title: Cerebral perfusion affects the risk of ischemia during carotid artery stenting.
abstract: BACKGROUND
  Patients with impaired perfusion in the hemisphere ipsilateral to a stenotic internal carotid artery may have a higher risk of cerebral ischemic complications than those with normal perfusion. We therefore studied whether the occurrence of new ischemic lesions after carotid artery stenting is related to cerebral perfusion.
  
  
  METHODS
  In 45 patients with symptomatic carotid artery stenosis, CT perfusion and magnetic resonance diffusion-weighted imaging (DWI) were performed before carotid artery stenting; DWI was repeated within 2 days thereafter. Cerebral blood volume (CBV), mean transit time (MTT), and cerebral blood flow (CBF) were measured with CT perfusion in the cortical flow territory of the middle cerebral artery. Hyperintense lesions on postprocedural DWI not visible on baseline DWI were considered new cerebral ischemic lesions. The relation between CBF, CBV, and MTT and new ipsilateral ischemic lesions was tested with logistic regression.
  
  
  RESULTS
  In 11 of the 45 (24%) patients, new ischemic lesions were found in the ipsilateral hemisphere. The occurrence of these lesions was related to a lower CBF [adjusted odds ratio (aOR), 0.96; 95% confidence interval (CI), 0.92-1.00] and a longer MTT (aOR, 1.65; 95% CI, 1.02-2.66) compared with ipsilateral hemispheres without new lesions.
  
  
  CONCLUSIONS
  Patients with impaired cerebral perfusion are more prone to develop ischemic lesions during carotid artery stenting. This suggests that in ischemic stroke during or after carotid artery stenting, embolic and hemodynamic mechanisms act in concert.
authors.affiliation: Department of Radiology, Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, Utrecht, The Netherlands. L.Jongen@umcutrecht.nl
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Jongen
authors.forename: Jeroen
authors.initials: J
authors.lastname: Hendrikse
authors.forename: Frans L
authors.initials: FL
authors.lastname: Moll
authors.forename: Willem P T M
authors.initials: WP
authors.lastname: Mali
authors.forename: H Bart
authors.initials: HB
authors.lastname: van der Worp
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001810:Blood Volume / Q000502:physiology; D002545:Brain Ischemia / Q000209:etiology* / Q000503:physiopathology; D002339:Carotid Arteries / Q000601:surgery*; D016893:Carotid Stenosis / Q000628:therapy; D002533:Cerebral Angiography; D002560:Cerebrovascular Circulation / Q000502:physiology*; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015607:Stents / Q000009:adverse effects*; D014057:Tomography, X-Ray Computed