Evaluation Of Stent Patency After TIPS Using Color Doppler And Contrast-enhanced Ultrasound

Objective:To evaluate the stent's patency after TIPS by combining color Doppler and contrast-enhanced ultrasound and to discusse the hemodynamic characteristics of the portal vein and stent after TIPS.Method:From September 2015 to November 2017,75 ultrasonographic examinations data of 33 patients who underwent TIPS because of portal hypertension in our hospital were analyzed.The equipment used in the study was TOSHIBA apilo-500 system with contrast-enhanced ultrasound software package.All the patients underwent color Doppler ultrasound first;the patients underwent contrast-enhanced ultrasound to observe and compared the stent patency between color Doppler and contrast-enhanced ultrasound when it was necessary.The measuring data included the width and flow velocity of portal vein trunk,the effective blood flow(contrast agent)widths of stent by color Doppler and contrast-enhanced ultrasound,the velocity of the portal vein site,the middle site and the hepatic vein site of the stent.All data were analyzed by SPSS Statistics 19.0.Statistical significance was defined as P<0.05.Results:1.In 47 examinations which underwent both color Doppler ultrasound and contrast-enhanced ultrasound,3 cases were diagnosed grade 0,6 cases were diagnosed grade 1,12 cases were diagnosed grade 2,26 cases were diagnosed grade 3 in color Doppler ultrasound examinations.1 case was diagnosed grade 0,0 cases were diagnosed grade 1,4 cases were diagnosed grade 2,42 cases were diagnosed grade in contrast-enhanced ultrasound examinations.Contrast-enhanced ultrasound was better than color Doppler ultrasound in stent flow imaging(P<0.05).2.In the cases whose stent patency was grade 3,the average width of portal vein trunk was 1.22±0.26 cm;the average flow velocity was 27.74±7.92 cm/s.The average effective blood flow(contrast agent)widths were 0.60±0.11 cm and 0.70±0.10 cm under the color Doppler and contrast-enhanced ultrasound examinations.The velocity range of the stent was 18.0-236.8cm/s,the average flow velocities of the stents portal vein site,the middle siteand the hepatic vein site were 71.52±36.84 cm/s,94.35±39.94 cm/s and 99.83±32.63 cm/s.There was a significant difference of blood flow velocities among different stent sites(P<0.05).Besides,the flow velocities of the hepatic vein site were higher than the portal vein site.Conclusion:1.Contrast-enhanced ultrasound was better than color Doppler ultrasound in stent flow imaging,combined these two examinations could improve diagnostic accuracy.2.There was certain regularity in the flow velocities of different sites of the stent;the flow velocities of the hepatic vein site were higher than the portal vein site.