ELECTRONIC POSTER - ismrm
ELECTRONIC POSTER - ismrm
ELECTRONIC POSTER - ismrm
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14:30 5113. Dipole Matched Filter with SWIFT<br />
Curtis Andrew Corum 1,2 , Djaudat Idiyatullin 1 , Steen Moeller 1 , Ryan Chamberlain 1 ,<br />
Michael Garwood 1,2<br />
1 Center for Magnetic Resonance Research, Dept. of Radiology, Medical School, University of Minnesota,<br />
Minneapolis, MN, United States; 2 Cancer Center, Medical School, University of Minnesota, Minneapolis, MN,<br />
United States<br />
The combination of the SWIFT sequence and a secular dipole matched filter give positive contrast at dipole sites.<br />
15:00 5114. Forward-Field Calculations Improve Contrast of Unwrapped MR Phase Images<br />
Martijn D. Steenwijk 1 , Maarten J. Versluis 2 , Mark A. van Buchem, Johan H C Reiber 1 ,<br />
Andrew Webb 2 , Julien Milles 1<br />
1 Division of Image Processing, Leiden University Medical Center, Leiden, Zuid-Holland, Netherlands; 2 CJ<br />
Gorter Center for High Field MRI, Department of Radiology, Leiden University Medical Center, Leiden, Zuid-<br />
Holland, Netherlands<br />
The aim of this work is to evaluate the gray matter / white matter (GM/WM) contrast improvement obtained by using forward-field<br />
calculations when unwrapping MR phase images of the brain. Standard phase unwrapping methods, such as high-pass filtering, prove<br />
sub-optimal in eliminating phase wraps with high spatial frequencies. Forward-field calculations can be used to compute geometrydependent<br />
artifact-corrected (GDAC) images in which the residual phase wrapping is reduced significantly. We applied this technique<br />
to a high-resolution T2*-weighted sequence at 7T to study its effects on GM/WM contrast. The GDAC technique results in a more<br />
favourable trade-off between unwrapping and GM/WM contrast.<br />
Thursday 13:30-15:30 Computer 126<br />
13:30 5115. Segmentation of the Structure of the Mouse Spinal Cord on DTI Images<br />
Michaël Sdika 1 , Virginie Callot 1 , Mathias Hebert 1 , Guillaume Duhamel 1 , Patrick J.<br />
Cozzone 1<br />
1 CRMBM/CNRS UMR6612, Faculté de médecine, Université de la Méditérranée, Marseille, France, France<br />
In this work, a fully automated method is proposed to segment the sub-structures of the mouse spinal Cord. WM/GM segmentation is<br />
used as input of the proposed method and on output, the GM substructures are distributed in Left Ventral and Dorsal GM and Right<br />
ventral and dorsal GM whereas substructures of WM were distributed into Left Lateral WM, Right Lateral WM, Ventral WM and<br />
Dorsal WM. The method has been evaluated by visual assessment and correlation with manual segmentation on 10 DTI images of<br />
mice acquired at 11.75T and show promising results.<br />
14:00 5116. Longitudinal Changes of White Matter Lesions<br />
Snehashis Roy 1 , Aaron Carass 1 , Navid Shiee 1 , Dzung L. Pham 2 , Susan Resnick 3 , Jerry L.<br />
Prince 1,2<br />
1 Electrical and Computer Engg, Johns Hopkins University, Baltimore, MD, United States; 2 Department of<br />
Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD, United States; 3 Laboratory of<br />
Personality and Cognition, National Institute on Aging, Baltimore, MD, United States<br />
Progression of white matter lesions are important for early detection and monitoring of diseases like Alzheimer's or Multiple Sclerosis.<br />
FLAIR images provide superior contrast for lesions compared to traditional T1 or T2 weighted images. But they are often not acquired<br />
for time and cost constraints. We developed an atlas based method to synthesize FLAIR images from T1 and T2 acquisitions. We use<br />
this method to quantify the progression of lesions on a pool of 20 subjects. Synthesizing FLAIRs can be seen as a potential way to<br />
reduce unnecessary data acquisition.<br />
14:30 5117. Accurate Adipose Tissue Segmentation from Single Gradient Echo Phase Images by<br />
Adaptive Local Thresholding<br />
Christian Würslin 1 , Frank Eibofner 1 , Fabian Springer 1 , Fritz Schick 1<br />
1 Department of Diagnostical and Interventional Radiology, Section on Experimental Radiology, University<br />
Hospital Tübingen, 72076 Tübingen, Germany<br />
In many applications, a quantification of fat is desired. Most (semi-)automatic procedures use T1-weighted spin echo images to<br />
accomplish this. These approaches are time-consuming and a precise quantification is usually complicated by a high amount of partial<br />
volume effects. We propose a quantification procedure based on one single phase image, acquired with a gradient echo technique and<br />
opposed-phase condition. This maximizes the contrast in between fat- and water- dominated tissues and is less time-consuming. The<br />
phase divergence, arising from inhomogeneities, is compensated for using an automated algorithm, enabling a precise fat<br />
quantification by thresholding. Phantom measurements show a high precision.<br />
15:00 5118. Improving Robustness of Cartilage Segmentation Using IDEAL Water and Fat<br />
Images<br />
Raghu Kokku 1<br />
1 MR SW & Apps , GTO-I, Wipro GE Healthcare, Bangalore, Karnataka, India<br />
Accurate and reliable quantification of cartilage volume in MRI is required for diagnosis of many degenerative and inflammatory<br />
diseases such as osteoarthritis or rheumatoid arthritis. A Novel approach to segment the anatomical structures and cartilage using