Abstract
In the last two decades transcranial sonography (TCS) has developed as a valuable, supplementary tool in the diagnosis and differential diagnosis of movement disorders. In this review, we highlight recent evidence supporting TCS as a reliable method in the differential diagnosis of parkinsonism, combining substantia nigra (SN), basal ganglia and ventricular system findings. Moreover, several studies support SN hyperechogenicity as one of most important risk factors for Parkinson’s disease (PD). The advantages of TCS include short investigation time, low cost and lack of radiation. Principal limitations are still the dependency on the bone window and operator experience. New automated algorithms may reduce the role of investigator skill in the assessment and interpretation, increasing TCS diagnostic reliability. Based on the convincing evidence available, the EFNS accredited the method of TCS a level A recommendation for supporting the diagnosis of PD and its differential diagnosis from secondary and atypical parkinsonism. An increasing number of training programmes is extending the use of this technique in clinical practice.
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Acknowledgments
We would like to thank all participants of the studies assessing SN+ in longitudinal cohorts and all the staff members involved in applying and teaching this method at the moment, especially Ina Posner. We would also like to express our gratitude to Georg Becker who was the first to assess and promote TCS in movement disorders.
Andrea Pilotto and his work was supported by a Research-fellowhip program of DAAD (German Academic Exchange Service)
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Rezzak Yilmaz declares no conflict of interest.
Andrea Pilotto has received an honorarium payment from Research-Fellowship Programme of DAAD (German Academic Exchange Service. Rezzak Yilmaz declares no conflict of interest. Daniela Berg has received consultancy fees from UCB, Novartis, Lundbeck, GSK and TEVA, founding from UCB, Novartis, Lundbeck, GSK and TEVA and grant from Michael J. Fox Foundation, BmBF, dPV (German Parkinson’s Disease Association), Center of Integrative Neurosciences, Internationale Parkinson Fonds, Janssen Pharmaceutica, TEVA Pharma GmbH and UCB Pharma GmbH.
Daniela Berg has received consultancy fees from UCB, Novartis, Lundbeck, GSK and TEVA.
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Pilotto, A., Yilmaz, R. & Berg, D. Developments in the Role of Transcranial Sonography for the Differential Diagnosis of Parkinsonism. Curr Neurol Neurosci Rep 15, 43 (2015). https://doi.org/10.1007/s11910-015-0566-9
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DOI: https://doi.org/10.1007/s11910-015-0566-9