Functional MRI of the Abdomen |
Thursday 23 April 2009 |
Room 316A |
13:30-15:30 |
Moderators: |
Harriet C. Thoeny and Thomas C. Lauenstein |
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13:30 |
659. |
Changes of Small Bowel
Peristalsis in Patients with Crohns Disease |
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Michael A. Patak1,
Christian Waldherr1, Christophoros
Stoupis2, Sukru Mehmet Erturk3,
John M. Froehlich1
1Institute of Radiology, Inselspital,
University Hospital, Bern, Switzerland; 2Kreisspital,
Männedorf, Switzerland; 3Dept of
Radiology, Sisli Etfal Hospital, Istambul, Turkey |
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Lesions of active Crohns
disease are often accompanied by motility disorders,
as has been described in fluoroscopy. Therefore, we
hypothesized that the addition of cine-MRE to static
MRE allows the detection of motility changes in CD
and helps to detect CD related lesions of the small
bowel wall. 40 consecutive patients with biopsy
proven CD were included retrospectively and assessed
for motility alterations using cine-MRE. Cine MRE
confirms localized small-bowel motility changes in
patients with clinically active Crohns disease.
Compared to standard MRE alone a significant
increase of active lesions was noted using cine MRE. |
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13:42 |
660. |
Evaluation of
Diffusion-Weighted MR Imaging for Detection of Bowel
Inflammation in Patients with Crohn`s Disease: A
Pilot Study |
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Aytekin Oto1,
Fang Zhu1, Kirti Kulkarni1,
Masatoshi Hori1, Arda Kayhan1,
Gregory S. Karczmar1, Jerrold R. Turner2,
David Rubin3
1Department of Radiology, The University of
Chicago, Chicago, IL, USA; 2Department of
Pathology, The University of Chicago, Chicago, IL,
USA; 3Department of Medicine, The
University of Chicago, Chicago, IL, USA |
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The purpose of this
study was to determine the feasibility of diffusion
weighted MR imaging (DWI) in detection of bowel
inflammation and investigate the changes in apparent
diffusion coefficient (ADC) values in the inflamed
bowel in Crohn`s disease. Eleven patients were
included. Two radiologists reviewed DWI images and
ADC maps to evaluate for inflammation in each bowel
segment and measured ADC values. Endoscopy and
pathology results were correlated with DWI findings.
The results showed DWI was a feasible technique for
detection of inflammation in patients with Crohn's
disease. ADC values were decreased in the inflamed
bowel segments indicating restricted diffusion. |
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13:54 |
661. |
Magnetic Resonance Imaging for
the Assessment of Gastro-Esophageal Junction |
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Jelena Curcic1,
Reto Treier1, Elad Kaufman2,
Zsofia Forras-Kaufman2, Mark Fox2,
Werner Schwizer2, Michael Fried2,
Peter Boesiger1
1Institute for Biomedical Engineering, ETH
Zurich, Zurich, Switzerland; 2Division of
Gastroenterology and Hepatology, University Hospital
Zurich, Zurich, Switzerland |
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Gastro-esophageal
junction (GEJ) is the main defense mechanism against
acid reflux. Its competence is the most fundamental
in preventing clinical manifestations of
gastro-esophageal reflux disease (GERD). Magnetic
resonance imaging (MRI) combined with
high-resolution manometry (HRM) as reference
technique was used to evaluate the structure and
function of the GEJ in healthy volunteers and GERD
patients. Anatomic and dynamic scans were performed
alternately before and after ingestion of a
high-caloric meal. GEJ area was reconstructed in 3D
and the insertion angle of the esophagus into the
stomach was calculated. On dynamic MR images reflux
events could be observed and analyzed. |
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14:06 |
662. |
Development and Positive
Contrast Imaging of an MR-Visible Mesh-Implant for
Repair of Abdominal Hernia |
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Nils A. Kraemer1,
Jens Otto2, Michael Hodenius3,
Ioana Slabu3, Martin Baumann3,
Uwe Klinge2,3, Andreas Muellen4,
Boris Obolenski4, Rolf W. Guenther1,
Gabriele A. Krombach1
1Diagnostic Radiology, University Hospital
Aachen, Aachen, Germany; 2Department of
Surgery, University Hospital Aachen, Germany; 3Helmholtz
Institute for Applied Medical Engineering,
University of Technology Aachen, Germany; 4FEG
Textiltechnik Forschungs- und
Entwicklungsgesellschaft mbH, Aachen, Germany |
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Polymer meshes are
frequently implanted for surgical treatment of
hernia. As, these meshes cannot be depicted with
conventional radiological methods, aim of this study
was to develop an MR-visible mesh implant. After
incorporating superparamagnetic nanoparticles of
ferrofluids into the mesh-filaments, susceptibility
artefacts enabled delineation of the mesh. As
intra-abdominal air and scar tissue present with
hypointense signal intensities too, positive
contrast of these susceptibilities was achieved by
using inversion-recovery with ON-resonant water
suppression (IRON) sequences. In phantoms and animal
corps, the ferrous mesh was clearly
delineated using IRON-imaging. Consequently, this
method can help to reveal frequent post-surgery mesh
related problems. |
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14:18 |
663. |
Functional Monitoring of Small
Bowel Motility: Comparison of Spasmolysis Induced by
Glucagon or Buscopan |
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John M. Froehlich1,
Muriel Daenzer1, Constantin von Weymarn1,
Sukru Mehmet Erturk2, Christoph L.
Zollikofer3, Michael A. Patak1
1Institute of Radiology, Inselspital,
University Hospital, Bern, Switzerland; 2Dept
of Radiology, Sisli Etfal Hospital, Istambul,
Turkey; 3Institute of Radiology,
Kantonsspital, Winterthur, Switzerland |
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Cross-sectional imaging
of the abdominal organs suffers from peristaltic
movement artifacts justifying the administration of
spasmolytic drugs prior to imaging. Buscopan or
glucagon, are being used in the large majority of
cases. In this prospective clinical MR study we
characterized and compared intraindividually the
pharmacological profile of the two drugs by
measuring the small-bowel cross-sectional diameter
over time. While paralysis was reached rapidly with
both drugs, glucagon was more reliable in achieving
a complete arrest and lasted roughly three times
longer than Buscopan. MRI is a reliable and
reproducible method to quantify and analyze small
bowel motility. |
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14:30 |
664. |
DTI of the Kidney at 3T -
Protocol Evaluation, Reproducibility and Comparison
to 1.5T |
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Mike Notohamiprodjo1,
Annie Horng1, Ulrike Attenberger1,
Olaf Dietrich1, Henrik J. Michaely2,
Karin A. Herrmann1, Maximilian F. Reiser1,
Christian Glaser1
1Institute for Clinical Radiology, University
Hospitals Munich, Munich, Bavaria, Germany; 2Institute
for Clinical Radiology, University Hospital,
Mannheim, Bavaria, Germany |
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The purpose of this
study was to assess the feasibility of DTI of the
kidney at 3T. Mean Fractional Anisotropy (FA)-values
at 3T were not significantly different to
1.5T-measurements. Signal-to-noise-ratio and
contrast-to-noise-ratio for cortex and medulla were
significantly higher at 3T. However, medullary FA
was less reproducible than FA of the cortex and
1.5T-measurements provided slightly lower Apparent
diffusion coefficient (ADC)-values. For calculation
of FA, acquisition of 2 b-values and 6
diffusion-directions appeared sufficient. DTI of the
kidney may become a valuable tool for studying renal
microarchitecture, however a certain field-strength
associated variability and varying reproducibility
should be considered. |
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14:42 |
665. |
Diffusion-Weighted Imaging for
the Diagnosis of Bland Versus Tumor Thrombosis in
the Portal and Renal Veins |
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Jignesh M. Patel1,
Elizabeth M. Hecht1, Danny C. Kim1,
James S. Babb1, Bachir Taouli1,
Ruth P. Lim1
1Radiology, NYU Langone Medical Center, New
York, NY, USA |
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Differentiating bland
from tumor thrombus is essential for appropriate
management. We assessed the diagnostic performance
of DWI for the differentiation of bland versus tumor
thrombus in renal and hepatic malignancies. The
ability to distinguish bland from tumor thrombus on
high b-value DWI images was significant with an
overall sensitivity, specificity, NPV and PPV of
0.87, 0.89, 0.73 and 0.95 respectively. In addition,
the mean ADC was significantly lower in tumor
thrombus (1.16 x 10-3 mm2/sec) when compared to
bland (1.71 x 10-3 mm2/sec), p< 0.001. |
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14:54 |
666. |
Differentiation of Pancreas
Carcinoma from Healthy Pancreatic Tissue Using a
Wide Range of B-Values: Comparison of ADC and IVIM
Parameters |
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Andreas Lemke1,
Lothar Rudi Schad1, Frederik Laun2,
Bram Stieltjes3
1Chair in Computer Assisted Clinical Medicine,
University of Heidelberg, Faculty of Medicine,
Mannheim, Germany; 2Department of Medical
Physics in Radiology, German Cancer Research Center,
Heidelberg, Germany; 3Department of
Radiology, German Cancer Research Center,
Heidelberg, Germany |
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DWI was performed to
determine changes of diffusion and microperfusion in
healthy pancreatic tissue and pancreatic cancer
using the IVIM-approach. The perfusion fraction f,
the diffusion coefficient D and the pseudo diffusion
coefficient D* were extracted from six healthy
volunteers and six patients with histologically
proven pancreatic carcinoma and were compared to ADC
values. The perfusion fraction in pancreatic
carcinoma was significantly lower than in healthy
pancreatic tissue (p=0.002) in contrast to D and D*
(p>0.5). Also, f was more sensitive then the low
b-value ADC (p=0.008). The high b-value ADC showed
no significant difference (p=0.064) between the two
groups. |
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15:06 |
667. |
Longitudinal Assessment of
Renal Fibrosis by Diffusion Weighted MRI: A Study in
Unilateral Ureteral Obstruction (UUO) Mice Model |
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Osamu Togao1,
Shigehiro Doi2, Makoto Kuro-o2,
Masaya Takahashi1
1Advanced Imaging Research Center, University
of Texas Southwestern Medical Center, Dallas, TX,
USA; 2Pathology, University of Texas
Southwestern Medical Center, Dallas, TX, USA |
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Renal fibrosis is the
final common pathology of most progressive renal
disease such as diabetic nephropathy and
glomerulonephritis. Renal fibrosis has been widely
investigated in an established animal model with
unilateral ureteral obstruction (UUO). In the
present study, we investigated the progression of
the renal fibrosis in the animal model
longitudinally by T2-weighted imaging (T2WI) and
diffusion weighted imaging (DWI) to test whether MRI
could provide metrics for detection and evaluation
of the severity of renal fibrosis. |
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15:18 |
668. |
Diffusion Tensor Imaging of
Renal Ischemia/Reperfusion Injury |
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Jerry S. Cheung1,2,
Shu Juan Fan1,2, April M. Chow1,2,
Ed X. Wu1,2
1Laboratory 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 |
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Renal
ischemia/reperfusion injury (IRI) is a major cause
of acute renal failure in native and in transplanted
kidneys. IRI in kidney associated with
transplantation may also influence early graft
function and late changes. Recently, anisotropy
measurement with diffusion tensor imaging (DTI) has
been found to provide additional information about
functional and structural status of kidney. In this
study, we aim at characterizing diffusion properties
of kidney with mean diffusivity (MD) and fractional
anisotropy (FA) in an experimental rat model of
renal IRI. The experimental results demonstrated
that DTI is useful in identifying renal IRI by
characterizing the changes in MD and FA. |
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