Parkinson's disease is often not diagnosed until later stages, when many nerve cells in the brain have already died off, and movement problems have started. This means that many people don't start treatment until the disease is advanced. Better diagnostic tools could help Parkinson's patients get help sooner, which may improve outcomes. Several studies have outlined new diagnostic tools for the neurodegenerative disorder.
Retinal Exam for Dx
A study reported in the Neurobiology of Disease shown that the retinas of Parkinson's disease patients have different responses to light stimuli compared to unaffected individuals.
This small study included 20 people who gotten a Parkinson's diagnosis within the previous 5 years, and a group of healthy volunteers. Electrodes that recorded the retina's response to light flashes were placed on the lower eyelids of study participants. The responses of Parkinson's patients were significantly different from the control group.
The method was repeated in a mouse model of Parkinson's and similar results were obtained. A retinal exam might be useful in the future for early diagnosis, although more testing to confirm these findings will be needed.
A Novel Parkinson's Biomarker
In an unrelated study reported in EMBO Molecular Medicine, researchers have found that a misfolded protein called alpha-synuclein (αSyn) could reveal who is likely to be diagnosed with Parkinson's. Previous work has shown that the a shift in αSyn that makes the protein's structure less like a helix, and more like a sheet, is related to the development of Parkinson's.
These misfolded proteins get sticky, and start to form clumps and structures known as Lewy bodies.
This study has shown that misfolded αSyn can act as a biomarker of Parkinson's disease. They analyzed cerebrospinal fluid samples from 134 people, and the biomarker accurately diagnosed Parkinson's 90% of the time.
While additional confirmation will be needed before this assay can be brought to the clinic, it presents another potential option for earlier Parkinson's diagnosis and treatment.
A Method for Monitoring Symptoms in Patients
Scientists have also developed a video tool that can be used to monitor the progression of symptoms in patients with movement disorders like Parkinson's. This technique is called VisionMD, and it is meant to reveal subtle changes in movement.
Since different clinicians could have different interpretations of how movement in a patient is changing, this method offers a way to standardize assessments. The tool also analyzes a patient's movements and interprets them rapidly, so clinicians don't have to spend a lot of time watching the videos themselves.
This open source tool has been described in a recent report in npj Parkinson's Disease. Since VisionMD is already in use in a few countries such as Spain, Germany, and Italy, it may be coming soon to a clinic near you.
Sources: Neurobiology of Disease, EMBO Molecular Medicine, npj Parkinson's Disease
