A5070579504- Advanced MRI Techniques and Applications
- MRI in cancer diagnosis
- Medical Imaging Techniques and Applications
- Hemoglobinopathies and Related Disorders
- Lanthanide and Transition Metal Complexes
- Sparse and Compressive Sensing Techniques
- Iron Metabolism and Disorders
- South Asian Studies and Conflicts
- Advanced NMR Techniques and Applications
- Ultrasound Imaging and Elastography
- Liver Disease Diagnosis and Treatment
- Synthetic Aperture Radar (SAR) Applications and Techniques
- Sociopolitical Dynamics in Nepal
- Spectroscopy Techniques in Biomedical and Chemical Research
- Advanced SAR Imaging Techniques
- Advanced Neural Network Applications
- Liver Disease and Transplantation
- Southeast Asian Sociopolitical Studies
- Advanced Neuroimaging Techniques and Applications
- Cardiac Imaging and Diagnostics
- Advanced Image Fusion Techniques
- Infrared Target Detection Methodologies
- Trace Elements in Health
- Wireless Networks and Protocols
- Electrical Fault Detection and Protection
Canon (United States)
2020-2024
The University of Melbourne
2023
Jawaharlal Nehru University
2022
University of Wisconsin–Madison
2013-2019
University of Southern California
2011-2013
Florida State University
2009
Arizona State University
2008
The Ohio State University
2007
Sawai ManSingh Medical College and Hospital
2006
Emerging magnetic resonance imaging (MRI) biomarkers of hepatic steatosis have demonstrated tremendous promise for accurate quantification triglyceride concentration. These methods quantify the proton density fat‐fraction (PDFF), which reflects concentration triglycerides in tissue. Previous vivo studies compared MRI‐PDFF with histologic grading assessment steatosis. However, correlation underlying content remained unknown. The aim this ex study was to validate accuracy as an biomarker Using...
Purpose: The purpose of this work was to develop and demonstrate feasibility initial clinical validation quantitative susceptibility mapping (QSM) in the abdomen as an imaging biomarker hepatic iron overload. Theory Methods: In general, QSM is faced with challenges background field removal dipole inversion. Respiratory motion, presence fat, severe overload further complicate abdomen. We propose a technique for that addresses these challenges. Data were acquired from 10 subjects without 33...
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...
We study circular synthetic aperture radar (CSAR) systems collecting backscatter measurements over a complete of 360 degrees. This is motivated by the GOTCHA CSAR data collection experiment conducted Air Force Research Laboratory (AFRL). Circular SAR provides wide-angle information about anisotropic reflectivity scattering centers in scene, and also three dimensional location due to non planar geometry. Three imaging results with single pass reveals that 3D resolution system poor limited...
The aim of this study was to determine what degree current compressed sensing methods are capable accelerating clinical magnetic resonance neuroimaging sequences.Two 2-dimensional sequences were chosen for because their long scan times. A pilot used establish the sampling scheme and regularization parameter needed in reconstruction. These findings a subsequent blinded which images reconstructed using evaluated by 2 board-certified neuroradiologists. Image quality at up 10 anatomical...
Objectives The aim of this study was to determine the relaxation properties ferumoxytol, an off-label alternative gadolinium-based contrast agents, under physiological conditions at 1.5 T and 3.0 T. Materials Methods Ferumoxytol diluted in gradually increasing concentrations (0.26–4.2 mM) saline, human plasma, whole blood. Magnetic resonance relaxometry performed 37°C Longitudinal transverse rate constants (R1, R2, R2*) were measured as a function ferumoxytol concentration, relaxivities (r1,...
Purpose We aimed to determine the agreement between quantitative susceptibility mapping (QSM)‐based biomagnetic liver susceptometry (BLS) and confounder‐corrected R2* with superconducting quantum interference device (SQUID)‐based in patients iron overload. Methods Data were acquired from two healthy controls 22 undergoing MRI SQUID‐BLS as part of routine monitoring for Magnetic resonance imaging was performed on a 3T system using three‐dimensional multi‐echo gradient‐echo acquisition. Both...
Purpose To characterize the confounding effect of temperature on chemical shift‐encoded (CSE) fat quantification. Methods The proton resonance frequency water, unlike triglycerides, depends temperature. This leads to a dependence spectral models (relative water) that are commonly used by CSE‐MRI methods. Simulation analysis was performed for 1.5 Tesla CSE fat–water signals at various temperatures and echo time combinations. Oil–water phantoms were constructed scanned between 0 40°C using...
The purpose of this work was to improve the robustness existing chemical shift encoded water-fat separation methods by incorporating object-based information B0 field inhomogeneity.The primary challenge in is estimation phase shifts that arise from inhomogeneity, which composed background and susceptibility-induced field. can be estimated if susceptibility distribution known or approximated. In work, approximated source images using values water, fat, air. estimate then demodulated before...
Abstract Water–fat separation techniques play an important role in a variety of clinical and research applications. In particular, multiecho methods remain topic great interest due to their ability resolve water fat images the presence B 0 ‐field inhomogeneity. However, these are inherently slow as they require multiple measurements. An accelerated technique with reduced k ‐space sampling is desirable decrease scan time. This work presents new method for water–fat from acquisitions. The...
The purpose of this work was to characterize the effects concomitant gradients (CGs) on chemical shift encoded (CSE)-based estimation B0 field map, proton density fat fraction (PDFF), and R2*.A theoretical framework used determine CG-induced phase errors CSE-MRI data.Simulations, phantom experiments, in vivo experiments were conducted at 3 Tesla assess CGs quantitative techniques. Correction attributable also investigated whether these could be removed.Phase attributed introduce PDFF, R2*....
Abstract Chemical shift encoded techniques have received considerable attention recently because they can reliably separate water and fat in the presence of off‐resonance. The insensitivity to off‐resonance requires that data be acquired at multiple echo times, which increases scan time as compared a single acquisition. increased often compromise made between spatial resolution, volume coverage, tolerance artifacts from subject motion. This work describes combined parallel imaging compressed...
Purpose To develop a T2*‐compensated parallel imaging and compressed sensing framework for water‐fat separation, to demonstrate accelerated quantitative of proton density fat fraction. Materials Methods The proposed method extends previously developed separation by additionally compensating T2* decay. A two‐stage estimation was formulated that first determines an approximation the B0 field map then jointly estimates refines R2* (=1/T2*) maps, respectively. tested using set phantoms as well...
Background The off-label use of ferumoxytol (FE), an intravenous iron preparation for deficiency anemia, as a contrast agent MRI is increasing; therefore, it critical to understand its pharmacokinetics. Purpose To evaluate the pharmacokinetics FE in abdomen and pelvis, assessed with quantitative 1.5- 3.0-T relaxometry. Materials Methods R2*, technique used estimate tissue content was performed at 1.5 3.0 T 12 healthy volunteers between April 2015 January 2016. Volunteers were randomly...
Background Whole‐organ, noninvasive techniques for the detection and quantification of nonalcoholic fatty liver disease features have clinical research applications. However, effect time day, hydration status, meals are unknown factors with potential to impact bias, precision, reproducibility, repeatability chemical shift‐encoded MRI (CSE‐MRI) quantify proton density fat fraction (PDFF). Purpose To assess diurnal variation on PDFF using CSE‐MRI, including as well day variability. Study Type...
Hot-spot heating occurs in a photovoltaic (PV) module when its operating current exceeds the short-circuit of shadowed or faulty cell cell-string. This shadowed/faulty could overheat due to reverse bias and become fire electrical hazard. Currently, there are three different test methods used industry identify address this issue. These based on UL 1703 (intrusive) standard, ASTM E2481-06 (non-intrusive) standard IEC 61215 standard. Comparing identifying best method [in terms time, cost...
Purpose Ferumoxytol (FE) has gained interest as an alternative to gadolinium‐based contrast agents (GBCAs). The purpose of this study was evaluate and optimize ferumoxytol dose T1 weighting, in comparison a conventional GBCA. Materials Methods Twelve healthy volunteers (six women / six men, mean age 44.3 years) were recruited for study. Scanning performed on clinical 3 Tesla (T) MRI system. Gadobenate dimeglumine (GD)‐enhanced MRA followed by FE‐enhanced 1 month later. Volunteers randomly...
Regional demands for statehood in India have had an aspiration towards a ‘nationalisation’ of their issues the hopes accommodation. In case Gorkhaland movement separate northern West Bengal, competition among regional forces to occupy and share ‘national political space’ from ‘margins’ has fuelled increasing employment debates regarding international treaty obligations. While there are numerous factors that causes mobilisation, demand abrogation Article VII India–Nepal Treaty Peace...
Purpose To evaluate the incidence and severity of potentially thrombus mimicking, flow-induced misallocation artifacts in a clinical setting. Two-point "Dixon" fat–water separation methods, with bipolar readout gradients, may suffer from artifacts. If these occur within blood vessels, they mimic thrombus. Materials Methods Dixon coronal axial images acquired 102 consecutive patients were retrospectively evaluated for presence arteries veins. Artifacts graded on 3-point scale (none, mild,...
Abstract Excised mice kidney, heart and skin MRI visible features were quantitated using ex vivo 21 Tesla microimager. The fast acquisition protocols of FLASH, gradient echo flow compensated (GEFC) techniques used to visualize microvasculature including cardiac arteries, veins, cordate tendons epidermis with hair follicle features.
At a time when the push towards ‘decoupling’ from China has gained significant traction, debates with regard to favourability of conditions China–Nepal engagement within BRI framework acquire significance. Despite being signed in 2017, it remains be seen whether ‘terms’ positive consequences for Nepal or not. Against this backdrop, and through discussion larger contours (under)development Nepal, Nepal–China relations perceptions India, we argue that indicates an attempt reframe Nepal’s...
A motion correction framework was developed to suppress artifacts from rigid and non-rigid using a combination of model-based ML-based approaches. The performance this compared with only approaches on motion-simulated data motion-corrupted in-vivo visual inspection image quality metrics. combined approach showed superior than applied individually.
Model-based Deep Unrolled Networks offer high quality reconstructions but the performance degrades if any mismatch occurs in acquisition settings. Different networks for different settings require extensive training data, addition to making clinical deployment difficult. We propose a single unrolled deep-learning algorithm called as Ada-MoDL, whose parameters are conditioned on information (metadata) of dataset, using Multi-Layer Perceptron (MLP) that maps metadata network parameters....