Helmholtz-pair transmit coil with integrated receive array for high-resolution MRI of trabecular bone in the distal tibia at 7T.

A Helmholtz-pair local transmit RF coil with an integrated four-element receive array RF coil and foot immobilization platform was designed and constructed for imaging the distal tibia in a whole-body 7T MRI scanner. Simulations and measurements of the B(1) field distribution of the transmit coil are described, along with SAR considerations for operation at 7T. Results of imaging the trabecular bone of three volunteers at 1.

Prostate MR imaging at 3T with a longitudinal array endorectal surface coil and phased array body coil.

Purpose: To demonstrate the feasibility of using a double loop phased array endorectal coil combined with a phased array body coil to image the prostate at 3T.

Materials And Methods: We designed and constructed a novel prostate coil employing two arrayed 4.0 x 5.

Continuous ASL (CASL) perfusion MRI with an array coil and parallel imaging at 3T.

The purpose of this work was to assess the feasibility and efficacy of using an array coil and parallel imaging in continuous arterial spin labeling (CASL) perfusion MRI. An 8-channel receive-only array head coil was used in conjunction with a surrounding detunable volume transmit coil. The signal to noise ratio (SNR), temporal stability, cerebral blood flow (CBF), and perfusion image coverage were measured from steady state CASL scans using: a standard volume coil, array coil, and array coil with 2- and 3-fold accelerated parallel imaging.

Cardiac imaging at 4 Tesla.

Although higher magnetic field strength is a means to increase SNR in MRI, cardiac imaging has been difficult at high fields due to decreased RF penetration. Using a tailored cardiac coil constructed of two transmit surface coils with a four-element multicoil for signal reception, the authors demonstrate high-quality heart images acquired on a 4-T scanner. These images show an increase in SNR of approximately 2.

A spiral volume coil for improved RF field homogeneity at high static magnetic field strength.

Biological samples have a high dielectric constant that can shorten RF wavelengths by a factor of 8 relative to the vacuum. At high field strengths, finite wavelength effects within larger samples are the dominant cause of RF field nonuniformity. A coil design is presented that can reduce and even eliminate this inhomogeneity; 4-T images in phantoms and in the head of a normal volunteer are presented, which demonstrate improved homogeneity relative to a standard coil.