Color Doppler combined with contrast-enhanced ultrasound in evaluation of stent patency after TIPS / 中国介入影像与治疗学

ABSTRACT

Objective: To observe stent patency after TIPS with color Doppler and contrast-enhanced ultrasound, and to analyze the hemodynamic characteristics of the stent. Methods: Postoperative ultrasonographic data of 32 patients underwent TIPS were retrospectively analyzed. The patency of stent was evaluated using color Doppler and contrast-enhanced ultrasound (defined into grade 0-3), and the flow velocities of the portal vein site, middle site and hepatic vein site of the stent were measured. Stent patency after TIPS was analyzed and compared between different ultrasound techniques, and the flow velocities in different sites of stent were compared in stents with excellent patency (grade 3). Results: There was significantly statistical difference of stent patency between color Doppler ultrasound and contrast-enhanced ultrasound (Z=-3.589, P<0.001). Contrast-enhanced ultrasound showed mild stenosis of stents (grade 2) in 8 times examination, severe stenosis (grade 1) in 6 times examination and stent occlusion in 2 times examination, while color Doppler ultrasound showed excellent patency (grade 3). There was significantly statistical difference of blood flow velocities among the portal vein site ([71.52±36.84]cm/s), middle site ([94.35±39.94]cm/s) and hepatic vein site([99.83±32.63]cm/s) of the stent (F=22.617, P<0.001). Besides, the flow velocitie of middle site (P=0.001) and the hepatic vein site (P<0.001) were respectively higher than that of portal vein site through pairwise comparison. Conclusion: Color Doppler combined with contrast-enhanced ultrasound can improve the accuracy of the evaluation of stent patency after TIPS. Significant difference of flow velocities exist in different sites of the stent.