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磁共振成像原理磁共振成像(MRI)是利用射频脉冲对置于磁场中的含有自旋不为零的原子核的物质进行激发,发生核磁共振,用感应线圈采集磁共振信号,按一定数学方法进行处理而建立的一种数字图像。含单数质子的原子核,例如人体内广泛存在的氢原子核,其质子有自旋运动,带正电,产生磁矩,有如一个小磁体。小磁体自旋轴的排列无一定规律。但如在均匀的强磁场中,则小磁体的自旋轴将按磁场磁力线的方向重新排列。用特定频率的射频脉冲进行激发,作为小
Magnetic Resonance Imaging Principle Magnetic resonance imaging (MRI) is the use of radio frequency pulses placed in the magnetic field containing spin non-zero atomic nuclei material excitation, nuclear magnetic resonance, magnetic induction coil with the acquisition signal, according to a certain mathematical method Processing and the establishment of a digital image. Nuclei that contain a single proton, such as the hydrogen nuclei that are widely present in the human body, have proton spin movements that are positively charged and generate magnetic moments that resemble a small magnet. Small magnet spin axis arrangement is not a certain law. However, if in a uniform strong magnetic field, the spin axis of the small magnet will be rearranged in the direction of the magnetic field lines. With a specific frequency of radio frequency pulse excitation, as small