A5008040034- Advanced MRI Techniques and Applications
- Advanced Neuroimaging Techniques and Applications
- MRI in cancer diagnosis
- Functional Brain Connectivity Studies
- NMR spectroscopy and applications
- Neurological disorders and treatments
- Parkinson's Disease Mechanisms and Treatments
- Neural dynamics and brain function
- Bone and Joint Diseases
- Advanced NMR Techniques and Applications
- Neuroscience and Neuropharmacology Research
- Atomic and Subatomic Physics Research
- Diet and metabolism studies
- Advanced Chemical Sensor Technologies
- Lanthanide and Transition Metal Complexes
- Radiomics and Machine Learning in Medical Imaging
- Glioma Diagnosis and Treatment
- Photoacoustic and Ultrasonic Imaging
- Advanced Memory and Neural Computing
- Magnetic and Electromagnetic Effects
- Advanced Mathematical Modeling in Engineering
- Fetal and Pediatric Neurological Disorders
- Elasticity and Material Modeling
- Conducting polymers and applications
- Tensor decomposition and applications
Forschungszentrum Jülich
2014-2024
RWTH Aachen University
2011
Universidad Nacional de Córdoba
2009
Dublin City University
2009
Abstract Previous studies have reported substantial involvement of the noradrenergic system in Parkinson’s disease. Neuromelanin-sensitive MRI sequences and PET tracers become available to visualize cell bodies locus coeruleus density terminal transporters. Combining these methods, we investigated relationship neurodegeneration distinct compartments We examined 93 subjects (40 healthy controls 53 disease patients) with neuromelanin-sensitive turbo spin-echo calculated coeruleus-to-pons...
Recent diffusion MRI studies of stroke in humans and animals have shown that the quantitative parameters characterising degree non-Gaussianity process are much more sensitive to ischemic changes than apparent coefficient (ADC) considered so far as "gold standard". The observed exceeded ADC by a remarkable factor 2 3. These were based on novel non-Gaussian methods, such kurtosis imaging (DKI) log-normal distribution function (LNDFI). As our previous work investigating animal model, combined...
In this work, we report a case study of stroke model in animals using two methods quantification the deviations from Gaussian behaviour: diffusion kurtosis imaging (DKI) and log‐normal distribution function (LNDFI). The affected regions were predominantly grey rather than white matter. parameter maps constructed for metrics quantifying apparent diffusivity (evaluated conventional tensor imaging, DKI LNDFI) those degree (mean σ characterising width distribution). We showed that both LNDFI...
Diffusion kurtosis imaging (DKI) is a promising extension of diffusion tensor imaging, giving new insights into the white matter microstructure and providing biomarkers. Given rapidly increasing number studies, DKI has potential to establish itself as valuable tool in brain diagnostics. However, become routine procedure, still needs be improved terms robustness, reliability, reproducibility. As it requires acquisitions at higher weightings, results are more affected by noise than imaging....
Simultaneous trimodal positron emission tomography/magnetic resonance imaging/electroencephalography (PET/MRI/EEG) resting state (rs) brain data were acquired from 10 healthy male volunteers. The rs-functional MRI (fMRI) metrics, such as regional homogeneity (ReHo), degree centrality (DC) and fractional amplitude of low-frequency fluctuations (fALFFs), well 2-[18F]fluoro-2-desoxy-d-glucose (FDG)-PET standardised uptake value (SUV), calculated the measures extracted default mode network (DMN)...
Progressive cognitive decline following multimodal neurooncological treatment is a common observation in patients suffering from malignant glioma. Alterations of the default-mode network (DMN) represent possible source impaired neurocognitive functioning and were analyzed these patients. Eighty (median age, 51 years) with glioma (WHO grade IV glioblastoma, n = 57; WHO III anaplastic astrocytoma, 13; oligodendroglioma, 10) ECOG performance score 0-1 underwent resting-state functional MRI...
Simultaneous MR-PET-EEG (magnetic resonance imaging - positron emission tomography electroencephalography), a new tool for the investigation of neuronal networks in human brain, is presented here first time. It enables assessment molecular metabolic information with high spatial and temporal resolution given brain simultaneously. Here, we characterize brain's default mode network (DMN) healthy male subjects using multimodal fingerprinting by quantifying energy metabolism via 2-...
To design a general framework for the optimization of an MRI protocol based on diffusion-weighted dual-echo steady-state (DW-DESS) sequence, enabling quantitative and simultaneous mapping proton density (PD), relaxation times T1 T2 diffusion coefficient D.A parameterization DW-DESS sequence minimizing Cramér-Rao lower bound each parameter estimate was proposed tested in phantom experiment. An extension implemented brain imaging to return rotationally invariant mean diffusivity (MD).In NiCl2...
Clinical heterogeneity of patients with Parkinson disease (PD) is well recognized. PD REM sleep behavior disorder (RBD) a more malignant phenotype faster motor progression and higher nonmotor symptom burden. However, the neural mechanisms underlying this clinical divergence concerning imbalances in neurotransmitter systems remain elusive.
In glioma patients, multimodality therapy and recurrent tumor can lead to structural brain tissue damage characterized by pathologic findings in MR PET imaging. However, little is known about the impact of different types on fiber architecture affected white matter. This study included 121 pretreated patients (median age, 52 years; ECOG performance score, 0 48%, 1-2 51%) with histomolecularly (WHO grade IV glioblastoma, n=81; WHO III anaplastic astrocytoma, n=28; oligodendroglioma, n=12),...
Fast field-cycling (FFC) and rotating-frame nuclear magnetic resonance relaxometry were used to study molecular collective dynamics in unilamellar liposome systems. Relaxation data for liposomes of diameter about 100 nm composed 1,2-dimyristoyl-sn-glycero-3-posphocholine (DMPC) or 1,2-dioleoyl-sn-glycero-3-posphocholine (DOPC) obtained. The Larmor frequency dependence the spin−lattice relaxation rates was interpreted terms clearly defined mechanisms associated with underlying dynamics....
Glutamate is the major excitatory neurotransmitter in human brain and has a central role both intrinsic stimulus-induced activity. We conducted study cohort of healthy, male volunteers which glutamate levels were measured posterior cingulate cortex (PCC) using 1H magnetic resonance spectroscopy at 3T. The advantages simultaneous electroencephalography imaging (EEG-MRI) exploited subjects same session under physiological conditions. Diffusion tensor (DTI), functional MRI (fMRI) EEG order to...
This study aims to integrate an ultra-high-strength gradient coil system on a clinical 3 T magnet and demonstrate its preclinical imaging capabilities. Dedicated phantoms were used qualitatively quantitatively assess the performance of system. Advanced MR sequences, including diffusion tensor (DTI) quantitative susceptibility mapping (QSM), implemented executed ex vivo specimen as well in rats. The DTI QSM results phantom agreed with those literature. Furthermore, studies specimens have...
Due to technological developments in positron emission tomography (PET) detectors and PET-MR integration, the simultaneous measurement of PET-MR-EEG has become feasible, offering possibility exploring complementary information provided by each modality. Studies have already shown benefits using PET-MR, however, such achievements come with different technical practical challenges. In this context, we aim give an overview challenges involved integrating electroencephalography hybrid scanners...
Conventional diffusion‐weighted (DW) MRI suffers from free water contamination due to the finite voxel size. The most common case of occurs with cerebrospinal fluid (CSF) in voxels located at CSF‐tissue interface, such as ventricles human brain. Another refers intra‐tissue vasogenic oedema. In order avoid bias diffusion metrics, several multi‐compartment methods have been introduced, which explicitly model presence a compartment. However, fitting models DW represents well known ill...
Radiological differentiation of tumor progression (TPR) from treatment-related changes (TRC) in pretreated glioblastoma is crucial. This study aimed to explore the diagnostic value diffusion kurtosis MRI combined with information derived O-(2-[18F]-fluoroethyl)-l-tyrosine (18F-FET) PET for TPR TRC patients glioblastoma.Thirty-two histomolecularly defined and suspected having were included this retrospective study. Twenty-one group, 11 as assessed by neuropathology or clinicoradiological...
The propagation of water molecules in the brain and corresponding NMR response are affected by many factors such as compartmentalization, restrictions anisotropy imposed cellular microstructure. Interfacial interactions with cell membranes exchange additionally come into play. Due to complexity underlying factors, a differentiation between various contributions average signal vivo studies represents difficult task. In this work we perform random‐walk Monte Carlo simulations well‐defined...
Artificial, anisotropic fibre phantoms are nowadays increasingly used in the field of diffusion-weighted MRI. Such represent useful tools for, among others, calibration pulse sequences and validation diffusion models since they can mimic well-known structural features brain tissue on one hand, but exhibit a reduced complexity, other. Among all materials, polyethylene fibres have been widely due to their excellent properties regarding restriction water surface relaxation properties. Yet...