Comparative outcomes of selective laser trabeculoplasty delivered by optometrists compared with ophthalmologists: a UK-based multicentre observational study

Abstract

Background: Selective laser trabeculoplasty (SLT), a National Institute for Care and Health Excellence recommended first-line treatment for open-angle glaucoma and ocular hypertension, is increasingly delivered by optometrists. This retrospective multicentre observational study evaluates real-world outcomes of SLT comparing optometrist-treated to ophthalmologist-treated eyes.

Methods: Adults aged ≥40 years receiving first SLT treatment at three UK hospital eye units (Aintree, Manchester, Macclesfield) between 1 August 2018 and 1 August 2021 were analysed using anonymised local audit data. Outcomes included intraocular pressure (IOP), visual acuity (VA), drop burden, complications including post-SLT IOP spikes, and composite treatment failures including repeat laser or glaucoma surgery, evaluated at 6-monthly intervals up to 24 months. Groups were compared with parametric and non-parametric tests, accounting for intereye correlation, and Kaplan-Meier survival analysis using composite treatment failure endpoints was conducted.

Results: 207 eyes (131 patients) were analysed, 84 (56 patients) optometrist-treated eyes compared with 123 ophthalmologist-treated eyes (75 patients). No statistically significant differences (p>0.05) were found in change in VA, IOP or glaucoma drops from pre-SLT baseline between optometrist and ophthalmologist-treated eyes, at all time points. More cataracts were detected in optometrist-treated eyes, however, this did not affect differences in VA or cataract surgery frequency. More optometrist-treated eyes underwent glaucoma surgery, however, ophthalmologist-treated eyes had higher drop burden and chance of composite treatment failure up to month 18.

Conclusion: Outcomes of SLT treatment by optometrists and ophthalmologists are comparable up to 24 months post-treatment. Ophthalmologist-treated eyes may have had more aggressive eye-drop treatment, preventing the need for surgery.

Keywords: Glaucoma; Intraocular pressure; Treatment Lasers.

Figure 1. Mean intraocular pressure (IOP) of optometrist versus ophthalmologist-treated eyes over time. Mean intraocular pressure between optometrist-treated and ophthalmologist-treated eyes. Error bars show the 95% confidence interval.

Figure 2. Kaplan-Meier probability of failure curve. Kaplan-Meier probability of failure curve showing the cumulative risk of failure at respective time points between optometrist-treated compared with ophthalmologist-treated eyes.