title: Structural brain abnormalities in patients with Parkinson disease: a comparative voxel-based analysis using T1-weighted MR imaging and magnetization transfer imaging.
abstract: OBJECTIVE
  In PD, tissue damage occurs in specific cortical and subcortical regions. Conventional MR images have only limited capacity to depict these structural changes. The purpose of the current study was to investigate whether voxel-based MT imaging could indicate structural abnormalities beyond atrophy measurable with T1-weighted MR imaging.
  
  
  METHODS
  Thirty-six patients with PD without dementia (9 in H&Y stage 1, thirteen in H&Y 2, eleven in H&Y 3, three in H&Y 4) and 23 age-matched control subjects were studied with T1-weighted MR imaging and MT imaging. Voxel-based analyses of T1-weighted MR imaging was performed to investigate brain atrophy, while MT imaging was used to study abnormalities within existing tissue. Modulated GM and WM probability maps, sensitive to volume, and nonmodulated maps, indicative of tissue density, were obtained from T1-weighted MR imaging. Effects seen on MTR images, but absent on density maps, were attributed to damage of existing tissue.
  
  
  RESULTS
  Contrary to T1-weighted MR imaging, MT imaging was sensitive to the progression of brain pathology of the neocortex and paraventricular WM. MTR images and T1-based volume images, but not density images, showed a progression of disease in the olfactory cortex, indicating the occurrence of atrophy as well as damage to existing tissue in this region. MTR images revealed bilateral damage to the SN, while T1-weighted MR imaging only showed left-sided abnormalities.
  
  
  CONCLUSIONS
  The findings suggest that voxel-based MT imaging permits a whole-brain unbiased investigation of CNS structural integrity in PD and may be a valuable tool for identifying structural damage occurring without or before measurable atrophy.
authors.affiliation: Central Institute of Mental Health, Mannheim, Germany. Katrin.Morgen@zi-mannheim.de
authors.forename: K
authors.initials: K
authors.lastname: Morgen
authors.forename: G
authors.initials: G
authors.lastname: Sammer
authors.forename: L
authors.initials: L
authors.lastname: Weber
authors.forename: B
authors.initials: B
authors.lastname: Aslan
authors.forename: C
authors.initials: C
authors.lastname: Müller
authors.forename: G F
authors.initials: GF
authors.lastname: Bachmann
authors.forename: D
authors.initials: D
authors.lastname: Sandmann
authors.forename: M
authors.initials: M
authors.lastname: Oechsner
authors.forename: D
authors.initials: D
authors.lastname: Vaitl
authors.forename: M
authors.initials: M
authors.lastname: Kaps
authors.forename: I
authors.initials: I
authors.lastname: Reuter
mesh_terms: D000465:Algorithms; D001921:Brain / Q000473:pathology*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
references.citation: Neurology. 2005 Apr 26;64(8):1404-10
references.pmid: 15851731
references.citation: J Psychiatr Res. 1975 Nov;12(3):189-98
references.pmid: 1202204
references.citation: J Neurol Neurosurg Psychiatry. 2006 Jan;77(1):40-5
references.pmid: 16361590
references.citation: Neurology. 1967 May;17(5):427-42
references.pmid: 6067254
references.citation: Neurology. 2008 Sep 16;71(12):903-10
references.pmid: 18794492
references.citation: J Neurol Neurosurg Psychiatry. 1988 Jun;51(6):745-52
references.pmid: 2841426
references.citation: Neuroradiology. 2003 Apr;45(4):224-30
references.pmid: 12687305
references.citation: Neurobiol Aging. 2003 Mar-Apr;24(2):197-211
references.pmid: 12498954
references.citation: Parkinsonism Relat Disord. 2009 Feb;15(2):88-93
references.pmid: 18434233
references.citation: J Neurol Neurosurg Psychiatry. 2007 Mar;78(3):254-9
references.pmid: 17028119
references.citation: Neuroimage. 2004 Jan;21(1):229-35
references.pmid: 14741660
references.citation: Neuroimage. 2009 Aug 15;47(2):435-41
references.pmid: 19447183
references.citation: Arch Neurol. 2005 Feb;62(2):281-5
references.pmid: 15710857
references.citation: Brain. 2004 Apr;127(Pt 4):791-800
references.pmid: 14749292
references.citation: J Neuroimaging. 2004 Oct;14(4):303-13
references.pmid: 15358949
references.citation: Mov Disord. 2010 Sep 15;25(12):1774-9
references.pmid: 20839307
references.citation: Acta Neuropathol. 1998 Jun;95(6):576-82
references.pmid: 9650749
references.citation: Ann Neurol. 1994 Jul;36(1):62-7
references.pmid: 8024264
references.citation: Brain. 2006 Feb;129(Pt 2):538-42
references.pmid: 16272163
references.citation: Neuroimage. 2001 Jul;14(1 Pt 1):21-36
references.pmid: 11525331
references.citation: AJNR Am J Neuroradiol. 2008 Mar;29(3):501-5
references.pmid: 18202242
references.citation: Arch Neurol. 2005 Mar;62(3):378-82
references.pmid: 15767502
references.citation: J Neurosci. 2006 Nov 22;26(47):12266-73
references.pmid: 17122052
references.citation: Mov Disord. 2009 Nov 15;24(15):2233-41
references.pmid: 19768730
references.citation: Neurology. 2005 Jan 25;64(2):224-9
references.pmid: 15668417
references.citation: Neurobiol Aging. 2008 Jul;29(7):1027-39
references.pmid: 17368653
references.citation: AJNR Am J Neuroradiol. 1999 Sep;20(8):1500-6
references.pmid: 10512237