Conveners
Fri-Mo-Po.03 - Magnets for MRI
- Bin He (Siemens (ShenZhen) Magnetic Resonance Ltd.)
- Vijay Soni (GE HealthCare Technology & Innovation Center)
Magnetic Resonance Imaging (MRI) is a technique that generates high-resolution volumetric images of the body using a strong magnetic flux density. The image quality directly depends on the magnetic field homogeneity. Commercial superconducting magnets have a magnetic field homogeneity below two parts per million (ppm) and use Nb-Ti magnets. However, they need to be cooled at 4 K. It is costly...
The conventional iron matrix shimming method is sensitive to positional variations, which significantly impacts the magnetic field homogeneity of small-aperture 7T/54mm cryogen-free MRI superconducting magnets. This study aims to develop a robust, adjustable shimming method to improve magnetic field uniformity and precisely cancel low-order harmonics in these sensitive systems. A set of...
The Brazilian Center for Research in Energy and Materials (CNPEM) has built a medium field Magnetic Resonance Image (MRI) prototype as part of an overall effort on the in-house development of fundamental MRI technology know-how. The system is comprised of a permanent-magnet-based dipole, a set of planar coils for gradient field generation and a radiofrequency system with a...
In this paper, we present the design and test results of a low-AC-loss Nb3Sn model coil developed to validate key enabling technologies for a fast-switching-field magnetic resonance imaging (MRI) magnet concept that can change the magnetic field very quickly in time, within 1 second, between significantly different field strengths: a high field (3 T) for relaxometry and prepolarization and a...
Abstract：High field magnetic resonance imaging (HF-MRI) systems can achieve higher image resolution and sensitivity, resulting in better image quality and more biological information, which has significant value in life science and clinical medicine applications. The key to high field magnetic resonance imaging systems is the high homogeneous superconducting magnets, and active homogenization...
A low-cryogen compact 7T MRI system(C7T) dedicated for brain imaging has been developed at the GE HealthCare Technology and Innovation Center. The C7T magnet utilizes a fully sealed helium cooling system. Only 12 liters of liquid helium are condensed at 4.2 K from high pressure gaseous helium charged at room temperature. The C7T magnet is designed for a B0-field homogeneity <1.0 ppm in a 26-cm...
