title: Nicotinic alpha4beta2 receptor binding in dementia with Lewy bodies using 123I-5IA-85380 SPECT demonstrates a link between occipital changes and visual hallucinations.
abstract: BACKGROUND
  To investigate in vivo differences in the distribution of alpha4beta2 subtypes of nAChR using the ligand (123)I-5-Iodo-3-[2(S)-2-azetidinylmethoxy] pyridine (5IA-85380) and single photon emission computed tomography (SPECT) in DLB and similarly aged controls.
  
  
  METHODS
  Thirty-one subjects (15 DLB and 16 controls) underwent (123)I-5IA-85380 and perfusion ((99m)Tc-exametazime) SPECT scanning. Patient scans were compared to scans of control subjects on a voxel-by-voxel basis using SPM2.
  
  
  RESULTS
  Compared to controls, significant reductions in relative (123)I-5IA-85380 uptake were identified in frontal, striatal, temporal and cingulate regions in DLB. Elevation of scaled (123)I-5IA-85380 uptake in occipital cortex was observed in DLB relative to controls, as well as being associated with DLB subjects with a recent history of visual hallucinations. Changes in (123)I-5IA-85380 SPECT in DLB were different from perfusion.
  
  
  CONCLUSIONS
  Reductions in normalised (123)I-5IA-85380 uptake in DLB were distinct from their perfusion deficits. Significant increase in occipital lobe uptake was present in DLB, a change most pronounced in subjects with a recent history of visual hallucinations. The findings directly link cholinergic changes in occipital lobe to visual hallucinations in DLB.
authors.affiliation: Institute for Ageing and Health, Newcastle University, Wolfson Research Centre, Newcastle General Hospital, Westgate Road, Newcastle upon Tyne NE4 6BE, UK.
authors.forename: John T
authors.initials: JT
authors.lastname: O'Brien
authors.forename: Sean J
authors.initials: SJ
authors.lastname: Colloby
authors.forename: Sanjeet
authors.initials: S
authors.lastname: Pakrasi
authors.forename: Elaine K
authors.initials: EK
authors.lastname: Perry
authors.forename: Sally L
authors.initials: SL
authors.lastname: Pimlott
authors.forename: David J
authors.initials: DJ
authors.lastname: Wyper
authors.forename: Ian G
authors.initials: IG
authors.lastname: McKeith
authors.forename: E David
authors.initials: ED
authors.lastname: Williams
mesh_terms: D000368:Aged; D001384:Azetidines; D002074:Butanones; D005260:Female; D006212:Hallucinations / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000503:physiopathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D020961:Lewy Body Disease / Q000000981:diagnostic imaging* / Q000378:metabolism*; D008297:Male; D009483:Neuropsychological Tests; D009778:Occipital Lobe / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000503:physiopathology*; D011725:Pyridines; D019275:Radiopharmaceuticals; D011978:Receptors, Nicotinic / Q000378:metabolism*; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: C426745:5-iodo-3-(2-azetidinylmethoxy)pyridine; D001384:Azetidines; D002074:Butanones; D011725:Pyridines; D019275:Radiopharmaceuticals; D011978:Receptors, Nicotinic; C403531:nicotinic receptor alpha4beta2; C078058:exametazime