is applied to the drainage tissue in the eye. This starts a chemical and biological change in the tissue that results in better drainage channels out of the eye. This should result in the lowering of IOP. It may take 1-3 months for the improvements to appear.

3. Why is it called selective?
The type of laser used has minimal heat energy absorption because it is only taken up by selective pigmented tissue in the eye. Sometimes it is referred to as “cold laser”. Because of this, the procedure produces less scar tissues and minimal pain.

4. How long does the effect last?
This treatment will generally last between 1-5 years and in rare cases longer than that. If it does not last at least 6-12 months it is not usually considered successful.

5. What happens if it wears off?
If the SLT is effective in lowering the IOP but wears off after several years the procedure can be repeated but the second treatment may not be as effective as the first and may not last as long. If SLT has not been successful, a repeat treatment is unlikely to work. 

6. What happens if it does not work?
If SLT fails to lower IOP glaucoma medication can be used or alternatively conventional surgery. The laser does not affect the success of these types of treatment.   

7. Will I still need to use glaucoma medication?
Some patients can be controlled with laser treatment alone. Others will require additional IOP lowering and may therefore, need to use glaucoma medication as well. It is best to think of SLT as equivalent to one medication. Just as some patients will require more than one type of medication to control their IOP some may require laser and medication.

If you have any further questions please contact Rivers Hospital on 01279 602628

Content provided by Mr Petros Andreou, Consultant Ophthalmologist.

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