The ability to detect brain anatomy and pathophysiology with MRI is limited by the contrast-to-noise ratio (CNR), which depends on the contrast mechanism used and the spatial resolution. In this work, we show that in MRI of the human brain, large improvements in contrast to noise in high-resolution images are possible by exploiting the MRI signal phase at high magnetic field strength. Using gra...

The global use of magnetic resonance imaging (MRI) is constantly growing and the field strengths increasing. Yet, only little data about harmful biological effects caused by MRI exposure are available and published research analyzing the impact of MRI on DNA integrity reported controversial results. This in vitro study aimed to investigate the genotoxic and cytotoxic potential of 7 T ultra-high...

INTRODUCTION: Sodium MRI shows promise in assessing cartilage health [1], characterizing tumors [2], detecting abnormal sodium levels in the kidneys [3], and assessing tissue damage following stroke [4]. However, relatively low Na concentrations in biological tissues, a rapid biexponential signal decay, and a low gyromagnetic ratio make sodium MRI challenging. Recent improvements in MRI hardwar...

Neurological, CT and high-field (1.5T) magnetic resonance imaging (MRI) data were correlated in 6 patients previously clinically diagnosed as having suffered small vertebrobasilar infarct. MRI demonstrated infarcts in areas where CT was nearly always negative. MRI allowed very precise clinico-topographic correlations and appears to be the preferred imaging technique in vertebrobasilar infarcts.

Cardiovascular magnetic resonance imaging (MRI) has gained widespread acceptance for the assessment of cardiovascular disease (1-4). Recent developments in 3.0 T MRI technology have led to an increased interest in high-field cardiac imaging. Because the signal-to-noise (SNR) scales approximately linearly with the magnetic field strength, B0, an improvement in the SNR can be expected at 3.0 T in...

Field inhomogeneities in Magnetic Resonance Imaging (MRI) can cause blur or image distortion as they produce off-resonance frequency at each voxel. These effects can be corrected if an accurate field map is available. Field maps can be estimated starting from the phase of multiple complex MRI data sets. In this paper we present a technique based on statistical estimation in order to reconstruct...

Background Insight of physiological processes and cellular metabolism makes 23Na-MRI conceptually appealing as non-invasive imaging discipline. Several studies report the applicability of 23Na-MRI for the detection and assessment of acute and chronic heart disease due to increased sodium concentration after myocardial infarctions. Bi-exponential decay of the signal and a low SNR compared to 1H-...

Introduction: The objective of this work is to study the ability of MRI normoxic polymer gel dosimetry system to be used to verify the calculated dose distribution, in a simple geometry, in clinical radiotherapy. Materials and Methods:  Initially, 2 liters of the normoxic MAGAT polymer gel was prepared and then poured into two cylindrical Perspex phantom (simu...

Health care staff who operate magnetic resonance imaging (MRI) devices are exposed to a static magnetic field of significant spatial heterogenity always produced by MRI magnets during the whole shift. They can also be exposed to pulses of a time-varying magnetic field (gradient field) present only during patients' examinations. The level of the workers' exposure depends both on the type of the ...

INTRODUCTION Diffusion tensor MRI (DT-MRI) provides a discrete representation of the diffusion tensor field ofwater in living tissues. A graphical means to display the diffusion tensor field, '[\]is to construct diffusion ellipsoid maps or images (1). Moreover, from the diffusion tensor field, one can infer the fiber-tract direction field in some anisotropic tissues (1). 1n white matter and ske...