Laser-1st vs Drops-1st for Glaucoma and Ocular Hypertension

Subjects are randomly allocated to one of two treatment arms that examine treatment pathways, rather than comparing single treatments alone: 'initial Selective Laser Trabeculoplasty (SLT) followed by conventional medical therapy as required' ('Laser-1st') and 'medical therapy without laser ('Medicine-1st'). We compare quality of life in the two pathways (arms) over three years, while also examining the incremental cost and cost-effectiveness of Laser-1st versus Medicine-1st.

A 'Treat in Pursuit of Control' design (TPC) compares two different routes to a pre-defined target Intraocular pressure (IOP) (pathways). It is a pragmatic study that uses published guidelines to make the complex clinical treatment choices faced in managing glaucoma, standardised between treatment arms by use of computer treatment algorithms. A UK National Institute for Health and care Excellence (NICE)-compliant evidence-based IOP Treatment Target 1 is set for each patient, according to the study treatment algorithms. They then proceed through stepped increments of treatment intensity (up to and including surgery) until a predetermined Target IOP is reached. Target IOP is reassessed in the light of objective clinical evidence of stability of glaucomatous optic neuropathy (GON) and visual function using visual field tests and automated optic nerve evaluation. Health Related Quality of Life (HRQL) and secondary outcomes are compared for patients in each pathway.

Inclusion criteria

• Diagnosis of open angle glaucoma (defined as an open drainage angle and reproducible glaucomatous visual field defects as tested by the Swedish Interactive Threshold Algorithm (SITA) algorithm on the Humphrey Visual Field or glaucomatous optic neuropathy)
• OR
• Ocular hypertension (intra-ocular pressure above 21mmHg and requiring treatment as per National Institute of Health and Care Excellence (NICE) Guidelines).
• Able to provide informed consent.

Exclusion criteria

• Advanced glaucoma in the potentially eligible eye as determined by Early Manifest Treatment Guidelines (EMGT) criteria 77: visual field loss mean deviation worse than -12dB in the better or -15dB in the worse eye.
• Secondary glaucoma (e.g. pigment dispersion syndrome, rubeosis, trauma etc) or any angle closure.
• Any contra-indication to selective laser trabeculoplasty (e.g. unable to sit at the laser-mounted slit-lamp; past history of uveitis).
• Unable to use topical medical therapy due to e.g. physical infirmity and a lack of carers able to administer daily eye-drops.