A new study by the American Academy of Neurology, and supported by the Seoul Metropolitan Government – Seoul National University Boramae Medical Center and the Korean Ministry of Education, Science and Technology, reports that the thinning of retina of our eyes is linked to early Parkinson’s disease. The study was published recently in online issue of Neurology®, the medical journal of the American Academy of Neurology.
“Our study is the first to show a link between the thinning of the retina and a known sign of the progression of the disease — the loss of brain cells that produce dopamine,” said Jee-Young Lee, study author, from the Seoul Metropolitan Government – Seoul National University Boramae Medical Center in South Korea. “We also found the thinner the retina, the greater the severity of disease. These discoveries may mean that neurologists may eventually be able to use a simple eye scan to detect Parkinson’s disease in its earliest stages, before problems with movement begin.”
For the study, the research team worked with 49 people with the average age of all of the participants who were diagnosed with Parkinson’s disease two years earlier but hadn’t yet started medication being 69. The data obtrained from these participants was than compared with that of 54 people of the same age but without Parkinson’s.
Each participant was asked to undergo a complete eye exam as well as high-resolution eye scans. These eye scans use light waves to take high resolution pictures of each layer of the retina. 28 out of the 49 participants with Parkinson’s also went through dopamine transporter positron emission tomography (PET) imaging so that scientists could determine the density of dopamine-producing cells in the brain.
Results of the study indicated that the thinning of retina, especially that of the two inner layers of the five total layers, was strongly evident in those suffering from Parkinson’s. Not just that, it also corresponds to the loss of dopamine-producing brain cells.
“Larger studies are needed to confirm our findings and to determine just why retina thinning and the loss of dopamine-producing cells are linked,” added Lee. “If confirmed, retina scans may not only allow earlier treatment of Parkinson’s disease but more precise monitoring of treatments that could slow progression of the disease as well.”
The research team notes that a limitation of this research is how the retina scans focused only on a limited area of the retina. The study was done quickly and also did not follow participants over a long period of time.