Transcranial brain parenchyma sonography in movement disorders: state of the art

The present paper summarizes recommendations on transcranial sonography (TCS) application in neurodegenerative diseases, resulting from a consensus meeting of the European Society of Neurosonology and Cerebral Hemodynamics. TCS of distinct infra- and supratentorial brain structures detects characteristic changes in several movement disorders, such as abnormal hyperechogenicity of substantia nigra (SN) in Parkinson's disease and of lenticular nucleus in dystonia, Wilson's disease and atypical Parkinsonian disorders. In healthy adults, the TCS finding of marked SN hyperechogenicity indicates a subclinical functional impairment of the nigrostriatal dopaminergic system. The finding of marked SN hyperechogenicity in combination with normal lenticular-nucleus echogenicity discriminates idiopathic Parkinson's disease from multiple-system atrophy and progressive supranuclear palsy with a positive predictive value of more than 90%. As TCS is a quick and noninvasive method, using the same duplex-ultrasound machines as for investigation of intracranial vessels, applicable even in agitated patients, this method has a great potential to be more widely used.