A5012295393- Advanced MRI Techniques and Applications
- Ultrasound and Hyperthermia Applications
- Photoacoustic and Ultrasonic Imaging
- Aortic aneurysm repair treatments
- Aortic Disease and Treatment Approaches
- Ultrasound Imaging and Elastography
- Uterine Myomas and Treatments
- MRI in cancer diagnosis
- Medical Image Segmentation Techniques
- Atomic and Subatomic Physics Research
- Medical Imaging Techniques and Applications
- Endometriosis Research and Treatment
- Osteoarthritis Treatment and Mechanisms
- Cardiac, Anesthesia and Surgical Outcomes
- Cardiac Imaging and Diagnostics
- Management of metastatic bone disease
- Spinal Fractures and Fixation Techniques
- Scoliosis diagnosis and treatment
- Advanced Radiotherapy Techniques
- Cerebrovascular and Carotid Artery Diseases
- Medical Imaging and Analysis
- Renal and Vascular Pathologies
- Total Knee Arthroplasty Outcomes
- Knee injuries and reconstruction techniques
- Lanthanide and Transition Metal Complexes
University Medical Center
2025
University Medical Center Utrecht
2015-2024
Heidelberg University
2010-2024
University Hospital Heidelberg
2010-2024
Utrecht University
2011-2022
Institut d'Imagerie Biomédicale
2009
University of Groningen
2008
De Nederlandsche Bank
1974
Vrije Universiteit Amsterdam
1974
We examined the unwanted radiofrequency (RF) heating of an endovascular guidewire frequently used in interventional magnetic resonance imaging (MRI). A Terumo was partly immersed oblong saline bath to simulate intervention. The temperature rise tip during FFE sequence [average specific absorption rate (SAR) = 3.9 W/kg] measured with a Luxtron fluoroscopic fiber. Starting from 26°C, reached temperatures up 74°C after 30 seconds scanning. Touching may cause sudden at point contact, which one...
To assess the safety and feasibility of MRI-guided high-intensity focused ultrasound (MR-HIFU) ablation in breast cancer patients using a dedicated platform. Patients with early-stage invasive underwent partial tumour prior to surgical resection. MR-HIFU was performed proton resonance frequency shift MR thermometry an system specifically designed for ablation. The presence extent necrosis assessed by histopathological analysis specimen. Pearson correlation coefficients were calculated...
In Brief Study Design. A newly developed CT measurement method was used to investigate axial rotation from T2 L5 in the normal, nonscoliotic spine. Objectives. To identify a preexistent rotational pattern Summary of Background Data. The data available on measurements normal spine are scant and limited only few vertebrae. Systematic analysis thoracic lumbar vertebrae spine, based computed tomography has, our knowledge, not been performed. Methods. scans thorax abdomen 50 persons without...
The purpose of this prospective multicenter study was to assess the safety and technical feasibility volumetric Magnetic Resonance-guided High Intensity Focused Ultrasound (MR-HIFU) ablation for treatment patients with symptomatic uterine fibroids. Thirty-three 36 fibroids were treated MR-HIFU ablation. Treatment capability assessed by comparison Non-Perfused Volumes (NPVs) MR thermal dose predicted volumes. Safety determined evaluation complications or adverse events unintended lesions....
Abstract Purpose: To evaluate the influence of choice different combinations b ‐values on ADC and diagnostic performance quantitative diffusion weighted imaging (DWI) in breast lesions. Materials Methods: Seventy‐three patients (90 lesions) underwent 3 Tesla (T) MRI including a DWI‐scan using 0, 150, 499, 1500 s/mm 2 histological analysis. Five were used to calculate , each with sensitivities perfusion effects. The median benign lesions, noninvasive carcinomas invasive five methods compared....
Magnetic resonance-guided high intensity focused ultrasound (MR-HIFU) has recently emerged as an effective treatment option for painful bone metastases. We describe here the first experience with volumetric MR-HIFU palliative of metastases and evaluate technique on three levels: technical feasibility, safety, initial effectiveness.In this observational cohort study, 11 consecutive patients (7 male 4 female; median age, 60 years; age range, 53-86 years) underwent 13 treatments 12 All...
Abstract Purpose This study evaluates the nnU-Net for segmenting brain, skin, tumors, and ventricles in contrast-enhanced T1 (T1CE) images, benchmarking it against an established mesh growing algorithm (MGA). Methods We used 67 retrospectively collected annotated single-center T1CE brain scans training models tumor, ventricle segmentation. An additional 32 from two centers were test performance compared to that of MGA. The was measured using Dice-Sørensen coefficient (DSC), intersection over...
The high frequency of the radiofrequency (RF) fields used in field magnetic resonance imaging (MRI) results electromagnetic variations that can cause local regions to have a large specific absorption rate (SAR) and/or low excitation. In this study, we evaluated use B1 shimming technique which simultaneously improve B+1 homogeneity and reduce SAR for whole body at 7 T. Optimizations four individual anatomies showed reduction up 74% peak values with respect quadrature excitation simultaneous...
In high-field MRI severe problems with respect to B(1) (+) uniformity and specific absorption rate (SAR) deposition pose a great challenge whole-body imaging. this study the potential of phased array transmit coil is investigated simultaneously reduce nonuniformity SAR deposition. This was tested by performing electromagnetic simulations TEM operating at 128 MHz loaded two different homogeneous elliptical phantoms four dielectric patient models. It shown that wave interference circularly...
To evaluate pulsatility and movement along the ascending thoracic aorta using dynamic electrocardiographically-gated 64-slice cine computed tomographic angiography (CTA).Diameter area change center of mass (COM) was determined per cardiac cycle in 15 patients at surgically relevant anatomical levels: (A) 5 mm distal to coronary arteries, (B) proximal innominate artery, (C) halfway up aorta. Additionally, COM 1 cm (level P) 2 Q) from origins innominate, left carotid, subclavian arteries....
Proton resonance frequency shift-based MR thermometry (MRT) is hampered by temporal magnetic field changes. Temporal changes in the susceptibility distribution lead to nonlocal and are, therefore, a possible source of errors. The volume tissue temperature dependent. For water-like tissues, this dependency order 0.002 ppm/°C. fat, it same magnitude as dependence proton electron screening constant water (0.01 ppm/°C). reason, fatty like human breast, expected be prone We aimed quantify...
Vertebral rotation was systematically analyzed in the normal, nonscoliotic thoracic spine of children aged 0 to 16 years. Subgroups were created match infantile, juvenile, and adolescent age groups according criteria Scoliosis Research Society.To determine whether a distinct pattern vertebral transverse plane exists spine.We assume that, once starts deteriorate into scoliotic deformity, it will follow preexisting rotational pattern. Recently, we identified normal adult that corresponds most...
Purpose During MR-guided high-intensity focused ultrasound (HIFU) therapy, absorption in the near field represents a safety risk and limits efficient energy deposition at target. In this study, we investigated feasibility of using T2 mapping to monitor temperature change subcutaneous adipose tissue layers. Methods The dependence reversibility was determined for fresh porcine samples. accuracy evaluated by comparing T2-based measurements with probe readings an ex vivo HIFU experiment....
Abstract In this study, a method is proposed for MRI of the lumen metallic vascular implants, like stents or vena cava filters. The based on reduction artifacts caused by flow, susceptibility, and RF eddy currents. Whereas both flow susceptibility are well understood documented, not. Therefore, present study comprises an in‐depth theoretical explanation factors governing severity these artifacts. It explained that caging inside cage‐like implants disturbances send receive sensitivities due...