Feasibility of dynamic three-dimensional contrast-enhanced ultrasound in focal liver lesions: Image quality evaluation and correlation of quantification with two-dimensional contrast-enhanced ultrasound

BACKGROUND: Dynamic three-dimensional contrast-enhanced ultrasound (3D-CEUS) with quantitative analysis is updated in recent years. OBJECTIVE: To explore the feasibility of dynamic 3D-CEUS in evaluation of dynamic vascular patterns of focal liver lesions (FLL), and to analyze the correlation of time-intensity curve (TIC) parameters between dynamic 3D-CEUS and two-dimensional CEUS (2D-CEUS). METHODS: Dynamic 3D-CEUS and 2D-CEUS were both carried out in 106 FLL cases with SonoVue. Divided into arterial, portal and late phases, dynamic 3D-CEUS image quality of 106 FLLs were scored by 2 readers separately and graded according to the overall score. The 2D-CEUS and identical 3D-CEUS TIC parameters of the same FLL were compared and the correlation of these parameters were analyzed. RESULTS: A satisfactory correlation (0.953) and a good inter-observer agreement (0.700) of 2 readers were achieved by using five-point score scale to image quality in 3 phases of dynamic 3D-CEUS. The boundaries of FLLs were clearest in arterial phase on dynamic 3D-CEUS. The depth and vascularization of FLLs only had influence on its image quality in only arterial phase (P = 0.002 and 0.000 respectively). The comparison of quantification between dynamic 3D-CEUS and 2D-CEUS of 56 FLLs were also underwent. Interclass correlation coefficient (ICC) of mean transit time (MTT) and time to peak (TP), were both 0.96, and Pearson correlation coefficients of all 5 TIC parameters were no less than 0.90 between dynamic 3D-CEUS and 2D-CEUS. CONCLUSION: Dynamic 3D-CEUS is technically feasible and can be used for clinical evaluation of the perfusion of FLL avoiding adverse factors of sampling. Quantitative 3D-CEUS parameters are stable and reliable, and have good correlation with those of 2D-CEUS.