5-minute Fellowships: Dr Alexis Cheviet – A simple diagnostic test to differentiate PSP from Parkinson’s

Progressive Supranuclear Palsy (PSP) is an atypical form of Parkinson’s, sharing many symptoms of the typical form of the disease. People with PSP, however, also have a progressive inability to control their eye movement along the vertical axis. With so many shared symptoms, around 50% of PSP cases are mistaken for Parkinson’s. This puts people with PSP at a disadvantage because their symptoms are less likely to be alleviated by Parkinson’s medication. 

In his project, Alexis found that people with PSP have different visual attention – both reflexive and voluntary – to those with Parkinson’s, especially on the vertical axis. From this, he has designed a short diagnostic test based on the Bell’s Cancellation Task which asks people to circle all the bell images they find among 280 distractions. Because people with PSP have difficulty controlling their eye movements up and down, if a person circles the bell images in an unorganised and slower time, it gives clinicians greater confidence that there should be a diagnosis of PSP versus Parkinson’s.