title: ADC mapping of chronic cerebral hypoperfusion induced by carotid artery stenosis.
abstract: BACKGROUND
  Carotid artery stenosis is associated with the occurrence of acute and chronic ischemic lesions that increase with age in the elderly population. Diffusion Imaging and ADC mapping may be an appropriate method to investigate patients with chronic hypoperfusion consecutive to carotid stenosis. This non-invasive technique allows to investigate brain integrity and structure, in particular hypoperfusion induced by carotid stenosis diseases. The aim of this study was to evaluate the impact of a carotid stenosis on the parenchyma using ADC mapping.
  
  
  METHODS
  Fifty-nine patients with symptomatic (33) and asymptomatic (26) carotid stenosis were recruited from our multidisciplinary consultation. Both groups demonstrated a similar degree of stenosis. All patients underwent MRI of the brain including diffusion-weighted MR imaging with ADC mapping. Regions of interest were defined in the anterior and posterior paraventricular regions both ipsilateral and contralateral to the stenosis (anterior circulation). The same analysis was performed for the thalamic and occipital regions (posterior circulation).
  
  
  RESULTS
  ADC values of the affected vascular territory were significantly higher on the side of the stenosis in the periventricular anterior (P<0.001) and posterior (P<0.01) area. There was no difference between ipsilateral and contralateral ADC values in the thalamic and occipital regions.
  
  
  CONCLUSIONS
  We have shown that carotid stenosis is associated with significantly higher ADC values in the anterior circulation, probably reflecting an impact of chronic hypoperfusion on the brain parenchyma in symptomatic and asymptomatic patients. This is consistent with previous data in the literature.
authors.affiliation: Department of neuroradiology, DISIM, Geneva University Hospital and Medical School, 4, rue Gabrielle-Perret-Gentil, 1211 Geneva 4, Switzerland.
authors.forename: V
authors.initials: V
authors.lastname: Rentsch-Granges
authors.forename: F
authors.initials: F
authors.lastname: Assal
authors.forename: V Mendes
authors.initials: VM
authors.lastname: Pereira
authors.forename: A
authors.initials: A
authors.lastname: Alimenti
authors.forename: P
authors.initials: P
authors.lastname: Mosimann
authors.forename: A
authors.initials: A
authors.lastname: de Ribaupierre
authors.forename: F
authors.initials: F
authors.lastname: Lazeyras
authors.forename: C D
authors.initials: CD
authors.lastname: Becker
authors.forename: R
authors.initials: R
authors.lastname: Sztajzel
authors.forename: D
authors.initials: D
authors.lastname: Rüfenacht
authors.forename: K-O
authors.initials: KO
authors.lastname: Lövblad
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000098:blood supply* / Q000473:pathology / Q000503:physiopathology; D002545:Brain Ischemia / Q000209:etiology / Q000473:pathology / Q000503:physiopathology*; D016893:Carotid Stenosis / Q000150:complications / Q000473:pathology / Q000503:physiopathology*; D002560:Cerebrovascular Circulation; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D059906:Neuroimaging