ELECTRONIC POSTER - ismrm

15:00 5134. Phase-Imaging Study in Restless Legs Syndrome
David Neil Manners 1 , Giovanni Rizzo 1,2 , Claudia Testa 1 , Caterina Tonon 1 , Roberto
Vetrugno 2 , Sara Marconi 2 , Giuseppe Plazzi 2 , Fabio Pizza 2 , Federica Provini 2 , Emil
Malucelli 1 , Bruno Barbiroli 1 , Pasquale Montagna 2 , Raffaele Lodi 1
1 Spectroscopy Unit, Department of Internal Medicine, Aging and Nephrology, Università di Bologna, Bologna,
BO, Italy; 2 Neurological Sciences, University of Bologna, Bologna, BO, Italy
Objectives. To apply phase imaging to the evaluation of brain iron content in patients with Restless Legs Syndrome. Methods. 11 RLS
patients and 11 controls were studied using gradient echo imaging, and localised and whole brain ROIs selected on derived phase
maps, sensitive to paramagnetic tissue. Results. In the whole brain analysis, RLS patients showed 10th and 90th percentile phase
values significantly different from controls. The 10th percentile for RLS patients correlated with disease duration. Conclusions. Whole
brain phase analysis is a suitable technique to study brain iron content and disclose reduced cerebral iron in RLS patients.
Magnetization Transfer
Hall B Monday 14:00-16:00 Computer 128
14:00 5135. Magnetization Transfer Contrast MRI in GFP-Tagged Live Bacteria
Valeria Righi 1,2 , Melissa Starkey 3 , George Dai 2 , Laurence G. Rahme 3 , A Aria Tzika 1,2
1 NMR Surgical Laboratory, Department of Surgery, Massachusetts General Hospital and Shriners Burns
Institute, Harvard Medical School, Boston, MA, United States; 2 Department of Radiology, Massachusetts
General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Boston,
MA, United States; 3 Molecular Surgery Laboratory, Department of Surgery, Massachusetts General Hospital
and Shriners Burns Institute, Harvard Medical School, Boston, MA, United States
We compared wild-type and GFP-tagged cells of Pseudomonas aeruginosa and Escherichia coli bacteria using MRI with
Magnetization Transfer Contrast (MTC). This method was sensitive enough to distinguish between GFP-tagged and non-tagged cells
at cell concentrations relevant to those used in animal infection models. The significance of this method is that it can be used to
visualize bacterial infections in vivo in real time without being restricted to the use of transparent tissue necessary for optical imaging.
This method provides a valuable tool to study the impact of novel antibacterial therapeutics.
14:30 5136. Enhancement of MT and CEST Contrast Via Heuristic Fitting of Z-Spectra
Moritz Wilhelm Zaiss 1 , Benjamin Schmitt 1 , Bram Stieltjes, Peter Bachert 1
1 Medical Physics in Radiology, DKFZ, Heidelberg, Germany
Magnetizations transfer processes are quantified by the evaluation of z-spectra. A superposition of Lorentzian line shape functions, a
solution of Bloch equations, is discussed as a heuristic but parametric model for z-spectrum fitting. Numerical, phantom and in vivo
studies demonstrate the functionality of this method which is less dependent on exact knowledge of the system and provides enhanced
contrast through parameter maps compared to standard asymmetry analysis. The heuristic fit is also less dependent on B 0
inhomogeneities and its parameters can be assigned to physical parameters such as concentration and transfer rates, which are markers
for tumour activity.
15:00 5137. A New, 3D GRE Based CEST Imaging Method for Clinical Application and
Verification with GagCEST in Articular Cartilage
Benjamin Schmitt 1 , Michael Bock 1 , Bram Stieltjes, Peter Bachert 1
1 Medical Physics in Radiology, German Cancer Research Center, Heidelberg, Germany
CEST imaging has been introduced as a new method to generate a various number of contrasts for MRI. However, the application of
CEST imaging for clinical application has so far been limited by extensive scan-times. These long scan times were necessary to
generate reproducible CEST images and often restricted to single-slice acquisitions. We introduce a new, 3D CEST imaging sequence
based on RF-spoiled gradient echo which can theoretically be used in a various number of CEST applications. The functionality is
exemplified using gagCEST to determine the vitality of knee cartilage in a 3D volume.
15:30 5138. A Comparison of Three CEST Imaging Methods
Zhongliang Zu 1 , Ke Li 1 , Daniel Frank Gochberg 1
1 Radiology, Vanderbilt University, Nashville, TN, United States
Three CEST imaging methods including continuous-wave, pulsed-, and spoiled gradient recalled CEST are numerically optimized and
compared using simulations and a creatine/agarose tissue phantom. We found that the average irradiation power is a more meaningful
sequence metric than is the average irradiation field; We also found that the SPGR-CEST provides an alternative to the EPI based
CW- and pulsed-CEST imaging methods that avoids the artifacts inherent to multi-echo acquisitions, though at the cost of lower CNR.