Amanuma M, Kimura T, Takizawa O, Kozawa E, Enomoto K, Watabe T, Heshiki A
Department of Radiology, Saitama Medical School.
Nihon Igaku Hoshasen Gakkai Zasshi. 1995 Mar;55(4):222-7.
To suppress image degradation due to respiratory corruption during breath holding, a method of reordering of phase encoding was introduced in three-dimensional MR imaging. Without trade-offs in SNR, CNR, and examination time, the method provided a significant reduction of respiratory motion-induced artifacts both in phantom and in vivo experiments. More than twenty seconds of breath holding ensured acceptable image quality regardless of respiratory motion thereafter. Signal intensity change during data acquisition altered the obtained image contrast compared with that of standard sequential linear phase encoding. This technique can be readily implemented on standard two-and three-dimensional pulse sequences and will improve image quality when a patient cannot hold his/her breath during the whole imaging period.
为了抑制屏气期间呼吸干扰导致的图像退化,在三维磁共振成像中引入了一种相位编码重排方法。该方法在不影响信噪比、对比噪声比和检查时间的情况下,在体模和体内实验中均显著减少了呼吸运动引起的伪影。此后,无论呼吸运动如何,超过20秒的屏气可确保获得可接受的图像质量。与标准的顺序线性相位编码相比,数据采集期间的信号强度变化改变了所获得的图像对比度。该技术可轻松应用于标准的二维和三维脉冲序列,并且当患者在整个成像期间无法屏气时,可提高图像质量。