A5004523038- Advanced MRI Techniques and Applications
- Medical Imaging Techniques and Applications
- Ultrasound and Hyperthermia Applications
- Radiomics and Machine Learning in Medical Imaging
- Orthopaedic implants and arthroplasty
- Advanced Neuroimaging Techniques and Applications
- Photoacoustic and Ultrasonic Imaging
- MRI in cancer diagnosis
- Hemophilia Treatment and Research
- Bone and Joint Diseases
- Cardiac Imaging and Diagnostics
- Cardiovascular Function and Risk Factors
- Blood Coagulation and Thrombosis Mechanisms
- Advanced Biosensing Techniques and Applications
- Child Nutrition and Water Access
- Neonatal and fetal brain pathology
- Ultrasonics and Acoustic Wave Propagation
- Functional Brain Connectivity Studies
- Advanced NMR Techniques and Applications
- Total Knee Arthroplasty Outcomes
- Advanced Radiotherapy Techniques
- Advanced X-ray and CT Imaging
- Infant Development and Preterm Care
- Advanced X-ray Imaging Techniques
- Musculoskeletal synovial abnormalities and treatments
Leiden University Medical Center
2024-2025
University of Stavanger
2024
University Medical Center Utrecht
2020-2024
Utrecht University
2020-2024
Heidelberg University
2021-2022
University Hospital Heidelberg
2021-2022
Measures of physical growth, such as weight and height have long been the predominant outcomes for monitoring child health evaluating interventional in public studies, including those that may impact neurodevelopment. While growth generally reflects overall nutritional status, it lacks sensitivity specificity to brain developing cognitive skills abilities. Psychometric tools, e.g., Bayley Scales Infant Toddler Development, afford more direct assessment development but they require language...
Abstract Purpose To evaluate accelerated T 1 ‐ and 2 ‐mapping techniques for ultra–low‐field MRI using low‐rank reconstruction methods. Methods Two low‐rank–based algorithms, image‐based locally (LLR) k‐space–based structured (SLR), were implemented to accelerate mapping on a 46 mT Halbach scanner. Data acquired with 3D turbo spin‐echo sequences variable‐density poisson‐disk random sampling patterns. For validation, phantom in vivo experiments performed six healthy volunteers compare the...
Visualization of the bone distribution is an important prerequisite for MRI-guided high-intensity focused ultrasound (MRI-HIFU) treatment planning metastases. In this context, we evaluated MRI-based synthetic CT (sCT) imaging visualization cortical bone.MR and images nine patients with pelvic femoral metastases were retrospectively analyzed in study. The metastatic lesions osteolytic, osteoblastic or mixed. sCT generated from pre-treatment MR using a UNet-like neural network. was...
T2-relaxometry could differentiate between physiological and haemorrhagic joint effusion (≥ 5% blood) in vitro. Are quantitative T2-relaxation time measurements of synovial fluid feasible reproducible vivo clinically bleed-free joints men with haemophilia?
Intra-articular blood causes irreversible joint damage, whilst clinical differentiation between haemorrhagic effusion and other effusions can be challenging. An accurate non-invasive method for the detection of bleeds is lacking. The aims this phantom study were to investigate whether magnetic resonance imaging (MRI) T1 T2 mapping allows simple determine lowest concentration that detected.Solutions synovial fluid with concentrations ranging from 0 100% scanned at 1.5, 3, 7 T. maps generated...
Background Differences in imaging parameters influence computer‐extracted parenchymal enhancement measures from breast MRI. Purpose To investigate the effect of differences dynamic contrast‐enhanced MRI acquisition parameter settings on quantitative breast, and to evaluate harmonization contrast‐enhancement values with respect flip angle repetition time. Study Type Retrospective. Phantom/Populations We modeled using simulations, a phantom, two cohorts ( N = 398 302) independent cancer...
Purpose To demonstrate that interleaved MR thermometry can monitor temperature in water and fat with adequate temporal resolution. This is relevant for high intensity focused uUltrasounds (HIFU) treatment of bone lesions, which are often found near aqueous tissues, as muscle, or embedded adipose subcutaneous marrow. Methods Proton resonance frequency shift (PRFS)‐based scans T 1 ‐based 2D variable flip angle (2D‐VFA) were acquired alternatingly over time. Temperature was monitored using PRFS...
Contrast mechanisms such as T1ρ and MT are interesting for point-of-care (POC) low field systems, to supplement/augment standard T1- T2- weighting. However they typically require high B0 homogeneity. Here, we use a homogeneity Halbach-magnet array POC perform experiments involving either direct on- or off-resonance pulses, calculate ratio in tissue-mimicking phantoms. showed different white matter (WM)/gray (GM) contrast compared T2. The measured magnetization transfer (MTR) higher values...
Motivation: Low-field MRI holds promise for efficient diagnostics. T1 mapping is valuable in neuroscience studying myelination and brain development. To reduce scan time, incoherent, variable density trajectories are often used. Goal(s): to reach high image quality accuracy fast at 64 mT. Approach: Using the 64-mT, Hyperfine Swoop scanner, we compared maps acquired with fully sampled undersampled (with without incoherence) reconstructed them locally low rank regularization different factors...
Motivation: Limited access to medical equipment makes low-field MRI an interesting option in many settings. One challenge is the prolonged scan time, especially for quantitative imaging. However, parallel imaging typically not used due very high sensitivity of a single solenoid receive coil. Goal(s): This study aims accelerate T1 mapping (used estimating brain myelination) on Halbach system. Approach: A locally low-rank reconstruction was applied diminish undersampling artifacts from...
Motivation: Low-field MRI holds the promise of expanding access to healthcare. The low signal-to-noise ratio (SNR) poses a significant challenge acquiring diagnostically useful information in reasonable scanning time. Goal(s): To overcome SNR low-field MRI, achieving fast, self-supervised denoising. Approach: A rapid 4D-denoising method utilizing Zero-Shot-Noise2Noise framework is proposed, without need for intensive network training. Results: This provides fast denoising just 10-20 seconds...
Motivation: Here, we exploited the Low SAR in low-field MRI to study magnetization transfer (MT) , and potential enhance brain tissue contrast, particular between white gray matter (challenging at low-field). Goal(s): The aimed identify suitable MT settings explore contrast in-vivo 46 mT. Approach: were optimized minimize direct saturation maximize contrast. With this setup, scanned five volunteers mT acquired additional 3T scans for two participantsResults: Optimal defined phantom...
To perform dynamic T1 mapping using a 2D variable flip angle (VFA) method, correction for the slice profile effect is needed. In this work we investigated impact of selection and excitation RF pulse on performance when applied to over range values.A proposed, based Bloch simulation steady-state signals. With correction, Monte Carlo simulations were performed assess accuracy precision VFA in presence noise, pulses with time-bandwidth products 2, 3 10 pairs [1°-90°]. evaluate its wide ,...
Purpose or Learning Objective: Patients with hemophilia have an increased risk of joint bleeding. Adequate treatment is crucial to prevent irreversible damage. However, bleeds are often difficult distinguish from arthropathic pain. T2 relaxometry magnetic resonance imaging (MRI) can differentiate between physiologic and hemorrhagic effusion (≥ 5% blood) in vitro because the iron-containing blood shortens relaxation time. This study evaluated feasibility reproducibility MRI time measurements vivo.