Medically reviewed by Dr. Niranjana Bejan Singh. Written to established clinical-education standards (AAO/Mayo/NHS/NEI) and adapted for this hospital. Not a substitute for professional medical advice.
Selective laser trabeculoplasty (SLT) is a quick, in-office laser treatment that lowers eye pressure in open-angle glaucoma by improving fluid drainage through the eye's natural drainage tissue, called the trabecular meshwork. The laser targets specific pigmented cells in this tissue without causing the wider thermal damage associated with older laser techniques, which is why it can often be repeated if needed. SLT is used both as an initial treatment for open-angle glaucoma or elevated eye pressure (ocular hypertension), and as an addition when drops are not fully controlling pressure. It does not involve any incision and does not require anesthesia beyond numbing eye drops.
Who typically needs this
- Often offered as a first-line treatment option for open-angle glaucoma or ocular hypertension, as an alternative to starting with eye drops.
- Considered for patients already on glaucoma drops whose eye pressure is not fully controlled, or who want to reduce their number of daily medications.
- Suitable for patients who have difficulty using eye drops consistently or who experience side effects from glaucoma medications.
- Not typically effective for angle-closure glaucoma, since it requires an open drainage angle to work.
What to expect
- Performed in the clinic using numbing eye drops; no incision or sedation is needed.
- A special contact lens is placed on the eye to help the surgeon aim the laser at the trabecular meshwork.
- The laser is applied in a series of brief, low-energy pulses around the drainage angle.
- The entire treatment usually takes only a few minutes per eye.
- Eye pressure is checked shortly after treatment before the patient goes home.
Recovery
- Most patients resume normal activities the same day, with little to no downtime.
- Mild eye irritation, redness, or blurred vision for a day or two is common.
- Anti-inflammatory drops may be prescribed for a short period after treatment.
- The full pressure-lowering effect may take several weeks to become apparent, and a follow-up visit is scheduled to check the response.
Risks to know about
- Eye pressure can rise temporarily in the hours after treatment, which is why pressure is checked before discharge.
- Mild inflammation inside the eye is common and usually settles with drops.
- The effect of SLT can wear off over time, and some patients eventually need repeat treatment or additional therapy.
- SLT does not work for everyone; a minority of patients see little or no drop in eye pressure.
Frequently asked questions
Does SLT hurt?
Most patients feel little to no discomfort. The eye is numbed with drops beforehand, and the laser pulses are brief.
Can SLT replace my eye drops completely?
For some patients it reduces or eliminates the need for drops, but others still need medication alongside SLT to reach their target pressure.
Can SLT be repeated?
Yes. Unlike older laser techniques, SLT causes minimal tissue damage, so it can often be repeated if the effect wears off.
How soon will I know if it worked?
The full effect typically takes several weeks to develop, so eye pressure is usually rechecked about a month after treatment.
Ready to see us?
Call the appointment desk, or book online — we will confirm your time by phone.
Sources consulted: AAO — SLT and DSLT Laser Surgeries for Glaucoma, NEI — Laser Treatment for Glaucoma . General medical information — not a substitute for professional diagnosis. Medically reviewed by Dr. Niranjana Bejan Singh.
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