title: Dopaminergic denervation is not necessary to induce gait disorders in atypical parkinsonian syndrome.
abstract: BACKGROUND
  Gait impairment is common in parkinsonian syndromes but not specific to striatonigral dysfunction. The relationship between the dopaminergic system and gait parameters is poorly understood. This cross-sectional study aimed to determine if gait measures are related to the striatal dopamine transporters distribution using [(123)I]FP-CIT SPECT in patients with parkinsonian syndromes.
  
  
  METHODS
  Twenty-four patients with gait impairment and parkinsonian syndromes without Parkinson's disease (mean age: 73.6±8.2years) were included in this study. Gait analysis during single- and dual-task condition (walking and backwards counting) and [(123)I]FP-CIT SPECT were performed within 3months of each other. Patients were visually categorized as having normal (n=14) or abnormal (n=10) [(123)I]FP-CIT SPECT. In addition, a volume-of-interest-based analysis of uptake ratios (caudate and putamen) relative to the occipital cortex and a voxelwise analysis using SPM8 were also performed.
  
  
  RESULTS
  Patients with parkinsonian syndromes and abnormal [(123)I]FP-CIT SPECT did not significantly differ in terms of spatiotemporal gait parameters from those with normal [(123)I]FP-CIT SPECT. Moreover, after correction for multiple comparisons, we did not observe any association between regional uptake ratio and spatiotemporal gait parameters for single and dual tasking. Finally, none of these parameters showed a significant association with voxelwise [(123)I]FP-CIT uptake.
  
  
  CONCLUSIONS
  Dopaminergic denervation, as measured by [(123)I]FP-CIT SPECT, is not necessary to induce alterations of spatiotemporal gait parameters during single and dual task in patients presenting with atypical parkinsonian syndromes.
authors.affiliation: Division of Neurology, Department of Clinical Neurosciences, Geneva University Hospitals and University of Geneva, Switzerland; Division of Cognitive and Motor Aging, Department of Neurology, Albert Einstein College of Medicine, Yeshiva University, Bronx, NY, USA. Electronic address: gilles.allali@hcuge.ch.
authors.forename: Gilles
authors.initials: G
authors.lastname: Allali
authors.affiliation: Division of Nuclear Medicine and Molecular Imaging, Department of Medical Imaging and Information Sciences, Geneva University Hospitals and University of Geneva, Switzerland. Electronic address: valentina.garibotto@hcuge.ch.
authors.forename: Valentina
authors.initials: V
authors.lastname: Garibotto
authors.affiliation: Division of Nuclear Medicine and Molecular Imaging, Department of Medical Imaging and Information Sciences, Geneva University Hospitals and University of Geneva, Switzerland. Electronic address: isminicharis.mainta@hcuge.ch.
authors.forename: Ismini C
authors.initials: IC
authors.lastname: Mainta
authors.affiliation: Willy Taillard Laboratory of Kinesiology, Geneva University Hospitals and University of Geneva, Switzerland. Electronic address: stephane.armand@hcuge.ch.
authors.forename: Stephane
authors.initials: S
authors.lastname: Armand
authors.affiliation: Division of Neurology, University of Alberta, Edmonton, Canada. Electronic address: richard.camicioli@ualberta.ca.
authors.forename: Richard
authors.initials: R
authors.lastname: Camicioli
authors.affiliation: Division of Nuclear Medicine and Molecular Imaging, Department of Medical Imaging and Information Sciences, Geneva University Hospitals and University of Geneva, Switzerland. Electronic address: osman.ratib@hcuge.ch.
authors.forename: Osman
authors.initials: O
authors.lastname: Ratib
authors.affiliation: Division of Nuclear Medicine and Molecular Imaging, Department of Medical Imaging and Information Sciences, Geneva University Hospitals and University of Geneva, Switzerland. Electronic address: habib.zaidi@hcuge.ch.
authors.forename: Habib
authors.initials: H
authors.lastname: Zaidi
authors.affiliation: Department of Internal Medicine, Rehabilitation and Geriatrics, Geneva University Hospitals and University of Geneva, Switzerland. Electronic address: francois.herrmann@hcuge.ch.
authors.forename: Francois R
authors.initials: FR
authors.lastname: Herrmann
authors.affiliation: Division of Neurology, Department of Clinical Neurosciences, Geneva University Hospitals and University of Geneva, Switzerland. Electronic address: frederic.assal@hcuge.ch.
authors.forename: Frederic
authors.initials: F
authors.lastname: Assal
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D059290:Dopaminergic Neurons / Q000000981:diagnostic imaging*; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017072:Neostriatum / Q000000981:diagnostic imaging*; D020734:Parkinsonian Disorders / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D013378:Substantia Nigra / Q000000981:diagnostic imaging*; D015899:Tomography, Emission-Computed, Single-Photon
keywords: Dual task; Gait disorders; Neuroimaging; Nigrostriatal pathways; Parkinsonian syndromes; [(123)I]FP-CIT SPECT