Henkelman R M, Hardy P, Poon P Y, Bronskill M J
Radiology. 1986 Dec;161(3):727-34. doi: 10.1148/radiology.161.3.3786723.
For magnetic resonance (MR) imaging studies in which the diagnosis is dependent on image contrast, it is essential that an optimized imaging technique be used. Using detection of hepatic metastases as an example, the authors describe a rational strategy for optimizing MR imaging technique. First, for a single patient with proved hepatic metastases, a variety of imaging sequences is discussed and evaluated, leading to characterization of the patient's hepatic tissues. Then the characteristics of the tissues of a representative patient population are presented. These are used to determine two optimal pulse sequences that maximize the achievable signal difference-to-noise ratio achievable in a fixed imaging time. The recommended imaging sequence for detection of hepatic metastases at 0.15 T is either a three-dimensional volume spin-echo (SE) sequence with echo time (TE) = 12 msec and repetition time (TR) = 184 msec or a multisection inversion recovery sequence with TE = 22 msec, inversion time = 250 msec, and TR = 1,375 msec. The variation of this optimum pulse sequence with field strength is also presented.
对于诊断依赖于图像对比度的磁共振（MR）成像研究，使用优化的成像技术至关重要。作者以肝转移瘤的检测为例，描述了一种优化MR成像技术的合理策略。首先，对于一名已证实患有肝转移瘤的患者，讨论并评估了多种成像序列，从而对患者的肝组织进行了特征描述。然后给出了一组具有代表性的患者群体的组织特征。这些特征用于确定两个最佳脉冲序列，这两个序列能在固定成像时间内使可实现的信号差与噪声比最大化。在0.15 T场强下检测肝转移瘤的推荐成像序列，要么是回波时间（TE）= 12毫秒、重复时间（TR）= 184毫秒的三维容积自旋回波（SE）序列，要么是TE = 22毫秒、反转时间 = 250毫秒且TR = 1375毫秒的多层面反转恢复序列。还给出了该最佳脉冲序列随场强的变化情况。
