Eyes Reveal Parkinson’s Signs Up To Seven Years Before Diagnosis, Study Finds

MARKERS indicating the presence of Parkinson’s disease in patients, an average of seven years before clinical presentation, have been discovered.

‘Neurology’, the medical journal of the American Academy of Neurology published the results by research teams from University College London (UCL) and Moorfields Eye Hospital.

These results were made possible by the largest study to date on retinal imaging in Parkinson’s disease.

The study identified Parkinson’s markers in eye scans with the help of artificial intelligence (AI). Their analysis of the AlzEye dataset was repeated using the larger UK Biobank database (healthy volunteers), which replicated the findings, reported InfoSalut.

Using these two large and powerful data sets allowed the team to identify the subtle markers, despite the fact that Parkinson’s disease has a relatively low prevalence (0.1-0.2 per cent of the population).

Parkinson’s disease is a progressive neurological condition, characterised by a reduction in dopamine, and post mortem examination of patients with Parkinson’s disease has found differences in the INL (inner nuclear layer) of the retina.

This study confirmed previous reports of significantly reduced thickness of the GCIPL (ganglion cell inner plexiform layer), while for the first time reduced thickness of the INL was observed.

In addition, it found that reduced thickness of these layers was associated with an increased risk of developing Parkinson’s disease, over and above that conferred by other factors or comorbidities.

The authors note that future studies are needed to determine whether the progression of GCIPL atrophy is driven by brain changes in Parkinson’s disease, or whether INL thinning precedes GCIPL atrophy.

Exploring this could help explain the mechanism and determine whether retinal imaging could support the diagnosis, prognosis and complex management of patients affected by Parkinson’s disease.

In contemporary medical practice, high-resolution retinal imaging has seamlessly integrated into routine ophthalmology. A type of 3D scanner known as “optical coherence tomography” (OCT) plays a prominent role, widely employed in ophthalmology and optical clinics.

Remarkably fast, OCT can deliver a cross-sectional view of the retina (the rear of the eye) in under a minute, revealing intricate details down to minuscule measurements of a thousandth of a millimetre.