A5023598943- Advanced MRI Techniques and Applications
- Advanced Neuroimaging Techniques and Applications
- Medical Imaging Techniques and Applications
- Advanced NMR Techniques and Applications
- Functional Brain Connectivity Studies
- NMR spectroscopy and applications
- Atomic and Subatomic Physics Research
- Dementia and Cognitive Impairment Research
- Alzheimer's disease research and treatments
- Cardiac Imaging and Diagnostics
- Nuclear Physics and Applications
- Electron Spin Resonance Studies
- Material Dynamics and Properties
- Memory and Neural Mechanisms
- Lanthanide and Transition Metal Complexes
- EEG and Brain-Computer Interfaces
- Health, Environment, Cognitive Aging
- Cellular Mechanics and Interactions
- Ultrasonics and Acoustic Wave Propagation
- Sparse and Compressive Sensing Techniques
- Neural dynamics and brain function
- History and advancements in chemistry
- Blind Source Separation Techniques
- Non-Destructive Testing Techniques
- Collagen: Extraction and Characterization
Physikalisch-Technische Bundesanstalt
2017-2024
Shandong First Medical University
2021
Shandong University
2021
University Medical Center Utrecht
2020
ETH Zurich
2014-2017
Institute for Biomedical Engineering
2014-2017
TU Dortmund University
2009-2010
The orbitofrontal cortex (OFC) is implicated in depression. hypothesis investigated was whether the OFC sensitivity to reward and nonreward related severity of depressive symptoms. Activations monetary incentive delay task were measured IMAGEN cohort at ages 14 years (n = 1877) 19 1140) with a longitudinal design. Clinically relevant subgroups compared (high-severity group: n 116; low-severity 206) 14. medial exhibited graded activation increases reward, lateral had nonreward. In this...
Heating of gradient coils and passive shim components is a common cause instability in the B0 field, especially when intensive sequences are used. The aim study was to set benchmark for typical drift encountered during MR spectroscopy (MRS) assess need real-time field-frequency locking on MRI scanners by comparing field data from large number sites. A standardized protocol developed 80 participating sites using 99 3T 3 major vendors. Phantom water signals were acquired before after an EPI...
Frailty is a common syndrome in older individuals that associated with poor cognitive outcome. The underlying brain correlates of frailty are unclear. aim this study was to investigate the association between and MRI features cerebral small vessel disease group non-demented individuals. We included 170 participants who were classified as frail (n = 30), pre-frail 85) or non-frail 55). white matter hyperintensity volume shape features, lacunar infarcts perfusion investigated by regression...
The low-temperature dielectric relaxation of collagen and elastin was studied over a wide range hydrations h. hydration-shell response increases weakly with temperature, is thermally activated, conforms to energy barrier scaling. This demonstrates the existence decoupled, secondary akin that in binary structural glasses. Indications for fragile-to-strong transitions other changes mechanism are not found hydrated elastin. For low h, strength superlinearly h; concomitantly, water molecules...
To improve B0 shimming for applications in high- and ultrahigh-field magnetic resonance imaging spectroscopy.An existing image-based constrained algorithm was enhanced using two techniques: (1) A region of less interest introduced to control field inhomogeneities the vicinity interest; (2) multiple sets starting values were used fitting routine, avoid "getting trapped" a local minimum optimization function. The influence constraints during procedure, due hardware limitations, on shim result...
Purpose To substantially improve spatial localization in magnetic resonance spectroscopic imaging (MRSI) accelerated by parallel imaging. This is important order to make MRSI more reliable as a tool for clinical applications. Methods The sensitivity encoding acceleration technique with overdiscretization applied the reconstruction of MRSI. In addition, response function optimized minimizing its deviation from previously chosen target function. modified minimum‐norm encoding‐MRSI approach...
Abstract Introduction The goal of European Ultrahigh‐Field Imaging Network in Neurodegenerative Diseases (EUFIND) is to identify opportunities and challenges 7 Tesla (7T) MRI for clinical research applications neurodegeneration. EUFIND comprises 22 one US site, including over 50 dementia experts as well neuroscientists. Methods combined consensus workshops data sharing multisite analysis, focusing on core topics: applications/clinical research, highest resolution anatomy, functional imaging,...
Abstract Delirium is associated with long-term cognitive dysfunction and increased brain atrophy. However, it unclear whether these problems result from or predisposes to delirium. We aimed investigate preoperative postoperative changes, as well the role of delirium in changes over time. investigated effects surgery MRIs made before 3 months after major elective 299 elderly patients, an MRI a follow-up 48 non-surgical control participants. To study delirium, we compared volumes, white matter...
The hippocampus is the most prominent single region of interest (ROI) for diagnosis and prediction Alzheimer's disease (AD). However, its suitability in earliest stages cognitive decline, i.e., subjective decline (SCD), remains uncertain which warrants pursuit alternative or complementary regions. amygdala might be a promising candidate, given implication memory as well other psychiatric disorders, e.g. depression anxiety, are prevalent SCD. In this 7 tesla (T) magnetic resonance imaging...
Purpose To compare several different optimization algorithms currently used for localized in vivo B 0 shimming, and to introduce a novel, fast, robust constrained regularized algorithm ( ConsTru ) this purpose. Methods Ten (including samples from both generic dedicated least‐squares solvers, novel inversion method) were implemented compared shimming five volumes on 66 data sets 7 T 9.4 T. The best was chosen perform single‐voxel spectroscopy at the frontal cortex of brain 10 volunteers....
Purpose To calibrate a pre‐emphasis to sufficiently compensate eddy currents for application of dynamic shim updating fMRI without extension scan times. Methods Eddy current effects induced into all terms up third‐order were characterized by spatiotemporal field monitoring, using camera. Pre‐emphasis settings derived from the measurements and iteratively evaluated refined. The calibrated was applied slice‐wise in combination with excitation frequency (F0) determination B 0 optimization...
Inhomogeneities of the main magnetic field cause line broadening and location-dependent frequency shifts in brain MRSI. These are often visible despite advanced B0 shimming. The purpose this work is to propose an correction method that can easily be applied during postprocessing.A target-driven overdiscrete reconstruction previously introduced for MRSI modified by dividing it into two steps. In a first step, intermediate spectroscopic image with arbitrarily high resolution generated, on...
Abstract BACKGROUND Associations between longitudinal changes of plasma biomarkers and cerebral magnetic resonance (MR)‐derived measurements in Alzheimer's disease (AD) remain unclear. METHODS In a study population ( n = 127) healthy older adults patients within the AD continuum, we examined associations amyloid beta 42/40 ratio, tau phosphorylated at threonine 181 (p‐tau181), glial fibrillary acidic protein (GFAP), neurofilament light chain (NfL), 7T structural functional MR imaging...
Abstract Conditions such as type II diabetes are linked with elevated lipid levels in the heart, and significantly increased risk of heart failure; however, metabolic processes underlying development cardiac disease not fully understood. Here we present a non-invasive method for vivo investigation metabolism: namely, IVS-McPRESS. This technique uses metabolite-cycled, non-water suppressed 1 H magnetic resonance spectroscopy prospective retrospective motion correction. High-quality...
Background: Magnetic resonance imaging (MRI) is indispensable for diagnosing neurological conditions such as multiple sclerosis (MS).MRI also supports decisions regarding the choice of disease-modifying drugs (DMDs).Determining in vivo tissue concentrations DMDs has potential to become an essential clinical tool therapeutic drug monitoring (TDM).The aim here was examine feasibility fluorine-19 ( 19 F) MR methods detect fluorinated DMD teriflunomide (TF) during normal and pathological...
Abstract A growing body of literature suggests the important role thalamus in cognition and neurodegenerative diseases. This study aims to elucidate whether preoperative thalamic volume is associated with cognitive impairment (preCI) it predictive for postoperative dysfunction at 3 months (POCD). We enrolled 301 patients aged 65 or older without signs dementia who were undergoing elective surgery. Magnetic resonance imaging was conducted prior Freesurfer (version 5.3.) used automatically...
Fluorine (19F) magnetic resonance imaging (MRI) is severely limited by a low signal-to noise ratio (SNR), and tapping it for 19F drug detection in vivo still poses significant challenge. However, bears the potential label-free theranostic imaging. Recently, we detected fluorinated dihydroorotate dehydrogenase (DHODH) inhibitor teriflunomide (TF) noninvasively an animal model of multiple sclerosis (MS) using MR spectroscopy (MRS). In present study, probed distinct modifications to CF3 group...
Objective: We propose a method for the reconstruction of parameter-maps in Quantitative Magnetic Resonance Imaging (QMRI). Methods: Because different quantitative differ from each other terms local features, we where employed dictionary learning (DL) and sparse coding (SC) algorithms automatically estimate optimal dictionary-size sparsity level separately parameter-map. evaluated on $T_1$-mapping QMRI problem brain using BrainWeb data as well in-vivo images acquired an ultra-high field 7T...
Purpose To introduce a study design and statistical analysis framework to assess the repeatability, reproducibility, minimal detectable changes (MDCs) of metabolite concentrations determined by in vivo MRS. Methods An unbalanced nested was chosen acquire MRS data within different repeatability reproducibility scenarios. A spin‐echo, full‐intensity acquired localized (SPECIAL) sequence employed at 7 T utlizing three inversion pulses: hyperbolic secant (HS), gradient offset independent...
Introduction Single‐voxel 1 H MRS in body applications often suffers from respiratory and other motion induced phase frequency shifts, which lead to incoherent averaging hence suboptimal results. Methods Here we show the application of metabolite cycling (MC) for liver STEAM‐localized on a 7 T parallel transmit system, using eight transmit‐receive fractionated dipole antennas with 16 additional, integrated receive loops. MC‐STEAM measurements were made six healthy, lean subjects compared...
Introduction: The hippocampus is the most prominent single region of interest (ROI) for diagnosis and prediction Alzheimer’s disease (AD). However, its suitability in earliest stages cognitive decline, i.e., subjective decline (SCD), remains uncertain which warrants pursuit alternative or complementary regions. amygdala might be a promising candidate, given implication memory as well other psychiatric disorders, e.g. depression anxiety, are prevalent SCD. In this 7 tesla (T) magnetic...
To ensure reliable diagnosis and treatment consistently throughout healthcare, metrological quality assurance is essential. There are, however, many observations in the social sciences such as memory tests studied here, which have been 'claimed' to be measurements but fact not fully metrologically legitimated. We already argued favour of extending traditional underlying principles cover measurements, including development construct specification equations (CSE) considered 'recipes for...
Abstract Background The NeuroMET project aims are to develop: 1) a “NeuroMET memory metric” metrologically validated with clinical laboratory data that will be implemented into app for delivery of cognitive tests 2) 7T magnetic resonance imaging and spectroscopy protocols measurement uncertainty frameworks clinic applied larger studies; 3) reference procedures liquid chromatography based methods t‐tau; p‐tau; α‐synuclein, NF‐L underpin standardisation initiatives; 4) new quantification...