TRADITIONAL POSTER - ismrm

Poster Sessions
the study of large heterogeneous lesions, but shimming a large volume in the head and neck is challenging due to large susceptibility differences. We
employed an anti-susceptibility device to improve the local field homogeneity. We examined 13 patients using this technique and we showed that CSI is
feasible in the head and neck.
2413. 3D Mapping of Vocal Fold Geometry During Articulatory Maneuvers Using Ultrashort Echo Time
Imaging at 3.0 T
Tobias Frauenrath 1 , Andreas Goemmel 2 , Christoph Butenweg 2 , Mario Otten 3 , Thoralf Niendorf 1,4
1 Berlin Ultrahigh Field Facility, Max-Delbrueck Center for Molecular Medicine, Berlin, Germany; 2 Chair of Structural Statics and
Dynamics, RWTH, Aachen, Germany; 3 Erich-Thienhaus-Institute, Hochschule für Musik, Detmold, Germany; 4 Experimental and
Clinical Research Center (ECRC), Charité Campus Buch, Humboldt-University, Berlin, Germany
Even if some spatial insight can be obtained by stereoscopy imaging from classical optical methods or ex-vivo experiments, real 3D in-vivo measurements
of vocal fold geometry are still elusive. Magnetic resonance imaging (MRI) is conceptually appealing for the pursuit of 3D imaging since it affords submillimeter
spatial resolution and versatile tissue/muscle/cartilage image contrast. However, MRI comes with the penalty that it requires relatively long scan
times. Hence, imaging of moving organs requires consideration of physiological motion. For the phonating vocal folds, periodic oscillation is superimposed
by breathing movements (abduction and adduction). While for the first, synchronization cannot be obtained yet, the second can be handled by a customized
explicit synchronization technique. The imaging protocol consisted of segmented 3D gradient-echo imaging and segmented 3D ultra-short TE. In vivo
imaging on male and female subjects was conducted using a 3.0T in modal and head register. 3D MRI data were included into segmentation to derive
boundary conditions for finite-element models of vocal fold oscillation. Thereby, the segmented air volume of the larynx is transformed in splines at
different positions in the anterior-posterior axis of the vocal folds.
2414. MR Elastography of the Ocular Vitreous Body
Daniel V. Litwiller 1 , Yogesh Mariappan 1 , Richard L. Ehman 1
1 Mayo Clinic, Rochester, MN, United States
The gradual liquefaction of the ocular vitreous body with age can lead to retinal detachment and loss of sight. Although retinal detachment is a simple
condition to diagnose, historically, means to evaluate the mechanical properties of the vitreous body have been invasive and technically challenging. The
development of a reliable, noninvasive measurement technique would improve our understanding of the underlying physiology of this condition, and aid in
evaluating patients and potential treatments. The purpose of this work was to investigate the utility of MR elastography as a noninvasive means to quantify
the viscoelastic properties of the vitreous body.
2415. Parotid Sparing Volume-Dependent Perfusion Characteristics of Acute Radiation Injury: Investigated
by Fat-Saturated Dynamic Contrast-Enhanced MRI
Cheng-Chieh Cheng 1 , Chun-Jung Juan 2 , Hsiao-Wen Chung, 2,3 , Yee-Min Jen 2 , Su-Chin Chiu 1 , Hing-Chiu
Chang, 1,4 , Hui-Chu Chiu 5,6 , Cheng-Hsien Hsu 2,7 , Guo-Shu Huang 2 , Cheng-Yu Chen 2
1 Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei, Taiwan; 2 Department of
Radiology, Tri-Service General Hospital, Taipei, Taiwan; 3 Department of Electrical Engineering, National Taiwan University, Taipei,
Taiwan; 4 Applied Science Laboratory, GE Healthcare Taiwan, Taipei, Taiwan; 5 Department of Nuclear Medicine, Tri-Service General
Hospital, Taipei, Taiwan; 6 EMBA in Global Chinese Management, Department of Business Administration, Tamkang University,
Taipei, Taiwan; 7 Division of Software Design, Notebook Unit 5, Quanta Computer Inc., Taipei, Taiwan
Parotid glands are highly radiosensitive, while the utilization of parotid sparing technique decreases the irradiation, and thus may reduce radiation therapy
damage. In this study, we demonstrate a graded alteration in the perfusion characteristics of parotid glands, with the respect of parotid-sparing volume
provided by the intensity modulated radiotherapy (IMRT) technique.
2416. High-Resolution Imaging of the Laryngeal Cartilages: Volunteer and Cancer Patient Studies
Joëlle Karine Barral 1 , R. Reeve Ingle 1 , Edward J. Damrose 2 , Nancy J. Fischbein 2,3 , Dwight G. Nishimura 1
1 Electrical Engineering, Stanford University, Stanford, CA, United States; 2 Otolaryngology, Stanford University, Stanford, CA,
United States; 3 Radiology, Stanford University, Stanford, CA, United States
Current staging of laryngeal cancer and choice of optimal treatment are hindered by the difficulty of accurately assessing cartilage invasion. The use of a
dedicated three-channel array instead of the conventional eight-channel neuro-vascular array allows a reduction in voxel size by a factor of 20. A low-order
polynomial fitting approach is used to compensate for the coil sensitivity profile. In healthy volunteers, the increased resolution makes visible the delineation
of non-ossified cartilage, otherwise indistinguishable from muscle. The dedicated array is also used in cancer patients, and improvement in image quality is
demonstrated.
2417. Brain Structural Changes Underlying Cognitive Disabilities in Patients with Obstructive Sleep Apnea
Syndrome (OSAS): A VBM Study
Giovanni Giulietti 1,2 , Federico Torelli 1,3 , Marco Bozzali 1 , Girolamo Garreffa 1,2 , Nicola Moscufo 4 , Silvana
Zannino 1,5 , Laura Serra 1 , Fabio Placidi 5 , Fabrizio Fasano 1 , Gisela Hagberg 1 , Bruno Maraviglia 1,2 , Ina
Djonlagic 6 , Julian Saboisky 6 , Atul Malhotra 6 , Maria Grazia Marciani 1,5 , Charles Guttmann 4
1 IRCCS "Santa Lucia Foundation", Rome, Italy; 2 "Enrico Fermi" Center, Rome, Italy; 3 Center for Neurological Imaging, Brigham and
Women's Hospital, Harvard Medical School, Boston, United States; 4 Center for Neurological Imaging, Brigham and Women's
Hospital, Harvard Medical School, Boston, United States; 5 Department of Neuroscience, University "Tor Vergata", Rome, Italy;
6 Division of Sleep Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, United States
This VBM study aims at investigating GM and WM changes which might account for clinical disabilities in patients with OSAS. Sixteen patients with
OSAS (grouped in moderate and severe clinical stage) and 14 healthy controls were investigated. Neuropsychological assessment and MRI scanning were
obtained from each subject. Patients reported a selective impairment of verbal memory. Subjects with severe OSAS showed a bilateral GM atrophy of the