A5070460781- Advanced MRI Techniques and Applications
- Advanced Neuroimaging Techniques and Applications
- Medical Imaging Techniques and Applications
- Functional Brain Connectivity Studies
- Atomic and Subatomic Physics Research
- Advanced NMR Techniques and Applications
- Cardiac Imaging and Diagnostics
- NMR spectroscopy and applications
- MRI in cancer diagnosis
- Sparse and Compressive Sensing Techniques
- Neural dynamics and brain function
- Photoacoustic and Ultrasonic Imaging
- Advanced X-ray and CT Imaging
- Nuclear Physics and Applications
- Bone and Joint Diseases
- Electron Spin Resonance Studies
- Optical Imaging and Spectroscopy Techniques
- Lanthanide and Transition Metal Complexes
- Medical Image Segmentation Techniques
- Photoreceptor and optogenetics research
- Ultrasound Imaging and Elastography
- Wireless Body Area Networks
- Microwave Imaging and Scattering Analysis
- Hip disorders and treatments
- EEG and Brain-Computer Interfaces
Resonance Research (United States)
2016-2025
University of Minnesota
2016-2025
University of Minnesota System
2015-2024
John Wiley & Sons (United States)
2023
Masonic Cancer Center
2020
Institute of Electrical and Electronics Engineers
2020
Signal Processing (United States)
2020
Twin Cities Orthopedics
2019
Mayo Clinic
2019
University of California, Berkeley
2014
Abstract Parallel imaging in the form of multiband radiofrequency excitation, together with reduced k ‐space coverage phase‐encode direction, was applied to human gradient echo functional MRI at 7 T for increased volumetric and concurrent high spatial temporal resolution. Echo planar simultaneous acquisition four coronal slices separated by 44mm 4‐fold phase‐encoding undersampling, resulting 16‐fold acceleration up maximal aliasing, investigated. Task/stimulus‐induced signal changes behavior...
Echo planar imaging (EPI) is an MRI technique of particular value to neuroscience, with its use for virtually all functional (fMRI) and diffusion fiber connections in the human brain. EPI generates a single 2D image fraction second; however, it requires 2-3 seconds acquire multi-slice whole brain coverage fMRI even longer imaging. Here we report on large reduction scan time at 3 7 Tesla, without significantly sacrificing spatial resolution, while gaining sensitivity. The multiplexed-EPI...
Resting-state functional magnetic resonance imaging has become a powerful tool for the study of networks in brain. Even “at rest,” brain's different spontaneously fluctuate their activity level; each network's spatial extent can therefore be mapped by finding temporal correlations between its subregions. Current correlation-based approaches measure average connectivity regions, but this is less meaningful regions that are part multiple networks; one ideally wants network model explicitly...
RF behavior in the human head becomes complex at ultrahigh magnetic fields. A bright center and a weak periphery are observed images obtained with volume coils, while surface coils provide strong signal periphery. Intensity patterns reported often loosely referred to as "dielectric resonances," modeling studies ascribe them superposition of traveling waves greatly dampened lossy brain tissues, raising questions regarding usage this term. Here we address question experimentally, taking full...
Abstract Transceive array coils, capable of RF transmission and independent signal reception, were developed for parallel, 1 H imaging applications in the human head at 7 T (300 MHz). The coils combine advantages high‐frequency properties lines with classic MR coil design. Because short wavelength frequency 300 MHz, these straightforward to build decouple. sensitivity profiles individual highly asymmetric, as expected this high frequency; however, summed images from all relatively uniform...
To develop an improved k-space reconstruction method using scan-specific deep learning that is trained on autocalibration signal (ACS) data.Robust artificial-neural-networks for interpolation (RAKI) trains convolutional neural networks ACS data. This enables nonlinear estimation of missing lines from acquired data with noise resilience, as opposed to conventional linear interpolation-based methods, such GRAPPA, which are based kernels.The training algorithm implemented a mean square error...
Following the success of deep learning in a wide range applications, neural network-based machine techniques have received interest as means accelerating magnetic resonance imaging (MRI). A number ideas inspired by from computer vision and image processing been successfully applied to non-linear reconstruction spirit compressed sensing for both low dose computed tomography accelerated MRI. The additional integration multi-coil information recover missing k-space lines MRI process, is still...
Functional magnetic resonance imaging (fMRI) has become an indispensable tool for investigating the human brain. However, inherently poor signal-to-noise-ratio (SNR) of fMRI measurement represents a major barrier to expanding its spatiotemporal scale as well utility and ultimate impact. Here we introduce denoising technique that selectively suppresses thermal noise contribution experiment. Using 7-Tesla, high-resolution brain data, demonstrate improvements in key metrics functional mapping...
Purpose To examine the effects of reconstruction algorithm magnitude images from multichannel diffusion MRI on fiber orientation estimation. Theory and Methods It is well established that method used to combine signals different coil elements in can have an impact properties reconstructed image. Using a root‐sum‐of‐squares approach results signal follows effective noncentral‐χ distribution. As result, noise floor, minimum measurable absence any true signal, elevated. This particularly...
Abstract A novel geometrically adjustable transceiver array system is presented. key feature of the was introduction decoupling capacitors that allow for automatic change in capacitance dependent on neighboring resonant element distance. The 16‐element head version such an coil based transmission line technology compared to fixed geometry arrays (TLAs) various sizes at 7T. focus this comparison parallel imaging performance, RF transmit efficiency, and signal‐to‐noise ratio (SNR). Significant...
Functional magnetic resonance imaging (fMRI) studies that require high-resolution whole-brain coverage have long scan times are primarily driven by the large number of thin slices acquired. Two-dimensional multiband echo-planar (EPI) sequences accelerate data acquisition along slice direction and therefore represent an attractive approach to such improving temporal resolution without sacrificing spatial resolution. In this work, a 2D EPI sequence was optimized for 1.5 mm isotropic...