Selective Laser Trabeculoplasty (SLT) is a safe, effective and minimally invasive laser treatment used to lower eye pressure in patients with glaucoma and ocular hypertension. It is performed as an outpatient procedure and may reduce or eliminate the need for daily glaucoma eye drops in some patients.
At our private ophthalmology clinic in Glasgow, Dr Young provides comprehensive assessment and personalised treatment plans for patients with glaucoma and raised intraocular pressure (IOP), including advanced laser treatments such as SLT.
Selective Laser Trabeculoplasty (SLT) is a laser procedure that improves drainage of fluid from the eye through the trabecular meshwork—the eye's natural drainage system. By improving fluid outflow, SLT lowers intraocular pressure (IOP), which is the most important modifiable risk factor for glaucoma progression.
Unlike older laser treatments, SLT selectively targets pigmented cells within the drainage tissue while causing minimal thermal damage to surrounding structures. This makes the procedure safe, repeatable in selected cases, and associated with a low risk of complications.
SLT is now usually recommended as first line treatment for:
Primary Open-Angle Glaucoma (POAG)
Ocular Hypertension (raised eye pressure without glaucoma damage)
It can also be used for:
Pseudoexfoliative Glaucoma
Pigmentary Glaucoma
Selected cases of secondary open-angle glaucoma
At your appointment, Dr Young will determine whether SLT is appropriate based on your eye examination findings, optic nerve assessment, visual field testing and eye pressure measurements.
Glaucoma is a progressive condition that damages the optic nerve and can lead to permanent vision loss if left untreated.
The aim of treatment is to reduce intraocular pressure sufficiently to slow or prevent further optic nerve damage. Lowering eye pressure is currently the only proven method of reducing the risk of glaucoma progression.
The eye continuously produces a clear fluid called aqueous humour. This fluid drains through a microscopic sieve-like structure known as the trabecular meshwork.
In many patients with glaucoma, fluid drainage becomes less efficient, causing eye pressure to rise.
SLT uses short pulses of low-energy laser light directed at the trabecular meshwork. The laser stimulates a biological response that improves drainage and increases fluid outflow, resulting in a reduction in intraocular pressure.
Pressure reduction typically develops gradually over several weeks and may continue to improve for up to three months after treatment.
SLT has become an increasingly important treatment option for glaucoma and ocular hypertension.
The landmark UK LiGHT Trial demonstrated that SLT can be used safely and effectively as a first-line treatment for many patients with ocular hypertension and mild-to-moderate open-angle glaucoma. After three years, approximately 78% of eyes treated initially with SLT maintained target eye pressure without requiring glaucoma drops, and SLT was shown to be cost-effective compared with initial medical therapy.
Longer-term follow-up has shown that patients treated with SLT may experience slower disease progression and reduced need for glaucoma surgery compared with those managed initially with eye drops alone.
SLT is performed in the outpatient clinic and usually takes around 5–10 minutes per eye.
You will receive:
Anaesthetic eye drops to numb the eye
Occasionally, drops to prepare the eye for treatment
A brief eye examination
A special contact lens is gently placed on the eye and the laser is applied to the drainage angle.
Most patients experience:
Little or no pain
Occasional mild discomfort
Bright flashes of light during treatment
You can usually go home shortly afterwards.
Your vision may be slightly blurred for several hours, and some patients notice mild redness or irritation for a day or two.
A follow-up appointment will be arranged to assess your eye pressure response.
Potential advantages include:
No daily eye drops required in some patients.
Reduction in the number of glaucoma medications.
Improved treatment adherence.
Quick outpatient procedure.
Minimal recovery time.
Excellent safety profile.
Can be repeated in selected patients.
Avoids many side effects associated with long-term glaucoma drops.
For many patients, SLT offers an opportunity to reduce dependence on lifelong medication while maintaining effective control of intraocular pressure.
SLT is considered a very safe procedure, but as with any medical treatment, complications can occur.
Possible risks include:
Temporary blurred vision
Mild eye discomfort or irritation
Temporary inflammation
Temporary rise in eye pressure
Inadequate pressure reduction
Need for repeat laser treatment
Ongoing requirement for glaucoma drops or surgery
Serious complications are uncommon.
At your appointment Dr Young will discuss the benefits and risks in relation to your individual circumstances before treatment.
The effect of SLT varies between individuals.
Many patients experience pressure reduction lasting several years. In some cases, the effect gradually diminishes over time. If appropriate, repeat SLT treatment may be considered.
Even when glaucoma drops are still required, SLT often reduces the number of medications needed to achieve target pressure.
SLT may be suitable if you:
Have ocular hypertension
Have open-angle glaucoma
Wish to reduce dependence on glaucoma drops
Experience side effects from eye medications
Have difficulty remembering regular eye drops
A comprehensive glaucoma assessment is required before treatment recommendations can be made.
Choosing an experienced glaucoma specialist ensures that treatment recommendations are tailored to your individual risk profile, lifestyle and long-term visual needs.
At our Glasgow private eye clinic, Dr Young offers:
Consultant-led glaucoma assessment
State-of-the-art diagnostic imaging
Visual field testing
Personalised treatment planning
Advanced laser treatments including SLT
Ongoing glaucoma monitoring and care
Our goal is to preserve vision and maintain quality of life through evidence-based glaucoma management.
To book an appointment to see Dr Young please email drsuyoung@gmail.com or visit https://www.circlehealthgroup.co.uk/consultants/su-ling-young
Gazzard G, Konstantakopoulou E, Garway-Heath D, et al. Selective Laser Trabeculoplasty versus Eye Drops for First-Line Treatment of Ocular Hypertension and Glaucoma (LiGHT): A Multicentre Randomised Controlled Trial. Lancet. 2019;393(10180):1505–1516.
National Institute for Health and Care Excellence (NICE). Glaucoma: Diagnosis and Management. Evidence Review for Selective Laser Trabeculoplasty. 2022.
European Glaucoma Society. Selective Laser Trabeculoplasty (SLT) Can Be Considered as First Treatment for Newly Diagnosed Ocular Hypertension and Mild to Moderate Primary Open-Angle Glaucoma.
Konstantakopoulou E, et al. The Laser in Glaucoma and Ocular Hypertension (LiGHT) Trial: Baseline Characteristics. British Journal of Ophthalmology. 2018.
Recent long-term LiGHT Trial follow-up data presented at the American Academy of Ophthalmology demonstrating slower glaucoma progression and reduced need for surgery following primary SLT treatment.