title: Posterior lobules of the cerebellum and information processing speed at various stages of multiple sclerosis.
abstract: BACKGROUND
  Cerebellar damage has been implicated in information processing speed (IPS) impairment associated with multiple sclerosis (MS) that might result from functional disconnection in the frontocerebellar loop. Structural alterations in individual posterior lobules, in which cognitive functioning seems preponderant, are still unknown. Our aim was to investigate the impact of grey matter (GM) volume alterations in lobules VI to VIIIb on IPS in persons with clinically isolated syndrome (PwCIS), MS (PwMS) and healthy subjects (HS).
  
  
  METHODS
  69 patients (37 PwCIS, 32 PwMS) and 36 HS underwent 3 T MRI including 3-dimensional T1-weighted MRIs. Cerebellum lobules were segmented using SUIT V.3.0 to estimate their normalised GM volume. Neuropsychological testing was performed to assess IPS and main cognitive functions.
  
  
  RESULTS
  Normalised GM volumes were significantly different between PwMS and HS for the right (p<0.001) and left lobule VI (p<0.01), left crus I, right VIIb and entire cerebellum (p<0.05 for each comparison) and between PwMS and PwCIS for all lobules in subregions VI and left crus I (p<0.05). IPS, attention and working memory were impaired in PwMS compared with PwCIS. In the whole population of patients (PwMS and PwCIS), GM loss in vermis VI (R2=0.36; p<0.05 when considering age and T2 lesion volume as covariates) were associated with IPS impairment.
  
  
  CONCLUSIONS
  GM volume decrease in posterior lobules (especially vermis VI) was associated with reduced IPS. Our results suggest a significant impact of posterior lobules pathology in corticocerebellar loop disruption resulting in automation and cognitive optimisation lack in MS.
  
  
  BACKGROUND
  Clinicaltrail NCT01207856, NCT01865357; Pre-results.
authors: University Bordeaux, Bordeaux, France.|Services de Neurologie et Neuroradiologie, CHU de Bordeaux, INSERM-CHU CIC-P 0005, Bordeaux, France.|Neurocentre Magendie, INSERM U1215, Bordeaux, France.
authors: Amandine
authors: A
authors: Moroso
authors: University Bordeaux, Bordeaux, France.|Services de Neurologie et Neuroradiologie, CHU de Bordeaux, INSERM-CHU CIC-P 0005, Bordeaux, France.|Neurocentre Magendie, INSERM U1215, Bordeaux, France.
authors: Aurélie
authors: A
authors: Ruet
authors: University Bordeaux, Bordeaux, France.|Neurocentre Magendie, INSERM U1215, Bordeaux, France.
authors: Delphine
authors: D
authors: Lamargue-Hamel
authors: University Bordeaux, Bordeaux, France.|Neurocentre Magendie, INSERM U1215, Bordeaux, France.
authors: Fanny
authors: F
authors: Munsch
authors: Services de Neurologie et Neuroradiologie, CHU de Bordeaux, INSERM-CHU CIC-P 0005, Bordeaux, France.
authors: Mathilde
authors: M
authors: Deloire
authors: University Bordeaux, Bordeaux, France.|LaBRI, UMR 5800, PICTURA, Talence, France.
authors: Pierrick
authors: P
authors: Coupé
authors: Services de Neurologie et Neuroradiologie, CHU de Bordeaux, INSERM-CHU CIC-P 0005, Bordeaux, France.
authors: Jean-Christophe
authors: JC
authors: Ouallet
authors: University Bordeaux, Bordeaux, France.|Neurocentre Magendie, INSERM U1215, Bordeaux, France.
authors: Vincent
authors: V
authors: Planche
authors: Department of Radiology, Center for Neurological Imaging, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
authors: Nicolas
authors: N
authors: Moscufo
authors: Department of Radiology, Center for Neurological Imaging, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
authors: Dominik S
authors: DS
authors: Meier
authors: University Bordeaux, Bordeaux, France.|Services de Neurologie et Neuroradiologie, CHU de Bordeaux, INSERM-CHU CIC-P 0005, Bordeaux, France.|Neurocentre Magendie, INSERM U1215, Bordeaux, France.
authors: Thomas
authors: T
authors: Tourdias
authors: Department of Radiology, Center for Neurological Imaging, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
authors: Charles R G
authors: CR
authors: Guttmann
authors: University Bordeaux, Bordeaux, France.|Services de Neurologie et Neuroradiologie, CHU de Bordeaux, INSERM-CHU CIC-P 0005, Bordeaux, France.|Neurocentre Magendie, INSERM U1215, Bordeaux, France.
authors: Vincent
authors: V
authors: Dousset
authors: University Bordeaux, Bordeaux, France.|Services de Neurologie et Neuroradiologie, CHU de Bordeaux, INSERM-CHU CIC-P 0005, Bordeaux, France.|Neurocentre Magendie, INSERM U1215, Bordeaux, France.
authors: Bruno
authors: B
authors: Brochet
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology; D002531:Cerebellum / Q000000981:diagnostic imaging*; D003071:Cognition / Q000502:physiology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000000981:diagnostic imaging* / Q000523:psychology; D009483:Neuropsychological Tests; D009929:Organ Size / Q000502:physiology; D011930:Reaction Time / Q000502:physiology*; D055815:Young Adult