title: Association between carotid artery occlusion and ultrasonographic plaque type.
abstract: BACKGROUND
  Internal carotid artery (ICA) occlusion is associated with acute stroke and carries significant morbidity and mortality. The aim of this study was to examine whether ultrasonographic carotid plaque type may be associated with ICA occlusion.
  
  
  METHODS
  Two hundred eleven patients (85% men, mean age 66.0±9.5 years, 28.9% asymptomatic) with ICA occlusion were included in this case-control study. Ultrasonographic Gray-Weale plaque type (I-IV, echolucent to echogenic) characterization was obtained in both the occluded and the contralateral ICA. Univariate and conditional logistic regression analyses with 1:1 pair matching per artery were undertaken. Each contralateral carotid artery with stenosis was treated as control to the ipsilateral-occluded ICA of the same patient.
  
  
  RESULTS
  A total of 261 ICAs (61.9%) were recorded with type I-II plaque, of which 165 (63.2%) were among the occluded and 96 (36.8%) were among the contralateral ICAs with stenosis (P<0.001). Mean contralateral ICA stenosis was 58.2%±20.4%. Regression analysis showed that carotid plaque type I-II was significantly associated with carotid artery occlusion compared with plaque type III-IV (crude odds ratio [OR]=4.29, 95% confidence intervals [CI]=2.81-6.57%, P<0.001, adjusted OR=5.60, 95% CI=3.23-9.70, P<0.001). Previous neurological events did not seem to be significantly associated with plaque echolucency (OR=0.62, 95% CI=0.29-1.35, P=0.23).
  
  
  CONCLUSIONS
  A significant association between echolucent plaque and ICA occlusion was observed. This observational hypothesis may prompt for further investigation of the causal mechanism between carotid plaque type and ICA occlusion by larger cohort studies.
authors: Department of Vascular Surgery, University of Athens Medical School, Attikon University Hospital, Athens, Greece.
authors: Constantine N
authors: CN
authors: Antonopoulos
authors: Department of Vascular Surgery, University of Athens Medical School, Attikon University Hospital, Athens, Greece. Electronic address: gsfyr@yahoo.gr.
authors: George S
authors: GS
authors: Sfyroeras
authors: Department of Vascular Surgery, University of Athens Medical School, Attikon University Hospital, Athens, Greece.
authors: Konstantinos G
authors: KG
authors: Moulakakis
authors: Department of Vascular Surgery, University of Athens Medical School, Attikon University Hospital, Athens, Greece.
authors: Triantafillos G
authors: TG
authors: Giannakopoulos
authors: Department of Vascular Surgery, University of Athens Medical School, Attikon University Hospital, Athens, Greece.
authors: Ioannis
authors: I
authors: Vassilopoulos
authors: Department of Vascular Surgery, University of Athens Medical School, Attikon University Hospital, Athens, Greece.
authors: Anastasios
authors: A
authors: Papapetrou
authors: Department of Vascular Surgery, University of Athens Medical School, Attikon University Hospital, Athens, Greece.
authors: John
authors: J
authors: Kakisis
authors: Department of Vascular Surgery, University of Athens Medical School, Attikon University Hospital, Athens, Greece.
authors: Christos D
authors: CD
authors: Liapis
mesh_terms: D000368:Aged; D002340:Carotid Artery Diseases / Q000000981:diagnostic imaging; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging*; D016893:Carotid Stenosis / Q000000981:diagnostic imaging* / Q000209:etiology; D003937:Diagnosis, Differential; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D058226:Plaque, Atherosclerotic / Q000150:complications / Q000000981:diagnostic imaging*; D012189:Retrospective Studies; D012307:Risk Factors; D018616:Ultrasonography, Doppler, Duplex / Q000379:methods*