title: Patterns of brain computed tomography infarction and carotid plaque echogenicity.
abstract: OBJECTIVE
  It was suggested that in the absence of cardioembolism the discrete subcortical and cortical infarctions on brain computed tomography (CT) are most likely associated with carotid atheroma, whereas the hemodynamic infarctions, diffuse widespread white matter lesions, lacunae and basal ganglia infarctions are most likely associated with other pathologic conditions. The aim of this study was to determine the ultrasonic characteristics of carotid plaques and the degree of stenosis that were associated with the different brain CT infarction patterns and normal CT (pattern A, discrete subcortical and cortical infarctions; pattern B, hemodynamic infarctions, diffuse widespread white matter lesions, lacunae and basal ganglia infarctions).
  
  
  METHODS
  Four hundred nineteen carotid plaques (315 patients), producing 50% to 99% stenosis on duplex scanning, were studied. These plaques were imaged on duplex scanning, captured, digitized, and normalized (standardized) in a computer. Subsequently, their gray scale median (GSM) was evaluated to distinguish quantitatively the hypoechoic (low GSM) from the hyperechoic (high GSM) plaques. The brain CT infarction patterns of A, B, or normal CT on the ipsilateral hemisphere were noted.
  
  
  RESULTS
  The pattern A brain CT infarction was associated with carotid plaques having median GSM of 11 and median degree of stenosis of 80%, as contrasted with pattern B (median GSM, 28.5; median degree of stenosis, 75%) or normal CT (median GSM, 22; median degree of stenosis, 75%) (Kruskal-Wallis test, P <.001 for the GSM and P =.002 for the degree of stenosis). In the logistic regression analysis only the GSM and not the degree of stenosis distinguished the plaques associated with the three CT patterns.
  
  
  CONCLUSIONS
  The pattern A brain CT infarction was associated with hypoechoic plaques suggesting an involvement of extracranial carotid artery embolization, whereas the pattern B was associated with hyperechoic plaques suggesting an involvement of other mechanisms (hemodynamic, intracranial small and large vessel disease).
authors.affiliation: Irvine Laboratory for Cardiovascular Investigation and Research, the Department of Vascular Surgery, Imperial College of Science, Technology, and Medicine, St Mary's Campus, London, United Kingdom. t.tegos@ic.ac.uk
authors.forename: T J
authors.initials: TJ
authors.lastname: Tegos
authors.forename: M M
authors.initials: MM
authors.lastname: Sabetai
authors.forename: A N
authors.initials: AN
authors.lastname: Nicolaides
authors.forename: T S
authors.initials: TS
authors.lastname: Elatrozy
authors.forename: S
authors.initials: S
authors.lastname: Dhanjil
authors.forename: J M
authors.initials: JM
authors.lastname: Stevens
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity; D001921:Brain / Q000000981:diagnostic imaging*; D002340:Carotid Artery Diseases / Q000150:complications / Q000000981:diagnostic imaging*; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging*; D016893:Carotid Stenosis / Q000150:complications / Q000000981:diagnostic imaging; D002544:Cerebral Infarction / Q000150:complications / Q000000981:diagnostic imaging*; D002560:Cerebrovascular Circulation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed; D018608:Ultrasonography, Doppler