A5049356393- Advanced MRI Techniques and Applications
- Lanthanide and Transition Metal Complexes
- Electron Spin Resonance Studies
- MRI in cancer diagnosis
- Medical Imaging Techniques and Applications
- Advanced Neuroimaging Techniques and Applications
- Radiomics and Machine Learning in Medical Imaging
- Atomic and Subatomic Physics Research
- Traumatic Brain Injury and Neurovascular Disturbances
- Glioma Diagnosis and Treatment
- Magnetism in coordination complexes
- Advanced NMR Techniques and Applications
- Brain Tumor Detection and Classification
- Sparse and Compressive Sensing Techniques
- NMR spectroscopy and applications
- Cancer, Hypoxia, and Metabolism
- Cardiac Imaging and Diagnostics
- CAR-T cell therapy research
- Medical Imaging and Analysis
- Bone and Joint Diseases
- Advanced Neural Network Applications
- Acute Ischemic Stroke Management
- AI in cancer detection
- Medical Image Segmentation Techniques
- Dementia and Cognitive Impairment Research
Johns Hopkins University
2016-2025
Johns Hopkins Medicine
2014-2024
First Affiliated Hospital of GuangXi Medical University
2024
Guangxi Medical University
2024
Lanzhou University
2020-2024
Nanjing University
2024
Kennedy Krieger Institute
2010-2019
Zhejiang Provincial Natural Science Foundation
2017
Foundation for the National Institutes of Health
2017
Southern Medical University
2014-2017
Abstract Chemical exchange saturation transfer (CEST) is a contrast mechanism that exploits exchange‐based magnetization (MT) between solute and water protons. CEST effects compete with direct conventional MT processes, generally can only be quantified through an asymmetry analysis of the spectrum ( Z ‐spectrum) respect to frequency, process exquisitely sensitive magnetic field inhomogeneities. Here it shown imaging allows measurement absolute frequency in each voxel, allowing proper...
Abstract In this work we demonstrate that specific MR image contrast can be produced in the water signal reflects endogenous cellular protein and peptide content intracranial rat 9L gliosarcomas. Although concentration of these mobile proteins peptides is only millimolar range, a detection sensitivity several percent on (molar concentration) was achieved. This accomplished with enhancement by selective radiofrequency (RF) labeling amide protons, utilizing effective transfer label to via...
The classic definition of the ischemic penumbra is a hypoperfused region in which metabolism impaired, but still sufficient to maintain cellular polarization. Perfusion- and diffusion-weighted MRI (PWI, DWI) can identify regions reduced perfusion depolarization, respectively, it often remains unclear whether PWI—DWI mismatch corresponds benign oligemia or true penumbra. We hypothesized that pH-weighted (pHWI) subdivide into these regions. Twenty-one rats underwent permanent middle cerebral...
Abstract Amide proton transfer (APT) imaging is a technique in which the nuclear magnetization of water‐exchangeable amide protons endogenous mobile proteins and peptides tissue saturated, resulting signal intensity decrease free water. In this work, first human APT data were acquired from 10 patients with brain tumors on 3T whole‐body clinical scanner compared T 1 ‐ ( w) 2 ‐weighted w), fluid‐attenuated inversion recovery (FLAIR), diffusion images (fractional anisotropy (FA) apparent...
Abstract The ability to measure proton exchange rates in tissue using MRI would be very useful for quantitative assessment of magnetization transfer properties, both conventional MT imaging and the more recent chemical saturation (CEST) approach. CEST is a new MR contrast mechanism that depends on several factors, including rate labile protons agent pH‐dependent manner. Two methods monitor local based are introduced. two MRI‐compatible approaches quantifying time (QUEST) dependence power...
Abstract Amide proton transfer (APT) imaging is a type of chemical exchange–dependent saturation (CEST) magnetic resonance (MRI) in which amide protons endogenous mobile proteins and peptides tissue are detected. Initial studies have shown promising results for distinguishing tumor from surrounding brain patients, but these data were hampered by field inhomogeneity low signal‐to‐noise ratio (SNR). Here practical six‐offset APT acquisition scheme presented that, together with separately...
To quantitatively compare the potential of various diffusion parameters obtained from monoexponential, biexponential, and stretched exponential diffusion-weighted imaging models kurtosis in grading gliomas.This study was approved by local ethics committee, written informed consent all subjects. Both were performed 69 patients with pathologically proven gliomas using a 3-T magnetic resonance (MR) unit. An isotropic apparent coefficient (ADC), true ADC, pseudo-ADC, perfusion fraction...
Fast and accurate reconstruction of magnetic resonance (MR) images from under-sampled data is important in many clinical applications. In recent years, deep learning-based methods have been shown to produce superior performance on MR image reconstruction. However, these require large amounts which difficult collect share due the high cost acquisition medical privacy regulations. order overcome this challenge, we propose a federated learning (FL) based solution take advantage available at...
The accelerating magnetic resonance imaging (MRI) reconstruction process is a challenging ill-posed inverse problem due to the excessive under-sampling operation in <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${k}$ </tex-math></inline-formula> -space. In this paper, we propose recurrent Transformer model, namely ReconFormer, for MRI reconstruction, which can iteratively reconstruct high-fidelity images...
The proton exchange processes between water and solutes containing exchangeable protons have recently become of interest for monitoring pH effects, detecting cellular mobile proteins peptides, enhancing the detection sensitivity various low-concentration endogenous exogenous species. In this work, analytic expressions (WEX) filter spectroscopy, chemical exchange-dependent saturation transfer (CEST), amide (APT) experiments are derived by use Bloch equations with terms. effects initial states...
The mechanism of magnetization transfer (MT) between water and components the proton spectrum was studied ex vivo in a perfused cell system rat brain (n = 5). Water selectively labeled spectral buildup consequential to longitudinal followed as function time. At short mixing time (T(m)), nitrogen-bound solvent-exchangeable protons were observed, predominantly assigned amide groups proteins peptides. longer T(m), intramolecular nuclear Overhauser enhancement (NOE) observed aliphatic region,...
Abstract Magnetization transfer (MT) imaging provides a unique method of tissue characterization by capitalizing on the interaction between solid‐like components and bulk water. We used continuous‐wave (CW) MT pulse sequence with low irradiation power to study healthy human brains in vivo at 3 T quantified asymmetry effects respect water proton frequency. This was found be difference approximately few percent from signal intensity, depending both RF frequency offset. The experimental results...
Purpose To investigate the feasibility of a three‐dimensional amide‐proton‐transfer (APT) imaging sequence with gradient‐ and spin‐echo readouts at 3 Tesla in patients high‐ or low‐grade gliomas. Materials Methods Fourteen newly diagnosed gliomas were recruited. After B 0 inhomogeneity correction on voxel‐by‐voxel basis, APT‐weighted images reconstructed using magnetization‐transfer‐ratio asymmetry offsets ±3.5 ppm respect to water resonance. Analysis variance post hoc tests used for...
Abstract Chemical exchange saturation transfer (CEST) is a technique to indirectly detect pools of exchangeable protons through the water signal. To increase its applicability human studies, it needed develop sensitive pulse sequences for rapidly acquiring whole‐organ images while adhering stringent amplifier duty cycle limitations and specific absorption rate restrictions. In addition, interfering effects direct conventional magnetization contrast complicate CEST quantification need be...
Abstract Purpose: To evaluate the capability of amide proton transfer (APT) MR imaging for detection prostate cancer that typically shows a higher tumor cell proliferation rate and cellular density leading to an MRI‐detectable overall elevated mobile protein level in grade tumors. Materials Methods: Twelve patients with biopsy‐proven were imaged on 3 Tesla system before prostatectomy. APT‐MR images acquired by means single‐slice single‐shot turbo spin echo sequence saturation prepulse...
Purpose To assess amide proton transfer‐weighted (APTW) imaging features in patients with malignant gliomas after chemoradiation and the diagnostic performance of APT for distinguishing true progression from pseudoprogression. Materials Methods After approval by Institutional Review Board, 32 clinically suspected tumor first 3 months were enrolled scanned at 3T. Longitudinal routine magnetic resonance (MRI) changes medical records assessed to confirm versus True was defined as lesions...
Chemical exchange saturation transfer magnetic resonance imaging can detect low-concentration compounds with exchangeable protons through to water. This technique is generally slow, as it requires acquisition of images at multiple frequencies. In addition, multislice complicated by effects differing from slice because relaxation losses. this study, a fast three-dimensional chemical sequence presented that allows whole-brain coverage for frequency-dependent spectrum (z-spectrum, 26...
Amide proton transfer (APT) imaging is capable of detecting mobile cellular proteins and peptides in tumor monitoring pH effects stroke, through the saturation between irradiated amide protons water protons. In this work, four healthy subjects, eight brain patients (four with high-grade glioma, one lung cancer metastasis, three meningioma), stroke (average 4.3 ± 2.5 days after onset stroke) were scanned at 3 T, using different radiofrequency powers. The APT effect was quantified...