TRADITIONAL POSTER - ismrm

Poster Sessions
2329. Direct Visualization of Surgical DBS Targets Using High-Field (7T) MRI
Noam Harel 1 , Essa Yacoub 2 , Kamil Ugurbil 2 , Aviva Abosch 3
1 Radiology, University of Minnesota, Minneapolis, MN, United States; 2 Radiology , University of Minnesota, Minneapolis, MN,
United States; 3 Neurosurgery, University of Minnesota, Minneapolis, MN, United States
Deep brain stimulation (DBS), a surgical treatment involving the implantation of an electrode in the brain, is used for the treatment of patients with
movement disorders. The success of this surgical technique is critically dependent on precise placement of the DBS electrode into the target structure.
However, current clinical imaging methods lack the sensitivity for resolving and visualizing of the DBS target.
Here, using a combination of high magnetic field (7T) with susceptibility-weighted contrast resulted in a dramatically improved ability to identify and
delineate anatomical architecture of deep brain structures that are FDA-approved DBS targets.
2330. Human T 2 * and Phase Imaging at 9.4 T
Juliane Sabine Budde 1 , Gunamony Shajan 1 , Jens Hoffmann 1 , Frank Muehlbauer 1 , Kâmil Ugurbil 2 , Rolf
Pohmann 1
1 Max Planck Institute for Biological Cybernetics, Tuebingen, Germany; 2 Center for Magnetic Resonance Research, University of
Minnesota, Minneapolis, United States
Ultra-high static magnetic field causes higher susceptibility effects which yield shorter T2* values and larger variations of the image phase. In this work, we
acquired highly detailed T2* maps showing internal structures. Mean T2* values for GM were estimated as 28ms±6ms and 20ms±4ms for WM. Phase
images were post-processed to yield images with high tissue contrast between grey and white matter throughout the brain at a resolution of 200µm x 200µm
x 1mm. Signal gain at ultra-high field allows for high resolution surface phase images of 130µm x 130µm in-plane resolution. In these, differences within
grey matter are visible.
2331. Ultra-High Field MRI at 7.0 Tesla in Patients with Ischemic or Hemorrhagic Stroke: A Preliminary
Study
Anja Gwendolyn van der Kolk 1 , Jaco JM Zwanenburg 1 , Geert Jan Biessels 2 , Fredy Visser 1,3 , Peter R.
Luijten 1 , Jeroen Hendrikse 1
1 Department of Radiology, University Medical Center, Utrecht, Netherlands; 2 Department of Neurology, University Medical Center,
Utrecht, Netherlands; 3 Philips Healthcare, Best, Netherlands
Seven patients with clinically and standard imaging-based proven ischemic or hemorrhagic stroke were scanned with magnetization prepared 3D FLAIR,
combined time-of-flight inflow and multi-echo fast field echo (meFFE), T 1 3D TFE, and DTI. 7.0 Tesla results were comparable to results of similar 1.5
Tesla sequences, but with better resolution and – in 3 out of 7 patients – additional information regarding underlying pathology. Furthermore, meFFE with 3
echoes was valuable in identification of microbleeds, microinfarcts and thrombus.
General Brain Imaging: Technique Development
Hall B Wednesday 13:30-15:30
2332. Multicontrast 3D Structural Imaging to Improve Automatic Brain Extraction and Segmentation
Bradley P. Sutton 1,2 , Anh Tu Van 3
1 Bioengineering, University of Illinois, Urbana, IL, United States; 2 Beckman Institute, University of Illinois, Urbana, IL, United
States; 3 Electrical and Computer Engineering, University of Illinois, Urbana, IL, United States
Currently many structural neuroimaging studies rely only on a T1-weighted image for brain extraction. Additional image contrast like T2 may improve the
performance of the automatic brain extraction procedure. In this work, a previously proposed multiparametric 3D structural imaging sequence that provides
several volumes with varying contrast in a multi-echo acquisition is used to assist in automatic brain segmentation. Two 3D volumes (one T1-weighted and
one T2-weighted) with 1.2 mm isotropic resolution and a low resolution 3D field map were obtained simultaneously within 6.5 minutes. Improvement in
brain extraction utilizing the additional contrast was observed.
2333. PROPELLER Using Parallel Imaging with Across Blade Calibration for T1 FLAIR
James H. Holmes 1 , Philip J. Beatty 2 , Howard A. Rowley 3,4 , Zhiqiang Li 5 , Ajeetkumar Gaddipati 6 , Xiaoli
Zhao 6 , Reed F. Busse 1 , Jean H. Brittain 1
1 Applied Science Laboratory, GE Healthcare, Madison, WI, United States; 2 Applied Science Laboratory, GE Healthcare, Menlo Park,
CA; 3 Radiology, University of Wisconsin-Madison, Madison, WI, United States; 4 Neurological Surgery, University of Wisconsin-
Madison, Madison, WI, United States; 5 GE Healthcare, Phoenix, AZ; 6 GE Healthcare, Waukesha, WI, United States
A novel parallel imaging technique for PROPELLER that utilizes external calibration data as well as a small amount of internal calibration data per blade is
demonstrated for T1 FLAIR imaging. Short echo trains, which are optimal for T1 imaging, are maintained while the effective blade width is increased by
reducing the number of internal calibration lines. Wider blades enable motion to be detected and corrected more reliably, improving robustness in
uncooperative patients. The method is validated in studies of volunteers instructed to move their head during the acquisition.