Ortendahl D A, Hylton N, Kaufman L, Watts J C, Crooks L E, Mills C M, Stark D D
Radiology. 1984 Nov;153(2):479-88. doi: 10.1148/radiology.153.2.6091173.
The response of different magnetic resonance (MR) techniques to tissue parameters - T1, T2, and N(H) - is a determinant of clinical efficacy. The large possible number of imaging techniques and range of variable parameters for each make it difficult to perform exhaustive evaluations in a single patient or even in animal models. In addition, changes in operating magnetic field strength change the relaxation times sufficiently so that the efficacy of a technique at a given field does not imply similar results at another field value. Tools are demonstrated that permit the evaluation of the efficacy of any model of response to tissue parameters, and also allow the investigation of the effects of changing magnetic field. Global maps of signal difference between tissues as well as calculated images are obtainable from a minimally sufficient data set. These tools serve as an important adjunct to experimental work.
不同磁共振（MR）技术对组织参数——T1、T2和N(H)——的反应是临床疗效的一个决定因素。每种技术可能的成像技术数量众多且可变参数范围广，这使得在单个患者甚至动物模型中进行详尽评估变得困难。此外，操作磁场强度的变化会使弛豫时间发生足够大的改变，以至于某一给定磁场下一种技术的疗效并不意味着在另一个场值下会有类似结果。文中展示了一些工具，这些工具可以评估对组织参数的任何反应模型的疗效，还能研究磁场变化的影响。从最少的足够数据集中可获得组织间信号差异的全局图以及计算图像。这些工具是实验工作的重要辅助手段。
