Advances in Hepatobiliary Imaging
Monday 20 April 2009
Room 316A 16:30-18:30


Elizabeth M. Hecht and Claude B. Sirlin

16:30  110. MR Elastography of Dynamic Postprandial Hepatic Stiffness Augmentation in Chronic Liver Disease
    Meng Yin1, Jayant A. Talwalkar2, Sudhakar K. Venkatesh3, Richard L. Ehman1
Department of Radiology, Mayo Clinic, Rochester, MN, USA; 2Division of Gastroenterology & Hepatology , Mayo Clinic, Rochester, MN, USA; 3Diagnostic Radiology, National University of Singapore, Singapore
    This preliminary investigation provides evidence that MRE-assessed hepatic stiffness in patients with chronic liver disease has a dynamic component that can increase following a test meal. This may reflect the transient increase in portal pressure that is known to occur in some of these patients postprandially. If confirmed, these findings will provide motivation for further studies to determine the potential value of assessing postprandial hepatic stiffness augmentation for predicting progression of fibrotic disease and the development of portal varices. The technique may also provide new insights into the natural history and pathophysiology of chronic liver disease.
16:42 111. Carbogen Gas-Challenge BOLD MRI in Rat Liver Fibrosis Model
    Ning Jin1,2, Jie Deng1,3, Tamuna Chadashvili4, Yue Zhang4,5, Yang Guo4, Guangyu Yang6, Reed Omary2,4, Andrew C. Larson1,2
Department of Radiology , Northwestern University, Chicago, IL, USA; 2Department of Biomedical Engineering, Northwestern University, Chicago, IL, USA; 3Department of Medical Imaging, Children's Memorial Hospital, Chicago, IL, USA; 4Department of Radiology, Northwestern University, Chicago, IL, USA; 5Department of Bioengineering, University of Illinois Chicago, Chicago, IL, USA; 6Department of Pathology, Northwestern University, Chicago, IL, USA
    Hepatic fibrosis is a dynamic and reversible process leading to regional and global blood perfusion alteration. We hypothesis that in the setting of liver fibrosis BOLD signal changes between normal and hyperoxia conditions would be reduced. In this work, a negative correlation was found between the BOLD response to gas-challenge and the degree of liver fibrosis. Gas-challenge BOLD MRI is a potential non-invasive method for liver fibrosis diagnosis and staging.
16:54 112. T1ρ-Based MR Imaging for the Non-Invasive Quantification of Extracellullar Matrix Protein Concentration in Hepatic Fibrosis
    Dania Daye1, Chenyang Wang, Eric Mellon2, Santosh Gaddam3, Rebecca Wells4, Emma Furth5, Ravinder Reddy3
Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA; 2Department of Biophysics and Molecular Biochemistry, University of Pennsylvania; 3Department of Radiology, University of Pennsylvania; 4Department of Medicine, University of Pennsylvania; 5Department of Pathology and Laboratory Medicine, University of Pennsylvania
    While hepatic cirrhosis is a major leading cause of adult death in the US, the gold standard to diagnose and monitor the progress of patients afflicted with this condition remains limited to liver biopsy. Biopsies, however, an often irreproducible and plagued with many complications. T1ρ-based MR imaging is a technique that has previously shown promise in quantifying macromolecular concentration. Given that liver fibrosis manifests as a progressive deposition of extracellular matrix proteins, we hypothesized that T1ρ imaging can be used to quantify protein deposition in fibrosis. Our preliminary results show that T1ρ imaging might have significant potential to provide for a quantitative and non-invasive assessment of hepatic fibrosis.
17:06 113.

In Vivo Assessment of Hepatic Ischemia/Reperfusion Injury in Rat Using Diffusion Tensor Imaging

    Jerry S. Cheung1,2, Shu Juan Fan1,2, April M. Chow1,2, Edward S. Hui1,2, Ke Xia Cai1,2, Kwan Man3, Ed X. Wu1,2
Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, China; 2Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, China; 3Department of Surgery, The University of Hong Kong, Hong Kong SAR, China
    Hepatic ischemia/reperfusion injury (IRI) occurs during liver transplantation, tumor resection, hemorrhagic shock and veno-occlusive disease, and is a major cause of acute liver failure. IRI in liver is also responsible for early organ failure and increased incidence of both acute and chronic rejection after liver transplantation. This study aims to examine the changes of diffusion measurements by diffusion tensor imaging (DTI). The experimental results demonstrated that DTI is useful in identifying hepatic IRI by characterizing the transient changes in mean diffusivity and fractional anisotropy.


17:18  114. Combined T2-Weighted and MRCP 3D Imaging of the Abdomen Using a Dual-Contrast Single-Slab 3D-TSE Pulse Sequence
    John P. Mugler, III1, Wilhelm Horger2, Berthold Kiefer2
Radiology, University of Virginia, Charlottesville, VA, USA; 2Siemens Healthcare, Erlangen, Germany
    This work explored the feasibility of acquiring both T2-weighted and MRCP images within the same 3D turbo-spin-echo (TSE) acquisition. By using a very long flip-angle train of up to 400 echoes that includes variable and constant flip-angle segments, T2-weighted and heavily T2-weighted (MRCP) high-resolution, 3D image sets of the abdomen were obtained with a single 3D-TSE acquisition in a clinically-acceptable acquisition time of 5-7 minutes. This approach has the potential to improve the quality and efficiency of diagnostic evaluation of the abdomen using MRI.


17:30 115. MRCP After the Injection of Gd-EOB-DTPA: Are 3 Minutes Safe for T2 Weighted Navigated 3D MRCP?
    Kristina Ringe1, R Gupta2, Angela Reichel1, Thomas Rodt1, Sabine Dettmer1, Nils Hellige3, Michael Galanski4, Elmar M. Merkle2, Joachim Lotz5
Department of Radiology, Hannover Medical School, Hannover, Germany; 2Department of Radiology, Duke University School of Medicine, Durham, NC, USA; 3Department of Radiology, Hannover Medical School, Hannover, Germany; 4Department of Radiology, Hannover Medical School, Hannover, Germany; 5Department of Radiology, Hannover Medical School, Hannover , Germany
    T2-weighted respiration navigated MRCP was performed before and 3.3+/-0.4min after administration of GD-EOB-DTPA in 21 patients. SNR in bile ducts was assessed to quantify alterations in the quality of MRCP induced by biliary excretion of the contrast agent. SNR decreased by 26.5 +/- 33.5% in the MRCP after the injection of GD-EOB. Maximal decrease of SNR was 90% making the MRCP non-diagnostic. A non-significant tendency for larger decreases of SNR in younger patients and preserved SNR in patients with parenchymal disease was seen.  GD-EOB-DTPA should be injected after a T2w-MRCP to avoid negative effects on the quality of the MRCP.
17:42 116. Combining Diffusion-Weighted MR Imaging with Gd-EOB-DTPA Enhanced MR Imaging Improves the Detection of Colorectal Liver Metastases

Dow-Mu Koh1, Toni Wallace1, Erica Scurr1, David J. Collins1,2, Angela Riddell1
Department of Radiology, Royal Marsden Hospital, Sutton, Surrey, UK; 2CR UK Clinical Magnetic Resonance Research Group, Institute of Cancer Research, Sutton, Surrey, UK

    The combination of diffusion-weighted MR imaging with Gd-EOB-DTPA enhanced T1-weighted MR imaging resulted in the highest diagnostic accuracy for the detection of colorectal liver metastases compared with either technique on its own. Combining both techniques appear to be optimum for defining the burden and distribution of liver metastases in patients with colorectal cancer to inform management strategies.


17:54 117. Ultra High Spatio-Temporal Resolution Hepatic MRI Using a Novel 2-Point Dixon Time Resolved 3D SPGR Sequence at 3T
    Manojkumar Saranathan1, Dan Rettmann1, Ersin Bayram2, Christine Lee3, James Glockner3
Applied Science Laboratory, GE Healthcare, Rochester, MN, USA; 2MR Engineering, GE Healthcare, Waukesha, WI, USA; 3Dept. of Radiology, Mayo Clinic, Rochester, MN, USA
    Dynamic contrast enhanced MRI (DCEMRI) is commonly used in abdominal-pelvic imaging for detection and characterization of primary and metastatic lesions. It affords adequate spatial resolution but the temporal resolution is often insufficient. Optimal timing of the contrast arrival is critical in capturing the arterial phases and in improving lesion conspicuity. Traditional fat suppression methods perform suboptimally at 3T due to Bo and B1 inhomogeneities, causing non-uniform fat suppression across the image and signal loss. We report clinical results of a novel DCEMRI technique called META (Multi-Echo Tricks Acquisition) that combines a multi-echo TRICKS scan with a two-point Dixon fat-water reconstruction algorithm to generate fat-only and water-only time resolved images at very high spatio-temporal resolution. META was scanned on 23 patients referred for hepatic MRI.
18:06 118. Diffusion-Weighted MR Imaging (DWI) Using TRacking Only Navigator Echo (TRON): Initial Clinical Evaluation and Comparison to Respiratory Triggered and Free Breathing DWI
    Thomas Kwee1, Taro Takahara1, Tetsuo Ogino2, Gwen Herigault3, Maarten van Leeuwen1, Willem Mali1, Peter Luijten1
Department of Radiology, University Medical Center Utrecht, Utrecht, Netherlands; 2Philips Healthcare, Tokyo, Japan; 3Philips Healthcare, Best, Netherlands
    Respiratory triggered (RT) and free breathing (FB) diffusion-weighted MR imaging (DWI) of the liver suffer from a prolonged examination time and image blurring, respectively. The TRacking Only Navigator echo (TRON) technique allows continuous real-time slice tracking and may be an excellent alternative. In this study, conspicuity of liver metastases (N=14) between TRON, RT, and FB DWI was equal, while actual scan time of RT DWI was two to three times longer and FB DWI inherently suffers from image blurring. Reproducibility of ADC measurements of liver metastases among TRON, RT and FB DWI was moderate to poor.
18:18 119. Clinical Liver MRI at 3.0 Tesla Using Parallel RF Transmission with Patient-Adaptive B1 Shimming
    Guido Matthias Kukuk1, Jürgen Gieseke1,2, Michael Nelles1, Roy König1, Magnus Andersson1, Eugen Muschler1, Petra Mürtz1, Jeroen Stout2, Marco Nijenhuis2, Frank Träber1, Nuschin Morakkabati-Spitz1, Daniel Thomas1, Christiane Katharina Kuhl1, Hans Heinz Schild1, Winfried Albert Willinek1
Department of Radiology, University of Bonn, Bonn, NRW, Germany; 2Philips Healthcare, Best, Netherlands

The clinical implementation of high field MRI systems has introduced new challenges for body imaging with respect to B1 field non-uniformities, generation of standing waves and signal loss particularly in abdominal imaging. To achieve a more homogeneous excitation we evaluated patient-adaptive RF shimming using parallel RF transmission for liver imaging in 22 patients at 3.0 Tesla. Our data demonstrate a significant improvement of image quality and lesion conspicuity in T2-TSE sequences and DWI.