A5025672631- Advanced MRI Techniques and Applications
- Functional Brain Connectivity Studies
- Advanced NMR Techniques and Applications
- Advanced Neuroimaging Techniques and Applications
- Metabolomics and Mass Spectrometry Studies
- Lanthanide and Transition Metal Complexes
- Atomic and Subatomic Physics Research
- Medical Imaging Techniques and Applications
- NMR spectroscopy and applications
- Neuroscience and Neuropharmacology Research
- Electron Spin Resonance Studies
- MRI in cancer diagnosis
- Liver Disease and Transplantation
- Autism Spectrum Disorder Research
- Neuroscience and Neural Engineering
- Nuclear Physics and Applications
- Genetics and Neurodevelopmental Disorders
- Alzheimer's disease research and treatments
- Neural dynamics and brain function
- Transcranial Magnetic Stimulation Studies
- Cardiac Imaging and Diagnostics
- Epilepsy research and treatment
- Liver Disease Diagnosis and Treatment
- Radiomics and Machine Learning in Medical Imaging
- Diet and metabolism studies
Johns Hopkins University
2016-2025
Kennedy Krieger Institute
2016-2025
Johns Hopkins Medicine
2019-2024
University of Baltimore
2021-2024
Resonance Research (United States)
2018
Mayo Clinic
2018
McMaster University
2017
Heinrich Heine University Düsseldorf
2014-2016
Short-TE proton MRS is used to study metabolism in the human brain. Common analysis methods model data as a linear combination of metabolite basis spectra. This large-scale multi-site compares levels four major complexes short-TE spectra estimated by three linear-combination modeling (LCM) algorithms. 277 medial parietal lobe PRESS (TE = 35 ms) from recent 3 T were preprocessed with Osprey software. The resulting modeled Osprey, Tarquin and LCModel, using same vendor-specific sets (GE,...
Purpose The purpose of this study is to present a cloud‐based spectral simulation tool “MRSCloud,” which allows MRS users simulate vendor‐specific and sequence‐specific basis set online in convenient time‐efficient manner. This can sets for GE, Philips, Siemens MR scanners, including conventional acquisitions editing schemes with PRESS semi‐LASER localization at 3 T. Methods MRSCloud was built on the functionality FID‐A software package. We added three extensions accelerate computation (ie,...
The interest in applying and modeling dynamic MRS has recently grown. Two-dimensional yields advantages for the precision of metabolite estimation interrelated data. However, it is unknown whether including all transients simultaneously a 2D model without averaging (presuming stable signal) performs similarly to one-dimensional (1D) averaged spectrum. Therefore, we systematically investigated accuracy, precision, uncertainty both described approaches.
Purpose To investigate the effects of B0 field offsets and drift on macromolecule (MM)-suppressed GABA-editing experiments, to implement test a prospective correction scheme. "Symmetric" editing schemes are proposed suppress unwanted coedited MM signals in GABA editing. Materials Methods Full density-matrix simulations both conventional (nonsymmetric) symmetric MM-suppressed were performed for spin system evaluate their offset-dependence. Phantom vivo (15 subjects at 3T) GABA-edited...
Neuronal oscillatory activity in the beta band (15-30 Hz) is a prominent signal within human sensorimotor cortex. Computational modeling and pharmacological modulation studies suggest an influence of GABAergic interneurons on generation oscillations. Accordingly, humans have demonstrated correlation between GABA concentrations power It remains unclear, however, if also peak frequencies whether this present cortex at rest without modulation. In study, we investigated relation endogenous...
Multiple data formats in the MRS community currently hinder sharing and integration. NIfTI-MRS is proposed as a standard spectroscopy format, implemented an extension to Neuroimaging informatics technology initiative (NIfTI) format. This standardized format can facilitate algorithm development well ease integration of analysis alongside other imaging modalities.
Edited MRS sequences are widely used for studying γ‐aminobutyric acid (GABA) in the human brain. Several algorithms available modelling these data, deriving metabolite concentration estimates through peak fitting or a linear combination of basis spectra. The present study compares seven such algorithms, using data obtained large multisite study. GABA‐edited (GABA+, TE = 68 ms MEGA‐PRESS) from 222 subjects at 20 sites were processed via standardised pipeline, before with FSL‐MRS, Gannet,...
Abstract Brain cell structure and function reflect neurodevelopment, plasticity, aging; changes can help flag pathological processes such as neurodegeneration neuroinflammation. Accurate quantitative methods to noninvasively disentangle cellular structural features are needed a substantial focus of brain research. Diffusion‐weighted MRS (dMRS) gives access diffusion properties endogenous intracellular metabolites that preferentially located inside specific populations. Despite its great...
Individuals on the autism spectrum are often reported as being hyper- and/or hyporeactive to sensory input. These symptoms were one of key observations that led development altered excitation-inhibition (E-I) model autism, which posits an increase ratio excitatory inhibitory signaling may explain certain phenotypical expressions disorders (ASD). While there has been strong support for E-I much evidence come from animal models. With regard in-vivo human studies, balance in ASD studies...
J‐difference‐edited spectroscopy is a valuable approach for the in vivo detection of γ‐aminobutyric‐acid (GABA) with magnetic resonance (MRS). A recent expert consensus article recommends linear combination modeling (LCM) edited MRS but does not give specific details regarding implementation. This study explores different strategies to adapt LCM GABA‐edited MRS. Sixty‐one medial parietal lobe MEGA‐PRESS spectra from 3‐T multisite were modeled using 102 combining six approaches account...
Abstract Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by social communication challenges and repetitive behaviors. Altered neurometabolite levels, including glutathione (GSH) gamma‐aminobutyric acid (GABA), have been proposed as potential contributors to the biology underlying ASD. This study investigated whether cerebral GSH or GABA levels differ between cohort of children aged 8–12 years with ASD ( n = 52) typically developing (TDC, 49). A comprehensive...
Background The hardware and software differences between MR vendors individual sites influence the quantification of spectroscopy data. An analysis a large data set may help to better understand sources total variance in quantified metabolite levels. Purpose To compare multisite quantitative brain acquired healthy participants at 26 by using vendor-supplied single-voxel point-resolved (PRESS) sequence. Materials Methods protocol acquire short-echo-time PRESS from midparietal region was...
Abstract Purpose To acquire the mobile macromolecule (MM) spectrum from healthy participants, and to investigate changes in signals with age sex. Methods 102 volunteers (49 M/53 F) between 20 69 years were recruited for vivo data acquisition centrum semiovale (CSO) posterior cingulate cortex (PCC). Spectral acquired at 3T using PRESS localization a voxel size of 30 × 26 mm 3 , pre‐inversion (TR/TI 2000/600 ms) CHESS water suppression. Metabolite‐nulled spectra modeled eliminate residual...