High resolution flow (HR Flow) and Glazing Flow in cases of hepatic flow changes: Comparison to color-coded Doppler sonography (CCDS)

AIM: To evaluate the possibilities of flow detection using high resolution flow (HR Flow) and Glazing Flow technique in patients with liver parenchymal changes and flow changes in comparison to color-coded Doppler sonography (CCDS). MATERIAL AND METHODS: All examinations were performed using a multi frequency matrix convex probe with high resolution technique (SC6-1U/Resona7, Mindray, Shenzhen, China) by one experienced examiner to evaluate the venous, portal venous and arterial liver flow with digital documentation of the dynamic flow parameters like peak systolic flow, end-diastolic flow and resistance index. For liver parenchymal stiffness changes shear wave elastography was performed with at least 10 measurements. By two independent readers an elevation was performed to evaluate the image quality and the degree of flow artefacts, from 0 = not available to 5 points with excellent image quality without flow artefacts. RESULTS: All 40 patients (24 men, 16 women, age 27–83 years, mean 56±5 years) showed morphology changes from B-Mode of the liver parenchyma to inhomogeneous tissue with higher stiffness evaluated by the shear wave elastography (1.45 m/s up to 2.79 m/s±1.79 m/s, considering F1 up to F4 fibrosis) and in 15 cases histopathologically proven liver cirrhosis. In 9 cases after non-acute thrombosis flow reduction of the portal vein was the reason for the diameter less than 5 mm. Flow parameters for the venous flow were between 8 cm/s up to 29 cm/s, mean 14±4 cm/s, for the hepatic portal vein 5 cm/s up to 57 cm/s, mean 17±5 cm/s, for the hepatic artery systolic flow between 50 cm/s up to 127±33 cm/s, end-diastolic flow from 22 cm/s up to 47±8 cm/s. Resistance index for the hepatic artery was between 0.41 up to 0.73, mean 0.67±0.25. The image quality for CCDS over all cases was evaluated for CCDS between 1 up to 4. The mean quality was 2.5±0.5, for HR Flow in combination with Glazing Flow 3±0.5, with significant differences for the 2 readers (P < 0.01). CONCLUSION: Combination of HR Flow with Glazing Flow could be helpful to evaluate morphological und hemodynamic changes of liver arterial flow, portal venous and venous flow. Reduction of flow artefacts in combination with a higher image quality could be helpful for optimizing the digital measurements also for follow up examinations.