title: Reduced thalamic volume in Parkinson disease with REM sleep behavior disorder: volumetric study.
abstract: BACKGROUND
  REM sleep behavior disorder (RBD) is a common non motor feature of Parkinson's Disease (PD) affecting about half the patients with this disease. Distinct structural brain tissue abnormalities have been reported in several regions modulating REM sleep of the patients with idiopathic RBD. At the present time, there are no conventional MRI studies investigating patients with PD associated with RBD.
  
  
  METHODS
  Herein, we used voxel-based morphometry (VBM) to detect the neuroanatomical profile of PD patients with and without RBD. Optimized VBM was applied to the MRI brain images in 11 PD patients with RBD (PD-RBD), 11 PD patients without RBD (PD) and 18 age-and sex-matched controls. To corroborate VBM findings we used automated volumetric method (FreeSurfer) to quantify subcortical brain regions volumes. Patients and controls also underwent DAT-SPECT and cardiac MIBG scintigraphies.
  
  
  RESULTS
  The VBM analysis showed markedly reduced gray matter volume in the right thalamus of PD-RBD patients in comparison with PD patients and controls. Automatic thalamic segmentation in PD-RBD patients showed a bilaterally reduced thalamic volume as compared with PD patients or controls. All PD patients (with and without RBD) showed a reduced tracer uptake on DAT-SPECT and cardiac MIBG scintigraphies as compared to controls.
  
  
  CONCLUSIONS
  Our findings suggest that the presence of RBD symptoms in PD patients is associated with a reduced thalamic volume suggesting a pathophysiologic role of the thalamus in the complex circuit causing RBD.
authors.affiliation: Neuroimaging Research Unit, National Research Council, Catanzaro, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Salsone
authors.affiliation: Neuroimaging Research Unit, Institute of Bioimaging and Molecular Physiology, National Research Council, Germaneto, Catanzaro, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Cerasa
authors.affiliation: Institute of Neurology, Department of Medical Sciences, University Magna Graecia, Germaneto, Catanzaro, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Arabia
authors.affiliation: Institute of Neurology, Department of Medical Sciences, University Magna Graecia, Germaneto, Catanzaro, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Morelli
authors.affiliation: Institute of Neurology, Department of Medical Sciences, University Magna Graecia, Germaneto, Catanzaro, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Gambardella
authors.affiliation: Institute of Neurology, Department of Medical Sciences, University Magna Graecia, Germaneto, Catanzaro, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Mumoli
authors.affiliation: Neuroimaging Research Unit, Institute of Bioimaging and Molecular Physiology, National Research Council, Germaneto, Catanzaro, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Nisticò
authors.affiliation: Neuroimaging Research Unit, Institute of Bioimaging and Molecular Physiology, National Research Council, Germaneto, Catanzaro, Italy.
authors.forename: B
authors.initials: B
authors.lastname: Vescio
authors.affiliation: Institute of Neurology, Department of Medical Sciences, University Magna Graecia, Germaneto, Catanzaro, Italy; Neuroimaging Research Unit, Institute of Bioimaging and Molecular Physiology, National Research Council, Germaneto, Catanzaro, Italy. Electronic address: quattrone@unicz.it.
authors.forename: A
authors.initials: A
authors.lastname: Quattrone
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000150:complications / Q000473:pathology*; D020187:REM Sleep Behavior Disorder / Q000209:etiology / Q000473:pathology*; D012895:Sleep, REM / Q000502:physiology*; D013788:Thalamus / Q000473:pathology*
keywords: Automated segmentation method; Parkinson disease; REM sleep behavior disorder; Resonance imaging; Voxel-based morphometry