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PURPOSE: Contrast enhanced magnetic resonance imaging (MRI) is able to assess liver function by characteristic changes of signal intensity (SI). The aim was to evaluate dynamic contrast-enhanced SI-indices of the abdominal aorta, portal vein and liver. METHODS: 72 patients underwent Gd-EOB-DTPA-enhanced MRI and a 13C-methacetin-based liver breath test (13C-MBT) for evaluation of liver function. Region-of-interest measurements in the liver, abdominal aorta and portal vein during native, arterial (AP), late arterial (LAP), portal venous (PVP) and hepatobiliary phase (HBP) were applied to analyze SI-indices in T1-weighted volume-interpolated breath-hold examination (VIBE) sequences with fat-suppression and relative enhancement (RE) analysis was performed. RESULTS: The liver (p < 0.001), the portal vein (p < 0.001) and abdominal aorta (p = 0.002) showed significant decrease of REs with decreasing liver function. An increasing trend between logarithmic values of 13C-MBT and REs of hepatic parenchyma (HBP; r = 0.662, p < 0.001), portal vein (PVP; r = 0.532, p < 0.001) and abdominal aorta (PVP; r = 0.421, p < 0.001) was observed. CONCLUSIONS: RE measurements of the hepatic parenchyma proofed to be a trustable evaluation method for liver function evaluation. In accordance with liver function, changes of REs in the portal vein and abdominal aorta occur. [ABSTRACT FROM AUTHOR]

BACKGROUND: The diagnostic value of Doppler ultrasonography of the portal vein for the evaluation of liver function is still contradictory. OBJECTIVE: Aim of this study was to test the relationship between clinical liver function tests based on MRI and breath testing and blood flow in the portal vein. METHODS: The portal vein velocity was measured by color coded Doppler ultrasonography (CCDS) and tested against the relative enhancement (RE), a MRI-based index of liver function. The signal intensity in the liver parenchyma was assessed before (pre) and after (post) administration of contrast agent, the RE was calculated afterwards. Further, the liver function was also assessed using a 13C-Methacetin-based breath test. The blood flow in the portal vein was tested for possible correlation applying Pearson's correlation coefficient. RESULTS: Using CCDS, all patients show a hepatopetal portal blood flow. The portal vein velocity is decreasing with progression of liver damage and there was a significant correlation of portal velocity with SI post (r = 0.411, p = 0.024). However, the portal velocity did not correlate significantly with the 13C-MBT readout (r = 0.233; p = 0.216), SI pre (r = 0.271, p = 0.147) or the relative enhancement (r = 0.303; p = 0.103). CONCLUSIONS: The results of this proof-of-principle study indicate that CCDS-based assessment of portal velocity is of only limited value for the evaluation of liver function. [ABSTRACT FROM AUTHOR]

Purpose: Contrast enhanced magnetic resonance imaging (MRI) is able to assess liver function by characteristic changes of signal intensity (SI).The aim was to evaluate dynamic contrast-enhanced SI-indices of the abdominal aorta, portal vein and liver., Methods: 72 patients underwent Gd-EOB-DTPA-enhanced MRI and a 13C-methacetin-based liver breath test (13C-MBT) for evaluation of liver function. Region-of-interest measurements in the liver, abdominal aorta and portal vein during native, arterial (AP), late arterial (LAP), portal venous (PVP) and hepatobiliary phase (HBP) were applied to analyze SI-indices in T1-weighted volume-interpolated breath-hold examination (VIBE) sequences with fat-suppression and relative enhancement (RE) analysis was performed., Results: The liver (p < 0.001), the portal vein (p < 0.001) and abdominal aorta (p = 0.002) showed significant decrease of REs with decreasing liver function. An increasing trend between logarithmic values of 13C-MBT and REs of hepatic parenchyma (HBP; r = 0.662, p < 0.001), portal vein (PVP; r = 0.532, p < 0.001) and abdominal aorta (PVP; r = 0.421, p < 0.001) was observed., Conclusions: RE measurements of the hepatic parenchyma proofed to be a trustable evaluation method for liver function evaluation. In accordance with liver function, changes of REs in the portal vein and abdominal aorta occur.