Exploring the eye with a light brighter than the sun

Viewed from above, with the proportions of a giant silver frisbee, the UK’s national synchrotron in Oxfordshire could be a sports stadium or the first signs of an alien landing.

Instead, inside this state-of-the-art facility, scientists work on projects from increasing the shelf life of perishable food to analysing coatings used in the design of aeroplanes.

Cardiff University School of Optometry and Vision Sciences senior lecturer, Dr Craig Boote, told OT that when he first used a predecessor to the current national synchrotron during his PhD research, he was staggered by the size of the facility.

“It takes about 20 minutes to just walk around the outside of the building because it is so large,” he shared.

“What also struck me was the variety of research that goes on. It is not just biological tissues and looking at disease, like my research, but also, for example, the food industry is using synchrotrons to study the crystallisation of chocolate,” Dr Boote observed.

The Diamond Light Source synchrotron works by accelerating electrons to close to light speeds so that they give off light 10 billion times brighter than the sun.

These bright beams are then directed off into laboratories known as ‘beamlines’, where scientists can study a broad variety of materials using a machine that is 10,000 times more powerful than traditional benchtop instruments.

Dr Boote explained to OT that his research used the synchrotron to examine the donor eyes of glaucoma patients and healthy controls.

He highlighted that while many people with glaucoma have high intraocular pressure, there are some patients who develop glaucoma with apparently normal pressure in the eye.

“We are looking at the structure of the collagen protein in the back of the eye that supports the optic nerve because we believe that changes there predispose people to optic nerve damage,” Dr Boote shared.

Most treatments for glaucoma focus on lowering intraocular pressure, but this approach is not effective for all patients.

Dr Boote’s research has focused on identifying what happens in the eye in the early stages of the disease in order to design potential treatments to address these changes.

“By targeting the back of the eye with other treatments we may be able to help people who are going blind even without high pressure,” he emphasised.

Having access to the synchrotron was invaluable for his research, Dr Boote highlighted.

“It is basically the only way we can get enough information at the speed required. If you used a standard X-ray machine in a laboratory, it would take about eight hours to get one piece of data from one position in the eye – and we routinely sample thousands of positions. With a synchrotron, that single data point takes one second to collect,” Dr Boote explained.

As well as glaucoma, the synchrotron is being used to provide new insight into myopia. The technology is ideal for observing how the eye remodels in short-sightedness, Dr Boote said.

“It gives you a holistic view of the eye. You need to look at the eye as a whole to understand what happens in pathology, and how different eye diseases and their risk factors may be connected,” he concluded.

Image credit: Diamond Light Source