title: T1 gadolinium enhancement of intracranial atherosclerotic plaques associated with symptomatic ischemic presentations.
abstract: OBJECTIVE
  Contrast enhancement of intracranial atherosclerotic plaques has recently been investigated using high field and high resolution MR imaging as a risk factor in the development of ischemic stroke. We studied the reliability of conventional MR imaging at 1.5T in evaluating intraplaque enhancement and its relationship with acute cerebrovascular ischemic presentations in patients with severe intracranial atherosclerotic disease.
  
  
  METHODS
  We retrospectively identified and analyzed 19 patients with 22 high-grade intracranial atherosclerotic disease plaques (>70% stenosis) in vessels cross-sectionally visualized by neuroanatomic MR imaging. Atherosclerotic plaques were classified as asymptomatic or symptomatic. Two blinded neuroradiologists independently ranked each lesion for the presence of intraplaque enhancement by use of a 5-point scale (1-5). Furthermore, plaque enhancement was quantified as the relative change in T1WI spin-echo signal intensity (postcontrast/precontrast) in the vessel wall at the site of each intracranial atherosclerotic disease lesion.
  
  
  RESULTS
  Intraplaque enhancement was observed in 7 of 10 (70%) symptomatic plaques, in contrast to 1 of 12 (8%) asymptomatic plaques. Interobserver reliability correlated well for intraplaque enhancement (κ = 0.82). The degree of relative plaque enhancement in symptomatic versus asymptomatic lesions (63% versus 23%) was statistically significant (P = .001, t test).
  
  
  CONCLUSIONS
  In this pilot study, we determined that intraplaque enhancement could be reliably evaluated with the use of cross-sectional imaging and analysis of vessels/plaques by use of conventional neuroanatomic MR imaging protocols. In addition, we observed a strong association between intraplaque enhancement in severe intracranial atherosclerotic disease lesions and ischemic events with the use of conventional MR imaging. Our preliminary study suggests that T1 gadolinium-enhancing plaques may be an indicator of progressing or symptomatic intracranial atherosclerotic disease.
authors.affiliation: Departments of Radiology.
authors.forename: P
authors.initials: P
authors.lastname: Vakil
authors.forename: J
authors.initials: J
authors.lastname: Vranic
authors.forename: M C
authors.initials: MC
authors.lastname: Hurley
authors.forename: R A
authors.initials: RA
authors.lastname: Bernstein
authors.forename: A W
authors.initials: AW
authors.lastname: Korutz
authors.forename: A
authors.initials: A
authors.lastname: Habib
authors.forename: A
authors.initials: A
authors.lastname: Shaibani
authors.forename: F H
authors.initials: FH
authors.lastname: Dehkordi
authors.forename: T J
authors.initials: TJ
authors.lastname: Carroll
authors.forename: S A
authors.initials: SA
authors.lastname: Ansari
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002545:Brain Ischemia / Q000209:etiology* / Q000473:pathology*; D005260:Female; D005682:Gadolinium; D006801:Humans; D002537:Intracranial Arteriosclerosis / Q000150:complications* / Q000473:pathology*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D005682:Gadolinium