title: Is transcranial sonography useful to distinguish scans without evidence of dopaminergic deficit patients from Parkinson's disease?
abstract: BACKGROUND
  Approximately 10% of patients clinically diagnosed with early Parkinson's disease (PD) subsequently have normal dopaminergic functional imaging. Transcranial sonography (TCS) has been shown to detect midbrain hyperechogenicity in approximately 90% of Parkinson's disease (PD) patients and 10% of the healthy population. The aim of this study was to investigate the prevalence of midbrain hyperechogenicity in patients with suspected parkinsonism and scans without evidence of dopaminergic deficit (SWEDD), in comparison to PD patients.
  
  
  METHODS
  TCS was performed in 14 patients with SWEDD and 19 PD patients.
  
  
  RESULTS
  There was a significantly increased area of echogenicity in the PD group (0.24 ± 0.06 cm(2) ), compared to the group of patients with SWEDD (0.13 ± 0.06 cm(2) ; P < 0.001). One (9.1%) of these patients, compared to 14 (82.5%) of the PD patients, was found to have hyperechogenicity (P < 0.001).
  
  
  CONCLUSIONS
  We conclude that TCS is useful to distinguish PD patients from patients with suspected parkinsonism and SWEDD.
authors: Department of Neurology, Medical University Innsbruck, Innsbruck, Austria. heike.stockner@i-med.ac.at
authors: Heike
authors: H
authors: Stockner
authors: Petra
authors: P
authors: Schwingenschuh
authors: Atbin
authors: A
authors: Djamshidian
authors: Laura
authors: L
authors: Silveira-Moriyama
authors: Petra
authors: P
authors: Katschnig
authors: Klaus
authors: K
authors: Seppi
authors: John
authors: J
authors: Dickson
authors: Mark J
authors: MJ
authors: Edwards
authors: Andrew J
authors: AJ
authors: Lees
authors: Werner
authors: W
authors: Poewe
authors: Kailash P
authors: KP
authors: Bhatia
mesh_terms: D000368:Aged; D003072:Cognition Disorders / Q000150:complications; D003937:Diagnosis, Differential; D004298:Dopamine / Q000378:metabolism*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008636:Mesencephalon / Q000000981:diagnostic imaging; D008875:Middle Aged; D009413:Nerve Fibers, Myelinated; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D049268:Positron-Emission Tomography; D013701:Temporal Bone / Q000000981:diagnostic imaging; D017585:Ultrasonography, Doppler, Transcranial / Q000379:methods*
chemical_list: D004298:Dopamine