A5046300894- Advanced MRI Techniques and Applications
- Medical Imaging Techniques and Applications
- MRI in cancer diagnosis
- Advanced Neuroimaging Techniques and Applications
- Cardiovascular Disease and Adiposity
- Adipose Tissue and Metabolism
- Radiomics and Machine Learning in Medical Imaging
- Body Composition Measurement Techniques
- Atomic and Subatomic Physics Research
- Advanced X-ray Imaging Techniques
- Cardiac Imaging and Diagnostics
- Medical Image Segmentation Techniques
- Muscle metabolism and nutrition
- Thermoregulation and physiological responses
- Traumatic Brain Injury and Neurovascular Disturbances
- French Literature and Criticism
- Lanthanide and Transition Metal Complexes
- Sparse and Compressive Sensing Techniques
- Electron Spin Resonance Studies
- Photography and Visual Culture
- Bone and Joint Diseases
- Ultrasound Imaging and Elastography
- Exercise and Physiological Responses
- Multiple Sclerosis Research Studies
- Acute Ischemic Stroke Management
Vanderbilt University Medical Center
2008-2022
Welch Foundation
2020-2021
Vanderbilt University
2010-2019
LIG Science (United States)
2018
Philips (United States)
2008-2010
Philips (Finland)
2009
WinnMed
2001-2005
Mayo Clinic in Florida
2001-2005
Mayo Clinic
1998-2004
Mayo Clinic in Arizona
1999
Abstract Radiological examination of the brain is a critical determinant stroke care pathways. Accessible neuroimaging essential to detect presence intracerebral hemorrhage (ICH). Conventional magnetic resonance imaging (MRI) operates at high field strength (1.5–3 T), which requires an access-controlled environment, rendering MRI often inaccessible. We demonstrate use low-field (0.064 T) for ICH evaluation. Patients were imaged using conventional (non-contrast computerized tomography (CT) or...
Abstract We developed a 3D spherical navigator (SNAV) echo technique that can measure rigid body motion in all six degrees of freedom simultaneously by sampling shell k ‐space. rotations an imaged object simply rotate the data on this and be detected registration ‐space magnitude values. translations add phase shifts to with weighted least‐squares fit differences at corresponding points. MRI pulse sequences were study strategies such shell. Data collected computer‐controlled phantom known...
To evaluate the accuracy and reproducibility of quantitative chemical shift-encoded (CSE) MRI to quantify proton-density fat-fraction (PDFF) in a fat-water phantom across sites, vendors, field strengths, protocols.Six sites (Philips, Siemens, GE Healthcare) participated this study. A containing multiple vials with various oil/water suspensions (PDFF:0%-100%) was built, shipped each site, scanned at 1.5T 3T using two CSE protocols per strength. Confounder-corrected PDFF maps were...
To describe an initial experience imaging the human hippocampus in vivo using a 7T magnetic resonance (MR) scanner and protocol developed for very high field neuroimaging.Six normal subjects were scanned on whole body MR equipped with 16-channel head coil. Sequences included full of view T1-weighted 3D turbo echo (T1W TFE: time acquisition (TA)=08:58), T2*-weighted 2D fast (T2*W FFE: TA=05:20), susceptibility-weighted (SWI: TA=04:20). SWI data postprocessed minimum intensity projection...
Abstract Chemical exchange saturation transfer (CEST) MRI is a molecular imaging method that has previously been successful at reporting variations in tissue protein and glycogen contents pH. We have implemented amide proton (APT), specific form of chemical imaging, high field (7T) used it to study healthy human subjects patients with multiple sclerosis. The effects static inhomogeneities were mitigated using water shift referencing center each z‐spectrum on voxel‐by‐voxel basis. Contrary...
To determine the minimum water percentage in a muscle region of interest that would allow diffusion tensor (DT-) MRI data to reflect properties pure accurately.Proton density-weighted images with and without fat saturation were obtained at mid-thigh four subjects. Co-registered DT-MR used calculate tensor's eigenvalues fractional anisotropy.The transitioned monotonically as function signal from values near those expected for muscle. Also, anisotropy 0.50 (fat) 0.20 (muscle). For percentages...
Muscle diseases commonly have clinical presentations of inflammation, fat infiltration, fibrosis, and atrophy. However, the results existing laboratory tests are not well correlated. Advanced quantitative MRI techniques may allow assessment myo-pathological changes in a sensitive objective manner. To progress towards this goal, an array protocols was implemented for human thigh muscles; their reproducibility assessed; statistical relationships among parameters were determined. These methods...
Abstract Quantitative magnetization transfer imaging yields indices describing the interactions between free water protons and immobile, macromolecular protons—including to pool size ratio (PSR) rate of pools k mf . This study describes first implementation selective inversion recovery quantitative method on a clinical 3.0‐T scanner in human brain vivo. Selective data were acquired at 16 different times nine healthy subjects two patients with relapsing remitting multiple sclerosis. Data...
Activated brown adipose tissue (BAT) plays an important role in thermogenesis and whole body metabolism mammals. Positron emission tomography (PET)-computed (CT) imaging has identified depots of BAT adult humans, igniting scientific interest. The purpose this study is to characterize both active inactive supraclavicular adults compare the values those subcutaneous white (WAT). We obtained [(18)F]fluorodeoxyglucose ([(18)F]FDG) PET-CT magnetic resonance (MRI) scans 25 healthy adults. Unlike...
Abstract Neuroimaging is crucial for assessing mass effect in brain-injured patients. Transport to an imaging suite, however, challenging critically ill We evaluated the use of a low magnetic field, portable MRI (pMRI) midline shift (MLS). In this observational study, 0.064 T pMRI exams were performed on stroke patients admitted neuroscience intensive care unit at Yale New Haven Hospital. Dichotomous (present or absent) and continuous MLS measurements obtained locally available accessible...
Quantitative analysis of dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) data requires the accurate determination arterial input function (AIF). A novel method for obtaining AIF is presented here and pharmacokinetic parameters derived from individual population-based AIFs are then compared. Philips 3.0 T Achieva MR scanner was used to obtain 20 DCE-MRI sets ten breast cancer patients prior after one cycle chemotherapy. Using a semi-automated estimate axillary artery, we each...
Compressive sensing (CS) has been shown to enable dramatic acceleration of MRI acquisition in some applications. Being an iterative reconstruction technique, CS reconstructions can be more time-consuming than traditional inverse Fourier reconstruction. We have accelerated our by factors up 27 using a split Bregman solver combined with graphics processing unit (GPU) computing platform. The increases speed we find are similar those measure for matrix multiplication on this platform, suggesting...
T2*-weighted multi-echo gradient-echo magnetic resonance imaging and its reciprocal R2* are used in brain due to their sensitivity iron content. In patients with multiple sclerosis who display pathological alterations myelin contents, the use of may offer a unique way untangle mechanisms disease. Coronal slices from 8 brains deceased were imaged using whole-body 7.0 Tesla MRI scanner. The scanning protocol included three-dimensional (3D) T2*-w 2D T2-w turbo spin echo (TSE) sequences....
Dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) involves the acquisition of images before, during and after injection a agent. In order to perform quantitative modeling on resulting signal intensity time course, data must be acquired rapidly, which compromises spatial resolution, noise and/or field view. One approach that may allow for gains in temporal or resolution an individual image is use compressed sensing (CS) MRI. this study, we demonstrate accuracy extracted...
Abstract Diffusion‐weighted magnetic resonance imaging data obtained early in the course of therapy can be used to estimate tumor proliferation rates, and estimated rates predict cellularity at conclusion therapy. Six patients underwent diffusion‐weighted immediately before, after one cycle, all cycles neoadjuvant chemotherapy. Apparent diffusion coefficient values were calculated for each voxel a whole region interest. Proliferation using apparent from first two time points then with...
Obesity is a threat to public health worldwide primarily due the comorbidities related visceral adiposity, inflammation, and insulin resistance that increase risk for type 2 diabetes cardiovascular disease. The translational research portfolio originally described these factors was significantly enhanced by imaging techniques, such as dual-energy X-ray absorptiometry (DEXA), computed tomography (CT), magnetic resonance (MRI). In this article, we briefly review important contributions of...
Abstract By fitting dynamic contrast‐enhanced MRI data to an appropriate pharmacokinetic model, quantitative physiological parameters can be estimated. In this study, we compare four different models by applying statistical measures assess their ability describe obtained in 28 human breast cancer patient sets: the chi‐square test (χ 2 ), Durbin–Watson statistic, Akaike information criterion, and Bayesian criterion. The include fast exchange limit model with (FXL_ v p ) without (FXL) a plasma...
Improved understanding of how depot-specific adipose tissue mass predisposes to obesity-related comorbidities could yield new insights into the pathogenesis and treatment obesity as well metabolic benefits weight loss. We hypothesized that three-dimensional (3D) contiguous "fat-water" MR imaging (FWMRI) covering majority a whole-body field view (FOV) acquired at 3 Tesla (3T) coupled with automated segmentation quantification amount, type, distribution lean soft would show great promise in...
Purpose Head motion continues to be a major source of artifacts and data quality degradation in MRI. The goal this work was develop demonstrate novel technique for prospective, 6 degrees freedom (6DOF) rigid body estimation real-time correction using inductively coupled wireless nuclear magnetic resonance (NMR) probe markers. Methods Three probes that are with the scanner's RF setup serve as fiducials on subject's head. A 12-ms linear navigator module is interleaved imaging sequence head...