title: Echogenic substantia nigra in patients with orthostatic tremor.
abstract: OBJECTIVE
  Previous studies suggest that the nigrostriatal dopaminergic transmission is impaired in patients with primary orthostatic tremor.
  
  
  METHODS
  We used transcranial sonography (TCS) to examine the morphology of the substantia nigra (SN) in four patients with primary orthostatic tremor (OT).
  
  
  RESULTS
  TCS revealed an SN echogenicity in all patients, in three patients unilaterally, in one patient bilaterally.
  
  
  CONCLUSIONS
  Our data suggest nigrostriatal dopaminergic deficits in OT patients. The exact impact of these dopaminergic deficits on OT generation is unclear.
authors.affiliation: Department of Neurology, University of the Saarland, Homburg, Saar, Germany. nejspi@uniklinik-saarland.de
authors.forename: J
authors.initials: J
authors.lastname: Spiegel
authors.forename: S
authors.initials: S
authors.lastname: Behnke
authors.forename: G
authors.initials: G
authors.lastname: Fuss
authors.forename: G
authors.initials: G
authors.lastname: Becker
authors.forename: U
authors.initials: U
authors.lastname: Dillmann
mesh_terms: D000368:Aged; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology; D013378:Substantia Nigra / Q000473:pathology*; D014202:Tremor / Q000473:pathology*; D017585:Ultrasonography, Doppler, Transcranial