title: Resting bold fMRI differentiates dementia with Lewy bodies vs Alzheimer disease.
abstract: OBJECTIVE
  Clinicopathologic phenotypes of dementia with Lewy bodies (DLB) and Alzheimer disease (AD) often overlap, making discrimination difficult. We performed resting state blood oxygen level-dependent (BOLD) functional connectivity MRI (fcMRI) to determine whether there were differences between AD and DLB.
  
  
  METHODS
  Participants (n = 88) enrolled in a longitudinal study of memory and aging underwent 3-T fcMRI. Clinical diagnoses of probable DLB (n = 15) were made according to published criteria. Cognitively normal control participants (n = 38) were selected for the absence of cerebral amyloid burden as imaged with Pittsburgh compound B (PiB). Probable AD cases (n = 35) met published criteria and had appreciable amyloid deposits with PiB imaging. Functional images were collected using a gradient spin-echo sequence sensitive to BOLD contrast (T2* weighting). Correlation maps selected a seed region in the combined bilateral precuneus.
  
  
  RESULTS
  Participants with DLB had a functional connectivity pattern for the precuneus seed region that was distinct from AD; both the DLB and AD groups had functional connectivity patterns that differed from the cognitively normal group. In the DLB group, we found increased connectivity between the precuneus and regions in the dorsal attention network and the putamen. In contrast, we found decreased connectivity between the precuneus and other task-negative default regions and visual cortices. There was also a reversal of connectivity in the right hippocampus.
  
  
  CONCLUSIONS
  Changes in functional connectivity in DLB indicate patterns of activation that are distinct from those seen in AD and may improve discrimination of DLB from AD and cognitively normal individuals. Since patterns of connectivity differ between AD and DLB groups, measurements of BOLD functional connectivity can shed further light on neuroanatomic connections that distinguish DLB from AD.
authors.affiliation: Center of Excellence on Brain Aging, New York University Langone School of Medicine, 145 East 32nd St, Second Floor, New York, NY 10016, USA. James.Galvin@nyumc.org
authors.forename: J E
authors.initials: JE
authors.lastname: Galvin
authors.forename: J L
authors.initials: JL
authors.lastname: Price
authors.forename: Z
authors.initials: Z
authors.lastname: Yan
authors.forename: J C
authors.initials: JC
authors.lastname: Morris
authors.forename: Y I
authors.initials: YI
authors.lastname: Sheline
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000175:diagnosis / Q000473:pathology* / Q000503:physiopathology*; D006801:Humans; D020961:Lewy Body Disease / Q000175:diagnosis / Q000473:pathology* / Q000503:physiopathology*; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D010100:Oxygen / Q000097:blood*
chemical_list: D010100:Oxygen