title: Substantia nigra hyperechogenicity does not correlate with motor features in Parkinson's disease.
abstract: BACKGROUND
  The evaluation of hyperechogenicity of the substantia nigra (SN) by transcranial sonography (TCS) is validated for the diagnosis of Parkinson's disease (PD). However, its correlation with the severity of motor involvement is still uncertain.
  
  
  METHODS
  We included patients with clinical diagnosis of idiopathic PD in a cross-sectional study. All patients were evaluated with Unified Parkinson's Disease Rating Scale-motor score (UPDRS-III) and TCS at the same day with measurement of the area of SN hyperechogenicity for each side. We analysed the association between the area of SN hyperechogenicity and the contralateral motor scores of UPDRS-III, adjusting for age and dominance of the patient (statistical significance set to p<0.05).
  
  
  RESULTS
  35 patients were analysed, 3 (8.6%) were excluded due to poor temporal acoustic bone window. From a total of 32 patients, the mean age was 58.4 (±11.2)years. The mean area of SN hyperechogenicity was: right 0.26 (±0.12)cm(2) and left 0.27 (±0.07)cm(2). The mean score of UPDRS-III was 18.9 (±6.1). There were no statistically significant association between the scores of the UPDRS-III (rigidity, tremor and bradykinesia) and the contralateral area of SN hyperechogenicity.
  
  
  CONCLUSIONS
  The area of SN hyperechogenicity did not correlate with motor deterioration in Parkinson's disease.
authors.affiliation: Neurology Department, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal. Electronic address: joanajribeiro@gmail.com.
authors.forename: Joana
authors.initials: J
authors.lastname: Jesus-Ribeiro
authors.affiliation: Neurology Department, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal; Neurosonology Laboratory, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.
authors.forename: João
authors.initials: J
authors.lastname: Sargento-Freitas
authors.affiliation: Neurology Department, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.
authors.forename: Mário
authors.initials: M
authors.lastname: Sousa
authors.affiliation: Neurology Department, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal; Neurosonology Laboratory, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.
authors.forename: Fernando
authors.initials: F
authors.lastname: Silva
authors.affiliation: Neurology Department, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal; Faculdade de Medicina, Universidade de Coimbra, Coimbra, Portugal.
authors.forename: António
authors.initials: A
authors.lastname: Freire
authors.affiliation: Neurology Department, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal; Faculdade de Medicina, Universidade de Coimbra, Coimbra, Portugal.
authors.forename: Cristina
authors.initials: C
authors.lastname: Januário
mesh_terms: D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology; D009127:Muscle Rigidity / Q000209:etiology*; D010300:Parkinson Disease / Q000150:complications* / Q000473:pathology*; D012720:Severity of Illness Index; D013378:Substantia Nigra / Q000000981:diagnostic imaging*; D014202:Tremor / Q000209:etiology*; D017585:Ultrasonography, Doppler, Transcranial
keywords: Parkinson's disease; Substantia nigra; UPDRS; Ultrasound