SONOGRAPHY OF TRANSJUGULAR INTRAHEPATIC PORTOSYSTEMIC SHUNTS - DETECTION OF ELEVATED PORTOSYSTEMIC GRADIENTS AND LOSS OF SHUNT FUNCTION

PURPOSE: To evaluate the role of ultrasound (US) in the detection of e levated portosystemic gradients and loss of shunt function in patients with a transjugular intrahepatic portosystemic shunt (TIPS). MATERIAL S AND METHODS: The authors' prospectively compared 151 Doppler hepatic sonograms with follow-up portal venograms in 64 patients with TIPS, S onographic data from within the portal system, hepatic arteries, and t hree areas within the TIPS were collected, Statistical analysis of the se parameters was used to establish the US criteria for shunt dysfunct ion. RESULTS: Midshunt velocity thresholds of less than 50 and less th an 60 cm/sec yielded sensitivities and specificities of 46% and 93%, a nd 57% and 89%, respectively, for the detection of portosystemic gradi ents exceeding 15 mm Hg, Use of a threshold midshunt velocity of less than 60 cm/sec or main portal vein velocity of less than 40 cm/sec rai sed the shunt dysfunction detection sensitivity to 86%, with a specifi city of 54%. CONCLUSION: Doppler US is an effective noninvasive screen ing tool for detecting elevated portosystemic gradients and evaluating the functional status of a TIPS, Midshunt velocities of less than 60 cm/sec or main portal vein velocities less than 40 cm/sec are a useful threshold for detecting shunt dysfunction.