Radiotherapy robot improves treatment and reduces cost for eye disease, trial finds

Researchers from King’s College London have successfully used a robotic system to improve treatments for a debilitating eye disease by using stereotactic radiotherapy.

A custom-built robot capable of administering a “one-off, minimally invasive” dose of radiation was used to treat wet neovascular age-related macular degeneration (Wet AMD), before treatment continued with routine eye injections.

The trial, published in The Lancet and performed with doctors at King’s College Hospital NHS Foundation Trust, found patients consequently needed fewer injections to control the disease.

It estimated the technology could save around 1.8 million injections per year around the world.

A landmark treatment

The trial, which found the cost of the stereotactic radiotherapy was more than offset by the reduced costs associated with fewer injections, was described in The Lancet as a “landmark” for treatment of Wet AMD. 

The treatment’s improved targeting involves aiming three beams of focused radiation into the diseased eye. The decreased requirement for future injections means the device could save the NHS £565 for each patient treated over the first two years.

Wet AMD consists of abnormal blood vessels growing into the light-sensing layers of cells at the back of the eyeball, which start leaking blood and fluid and cause rapid, permanent, and severe loss of sight.

It is currently treated with regular injections, but this is only a stopgap measure – most require this injection every one to three months, and each injection costs between £500 and £800. 

These injections have become “one of the most common NHS procedures,” King’s College London said.

Around 196 million people around the world suffer from this disease, and it is estimated to affect more than 700,000 people in the UK.

This is expected to increase by 60 per cent by 2035 thanks to the country’s ageing population.

'We can be incredibly precise'

Research has previously tried to find a better way to target radiotherapy to the back of the eyeball, such as by repurposing devices used to treat brain tumours, but technology has not been precise enough.

Timothy Jackson, professor of retinal research, consultant ophthalmic surgeon, and lead author, said: "With this purpose-built robotic system, we can be incredibly precise, using overlapping beams of radiation to treat a very small lesion in the back of the eye.

“Patients generally accept that they need to have eye injections to help preserve their vision, but frequent hospital attendance and repeated eye injections isn’t something they enjoy. By better stabilising the disease and reducing its activity, the new treatment could reduce the number of injections people need by about a quarter. Hopefully, this discovery will reduce the burden of treatment that patients have to endure.”

The research was jointly funded by the National Institute for Health and Care Research (NIHR) and the Medical Research Council (MRC) and recruited 411 participants across 30 NHS hospitals. A Lancet-commissioned commentary that accompanied the article described it as a “landmark trial”.

This study was led by researchers from King’s College London and doctors at King’s College Hospital NHS Foundation Trust, in collaboration with the University of Oxford, the University of Bristol and Queen’s University in Belfast.

(Image: King's College London)