The inter-observer agreement in the assessment of carotid plaque neovascularization by contrast-enhanced ultrasonography: The impact of plaque thickness

J Clin Ultrasound. 2018 Jul;46(6):403-407. doi: 10.1002/jcu.22595. Epub 2018 Apr 10.

Abstract

Background: The interobserver agreement in the assessment of the grade of carotid plaque neovascularization by contrast-enhanced ultrasonography is poorly established.

Method: We examined 140 carotid plaques in 66 patients (all patients had bilateral plaques, and 8 patients had 2 plaques on one side). We performed conventional and contrast-enhanced ultrasonography to analyze the presence of carotid plaque neovascularization, which was graded by two independent observers whose interobserver agreement (κ) was evaluated according to the thickness of carotid plaque.

Results: For all carotid plaques, the mean κ was 0.689 (95% confidence interval 0.604-0.774). It was 0.689 (0.569-0.808), 0.637 (0.487-0.787), and 0.740 (0.585-0.896), respectively for carotid plaques with maximal thickness <2 mm, from 2 mm to 3 mm, and >3 mm.

Conclusion: The interobserver agreement for assessing carotid plaque neovascularization by using contrast-enhanced ultrasonography is substantial and acceptable for research purposes, regardless of the maximal thickness of the plaque.

Keywords: carotid plaque; contrast-enhanced ultrasonography; interobserver agreement; neovascularization.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Carotid Arteries / diagnostic imaging
  • Carotid Arteries / pathology
  • Carotid Artery Diseases / diagnostic imaging*
  • Carotid Artery Diseases / pathology
  • Contrast Media*
  • Female
  • Humans
  • Image Enhancement / methods*
  • Male
  • Middle Aged
  • Neovascularization, Pathologic / diagnostic imaging
  • Neovascularization, Pathologic / pathology
  • Observer Variation
  • Plaque, Atherosclerotic / diagnostic imaging*
  • Plaque, Atherosclerotic / pathology
  • Severity of Illness Index
  • Ultrasonography / methods*

Substances

  • Contrast Media