Gd-EOB-DTPA based magnetic resonance imaging for predicting liver response to portal vein embolization

AIM To evaluate the correlation between degree of kinetic growth(k GR) of the liver following portal vein embolization(PVE) liver and the enhancement of the during the hepatobiliary phase of contrast administration and to evaluate if the enhancement can be used to predict response to PVE prior to the procedure.METHODS Seventeen patients were consented for the prospective study.All patients had an MR of the abdomen with GdEOB-DTPA.Fourteen patients underwent PVE.The correlation between the kG R of the liver and the degree of enhancement was evaluated with linear regression(strong assumptions) and Spearman's correlation test(rank based,no assumptions).The correlation was examined for the whole liver,segments I,VIII,VII,VI,V,IV,right liver and left liver.RESULTS There was no correlation between the degree of enhancement during the hepatobiliary phase and kG R for any segment,lobe of the liver or whole liver(P = 0.19 to 0.91 by Spearman's correlation test).CONCLUSION The relative enhancement of the liver during the hepatobiliary phase with Gd-EOB-DTPA cannot be used to predict the liver response to PVE.

Magnetic resonance-based total liver volume and magnetic resonance-diffusion weighted imaging for staging liver fibrosis in mini-pigs

AIM:To determine whether and how magnetic resonance imaging(MRI)-based total liver volume(TLV) and diffusion weighted imaging(DWI) could predict liver fibrosis.METHODS:Sixteen experimental mature mini-pigs(6 males,10 females),weighing between 20.0 and 24.0 kg were prospectively used to model liver fibrosis induced by intraperitoneal injection of 40% CCl4 dissolved in fat emulsion twice a week for 16 wk,and by feeding 40% CCl4 mixed with maize flour twice daily for the subsequent 5 wk.All the survival animals underwent percutaneous liver biopsy and DWI using b = 300,500 and 800 s/mm2 followed by abdominal gadolinium-enhanced MRI at the 0,5th,9th,16th and 21st weekend after beginning of the modeling.TLV was obtained on enhanced MRI,and apparent diffusion coefficient(ADC) was obtained on DWI.Hepatic tissue specimens were stained with hematoxylin and Masson' s trichrome staining for staging liver fibrosis.Pathological specimens were scored using the human METAVIR classification system.Statistical analyses were performed to determine whether and how the TLV and ADC could be used to predict the stage of liver fibrosis.RESULTS:TLV increased from stage 0 to 2 and decreased from stage 3(r = 0.211;P < 0.001).There was a difference in TLV between stage 0-1 and 2-4(P = 0.03) whereas no difference between stage 0-2 and 3-4(P = 0.71).TLV could predict stage ≥ 2 [area under receiver operating characteristic curve(AUC) = 0.682].There was a decrease in ADC values with increasing stage of fibrosis for b = 300,500 and 800 s/mm2(r =-0.418,-0.535 and-0.622,respectively;all P < 0.001).Differences were found between stage 0-1 and 2-4 in ADC values for b = 300,500 and 800 s/mm2,and between stage 0-2 and 3-4 for b = 500 or 800 s/mm2(all P < 0.05).For predicting stage ≥ 2 and ≥ 3,AUC was 0.803 and 0.847 for b = 500 s/mm2,and 0.848 and 0.887 for b = 800 s/mm2,respectively.CONCLUSION:ADC for b = 500 or 800 s/mm2 could be better than TLV and ADC for b = 300 s/mm2 to pre-dict fibrosis stage ≥ 2 or ≥ 3.

Magnetic resonance imaging of portal vein invasion in hepatocellular carcinoma:A corroboration of 25 cases

AIMS Pre-operatively to assess tumor thrombus as- sociated with hepatocellular carcinoma in the portal vein. METHEDS Twenty-five patients diagnosed as hav- ing thrombus due to hepatocellular carcinoma were corroborated. MR imaging was perfomed with a 1.0T superconducting magnetic system. Both T1 and T2 weighed images and FLASH sequences were obtained in transverse plane. Additional FLASH images were ob- tained in coronal plane. RESULTS Thrombus in portal vein had a signal in- tensity similar to that of the main tumors. Intrinsic por- tal vein thrombus was in 16 patients. Six cases showed occlusive thrombus. Diffusely narrow portal branches were found in 3 patients. Portal venous thrombus showed an area of signal intensity which was replacing the normal flow void in the portal vein and showed a stumpy portal vein,irregular stenosis of portal vein and the formation of vascular net. CONCLUSION MRI was more sensitive and specific and a noninvasive method in detection of portal tumor thrombus used jointly with spin ech (SE) and gradient echo (GRE) techniques.