MR angiography in the postoperative evaluation of shunts for portal hypertension

This paper reports on MR angiography that was performed to evaluate patency of 31 shunts. MR angiography results were compared with results of angiography, Doppler, or MR imaging. Twenty-nine patients with histologically proved cirrhosis of the liver were studied. MR angiography was performed on a 1.5-T system with the two-dimensional inflow gradient-echo sequences (FFE) with 50/15, 60 degrees (TR/TE, RF pulse angle). Spatially selective presaturation pulses were acquired, and 40-60 sections covered a region of 20-30 cm. All MR angiograms were assessed for shunt patency and flow direction in the main portal vein. Satisfactory MR angiograms were obtained in all but two patients. Findings at MR angiography did not agree with those obtained with other imaging modalities and at surgery in six cases. MR angiography gives reliable and accurate information on portal venous anatomy and flow direction in patients with portal hypertension. It is a safe and noninvasive technique for detecting shunt patency. Sensitivity of this method is comparable with that of invasive angiography