Is 3D ultrasound reliable for the evaluation of carotid disease? A systematic review and meta-analysis

Studies assessing the use of 3D ultrasound (3DUS) for the evaluation of carotid disease reported varying views among observers about its reliability vis-à-vis 2DUS or angiography; ratings provided ranged from poor to excellent. Thisstudy aims to systematically review and analyze the reliability of 3DUS for the evaluation of carotid disease.The PubMed database was searched for studies that evaluated carotid disease (i.e. plaque measurements and characteristics and degree of stenosis) using 3DUS.Sixteen studies comprising a total of 918 stenosed carotids were reviewed and meta-analyzed. Data on intra- and inter-observer reproducibility and inter-method agreement (i.e. 3DUS vs 2D and 3DUS vs angiography) were analyzed. Overall analysis showed excellent intra- and inter-observer reproducibility (intraobserver: correlation coefficient r=0.88, 95% confidence intervals (CI) 0.84-0.92; intra-observer: r=0.91, 95% CI 0.87-0.95). The analysis also showed excellent agreement between 3DUS and 2DUS (r=0.89, 95% CI 0.83-0.95) and between 3DUS and angiography (r=0.73, 95% CI 0.44-0.1).3DUS has excellent intra- and inter-observer reproducibility and excellent agreement with 2DUS and angiography for the evaluation of carotid disease. Further studies assessing the reliability ofcarotid plaque characteristics using 3DUS in symptomatic and asymptomatic patients are required.