Eye test ‘detects Parkinson’s before symptoms appear’ — so far just in rats

    25 August 2016

    A non-invasive eye test developed by researchers at University College London could detect Parkinson’s disease before symptoms emerge, according to a report in the journal Acta Neuropathologica Communications.

    The inexpensive test, which has been tested on rats, involves observing changes in the retinas of Parkinson’s patients before changes occur in the brain. The technique has also been tested in humans for glaucoma.

    Parkinson’s is estimated to affect between 51,000 and 120,000 people in the UK. Symptoms, which include muscle stiffness, slowness of movement and tremors, only appear once over 70 per cent of the brain’s dopamine-producing cells have been destroyed.

    The test, which uses commonly available ophthalmic instruments, would allow earlier diagnosis of Parkinson’s and also could be used to monitor how patients respond to treatment.

    Francesca Cordeiro, professor of glaucoma and retinal neurodegeneration studies, who led the research, said: ‘This is potentially a revolutionary breakthrough in the early diagnosis and treatment of one of the world’s most debilitating diseases.

    ‘These tests mean we might be able to intervene much earlier and more effectively treat people with this devastating condition.’

    The study’s first author, Dr Eduardo Normando, said: ‘These discoveries have the potential to limit and perhaps eliminate the suffering of thousands of patients if we are able to diagnose early and to treat with this new formulation.’

    Instant analysis
    This research is very much in its infancy and the authors’ conclusions are based on their findings in rats; there is clearly a long way to go before these results are directly applicable to human subjects.

    The researchers found that certain retinal changes in Parkinson’s disease preceded other pathological features which are currently looked for in order to make the diagnosis. These retinal changes may, postulate the authors, be a useful surrogate biomarker for Parkinson’s, and could in time be used to assess new treatments. The research also demonstrated that the use of a newly formulated version of rosiglitazone (an anti-diabetic drug) led to less cell damage in Parkinson’s disease. The research methodology seems robust but limited in scope.

    At present, the findings remain a promising foundation for further work but do not, I think, represent a ‘breakthrough’.
    Research score: 3/5