title: Transcranial sonography on Parkinson's disease and essential tremor.
abstract: BACKGROUND
  The study on transcranial sonocraphy (TCS) as a diagnostic test for Parkinson's disease (PD) has been neglected in some hospitals. The current study was conducted as the first study to investigate the utility of TCS for diagnosis of PD and its ability to distinguish PD from essential tremor (ET) in an Iranian population.
  
  
  METHODS
  TCS of substantia nigra (SN) was performed on 50 PD, 48 ET, and 50 healthy controls by two blinded investigators.
  
  
  RESULTS
  Bilateral SN margin over 0.20 cm(2) was found in 39 (90%) and 7 (15%) in PD and ET patients, respectively. Furthermore, 4 (8%) of healthy control displayed this particular echo feature as well (false positives). SN hyperechogenicity ≥0.20 cm(2) was considered as a cut-off point to detected PD. Accordingly, TCS proved 90% (95% confidence interval [CI]: 77.85-97.35) sensitive and 92% (95% CI: 80.75-97.73)specific for the detection of PD by visualizing the SN.
  
  
  CONCLUSIONS
  SN hyperechogenicity ≥20 cm(2) is a specific feature of PD. Since, the symptoms of PD and ET might be overlapping; this method seems to be reliable to confirm PD diagnosis in doubtful clinical cases. Further studies in years to come are warranted to shed light on standardized data for Iranian to enhance the validity of TCS.
authors: Isfahan Neuroscience Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
authors: Ahmad
authors: A
authors: Chitsaz
authors: Noushin
authors: N
authors: Mehrbod
authors: Mohammad
authors: M
authors: Saadatnia
authors: Mahboobeh
authors: M
authors: Fereidan-Esfahani
authors: Mojtaba
authors: M
authors: Akbari
authors: Seyed-Hossein
authors: SH
authors: Abtahi
keywords: Essential tremor; Parkinson; transcranial sonography
references: Mov Disord. 2007 Feb 15;22(3):414-7
references: 17226854
references: Neurol Sci. 2012 Oct;33(5):1005-9
references: 22160731
references: Ultrasound Med Biol. 2007 Jan;33(1):15-25
references: 17189043
references: Arch Neurol. 1998 Jun;55(6):823-8
references: 9626774
references: Neurology. 2000 Feb 8;54(3):697-702
references: 10680806
references: Nucl Med Commun. 2008 Mar;29(3):193-207
references: 18349789
references: Eur J Neurol. 2002 Nov;9 Suppl 3:23-30
references: 12464118
references: Acta Neurol Scand. 2009 Jan;119(1):17-21
references: 18549415
references: Mov Disord. 2007 Aug 15;22(11):1607-14
references: 17546668
references: Ann Neurol. 1986 Dec;20(6):744-7
references: 3813504
references: Mov Disord. 2007 Jul 30;22(10):1402-1407
references: 17516475
references: Neurology. 1995 Jan;45(1):182-4
references: 7824114
references: Arch Neurol. 1999 Jan;56(1):33-9
references: 9923759
references: Ann Neurol. 1994 Oct;36(4):636-42
references: 7944296
references: J Neurol. 2001 Aug;248(8):684-9
references: 11569897
references: Neurology. 2003 Jan 14;60(1):74-7
references: 12525721
references: Neurology. 1995 Jun;45(6):1138-43
references: 7783878
references: J Neurol Neurosurg Psychiatry. 2008 Apr;79(4):368-76
references: 18344392
references: J Neurol Neurosurg Psychiatry. 1992 Mar;55(3):181-4
references: 1564476
references: J Neurol. 2009 Apr;256(4):530-8
references: 19224315
references: Neurodegener Dis. 2010;7(5):284-90
references: 20616563
references: Lancet Neurol. 2008 Nov;7(11):1044-55
references: 18940694