title: Quantitative simultaneous (99m)Tc-ECD/123I-FP-CIT SPECT in Parkinson's disease and multiple system atrophy.
abstract: OBJECTIVE
  The purpose of this study was to investigate the feasibility and utility of dual-isotope SPECT for differential diagnosis of idiopathic Parkinson's disease (IPD) and multiple system atrophy (MSA).
  
  
  METHODS
  Simultaneous (99m)Tc-ECD/123I-FP-CIT studies were performed in nine normal controls, five IPD patients, and five MSA patients. Projections were corrected for scatter, cross-talk, and high-energy penetration, and iteratively reconstructed while correcting for patient-specific attenuation and variable collimator response. Perfusion and dopamine transporter (DAT) function were assessed using voxel-based statistical parametric mapping (SPM2) and volume of interest quantitation. DAT binding potential (BP) and asymmetry index (AI) were estimated in the putamen and caudate nucleus.
  
  
  RESULTS
  Striatal BP was lower in IPD (55%) and MSA (23%) compared to normal controls (p<0.01) , and in IPD compared to MSA (p<0.05). AI was greater for IPD than for MSA and controls in both the caudate nucleus and the putamen (p<0.05). There was significantly decreased perfusion in the left and right nucleus lentiformis in MSA compared to IPD and controls (p<0.05).
  
  
  CONCLUSIONS
  Dual-isotope studies are both feasible in and promising for the diagnosis of parkinsonian syndromes.
authors.affiliation: Division of Nuclear Medicine, Department of Radiology, Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA. elfakhri@bwh.harvard.edu
authors.forename: Georges
authors.initials: G
authors.lastname: El Fakhri
authors.forename: Marie-Odile
authors.initials: MO
authors.lastname: Habert
authors.forename: Philippe
authors.initials: P
authors.lastname: Maksud
authors.forename: Aurélie
authors.initials: A
authors.lastname: Kas
authors.forename: Zoulikha
authors.initials: Z
authors.lastname: Malek
authors.forename: Marie Foley
authors.initials: MF
authors.lastname: Kijewski
authors.forename: Lucette
authors.initials: L
authors.lastname: Lacomblez
mesh_terms: D003545:Cysteine / Q000031:analogs & derivatives*; D003937:Diagnosis, Differential; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008297:Male; D008875:Middle Aged; D019578:Multiple System Atrophy / Q000000981:diagnostic imaging*; D015609:Organotechnetium Compounds; D010300:Parkinson Disease / Q000000981:diagnostic imaging*; D011877:Radionuclide Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014326:Tropanes
chemical_list: D015609:Organotechnetium Compounds; D014326:Tropanes; C087552:2-carbomethoxy-8-(3-fluoropropyl)-3-(4-iodophenyl)tropane; C059659:technetium Tc 99m bicisate; D003545:Cysteine