Gradient Coil of Permanent Magnet Mini-Magnetic Resonance Imager and Image Quality

Abstract

Abstract:

Effects of gradient field linearity on the quality of images acquired on a permanent magnet mini-magnetic resonance imager were analyzed by theoretical analyses and numerical simulation. It was shown that gradient field with high linearity is a prerequisite to obtain high-quality images of small animals, such as mice, on permanent magnet, low field strength micro-magnetic resonance imagers. The gradient field linearity specification reported in the literature is too low to acquired high-quality mouse images. The image quality could not be improved by software compensation methods. The newly developed gradient field coil with high linear property and our independent intellectual property was also presented. The optimized gradient coil has been installed on our instrument, and yielded a better quality image.

Key words: MRI, Permanent Magnet Mini-mgnetic 3D Resonance Imager, linearity, gradient coil, simulation

CLC Number:

R318.6
R332

HOU Shu-Lian, XIE Huan-Tong, HOU Xiao-Wen, LI Shi-Yu, CHEN Wei. Gradient Coil of Permanent Magnet Mini-Magnetic Resonance Imager and Image Quality[J]. Chinese Journal of Magnetic Resonance, 2012, 29(4): 508-520.

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