introduction: one of the major causes of image non-uniformity in mri is due to the existence of  non-homogeneity in rf receive and transmit. this can be the most effective source of error in  quantitative  studies  in  mri  imaging.  part  of  this  non-homogeneity  demonstrates  the  characteristics of rf coil and part of it is due to the interaction of rf field with the material being  imaged...

Introduction Signal intensity uniformity in a magnetic resonance (MR) image indicates how well the MR imaging (MRI) system represents an object. One of the major sources of image non-uniformity in high-field MRI scanners is inhomogeneity of radio-frequency coil. The aim of this study was to investigate non-uniformity in head, head and neck, and body coils and compare the obtained results to det...

We present the development of a microfluidically cryo-cooled planar coil for magnetic resonance (MR) microscopy. Cryogenically cooling radiofrequency (RF) coils for magnetic resonance imaging (MRI) can improve the signal to noise ratio (SNR) of the experiment. Conventional cryostats typically use a vacuum gap to keep samples to be imaged, especially biological samples, at or near room temperatu...

Parallel magnetic resonance (MR) imaging techniques use multiple receiver coils for data acquisition. Sensitivity responses of these coils usually vary in space and must be estimated via a separate calibration process. We present an algorithm for jointly estimating MR images and coil sensitivity maps from subsampled k-space measurements. We pose the joint estimation problem as the recovery of a...

PURPOSE To compare the imaging time and image quality obtained with whole-heart coronary magnetic resonance (MR) angiography performed with five- and 32-channel coils in healthy subjects and determine the accuracy of MR angiography performed with 32-channel coils in the detection of obstructive coronary artery disease (CAD). MATERIALS AND METHODS The institutional review board approved the st...

For some time it has been recognized that surface-receivercoil designs can enhance certain aspects of magnetic resonance (MR) signal detection [1] . During the last several years, surface coils have been the predominant means of recording the MR spectra of metabolites from animals and humans in vivo [2-4]. Efforts to produce surface-coil images at low magnetic field strengths have been undertak...

BACKGROUND AND PURPOSE Conventional platinum coils cause imaging artifacts that reduce imaging quality and therefore impair imaging interpretation on intraprocedural or noninvasive follow-up imaging. The purpose of this study was to evaluate imaging characteristics and artifact production of polymeric coils compared with standard platinum coils in vitro and in vivo. MATERIALS AND METHODS Poly...

Background/introduction Signal-to-Noise Ratio (SNR) can be increased in Magnetic Resonance Imaging (MRI) using Radio Frequency (RF) coils. Of all the options for increasing SNR, coils provide the greatest gains for the dollars spent. Coils for 1.5 and 3 Tesla MRI systems consist of conductive loops that are tuned to resonate at the fundamental frequency associated with the field strength of the...

Parallel imaging techniques have developed very rapidly, and realization of their full potential has required the design of magnetic resonance (MR) scanners with ever-increasing numbers of receiver channels (32 to 128). In particular, 1.5- and 3-Tesla fast MR imaging applications are now used in everyday clinical practice. Both strengths require maximum achievable signal-to-noise ratio (SNR) an...

In this work, we propose and investigate a volume coil array design method using different types of birdcage coils for MR imaging. Unlike the conventional radiofrequency (RF) coil arrays of which the array elements are surface coils, the proposed volume coil array consists of a set of independent volume coils including a conventional birdcage coil, a transverse birdcage coil, and a helix birdca...