ELECTRONIC POSTER - ismrm

performed to validate each of these steps. Device localization and MR tracking was validated in a phantom, and an ablation was
performed in another phantom with multi-slice thermometry and ROI feedback. The platform successfully measured temperature
rises and relayed that data to external power control software that regulated the ablation.
14:30 4121. Towards Real-Time Tracking of Anatomic Features for HIFU Beam Steering
David A. Hormuth 1,2 , Brian J. Zappia 2 , Andrew B. Holbrook 3 , Kim Butts-Pauly 3 , Charles
L. Dumoulin 2
1 Biomedical Engineering, Rose Hulman Institute of Technology, Terre Haute, IN, United States; 2 Imaging
Research Center, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States; 3 Radiology,
Stanford University, Stanford, CA, United States
Software for identifying and following anatomic features during real-time imaging was developed. This software was tested in realtime
images of the liver during free breathing. It was able to successfully locate and follow the diaphragm and selected blood vessels
within the liver during free breathing. These feature locations were used to generate the coordinates of an arbitrary target within the
liver with sufficient speed and robustness to provide real-time offsets to a HIFU beam. It is anticipated that these algorithms will
permit real-time ablation of liver lesions using HIFU during free-breathing and overcome the difficulties associated with breath held
approaches.
15:00 4122. MRI-Based Temperature Analysis of Transcranial MRI-Guided Focused
Ultrasound Surgery for Functional Neurosurgery
Nathan McDannold 1 , Beat Werner 2 , Daniel Jeanmonod 3 , Eyal Zadicario 4 , Rita Schmidt 4 ,
Ernst Martin 2
1 Radiology, Brigham & Women's Hospital/Harvard Medical School, Boston, MA, United States; 2 MR-Center,
University Children’s Hospital Zurich, Zurich, Switzerland; 3 Department of Functional Neurosurgery,
University Hospital Zurich, Zurich, Switzerland; 4 InSightec, Ltd., Tirat Carmel, Israel
This work used MR temperature imaging (MRTI) to evaluate focal and skull-induced heating in nine patients treated for neuropathic
pain in order to characterize the safety profile of a Transcranial MRI-guided Focused Ultrasound system. The ratio between focal and
skull-induced heating was 11.3 using a conservative approach, approximately 2.7 times higher than in previous tests of an earlier version
in glioblastoma patients, presumably due to improvements in the system, MRTI, and differences in target location. These results
suggest an improved treatment window that can potentially increase the volume of the brain that can be safely targeted by the system.
15:30 4123. Focal Spot Visualization in MRgFUS of the Breast: MR-ARFI Vs. T1-Weighted
FSE
Elena Kaye 1,2 , Rachel Rinat Bitton 1 , Kim Butts Pauly 1
1 Radiology, Stanford University, Palo Alto, CA, United States; 2 Electrical Engineering, Stanford University,
Palo Alto, CA, United States
The goal of this study was to compare MR-ARFI and T1-w FSE approaches to focal spot visualization during breast MRgFUS. An ex
vivo human breast tissue sample was imaged on a 3T MRI scanner equipped with an InSightec HIFU system. MR-ARFI displacement
were compared with the magnitude difference images obtained by subtraction of FSE images with ultrasound on and off. The results
of the study showed that both T1-w imaging and MR-ARFI allow visualization of the FUS focal spot., however, the MR-ARFI
approach deposits 10 times less ultrasound energy and gives 3 times greater SNR than an FSE-based approach.
Tuesday 13:30-15:30 Computer 64
13:30 4124. Integrated MRI and HIFU Control System: Towards Real Time Treatment of the
Liver
Andrew B. Holbrook 1,2 , Chuck L. Dumoulin 3 , Juan M. Santos 4,5 , Yoav Medan 6 , Kim Butts
Pauly 2
1 Bioengineering, Stanford University, Stanford, CA, United States; 2 Radiology, Stanford University, Stanford,
CA, United States; 3 Imaging Research Center, University of Cincinnati College of Medicine, Cincinnati, OH,
United States; 4 HeartVista, Los Altos, CA, United States; 5 Electrical Engineering, Stanford University,
Stanford, CA, United States; 6 InSightec Ltd, Tirat Carmel, Israel
We have developed an integrated MRI and high intensity focused ultrasound (HIFU) real time system. The system allows for both
flexible control and monitoring of both systems, from device localization utilizing MR tracking to treatment planning and therapy
monitoring utilizing MR thermometry pulse sequences. Additionally, the software allows for prescription of complex sonication
spots, including treatment paths and regions. The system was tested both in a phantom and in vivo to assess its effectiveness in
guiding HIFU therapy. Prescribed treatment plans were achieved in both experiments.
14:00 4125. In Vivo Characterization of Tissue Thermal Properties of the Kidney by HIFU
Local Hyperthermia Under MR-Thermometry with Modulation of the Arterial Flow
François Cornelis 1,2 , Nicolas Grenier 1,2 , Chrit Moonen 1 , Bruno Quesson 1
1 UMR 5231, Laboratory for molecular and functional imaging, CNRS/ Université Bordeaux 2, Bordeaux,
France; 2 Radiology Department, CHU de Bordeaux, Bordeaux, France
The purpose was to evaluate in vivo quantitatively the tissue thermal properties (perfusion, absorption, thermal diffusivity). A total of
42 localized HIFU heating were performed in the kidney of 6 pigs monitored by MR thermometry. Arterial flow was modulated by an