Thomas J D
Magnetic Resonance Imaging/Computed Tomography Center, St. Anthony Hospital, Oklahoma City, Okla.
Radiol Technol. 1996 Mar-Apr;67(4):297-306.
Two populations of hydrogen protons exist in magnetic resonance imaging: free protons and bound protons. Bound protons do not contribute to normal MR signal because they resonate somewhat off the center frequency of water. A special pulse sequence called magnetization transfer contrast (MTC) was developed to compensate for this off-resonance limitation. A saturation transfer of bound protons occurs during MTC, enabling a transfer of energy to the free proton pool and thereby contributing to the overall MR signal. This article describes MTC, reviews its applications and explains how it improves lesion conspicuity, small vessel detail and background suppression.
自由质子和结合质子。结合质子对正常的磁共振信号没有贡献，因为它们的共振频率略偏离水的中心频率。一种名为磁化传递对比（MTC）的特殊脉冲序列被开发出来以弥补这种失谐限制。在MTC过程中会发生结合质子的饱和传递，使得能量转移到自由质子池，从而对整体磁共振信号有所贡献。本文介绍了MTC，回顾了其应用，并解释了它如何提高病变的清晰度、小血管细节及背景抑制。
