Enhancement of the Spatial Resolution for the Temperature Sensing System of the 7 Tesla Magnetic Resonance Imaging Scanner

The MRI scanner with an ultrahigh magnetic field of 7T not only increases the image resolution but it also increases the Specific Absorption Rate (SAR) of the patient. In other words, the body temperature of the patient increases due to the absorption of heat produced by the 7T MRI scanner. This is dangerous for the health of the patient. In...

Three-Dimensional Contrast Source Inversion-Electrical Properties Tomography: 3D CSI-EPT

The electrical properties (EPs) conductivity and permittivity of biological tissue inside the human body provide diagnostic information of those tissues. This allows differentiation between tumors and healthy tissue and quantification of the specific absorption rate (SAR) of the tissues. Visualizing the EPs based on measurable magnetic radio...

Accelerating Diffusion-Weighted Chemical Shift Imaging using Compressed Sensing with Parameter Mapping

Diffusion-weighted chemical shift imaging (DW-CSI) is a recently developed MRI modality that enables radiologists to reveal the diffusion properties of small molecules that act in metabolic reactions in-vivo. In order to extract this diffusion information from a patient, DW-CSI requires approximately one hour of scan time. This extensive scan...

Image Reconstuction in MRI: The Possibilities of Portable Low-cost MRI Scanners

Hydrocephalus is one of the most common abnormalities affecting the nervous system of children around the globe. Especially in developing countries hydrocephalus is a large problem. It is often left untreated resulting in suffering, brain damage, developmental delays and ultimately death. This makes an early detection more opportune than ever....

Computer-Aided Comparative Assessment of Inflammatory Lesions in MRI of the Spine in Axial Spondyloarthritis Patients

Detection of inflammatory lesions in magnetic resonance imaging (MRI) of the spine in axial Spondyloarthritis (SpA) patients is a labor-intensive task. Current scoring methods often require an expert reader to visually assess 23 vertebral units (VU) on multiple MRI slices. Furthermore, monitoring of progressive changes consists of a manual...

Development of a Two-Dimensional Resonator Design Tool

One of the engineering challenges in high-field MRI is to have a homogeneous distribution of the RF magnetic field inside human tissue. In this project we develop a design tool for a HEM wrist applicator that has the ability to generate a homogeneous magnetic field inside human wrist. By taking into account the dominant RF scattering effects...

Assessing the MR compatibility of dental retainer wires at 7 tesla

The radio frequent (RF) safety of dental retainer wires during Magnetic Resonance Imaging at 7 tesla has been investigated using electromagnetic simulations and thermal measurements on a phantom model. In the Netherlands up to 40% of the younger adults have such a dental retainer wire, which at the moment is listed as a contraindication for 7 T...

Homogeneous RF Field Distribution Optimization in 3T Abdominal Imaging

The appearance of severe signal drop-outs in abdominal Magnetic Resonance Imaging at 3 Tesla arises primarily from areas of very low magnetic flux density B1 of the transmit field in the body, and is problematic in both obese as well as very thin subjects. In this study, we show how thin patient-friendly pads containing new high permittivity...

Hartslagsensor voor 7 T MRI Cardiac Triggering

Voor het maken van scans van het cardiovasculair gebied is het noodzakelijk de MRI-scanner te synchroniseren met de hartslagcyclus. Dit wordt cardiac triggering genoemd. Door de hoge magnetische veldsterkte treden synchronisatiefouten op, waardoor de scans erg onduidelijk en daardoor onbruikbaar worden. Het doel van dit onderzoek was het...

Particle-based Visualization of Soft-Tissue: Deformation in the Human Orbit

Orbital fat is the soft tissue inside the eye socket, or orbit, that surrounds the eye muscles, eyeball, optic nerve and blood vessels. It plays an important role in the mechanical operation of the eye during eyeball rotation. Knowledge of how this orbital fat behaves is limited. It is important for surgeons to improve this knowledge to make...

Direct and comparative visualization techniques for HARDI Data

DWI is an MRI imaging technique used to gain information concerning the diffusion process in tissue. Using DTI techniques, a diffusion profile can be constructed for fiber tract analysis. Recently developed HARDI techniques increase the detail to visualization on the process of diffusion. While HARDI reconstruction methods are used to model the...