Brüning R, Weber J, Wu R H, Kwong K K, Hennig J, Reiser M
Institut für Radiologische Diagnostik, Ludwig-Maximilians-Universität München.
Radiologe. 1995 Dec;35(12):902-10.
In this review, the clinical utility of echoplanar techniques in MRI of the brain is discussed. Comparison of high-resolution EPI with SE/turbo-SE shows high image quality of EPI in the supratentorial brain. In the infratentorial region, however, susceptibility artifacts limit image quality. For the assessment of neuronal brain activation utilizing the intrinsic contrast of blood (BOLD), EPI has definite advantages over other techniques of functional MRI. Due to its superior temporal resolution and multislice capabilities, EPI allows for analysis of complex neuronal activation patterns. Diffusion imaging benefits from the lack of bulk motion artifacts and serves primarily to detect early stroke. Three methods of perfusion imaging (rel. blood volume, rel. blood flow) are discussed: the susceptibility artifact method (T2*), the relaxitivity method (T1), and the signal-labelling technique (STAR). Perfusion imaging may have a clinical impact in the assessment of brain tumors and cerebral ischemia.
在本综述中，讨论了脑磁共振成像中回波平面技术的临床应用。高分辨率回波平面成像（EPI）与自旋回波（SE）/快速自旋回波（turbo-SE）的比较显示，EPI在幕上脑区具有高图像质量。然而，在幕下区域，磁敏感伪影限制了图像质量。对于利用血液固有对比（血氧水平依赖性功能磁共振成像，BOLD）评估神经元脑激活，EPI相对于其他功能磁共振成像技术具有明显优势。由于其卓越的时间分辨率和多层成像能力，EPI允许分析复杂的神经元激活模式。扩散成像受益于缺乏整体运动伪影，主要用于检测早期卒中。讨论了三种灌注成像方法（相对血容量、相对血流）：磁敏感伪影法（T2*）、弛豫率法（T1）和信号标记技术（STAR）。灌注成像在脑肿瘤和脑缺血评估中可能具有临床意义。
