title: Usefulness of Diffusion-Weighted MRI for Differentiation between Parkinson's Disease and Parkinson Variant of Multiple System Atrophy.
abstract: OBJECTIVE
  Several studies have reported that diffusion-weighted imaging (DWI) is able to help discriminate a Parkinson variant of multiple system atrophy (MSA-p) from Parkinson's disease (PD) on the basis of the increased regional apparent diffusion coefficient (rADC). We analyzed the usefulness of DWI by using the rADC for differential diagnosis between MSA-p and PD and investigated the correlation between the rADC value and clinical features of MSA-p and PD.
  
  
  METHODS
  Twelve patients with PD and 10 with MSA-p were studied. The rADC value was determined in different brain regions, including the dorsal putamen (DP) and middle cerebellar peduncles (MCP).
  
  
  RESULTS
  The rADC values of the DP showed a greater increase in MSA-p patients than in PD patients (p=0.03). MSA-p patients also presented increased rADC values of the MCP compared with PD patients (p=0.0001). In particular, the sensitivity, specificity and positive predictive values of the MCP rADC were higher than those of the DP rADC. However, DP and MCP rADC values were not correlated with clinical features in either MSA or PD patients.
  
  
  CONCLUSIONS
  DWI discriminated between PD and MSA-p based on rADC values in DP and MCP. The MCP rADC value, in particular, could better discriminate MSA-p from PD.
authors.affiliation: Departments of Neurology, Inje University College of Medicine, Busan, Korea.
authors.forename: Eun Joo
authors.initials: EJ
authors.lastname: Chung
authors.affiliation: Departments of Neurology, Inje University College of Medicine, Busan, Korea.
authors.forename: Eung Gyu
authors.initials: EG
authors.lastname: Kim
authors.affiliation: Departments of Neurology, Inje University College of Medicine, Busan, Korea.
authors.forename: Jong Seok
authors.initials: JS
authors.lastname: Bae
authors.affiliation: Radiology, Pusan Paik Hospital, Inje University College of Medicine, Busan, Korea.
authors.forename: Choong Ki
authors.initials: CK
authors.lastname: Eun
authors.affiliation: Radiology, Pusan Paik Hospital, Inje University College of Medicine, Busan, Korea.
authors.forename: Kwang Sig
authors.initials: KS
authors.lastname: Lee
authors.affiliation: Clinical Trial Center, Inje University, Pusan Paik Hospital, Busan, Korea.
authors.forename: Minkyung
authors.initials: M
authors.lastname: Oh
authors.affiliation: Departments of Neurology, Inje University College of Medicine, Busan, Korea.
authors.forename: Sang Jin
authors.initials: SJ
authors.lastname: Kim
keywords: Diffusion-weighted imaging; Multiple system atrophy; Parkinson’s disease