title: Transcranial sonography of the substantia nigra and its correlation with DAT-SPECT in the diagnosis of Parkinson's disease.
abstract: BACKGROUND
  Transcranial sonography (TCS) of the substantia nigra is a new and promising method to diagnose Parkinson's disease (PD) but its effectiveness is controversial.
  
  
  METHODS
  All 55 PD patients involved in the study underwent single photon emission computed tomography (SPECT) imaging using the labeled dopamine transporter radiotracer (99m)Tc-TRODAT-1 to assess nigrostriatal dopaminergic function. The echogenicity of the substantia nigra was measured by TCS in all patients who received DAT-SPECT scanning. Finally, statistical analysis was carried out to determine the diagnostic accuracy of TCS as well as its correlation with (99m)Tc-TRODAT-1 SPECT, its positive predictive value (PPV), and negative predictive value (NPV).
  
  
  RESULTS
  Contralateral striatal (99m)Tc-TRODAT-1 uptake was significantly reduced compared to ipsilateral striatal uptake, and had a negative correlation with UPDRS-Ⅲ(r = -0.334, p = 0.013), disease duration (r = -0.393, p = 0.003) and H-Y stage (r = -0.330, p = 0.014). After TCS measurement, the contralateral SN echogenic area was similar to the ipsilateral SN echogenic area (27.77 ± 13.19 vs 25.98 ± 11.94 mm(2), p = 0.402, n = 24). No correlation was identified between TCS and UPDRS-Ⅲ (r = 0.383, p = 0.065), disease duration (r = 0.371, p = 0.075) or H-Y stage (r = 0.259, p = 0.222). The sensitivity and specificity of SN TCS for the diagnosis of PD were calculated as 64.70% and 60% according to DAT-SPECT, respectively, while the positive predictive value and negative predictive value was calculated as 91.67% and 20%, respectively.
  
  
  CONCLUSIONS
  Compared to DAT-SPECT, TCS is a non-radioactive and convenient procedure to perform. In our investigation, TCS had no correlation with DAT-SPECT. However, the high positive predictive value of TCS highlights its possible utility as a routine diagnostic test.
authors.affiliation: Department of Neurology & Institute of Neurology, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
authors.forename: Dun-hui
authors.initials: DH
authors.lastname: Li
authors.affiliation: Department of Neurology & Institute of Neurology, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
authors.forename: Lin-yuan
authors.initials: LY
authors.lastname: Zhang
authors.affiliation: Department of Ultrasound, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
authors.forename: Yun-yun
authors.initials: YY
authors.lastname: Hu
authors.affiliation: Department of Nuclear Medicine, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
authors.forename: Xu-feng
authors.initials: XF
authors.lastname: Jiang
authors.affiliation: Department of Neurology & Institute of Neurology, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
authors.forename: Hai-yan
authors.initials: HY
authors.lastname: Zhou
authors.affiliation: Department of Neurology & Institute of Neurology, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
authors.forename: Qiong
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Department of Neurology & Institute of Neurology, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
authors.forename: Wen-yan
authors.initials: WY
authors.lastname: Kang
authors.affiliation: Department of Neurology & Institute of Neurology, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China. Electronic address: jly0520@hotmail.com.
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Neurology & Institute of Neurology, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China. Electronic address: chen_sd@medmail.com.cn.
authors.forename: Sheng-Di
authors.initials: SD
authors.lastname: Chen
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015609:Organotechnetium Compounds; D010300:Parkinson Disease / Q000175:diagnosis* / Q000000981:diagnostic imaging; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals; D013378:Substantia Nigra / Q000000981:diagnostic imaging*; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D014326:Tropanes; D017585:Ultrasonography, Doppler, Transcranial / Q000379:methods*
chemical_list: D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D014326:Tropanes; C104196:technetium Tc 99m TRODAT-1
keywords: Echogenicity; Parkinson's disease; SPECT; Transcranial sonography