title: Extracranial carotid plaque length and parent vessel diameter significantly affect baseline ipsilateral intracranial blood flow.
abstract: BACKGROUND
  The degree of carotid artery stenosis has traditionally been used as a marker of hemodynamic compromise and increased stroke risk. However, the hemodynamic effect of carotid atherosclerotic plaque length on cerebral blood flow has not previously been studied.
  
  
  OBJECTIVE
  To determine whether carotid plaque length, in addition to degree of stenosis, significantly affects carotid blood flow in patients with >65% carotid stenosis.
  
  
  METHODS
  Consecutively treated surgical patients with unilateral >65% carotid stenosis at a single institution were analyzed. Quantitative measurements of plaque length, internal carotid artery (ICA) vessel diameter, and degree of stenosis were made from magnetic resonance angiography images. Quantitative phase-contrast magnetic resonance angiography flow maps were generated to estimate ICA flow compromise by calculating a ratio of the ipsilateral/contralateral ICA flow rates.
  
  
  RESULTS
  Of 38 eligible patients, 23 had full anatomic and ICA flow data sets available for analysis. Univariate regression analysis demonstrated that longer carotid plaques and increasing percentage carotid stenosis were associated with a significant decline in ipsilateral ICA flow (P = .008 and P = .02, respectively). A multivariate regression identified both plaque length and vessel diameter as independent predictors of ICA flow (P = .001 and P = .002, respectively).
  
  
  CONCLUSIONS
  Carotid plaque length and vessel diameter appear to be significant variables, in addition to degree of stenosis, in predicting ipsilateral carotid blood flow compromise in patients undergoing carotid revascularization.
authors.affiliation: Wallace Trials Center, Greenwich Hospital, Greenwich, CT, USA. afdouglasmd@aol.com
authors.forename: Andrea F
authors.initials: AF
authors.lastname: Douglas
authors.forename: Susan
authors.initials: S
authors.lastname: Christopher
authors.forename: Nduka
authors.initials: N
authors.lastname: Amankulor
authors.forename: Ryan
authors.initials: R
authors.lastname: Din
authors.forename: Mike
authors.initials: M
authors.lastname: Poullis
authors.forename: Sepideh
authors.initials: S
authors.lastname: Amin-Hanjani
authors.forename: Zoher
authors.initials: Z
authors.lastname: Ghogawala
mesh_terms: D000368:Aged; D001921:Brain / Q000098:blood supply*; D016893:Carotid Stenosis / Q000150:complications / Q000473:pathology*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D007839:Functional Laterality; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged