Selective Laser Trabeculoplasty, or SLT, is a recently developed technology, which is an effective and repeatable treatment for patients with open-angle glaucoma.
It is suitable as:
- First-line treatment once glaucoma is diagnosed in order to minimize the usual need for daily eye drops.
- An alternative for patients already on eye drops if they are inconvenient or causing side effects.
- Additional treatment to eye drops in patients with more advanced glaucoma, to minimize the need for surgery.
What is involved?
You will sit at a machine which is similar in appearance to the microscope you may be familiar with in the eye clinic. An anaeasthetic eye drop allows a contact lens to be comfortably applied to your eye, in order to focus the laser.
The procedure takes 5-10 mins and is painless. Your eye pressure will be checked one hour later.
You can resume normal activities immediately.
Usually, the treatment is applied in 2 stages (180 degrees at a time) separated by a few weeks. I will check your eye pressure again 6-8 weeks after the second session of laser treatment.
What should I expect afterwards?
You may experience mild discomfort, blurring of vision and increased sensitivity to sunlight for 2-3 days after the procedure.
You can resume normal activities immediately.
You will be asked to continue your normal glaucoma drops if you are already taking them until your follow up appointment.
How does it work?
Laser energy is applied to the trabecular meshwork to cause better drainage of fluid out of the eye. This eventually results in lowering of IOP. It differs from the old-style argon laser in that it leads to minimal heat energy absorption because it is only taken up by selected pigmented tissue in the eye. As such, it is referred to as a “cold laser”, producing less scar tissue and has minimal pain.
How effective is it?
Studies show that SLT is effective in 90% of cases at one year. It lowers the IOP by about 30% when used as initial therapy. This is comparable to the pressure-lowering effect of the most powerful and commonly used class of glaucoma medication (prostaglandin analogues). This effect may be reduced if the patient is already on glaucoma medications.
It may take 1-3 months for the full intraocular pressure lowering effect to occur.
SLT does wear off in some patients and the success rate 5 years later is approximately 50%. However, one of the advantages of this new laser is that it can be repeated 4 or 5 times with equal chance of success.