Three-dimensional ultrasound imaging for the evaluation of carotid atherosclerosis

IntroductionEmerging data suggests that 3-dimensional (D) ultrasound (US) may provide us with a new tool for the identification of the vulnerable carotid plaque.MethodsA systematic review of the PubMed, Scopus and Cochrane databases regarding the reproducibility and effectiveness of 3D US in evaluation of carotid plaque disease (CPD) was performed.ResultsSeven studies on the reproducibility of 3D ultrasound evaluation of plaque volume (PV) were identified. All studies reported good intra- and inter-observer reproducibility ranging from 2.8-6.0% to 4.2-7.6%, respectively. In addition, ten studies evaluating 3D carotid plaque progression with and without treatment were retrieved. In the 4 studies where 2D and 3D US features were compared, PV rather than intima media thickness (IMT) was a more sensitive marker of plaque change as a response to treatment. However, there were no studies evaluating changes in plaque morphology or specific composition features post-treatment with both 2 and 3D US. Finally, only one study was identified regarding the 3D composition differences of CPD between symptomatic and asymptomatic patients.ConclusionThe current evidence supports the good reproducibility of the 3D US on the evaluation of carotid plaque volume, however with high heterogeneity between studies. There is also preliminary evidence that PV measurements may be more sensitive than IMT in the identification of plaque change post-treatment, though, more plaque-related evidence is necessary. Further research is needed to establish if 3D is superior to 2D US in the identification of the vulnerable carotid plaque in clinical settings.