TRANSJUGULAR INTRAHEPATIC PORTOSYSTEMIC SHUNT - US ASSESSMENT WITH MAXIMUM FLOW VELOCITY

PURPOSE: To evaluate the ability of Doppler ultrasonography (US) to de pict the patency of a transjugular intrahepatic portosystemic shunt (T IPS). MATERIALS AND METHODS: Twenty-eight patients were followed up af ter creation of TIPS with US, angiography, and endoscopy performed at regular intervals. Magnetic resonance (MR) angiography was performed i n four patients. US was performed first, and the results were correlat ed with those at angiography. Measurements of maximum flow velocity (V max) were taken from the proximal part of the shunt. RESULTS: In norma l shunts, mean Vmax was 95 cm/sec. Shunt obstruction was seen in 12 ca ses: occlusion in four and stenosis in eight. All cases of occlusion w ere detected with US and appeared as absent flow within the shunt. The re was one false-positive diagnosis of occlusion. All cases of stenosi s resulted in reduced Vmax (mean, 32 cm/sec; P <.001). After successfu l revision in seven patients, Vmax rose to a mean of 122 cm/sec. Artif act from the metal stent prevented flow assessment with MR imaging. CO NCLUSION: US can be performed to evaluate shunt status, and Vmax is an accurate noninvasive parameter for assessing shunt patency.