title: Quantification of Parkinson's disease-related network expression with ECD SPECT.
abstract: OBJECTIVE
  Spatial covariance analysis has been used with FDG PET to identify a specific metabolic network associated with Parkinson's disease (PD). In the current study, we utilized a new, fully automated voxel-based method to quantify network expression in ECD SPECT images from patients with classical PD, patients with multiple system atrophy (MSA), and healthy control subjects.
  
  
  METHODS
  We applied a previously validated voxel-based PD-related covariance pattern (PDRP) to quantify network expression in the ECD SPECT scans of 35 PD patients, 15 age- and disease severity-matched MSA patients, and 35 age-matched healthy control subjects. PDRP scores were compared across groups using analysis of variance. The sensitivity and specificity of the prospectively computed PDRP scores in the differential diagnosis of individual subjects were assessed by receiver operating characteristic (ROC) analysis.
  
  
  RESULTS
  PDRP scores were significantly increased (p < 0.001) in the PD group relative to the MSA and control groups. ROC analysis indicated that the overall diagnostic accuracy of the PDRP measures was 0.91 (AUC). The optimal cutoff value was consistent with a sensitivity of 0.97 and a specificity of 0.80 and 0.71 for discriminating PD patients from MSA and normal controls, respectively.
  
  
  CONCLUSIONS
  Our findings suggest that fully automated voxel-based network assessment techniques can be used to quantify network expression in the ECD SPECT scans of parkinsonian patients.
authors.affiliation: Center for Neurosciences, The Feinstein Institute for Medical Research, North Shore-LIJ Health System, 350 Community Drive, Manhasset, NY 11030, USA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Eckert
authors.forename: Koen
authors.initials: K
authors.lastname: Van Laere
authors.forename: Chengke
authors.initials: C
authors.lastname: Tang
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Lewis
authors.forename: Christine
authors.initials: C
authors.lastname: Edwards
authors.forename: Patrick
authors.initials: P
authors.lastname: Santens
authors.forename: David
authors.initials: D
authors.lastname: Eidelberg
mesh_terms: D000465:Algorithms; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism; D003545:Cysteine / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008875:Middle Aged; D019578:Multiple System Atrophy / Q000000981:diagnostic imaging / Q000378:metabolism; D015609:Organotechnetium Compounds / Q000493:pharmacokinetics; D010300:Parkinson Disease / Q000000981:diagnostic imaging* / Q000378:metabolism; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D015398:Signal Transduction; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
chemical_list: D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C059659:technetium Tc 99m bicisate; D003545:Cysteine