title: Substantia nigra hyperechogenicity with LRRK2 G2019S mutations.
abstract: BACKGROUND
  Transcranial sonography (TCS) area of hyperechogenicity in the substantia nigra (aSN) is increased in idiopathic and genetic Parkinson's disease (PD).
  
  
  METHODS
  We performed TCS in 34 LRRK2 G2019S mutation carriers manifesting PD, 24 non-manifesting mutation carriers, and 28 idiopathic PD patients and compared them with 40 healthy controls (total, n = 126).
  
  
  RESULTS
  Compared with the controls (mean 0.15 cm(2) ), the aSN values in all other groups were increased. The mean aSN was 0.23 cm(2) in nonmanifesting mutation carriers (P = .015), 0.34 cm(2) in idiopathic PD patients (P < .0001), 0.32 cm(2) in LRRK2-associated PD patients (P < .0001), and 0.33 cm(2) in the overall PD group (P < .0001). LRRK2-associated PD patients had a higher aSN than did nonmanifesting carriers (P = .011), but there was no significant difference in aSN between patients with idiopathic and LRRK2-associated PD (P = .439).
  
  
  CONCLUSIONS
  Our results suggest that SN pathoanatomical alterations may not be substantially different between idiopathic and LRRK2-associated PD. The findings in the nonmanifesting mutation carriers suggest the presence of intermediate nigrostriatal pathology consistent with the age-dependent reduced penetrance of this mutation.
authors.affiliation: Section of Clinical and Molecular Neurogenetics at the Department of Neurology, University of Lübeck, Lübeck, Germany.
authors.forename: Norbert
authors.initials: N
authors.lastname: Brüggemann
authors.forename: Johann
authors.initials: J
authors.lastname: Hagenah
authors.forename: Kaili
authors.initials: K
authors.lastname: Stanley
authors.forename: Christine
authors.initials: C
authors.lastname: Klein
authors.forename: Cuiling
authors.initials: C
authors.lastname: Wang
authors.forename: Deborah
authors.initials: D
authors.lastname: Raymond
authors.forename: Laurie
authors.initials: L
authors.lastname: Ozelius
authors.forename: Susan
authors.initials: S
authors.lastname: Bressman
authors.forename: Rachel
authors.initials: R
authors.lastname: Saunders-Pullman
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005998:Glycine / Q000235:genetics; D006801:Humans; D000071158:Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D010300:Parkinson Disease / Q000235:genetics* / Q000473:pathology*; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*; D012694:Serine / Q000235:genetics; D013378:Substantia Nigra / Q000000981:diagnostic imaging / Q000473:pathology*; D017585:Ultrasonography, Doppler, Transcranial / Q000379:methods
chemical_list: D012694:Serine; C495280:LRRK2 protein, human; D000071158:Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; D017346:Protein Serine-Threonine Kinases; D005998:Glycine