title: Machine learning models for the differential diagnosis of vascular parkinsonism and Parkinson's disease using [(123)I]FP-CIT SPECT.
abstract: OBJECTIVE
  The study's objective was to develop diagnostic predictive models using data from two commonly used [(123)I]FP-CIT SPECT assessment methods: region-of-interest (ROI) analysis and whole-brain voxel-based analysis.
  
  
  METHODS
  We included retrospectively 80 patients with vascular parkinsonism (VP) and 164 patients with Parkinson's disease (PD) who underwent [(123)I]FP-CIT SPECT. Nuclear-medicine specialists evaluated the scans and calculated bilateral caudate and putamen [(123)I]FP-CIT uptake and asymmetry indices using BRASS software. Statistical parametric mapping (SPM) was used to compare the radioligand uptake between the two diseases at the voxel level. Quantitative data from these two methods, together with potential confounding factors for dopamine transporter availability (sex, age, disease duration and severity), were used to build predictive models following a tenfold cross-validation scheme. The performance of logistic regression (LR), linear discriminant analysis and support vector machine (SVM) algorithms for ROI data, and their penalized versions for SPM data (penalized LR, penalized discriminant analysis and SVM), were assessed.
  
  
  RESULTS
  Significant differences were found in the ROI analysis after covariate correction between VP and PD patients in [(123)I]FP-CIT uptake in the more affected side of the putamen and the ipsilateral caudate. Age, disease duration and severity were also found to be informative in feeding the statistical model. SPM localized significant reductions in [(123)I]FP-CIT uptake in PD with respect to VP in two specular clusters comprising areas corresponding to the left and right striatum. The diagnostic predictive accuracy of the LR model using ROI data was 90.3 % and of the SVM model using SPM data was 90.4 %.
  
  
  CONCLUSIONS
  The predictive models built with ROI data and SPM data from [(123)I]FP-CIT SPECT provide great discrimination accuracy between VP and PD. External validation of these methods is necessary to confirm their applicability across centres.
authors.affiliation: Unidad de Trastornos del Movimiento, Servicio de Neurología y Neurofisiología Clínica, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Avda. Manuel Siurot s/n., 41013, Seville, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Huertas-Fernández
authors.forename: F J
authors.initials: FJ
authors.lastname: García-Gómez
authors.forename: D
authors.initials: D
authors.lastname: García-Solís
authors.forename: S
authors.initials: S
authors.lastname: Benítez-Rivero
authors.forename: V A
authors.initials: VA
authors.lastname: Marín-Oyaga
authors.forename: S
authors.initials: S
authors.lastname: Jesús
authors.forename: M T
authors.initials: MT
authors.lastname: Cáceres-Redondo
authors.forename: J A
authors.initials: JA
authors.lastname: Lojo
authors.forename: J F
authors.initials: JF
authors.lastname: Martín-Rodríguez
authors.forename: F
authors.initials: F
authors.lastname: Carrillo
authors.forename: P
authors.initials: P
authors.lastname: Mir
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001185:Artificial Intelligence; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008297:Male; D010300:Parkinson Disease / Q000000981:diagnostic imaging*; D010302:Parkinson Disease, Secondary / Q000000981:diagnostic imaging*; D019275:Radiopharmaceuticals; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D014326:Tropanes
chemical_list: D019275:Radiopharmaceuticals; D014326:Tropanes; C087552:2-carbomethoxy-8-(3-fluoropropyl)-3-(4-iodophenyl)tropane