One of the greatest challenges of modern biomedical science is the mapping of the human brain to understand underlying functionality and behavior. The NIH-funded Human Connectome Project (HCP) is a large-scale multi- institutional effort that constructs a vast in-vivo database of neural connectivity pathways, acquired using diffusion and functional magnetic resonance imaging (MRI). Ultra High-Field (UHF) MRI (using magnetic field strengths of 7T and above) as part of the current and future HCP mandate provides promise of a crucial improvement over 3T HCP in spatial resolution and sensitivity for deciphering subtle features that are <1mm in size and could thus allow mapping of intricate detail such as intra-cortical or small subcortical network hubs. There are substantial hurdles to surmount, however, before the promised increases in performance for UHF MRI and thus their potential for the HCP are fully realized. This proposal focuses on two key limitations of UHF MRI that are pivotal for the success of the UHF HCP mandate: 1) the non-uniform main magnetic field B0 resulting in image artefacts/distortion, as well as 2) the problem of non-uniform power deposition in the body leading to tissue heating, which is a safety concern that has not been completely solved to date. My long-term goal is to develop hardware technology for clinical applicability of UHF MRI as an independently funded faculty member. My approach and primary goal in this five-year project is to develop a single-device compact low-cost helmet-style RF-coil array that in addition to its parallel imaging RF receive function serves the 1) main magnetic field homogenization (?shimming?) and 2) appropriate safety monitoring functions in the same apparatus, thus facilitating the generation of human connectome maps with sub-mm resolution by overcoming two critical barriers that currently limit the full potential of UHF MRI. My preliminary data demonstrates the successful proof-of-concept implementation of these two key innovations: a) I was awarded for the design of single-element RF-shim coils at 7T that combine RF receive and B0 shimming function; and b) I have pioneered a groundbreaking invention for the mapping of power deposition patterns with thermoacoustic signals. The proposed research will will not only benefit the HCP but also significantly impact the long-term clinical potential of UHF MRI by a) the improved safety-monitoring needed for FDA approval of UHF MRI; b) the improved main magnetic field homogeneity for elimination of image distortion and artefact; and c) the integration of a-b within a single compact low-cost device ? thus providing sub-mm image resolution for detection of subtle brain features at clinically accepted safety and distortion levels. Ultimately, clinical diagnostics will benefit from the proposed project with improved sensitivity and specificity for diagnosis, treatment planning, and monitoring of neurological disorders, such as Alzheimers, Parkinson?s disease, and traumatic brain injury, among others. The scope of this new technology is also broadened by its imminent applicability to 3T MRI and its sharing through the co-founded Open Source Imaging platform offering (a) networking and accessibility and (b) reduced overall cost.

Public Health Relevance

The NIH-funded Human Connectome Project (HCP) is a large-scale multi-institutional effort that constructs a vast in-vivo database of neural connectivity pathways, in an effort to understand underlying brain functionality and behavior. Ultra High-Field (UHF) MRI as part of the current and future HCP mandate provides promise of a crucial improvement in spatial resolution and sensitivity for deciphering subtle features that are <1mm in size. My approach to this project is to develop a single-device compact low-cost helmet-style RF-coil array that in addition to its parallel imaging RF receive function serves the 1) main magnetic field homogenization (?shimming?) and 2) appropriate safety monitoring functions in the same apparatus, thus facilitating the generation of human connectome maps with sub-mm resolution by overcoming two critical barriers currently limiting the full potential of UHF MRI. The proposed research will will not only benefit the HCP but also significantly impact the long-term clinical potential of UHF MRI by a) the improved safety monitoring needed for FDA approval of UHF MRI; b) the improved main magnetic field homogeneity for elimination of image distortion and artefact; and c) the integration of a-b within a single compact low-cost device ? thus providing sub-mm image resolution for detection of subtle brain features at clinically accepted safety and distortion levels. The scope of this new technology is also broadened by its imminent applicability to 3T MRI and its sharing through the co-founded Open Source Imaging platform offering (a) networking and accessibility and (b) reduced overall cost.

Agency
National Institute of Health (NIH)
Institute
National Institute of Biomedical Imaging and Bioengineering (NIBIB)
Type
Career Transition Award (K99)
Project #
5K99EB024341-02
Application #
9502282
Study Section
Special Emphasis Panel (ZEB1)
Program Officer
Wang, Shumin
Project Start
2017-07-01
Project End
2019-06-30
Budget Start
2018-07-01
Budget End
2019-06-30
Support Year
2
Fiscal Year
2018
Total Cost
Indirect Cost
Name
Stanford University
Department
Radiation-Diagnostic/Oncology
Type
Schools of Medicine
DUNS #
009214214
City
Stanford
State
CA
Country
United States
Zip Code
94304
Winkler, Simone A; Schmitt, Franz; Landes, Hermann et al. (2018) Gradient and shim technologies for ultra high field MRI. Neuroimage 168:59-70
Winkler, Simone A; Picot, Paul A; Thornton, Michael M et al. (2017) Direct SAR mapping by thermoacoustic imaging: A feasibility study. Magn Reson Med 78:1599-1606
Winkler, Simone A; Alejski, Andrew; Wade, Trevor et al. (2017) On the accurate analysis of vibroacoustics in head insert gradient coils. Magn Reson Med 78:1635-1645