A brain image detail has been identified as a new accurate test for Parkinson’s disease by researchers at The University of Nottingham.
The image, shaped similar to a Swallow’s tail show up in the healthy state of a group of cells in the sub-region of the human brain. It was pinpointed with 3T MRI scanning technology, which is standard equipment in clinical settings.
Until now diagnosis of Parkinson’s in clinically undecided cases has been restricted to expensive nuclear medicine methods. The diagnosis can be taxing early in the course of the condition and in tremor dominant cases.
Other non-licensed diagnostic techniques offer a varying range of accuracy, repeatability and reliability. But none of them have demonstrated the needed accuracy and ease of use for application to standard clinical practice.
High Resolution Magnetic Resonance Imaging
Parkinson’s disease is a progressive neurodegenerative disorder which destroys brain cells that control movement. Currently there is no cure but medication and treatments can be given to manage the symptoms.
Employing high resolution, ultra high filed 7-Tesla magnetic resonance imaging, Nottingham’s researchers have previously singled out the characteristic pathology of Parkinson’s with structural change in a small area of the mid brain known as the substantia nigra.
This latest study has shown that these changes can also be detected using less advanced 3T MRI technology which is accessible in hospitals across the country.
They later coined the phrase the ‘swallow tail appearance’ as an easy recognizable sign of the healthy appearing substantia nigra which is lost in Parkinson’s disease. A total of 114 high-resolution scans were reviewed and in 94 per cent of cases the diagnosis was accurately made using this technique.
“This is a breakthrough finding as currently Parkinson’s disease is mostly diagnosed by identifying symptoms like stiffness and tremor”, said team leader Dr Stefan Schwarz. “Imaging tests to confirm the diagnosis are limited to expensive nuclear medical techniques which are not widely available and associated with potentially harmful ionizing radiation. Using Magnetic Resonance Imaging (no ionizing radiation involved and much cheaper than nuclear medical techniques) we identified a specific imaging feature which has great similarity to a tail of a swallow and therefore decided to call it the ‘swallow tail sign’. This sign is absent in Parkinson’s disease.”
Reference: Stefan T. Schwarz, Mohammed Afzal, Paul S. Morgan, Nin Bajaj, Penny A. Gowland, Dorothee P. Auer. The ‘Swallow Tail’ Appearance of the Healthy Nigrosome – A New Accurate Test of Parkinson’s Disease: A Case-Control and Retrospective Cross-Sectional MRI Study at 3T. PLoS ONE, 2014; 9 (4): e93814 DOI: 10.1371/journal.pone.0093814
Image of scan courtesy of Dr Stefan Schwarz, Swallow images courtesy of the RSPB. Creative Commons License