title: Evaluation of brain iron content in idiopathic REM sleep behavior disorder using quantitative magnetic resonance imaging.
abstract: BACKGROUND
  Neuroimaging studies in patients with idiopathic rapid eye movement sleep behavior disorder (iRBD) show similar structural and functional changes to alpha-synucleinopathies, including PD. Until now, there have been few attempts to characterize brain iron deposition in iRBD. The aim of this study was to investigate brain iron content in patients with iRBD using quantitative magnetic resonance imaging (MRI).
  
  
  METHODS
  3-T MRI was performed in 15 patients with iRBD and 20 age-matched healthy control subjects. In order to evaluate the iron-related neurodegenerative changes, we assessed volume and transverse relaxation rate (R2*) simultaneously. We used both region-based and voxel-based analysis.
  
  
  RESULTS
  No significant differences in R2* values were found between iRBD groups and healthy control subjects. There were no areas of significantly reduced or increased gray matter and white matter volume in the iRBD group. Instead, lateral ventricle volumes measured automatically by FreeSurfer were significantly larger in patients with iRBD than in healthy controls (P < 0.05).
  
  
  CONCLUSIONS
  The present study suggests that iron-related R2* values may not be an imaging biomarker for neurodegeneration in iRBD.
authors.affiliation: Department of Neurology, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, South Korea. Electronic address: jhlee.neuro@pusan.ac.kr.
authors.forename: Jae-Hyeok
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Biomedical Engineering, Inje University, Gimhae, South Korea.
authors.forename: Yong-Hee
authors.initials: YH
authors.lastname: Han
authors.affiliation: Department of Neurology, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, South Korea.
authors.forename: Jae-Wook
authors.initials: JW
authors.lastname: Cho
authors.affiliation: Department of Psychiatry, Pusan National University Yangsan Hospital, Yangsan, South Korea.
authors.forename: Jin-Seong
authors.initials: JS
authors.lastname: Lee
authors.affiliation: School of Korean Medicine, Pusan National University, Yangsan, South Korea.
authors.forename: Sang-Jae
authors.initials: SJ
authors.lastname: Lee
authors.affiliation: Department of Neurology, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, South Korea.
authors.forename: Dae-Jin
authors.initials: DJ
authors.lastname: Kim
authors.affiliation: Department of Neurology, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, South Korea.
authors.forename: Tae-Hyoung
authors.initials: TH
authors.lastname: Kim
authors.affiliation: Department of Biomedical Engineering, Inje University, Gimhae, South Korea.
authors.forename: Bok-Man
authors.initials: BM
authors.lastname: Kang
authors.affiliation: Department of Biomedical Engineering, Inje University, Gimhae, South Korea.
authors.forename: Tae-Hyung
authors.initials: TH
authors.lastname: Kim
authors.affiliation: Department of Biomedical Engineering, Inje University, Gimhae, South Korea.
authors.forename: Chi-Woong
authors.initials: CW
authors.lastname: Mun
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000378:metabolism; D001921:Brain / Q000378:metabolism*; D001923:Brain Chemistry / Q000502:physiology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007501:Iron / Q000032:analysis / Q000378:metabolism*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000175:diagnosis / Q000378:metabolism; D020187:REM Sleep Behavior Disorder / Q000175:diagnosis* / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D007501:Iron
keywords: Idiopathic REM sleep behavior disorder; Iron; MRI; Volume