The comparative study of color doppler flow imaging, superb microvascular imaging, contrast-enhanced ultrasound micro flow imaging in blood flow analysis of solid renal mass

PURPOSES: To evaluate the value of Color Doppler Flow Imaging (CDFI), Superb Microvascular Imaging (SMI) and Contrast-enhanced Ultrasound Microflow Imaging (MFI) in display the microvascular blood flow signals in renal solid lesions. METHODS: 142 patients with 144 renal masses were examined by CDFI, SMI and MFI simultaneously. We compared the difference of blood flow grading and vascular architecture based on CDFI, SMI and MFI. RESULTS: The blood flow signals detection rates of CDFI, SMI and MFI were 78.5% (113/144), 88.9% (128/144) and 93.8% (135/144), respectively. Concentrated on blood flow grading, The coincidence rates of CDFI and SMI were 64.58% (93/144) and 81.25% (117/144) referring to MFI, respectively. Blood flow grade 2–3 in CDFI is significantly lower than SMI(x(2) = 5.557, P = 0.018) and MFI (x(2) = 10.165, P = 0.001). Whereas there was no significant difference between SMI and MFI (x(2) = 2.372, P = 0.499). Concentrated on vascular architecture, the coincidence rates of CDFI and SMI were 56.25% (81/144) and 75.69% (109/144) referring to MFI, respectively. Vascular architecture type IV and V in CDFI was significantly lower than SMI (x(2) = 18.217, P < 0.001) and MFI (x(2) = 29.518, P < 0.001). Whereas there was no significant difference between SMI and MFI (x(2) = 3.048, P = 0.550). The sensitivity and specificity of CDFI, SMI and MFI in the diagnosis of renal mass were 61.29% and 90.20%, 79.57% and 88.24%, 88.17% and 84.31% respectively. The areas under the ROC curve of the three were 0.757, 0.839 and 0.862, respectively. There was a statistically significant difference between CDFI and MFI (Z = 3.687, P = 0.0002), while there was no statistically significant difference between SMI and MFI (Z = 1.167, P = 0.2431). CONCLUSION: SMI and MFI are superior to CDFI in showing blood flow signals in renal solid masses, and it can perform blood flow and vascular architecture more accurately. ADVANCES IN KNOWLEDGE: SMI is similar to MFI in its ability to display fine vessels and diagnostic efficiency, and has application value in the diagnosis and differential diagnosis of renal solid masses.