Ultrasonic tissue characterization of vulnerable carotid plaque: correlation between videodensitometric method and histological examination.
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.
Baroncini
Liz Andréa V
LA
Department of Internal Medicine - Faculdade de Medicina de Ribeirão Preto, University of São Paulo, São Paulo, Brazil. lizandreabaroncini@hotmail.com
Pazin Filho
Antonio
A
Murta Junior
Luiz O
LO
Martins
Antonio R
AR
Ramos
Simone G
SG
Cherri
Jesualdo
J
Piccinato
Carlos E
CE
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
D002118:Calcium