Shared from parkinsonsnewstoday.com.
Parkinson’s disease is a neurodegenerative disorder caused by the dysfunction and death of brain cells that are responsible for making the chemical messenger dopamine. Parkinson’s is marked by motor symptoms such as slowed movement, tremor, stiffness, and balance issues. Most people with Parkinson’s have idiopathic disease, meaning the underlying cause is not known.
Secondary parkinsonism refers to health conditions that can cause Parkinson’s-like motor symptoms, but are not actually Parkinson’s disease. Secondary parkinsonism can develop due to drugs or toxins, or because of problems with blood flow or fluid pressure in and around the brain. Since secondary parkinsonism is by definition characterized by symptoms that are similar to Parkinson’s disease, it can be difficult for clinicians to tell the two apart.
Parkinson’s disease can cause abnormalities in the nerves that connect the eyes to the brain, which are generally less affected in secondary parkinsonism. These nerves can be visualized using a technique called corneal confocal microscopy, or CCM. In this study, scientists in China tested whether CCM might be used to reliably distinguish between true Parkinson’s disease and secondary parkinsonism.