Wang Chengbo, Miller G Wilson, Altes Talissa A, de Lange Eduard E, Cates Gordon D, Mata Jaime F, Brookeman James R, Mugler John P
Center for In-vivo Hyperpolarized Gas MR Imaging, Department of Radiology, University of Virginia School of Medicine, Charlottesville, Virginia 22908, USA.
Magn Reson Med. 2008 Mar;59(3):673-8. doi: 10.1002/mrm.21543.
A stimulated-echo-based technique was developed to measure the regional apparent diffusion coefficient (ADC) of hyperpolarized 3He during a single breathhold for diffusion times of 25 ms or greater. Compared to previous methods, a substantially shorter minimum diffusion time was achieved by decoupling diffusion sensitization from image acquisition. A hyperpolarized-gas phantom was used to validate the method, which was then tested in four healthy subjects in whom regional ADC maps were acquired with diffusion times of 50, 200, and 1500 ms and a tag wavelength of 5 or 10 mm. ADC values from healthy subjects were in good agreement with reported literature values and decreased with increasing diffusion time. Mean ADC values were approximately 0.07, 0.03, and 0.015 cm2/s for diffusion times of 50, 200, and 1500 ms, respectively. ADC maps were generally homogeneous, with similar mean values when measured with the same parameters in different subjects.
开发了一种基于受激回波的技术，用于在单次屏气期间测量超极化3He在25 ms或更长扩散时间的区域表观扩散系数（ADC）。与以前的方法相比，通过将扩散敏感化与图像采集解耦，实现了显著更短的最小扩散时间。使用超极化气体模型对该方法进行验证，然后在四名健康受试者中进行测试，在这些受试者中，采集了扩散时间为50、200和1500 ms且标记波长为5或10 mm的区域ADC图。健康受试者的ADC值与已发表文献值高度一致，并随扩散时间增加而降低。对于扩散时间分别为50、200和1500 ms，平均ADC值分别约为0.07、0.03和0.015 cm2/s。ADC图通常是均匀的，在不同受试者中使用相同参数测量时具有相似的平均值。
