Selective Laser Trabeculoplasty (SLT)
SELECTIVE LASER TRABECULOPLASTY (SLT) FOR GLAUCOMA
Selective Laser Trabeculoplasty (SLT) is a relatively safe, simple and usually painless laser procedure that helps to reduce the eye pressure associated with glaucoma or ocular hypertension. SLT stimulates the structure inside the eye, called trabecular meshwork, allowing more fluid drainage from the canals that surround the iris (coloured disc of the eye), thus reducing eye pressure.
SLT is performed in the eye clinic and typically takes no longer than five minutes for each eye to do. It is performed using a specialized slit lamp with a small contact lens on the eye following instillation of topical local anaesthetic.
In about 7 out of 10 people eye pressure is improved following SLT. It can take a few months for SLT to have its full effect on lowering eye pressure. If successful, the effect may last for a few years. SLT may be repeated, if necessary, normally at six months or later.
Why do I need to have it done?
The most common reasons for your doctor to offer you SLT treatment are:
Your eye pressure is considered too high for your level of glaucoma.
You are suffering with side effects from your current eye drops.
You find it difficult to cope with regular eye drops.
What will happen during the procedure?
The SLT procedure typically takes 3 to 5 minutes for each eye to do. A special contact lens is used to keep your eyelids open. Anaesthetic eye drops are applied to ensure that your eye is comfortable with the lens in your eye. The laser machine looks very similar to the microscope used for examining your eyes. You may hear some beepng sounds produced by the laser machine.
The procedure itself is generally painless. Most patients do not experience any significant discomfort, although some may feel a little pressure inside the eye or a slight headache during or after the SLT procedure.
Treatment can be done to one eye or both eyes in a single sitting.
What will happen after the procedure?
We normally check the eye pressure about 30 minutes after the laser treatment.
Usually, you will be seen again for further eye pressure monitoring between 6 to 8 weeks following the treatment.
If you are using anti-glaucoma eye drops before SLT, you should continue using the same treatment, unless advised otherwise by your doctor.
Normally, there is no need for additional drops after SLT, but this will depend on your eye pressure measurements and inflammation following the procedure.
No aftercare or precautions are needed following SLT and you will be able to resume wearing contact lenses and return to your normal activities from the following day.
What are the side effects?
SLT is usually a safe procedure and the risk of adverse effects is minimal. There is a small risk of raised eye pressure for a short period of time after the laser treatment. To prevent this, you may be given additional eye drops before and /or after the procedure. One of the eye drops (Pilocarpine) can cause a transient headache for up to 1 hour after instillation.
You might experience some eye discomfort and redness, blurry vision or sensitivity to light after the laser for a few hours or sometimes a few days, for which you might want to wear sunglasses.
There have been very few reports of serious problems after SLT. The reported cases were bleeding of the iris, swelling of the retina (back of the eye) and swelling of the cornea (front transparent window of the eye). Most peoples’ eyes settle down without any further problems.
Very rarely, the eye pressure may go up and be difficult to control with eye drops. This may mean we would need to do a glaucoma operation.
There have not been any reports of SLT making the vision permanently worse, except in eyes that already had poor vision due to other co-existing eye conditions.
Information and support
We hope you have found this information helpful. If you have any questions or anxieties, please feel free to speak to a member of our staff.