TRADITIONAL POSTER - ismrm

Poster Sessions
2642. Reproducibility Evaluation of Liver Metabolite Parameters: 1 H Decoupled - 31 P MRSI of Normal
Volunteers at 1.5T
Jing Qi 1 , Amita Shukla-Dave 1 , Jason Koutcher 1 , Mithat Gönen 2 , Yuman Fong 3 , Lawrence H. Schwartz 4 ,
Kristen L. Zakian 5
1 Medical Physics, Memorial Sloan-Kettering Cancer Center; 2 Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer
Center; 3 Surgery, Memorial Sloan-Kettering Cancer Center; 4 Radiology, Sloan-Kettering Cancer Center; 5 Medical Physics, Memorial
Sloan-Kettering Cancer Center, New York, NY, United States
In order to evaluate reproducibility of liver metabolites measured by 1 H decoupled- 31 P MRSI technique, 13 normal subjects were investigated twice at 2
weeks interval. Concentration of PE, PC, PME, Pi, GPE, GPC, PDE and NTP were calculated. Inter- and intra- subject variations were analyzed. Inter- and
intra-subject coefficient variation ranged from 11% to 25 % for all metabolite concentration. Intra-subject reproducibility was not superior to inter-subject
reproducibility, indicating that the random biological differences don’t seem to exceed the differences generated by technical variation in normal volunteers.
Both technical and biological factors should be considered when interpret liver 31 P MRSI data.
2643. Comparison of Two Strategies to Improve Quality of in Vivo 1H MR Spectra in the Presence of Motion
Michael Germuska 1 , Jian Xu 2 , Martin Leach 1 , Geoffrey Payne 1
1 CR-UK and EPSRC Cancer Imaging Centre, Institute of Cancer Research and Royal Marsden Hospital, Sutton, London, United
Kingdom; 2 Siemens Healthcare U.S., New York, NY, United States
In vivo 1H MR spectroscopy has proved valuable for evaluating tumours. However, acquisition of spectra in the abdomen is complicated by respiratory
motion. The motion degrades the spectral quality by phase and frequency distortions and by modification of the PSF. We compared two approaches to
combat motion in liver spectroscopy. The first utilises a post-processing approach to correct phase and frequency distortions, the second employs prospective
gating when acquiring the data. Both techniques showed an improvement in linewidth and SNR compared to free-breathing acquisitions. The postprocessing
methodology showed an advantage in SNR due to the increased number of signal averages.
2644. Ω-3 Fatty Acid Detection by L-COSY in Human Bone Marrow at 3T
Saadallah Ramadan 1 , Robert V. Mulkern 2 , Carolyn E. Mountford 1
1 Radiology, Brigham and Women's Hospital, Boston, MA, United States; 2 Radiology, Children’s Hospital, Boston, MA, United States
3 is an essential fatty acid (FA) that cannot be synthesized in the body and is obtained by diet. In the human body, essential FA serve multiple functions
including neuroprotective functions, mood, behavior and prevents inflammation. There are two types of £s-3 FAs: eicosapentaenoic acid (EPA)
docosahexaenoic acid (DHA), both of these molecular structures end with R-HC=CH-CH2-CH3. We investigated possibility of detecting č-3 in human
bone marrow, at 3T, using localised one dimensional (1D) (PRESS) and localized two-dimensional (2D) correlation spectroscopy (L-COSY).
Body Diffusion
Hall B Wednesday 13:30-15:30
2645. Effect of Region of Interest Position on Liver Apparent Diffusion Coefficient.
Daniel Wilson 1 , J. Ashley Guthrie 2 , Janice Ward 2
1 Medical Physics, Leeds Teaching Hospitals NHS Trust, Leeds, West Yorkshire, United Kingdom; 2 Radiology, Leeds Teaching
Hospitals NHS Trust, Leeds, West Yorkshire, United Kingdom
The liver ADC was measured in 3 different positions in the liver in 33 subjects. The mean ADC was signficantly different between the 3 different positions.
This is attributed to the presence of noise in the middle of the liver and artefactual signal loss at high b-values at superior positions in the left lobe. Care must
be taken when measuring ADC in the liver.
2646. Continuously Moving Table Whole-Body MRI Using Variable Field of View
Robert L. Janiczek 1,2 , Jonathan W. Howard 2 , Giulio Gambarota 2 , John S. Thornton 1 , Xavier Golay 1 ,
Rexford D. Newbould 2
1 Institute of Neurology, University College London, London, United Kingdom; 2 GSK Clinical Imaging Centre, London, United
Kingdom
Continuously moving table (CMT) acquisitions have been proposed whereby data are collected in a hybrid space as the patient moves through the scanner.
In CMT acquisitions the table velocity and therefore scan duration is proportional to the in-plane FOV. This work investigates the use of varying the FOV as
a function of patient position in order to reduce scan time. A low-resolution scout scan is used to design a k-space sampling pattern that matches the minimal
FOV requirement. The use of a variable FOV CMT acquisition is shown to reduce scan time by 32% over a conventional constant FOV design.
2647. Diffusion-Weighted Imaging of the Abdomen with Readout-Segmented (RS)-EPI
Samantha J. Holdsworth 1 , Stefan Skare 1 , Shreyas S. Vasanawala 1 , Roland Bammer 1
1 Radiology, Stanford University, Palo Alto, CA, United States
Diffusion-weighted imaging (DWI) in the abdomen has proven useful for the various pathologies including liver lesion characterization and diagnosis of
diffuse renal disease. However, image distortions arising from the use of EPI has shown to be problematic. In this work we explore the use of readoutsegmented
(RS)-EPI for DWI of the abdomen and show that it may be a useful method for reducing geometric distortion and blurring.