title: Ultrasonic tissue characterization of vulnerable carotid plaque: correlation between videodensitometric method and histological examination.
abstract: BACKGROUND
  To establish the correlation between quantitative analysis based on B-mode ultrasound images of vulnerable carotid plaque and histological examination of the surgically removed plaque, on the basis of a videodensitometric digital texture characterization.
  
  
  METHODS
  Twenty-five patients (18 males, mean age 67 +/- 6.9 years) admitted for carotid endarterectomy for extracranial high-grade internal carotid artery stenosis (> or = 70% luminal narrowing) underwent to quantitative ultrasonic tissue characterization of carotid plaque before surgery. A computer software (Carotid Plaque Analysis Software) was developed to perform the videodensitometric analysis. The patients were divided into 2 groups according to symptomatology (group I, 15 symptomatic patients; and group II, 10 patients asymptomatic). Tissue specimens were analysed for lipid, fibromuscular tissue and calcium.
  
  
  RESULTS
  The first order statistic parameter mean gray level was able to distinguish the groups I and II (p = 0.04). The second order parameter energy also was able to distinguish the groups (p = 0,02). A histological correlation showed a tendency of mean gray level to have progressively greater values from specimens with < 50% to > 75% of fibrosis.
  
  
  CONCLUSIONS
  Videodensitometric computer analysis of scan images may be used to identify vulnerable and potentially unstable lipid-rich carotid plaques, which are less echogenic in density than stable or asymptomatic, more densely fibrotic plaques.
authors.affiliation: Department of Internal Medicine - Faculdade de Medicina de Ribeirão Preto, University of São Paulo, São Paulo, Brazil. lizandreabaroncini@hotmail.com
authors.forename: Liz Andréa V
authors.initials: LA
authors.lastname: Baroncini
authors.forename: Antonio
authors.initials: A
authors.lastname: Pazin Filho
authors.forename: Luiz O
authors.initials: LO
authors.lastname: Murta Junior
authors.forename: Antonio R
authors.initials: AR
authors.lastname: Martins
authors.forename: Simone G
authors.initials: SG
authors.lastname: Ramos
authors.forename: Jesualdo
authors.initials: J
authors.lastname: Cherri
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Piccinato
mesh_terms: D000368:Aged; D002118:Calcium / Q000378:metabolism; D002339:Carotid Arteries / Q000378:metabolism / Q000473:pathology; D016893:Carotid Stenosis / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D003720:Densitometry / Q000379:methods; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000592:standards; D050356:Lipid Metabolism; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D014463:Ultrasonography; D014741:Video Recording
chemical_list: D002118:Calcium