title: Nigral involvement and nigrostriatal dysfunction in Huntington's disease: evidences from an MRI and SPECT study.
abstract: BACKGROUND
  Huntington disease (HD) is pathologically characterized by a selective neurodegeneration of vulnerable populations of neurons, with an early marked neuronal loss and atrophy in the neostriatum. Dopaminergic innervations of neostriatal neurons originate in the substantia nigra pars compacta. Few studies investigated the neuronal loss and the functional role of the substantia nigra in modulating clinical features in HD.
  
  
  METHODS
  12 patients and 12 age-matched controls underwent SPECT scans with (123)I-FP-CIT and a 1.5 T MRI scan with inversion recovery technique. The association between both clinical and neuropsychological features and striatal uptake and volume of substantia nigra was explored.
  
  
  RESULTS
  Striatal (p < 0.05), caudate (p < 0.05), and putaminal (p < 0.01) uptake was significantly lower in patients with respect to controls. Further, the volume of substantia nigra was reduced in HD when compared to controls (p < 0.01). No relationship between the volume of SN and tracer striatal uptake was found as well as between clinical and neuropsychological features with the SPECT and MRI results.
  
  
  CONCLUSIONS
  Our results confirm that the degeneration of nigrostriatal pathway may occur in symptomatic HD patients. If confirmed by larger studies, the lack of any kind of correlation between clinical and neuropsychological features with striatal uptake and volume of substantia nigra suggests that motor and cognitive aspects in HD are not directly related to nigrostriatal degeneration.
authors.affiliation: Department of Clinical and Experimental Medicine, Section of Neurology, University of Pisa, Italy. l.kiferle@virgilio.it
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Kiferle
authors.forename: Sonia
authors.initials: S
authors.lastname: Mazzucchi
authors.forename: Elisa
authors.initials: E
authors.lastname: Unti
authors.forename: Ilaria
authors.initials: I
authors.lastname: Pesaresi
authors.forename: Serena
authors.initials: S
authors.lastname: Fabbri
authors.forename: Valentina
authors.initials: V
authors.lastname: Nicoletti
authors.forename: Duccio
authors.initials: D
authors.lastname: Volterrani
authors.forename: Mirco
authors.initials: M
authors.lastname: Cosottini
authors.forename: Ubaldo
authors.initials: U
authors.lastname: Bonuccelli
authors.forename: Roberto
authors.initials: R
authors.lastname: Ceravolo
mesh_terms: D000328:Adult; D000368:Aged; D003342:Corpus Striatum / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology*; D004298:Dopamine / Q000378:metabolism; D005260:Female; D006801:Humans; D006816:Huntington Disease / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009474:Neurons / Q000378:metabolism; D013378:Substantia Nigra / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology*; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods
chemical_list: D004298:Dopamine
keywords: Huntington's disease; MRI; Neuropsychiatry; SPECT; Substantia nigra