The goal of this project is to improve magnetic resonance temperature imaging (MRTI) techniques to be used in high intensity focused ultrasound (HIFU) thermal treatments by significantly expanding their current spatial and temporal resolution and field of view (FOV) capabilities. These improvements will overcome the speed, resolution, and FOV roadblocks in transcranial MRI guided focused ultrasound therapy and thereby accelerate the acceptance of this technique into clinical practice. To realize this goal we propose to develop a completely new MRTI approach that increases speed by subsampling the measurement space (k-space) in each time frame and that uses a subject-specific biophysical model incorporating inhomogeneous tissue biothermal and acoustic properties to dynamically (in real-time) predict the missing measurements. The uniqueness of this approach is that it supplements 3D MRTI with additional subject-specific biophysical information. We refer to this method as model predictive filtering (MPF) because it is similar to other linear predictive filters, such as the Kalman filter. This new MPF technique will achieve the required accurate, precise, and rapid high-resolution measurements of temperature distributions over regions sufficiently large to effectively monitor and control treatments in real-time. The work will develop methods to improve temperature measurements in three stages: 1) First a temporally-constrained reconstruction (TCR) technique will be developed to obtain retrospective MRTI measurements with high spatial and temporal resolution over the volume of interest. 2) The TCR temperatures combined with tissue segmentation and beam modeling will be used to determine 3D subject- specific tissue acoustic and thermal properties. 3) The tissue acoustic and thermal properties will be incorporated into the MPF technique to obtain the desired temperature images over the full insonified volume in real-time. These methods will then be tested in vivo in animal models and in vitro and ex vivo in a transcranial MRgHIFU system. Transcranial brain MRgHIFU is an important application that requires the development of innovative treatment strategies and will definitely require rapid, accurate, high spatial resolution temperature measurements over the entire insonified volume. These techniques are highly novel, and upon success will facilitate experiments to accelerate the acceptance of transcranial brain MRgHIFU as well as potentially other new MRgHIFU applications.

Public Health Relevance

This project will be the first to develop and validate a method for obtaining MRI temperature measurements at very high spatial and temporal resolution covering the full image volume treated by High Intensity Focused Ultrasound and thus remove a major roadblock currently inhibiting clinical application of transcranial MRI guided focused ultrasound therapy. These techniques will improve the accuracy of thermal dose delivery measurements as well as develop methods to detect changes in tissue thermal and acoustic properties.

Agency
National Institute of Health (NIH)
Institute
National Institute of Biomedical Imaging and Bioengineering (NIBIB)
Type
Research Project (R01)
Project #
5R01EB013433-02
Application #
8305993
Study Section
Biomedical Imaging Technology Study Section (BMIT)
Program Officer
Liu, Guoying
Project Start
2011-08-01
Project End
2015-06-30
Budget Start
2012-07-01
Budget End
2013-06-30
Support Year
2
Fiscal Year
2012
Total Cost
$423,511
Indirect Cost
$134,075
Name
University of Utah
Department
Radiation-Diagnostic/Oncology
Type
Schools of Medicine
DUNS #
009095365
City
Salt Lake City
State
UT
Country
United States
Zip Code
84112
de Bever, Joshua T; Odéen, Henrik; Hofstetter, Lorne W et al. (2018) Simultaneous MR thermometry and acoustic radiation force imaging using interleaved acquisition. Magn Reson Med 79:1515-1524
Freeman, Nicholas J; Odéen, Henrik; Parker, Dennis L (2018) 3D-specific absorption rate estimation from high-intensity focused ultrasound sonications using the Green's function heat kernel. Med Phys 45:3109-3119
Svedin, Bryant T; Beck, Michael J; Hadley, J Rock et al. (2017) Focal point determination in magnetic resonance-guided focused ultrasound using tracking coils. Magn Reson Med 77:2424-2430
Svedin, Bryant T; Parker, Dennis L (2017) Technical Note: The effect of 2D excitation profile on T1 measurement accuracy using the variable flip angle method with an average flip angle assumption. Med Phys 44:5930-5937
Odéen, Henrik; Almquist, Scott; de Bever, Joshua et al. (2016) MR thermometry for focused ultrasound monitoring utilizing model predictive filtering and ultrasound beam modeling. J Ther Ultrasound 4:23
Svedin, Bryant T; Payne, Allison; Parker, Dennis L (2016) Respiration artifact correction in three-dimensional proton resonance frequency MR thermometry using phase navigators. Magn Reson Med 76:206-13
de Bever, Joshua T; Odéen, Henrik; Todd, Nick et al. (2016) Evaluation of a three-dimensional MR acoustic radiation force imaging pulse sequence using a novel unbalanced bipolar motion encoding gradient. Magn Reson Med 76:803-13
Almquist, Scott; Parker, Dennis L; Christensen, Douglas A (2016) Rapid full-wave phase aberration correction method for transcranial high-intensity focused ultrasound therapies. J Ther Ultrasound 4:30
Dillon, C R; Borasi, G; Payne, A (2016) Analytical estimation of ultrasound properties, thermal diffusivity, and perfusion using magnetic resonance-guided focused ultrasound temperature data. Phys Med Biol 61:923-36
Odéen, Henrik; Todd, Nick; Dillon, Christopher et al. (2016) Model predictive filtering MR thermometry: Effects of model inaccuracies, k-space reduction factor, and temperature increase rate. Magn Reson Med 75:207-16

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