The content of this website is intended for healthcare professionals only

Hopes for early warning glaucoma detector

New test could reveal signs of change a decade before damage is done

Mark Gould

Friday, 28 April 2017

Scientists say that early trials of a new type of eye examination might be able to spot glaucoma a decade before symptoms appear.

Current treatments to control the eye's internal pressure can stop or slow down the progression of the disease, which affects retinal cells, although they cannot reverse the damage already done.

Writing in the journal Brain,* researchers from University College London (UCL), describe a new imaging technique, called DARC (detection of apoptosing retinal cells), which uses a fluorescent dye to identify retinal cell apoptosis.

In glaucoma, changes to the pressure inside the eye kills the retina's nerve cells. As these cells become stressed and sickly, they start to change their chemistry and more fatty structures move to the outside of the cell. The fluorescent dye, which is injected into the bloodstream, targets these apoptosing cells and sticks to them and shows them up as white fluorescent dots under routine examination with an ophthalmoscope.

In Phase I clinical trials, on just 16 patients, the technique could spot the difference between the eyes of healthy patients and those with glaucoma. Researchers say that larger trials are needed to confirm the validity of their findings.

Prof Francesca Cordeiro, from the UCL Institute of Ophthalmology, told the BBC News website: "For the first time in humans we have a test that identifies [glaucoma] disease activity before the disease develops. "We are possibly talking five to 10 years before it would normally be identified."

And as a footnote, the researchers observe: "An interesting post hoc finding in the present study has been the significant relationship of a high DARC count being predictive of increased rates of progression, suggesting that DARC could potentially be prognostic of neurodegenerative activity."

Animal research suggests neurodegenerative diseases might be visible in the decay of nerve cells - which anatomically are simply an extension of the brain - too. An eye exam would be a cheap way of monitoring the progression of diseases like dementia, Parkinson's or multiple sclerosis than a brain scan.

Bethan Hughes, from the Wellcome Trust, which funded the research, said: "This innovation has the potential to transform lives for those who suffer loss of sight through glaucoma, and offers hope of a breakthrough in early diagnosis of other neurodegenerative diseases.

* Cordeiro MF, Normando EM, Cardoso MJ, et al. Real-time imaging of single neuronal cell apoptosis in patients with glaucoma. Brain, published: 26 April 2017. DOI: 10.1093/brain/awx088

Registered in England and Wales. Reg No. 2530185. c/o Wilmington plc, 5th Floor, 10 Whitechapel High Street, London E1 8QS. Reg No. 30158470