Author: Claude (AI), from PubMed abstracts · Reviewed by: Dr Mina Abdelmseih · Reviewed: 2026-11-15 · Review due: 2027-11-15

Educational content only. Not personalised medical advice. Clinical decisions remain the responsibility of the treating clinician.

Selective Laser Trabeculoplasty as First-Line Treatment

Selective laser trabeculoplasty (SLT) lowers intraocular pressure (IOP) in open-angle glaucoma (OAG) and ocular hypertension (OHT) as well as eye drops [S4] [S12], without depending on daily adherence. In the LiGHT trial, first-line SLT gave drop-free control to 74.2% of patients for at least 3 years at lower cost [S2], and in Tanzania SLT was superior to timolol at 1 year [S6].

Key points - A Cochrane review found laser trabeculoplasty may slow visual field progression compared with drops and control IOP similarly at lower cost, without serious adverse effects for SLT [S7]. - In LiGHT at 6 years, 69.8% of SLT eyes stayed at or below target IOP without drops or surgery, with less progression and fewer trabeculectomies and cataract operations than drops [S8]. - In a Tanzanian RCT, treatment success at 12 months was 61% with SLT vs 31% with twice-daily timolol (OR 3.37) [S6]. - 360-degree treatment at higher energy gave the largest and longest-lasting IOP reduction [S9] [S10]. - Repeat SLT maintained drop-free control in 67% of retreated eyes at 18 months [S3].

Evidence last checked: 2026-10-17 (PubMed abstracts).

Red flags

• Post-laser IOP spike: early IOP spikes occurred in 5% of SLT-treated participants [S7].
• Failure to reach target: in Tanzania, 33 of the 99 successfully treated SLT eyes had needed a repeat SLT [S6]. Do not assume one session is enough.
• Wrong patient: trials enrolled open-angle glaucoma and OHT [S2] [S6]; LiGHT excluded secondary and childhood glaucoma and advanced field loss [S2].

Recognise it: who is suitable

• Newly diagnosed, treatment-naive OAG or OHT, as in LiGHT [S2] [S8].
• Open-angle glaucoma with IOP above 21 mmHg in sub-Saharan Africa, including where advanced glaucoma is common [S6].
• Afro-Caribbean eyes with POAG: SLT as sole therapy gave 78% success at 12 months in St Lucia and Dominica [S1].
• Patients already on drops: the long-term meta-analysis found SLT reduced medication use by 0.87 drugs [S12].

Confirm it: before and after laser

• Trials defined success against a target IOP set by severity [S6] or a 20% reduction from washout baseline [S1].
• Assess IOP response at 1 to 6 months [S9]; LiGHT triggered retreatment using predefined IOP and progression criteria [S3].

Manage it: performing SLT

Before acting on this section, check the national and local guidelines, product information and regulatory approvals that apply where you practise. See the medical disclaimer.

Tier A (primary care / no specialist)

• Tier A has no laser role. Explain to patients that laser is an alternative to lifelong drops [S2] [S6], and refer suspected glaucoma to an eye service [G1].

Tier B (general eye clinic)

1. Offer SLT first to newly diagnosed OAG and OHT where a laser is available [S2] [S8]. In Tanzania it outperformed the standard low-cost drop, timolol [S6].
2. Treat 360 degrees. 360-degree SLT reduced IOP by 1.15 mmHg more than 180-degree at 1 year, with higher success and no more serious complications [S10]. In the Swedish RCT, 360 degrees at high energy (cavitation bubbles in 50% to 75% of shots, about 100 spots, as reported in [S9]) lowered IOP by 5.4 mmHg vs 3.2 to 4.2 mmHg for other protocols and doubled the time to escalation [S9].
3. Skip routine anti-inflammatory drops. Topical NSAIDs or steroids after SLT did not change IOP reduction, discomfort or anterior chamber inflammation in a meta-analysis of 5 RCTs [S5].
4. Expect mild symptoms. Transient photophobia and discomfort were common [S1]; discomfort was more frequent with high-energy 360-degree treatment but mild [S9].
5. Repeat when needed. Repeat SLT had at least an equivalent duration of effect to the first treatment [S3]; repeat SLT was permitted once in the Tanzanian trial [S6].

Tier C (specialist centre)

• Direct SLT. An automated, gonioscopy-free, non-contact device did not meet non-inferiority at 6 months but was non-inferior at 12 months; it may be considered first-line where conventional SLT is not accessible [S11].
• Laser types. All laser trabeculoplasty types lowered IOP similarly to medication in a network meta-analysis [S4]; argon laser was associated with peripheral anterior synechiae [S7].
• Compared with surgery. Argon laser trabeculoplasty may leave more eyes with uncontrolled IOP at 24 months than trabeculectomy (16% vs 8%, low certainty) [S7].

Refer when

Pitfalls

• Treating only 180 degrees at low energy [S9] [S10].
• Prescribing anti-inflammatory drops routinely [S5].
• Abandoning laser after an early failure; repeat SLT works [S3].
• Assuming laser is only for patients who fail drops [S2] [S7].

Evidence notes

• Most Cochrane trials were unmasked and conducted in Europe and the USA [S7]; the Tanzanian and Caribbean trials add African-ancestry evidence but follow-up was only 12 months [S1] [S6].
• LiGHT was unmasked and used a generic quality-of-life tool [S2].
• Energy settings in [S9] are described by cavitation response, not in millijoules in the abstract.
• Not covered by these sources: SLT in angle closure, pigmentary or pseudoexfoliation glaucoma, laser purchase and maintenance cost in low-income settings, and training requirements.

Related articles

• Glaucoma Medications: Choices, Adherence and Side Effects
• Primary Open-Angle Glaucoma: Diagnosis and Treatment Targets
• Minimally Invasive Glaucoma Surgery (MIGS)

References

See the numbered source list below. Each marker [S#] links to its PubMed and DOI record.