Boxerman J L, Mosher T J, McVeigh E R, Atalar E, Lima J A, Bluemke D A
Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
Radiographics. 1998 May-Jun;18(3):543-64. doi: 10.1148/radiographics.18.3.9599382.
A "one-stop shop" for evaluating cardiac disease with magnetic resonance (MR) imaging is progressing toward clinical reality and promises to have a major effect on the care of patients with cardiac disease. T1-weighted conventional spin-echo imaging gated to the cardiac cycle yields good anatomic detail but requires long imaging times and provides only static images of a single cardiac phase. Fast MR imaging with electrocardiographically (ECG) gated, low-flip-angle, segmented k-space gradient-recalled-echo (GRE) sequences provides excellent image quality with sufficiently high temporal resolution to "freeze" cardiac motion. Segmented k-space sequences improve on standard ECG-gated GRE sequences by allowing many cardiac phases, or frames of a cine sequence, to be imaged in a single breath hold with prospective cardiac gating. As commercial implementations of segmented k-space imaging become more widely available, the applications of this technique are expanding from research protocols to include many clinical applications in the heart and great vessels. Such applications include evaluation of vascular anatomy (coronary angiography, aortic disease, aberrant vessels, vascular access), cardiac anatomy (congenital anomalies, right ventricular dysplasia, constrictive pericarditis, valvular function), myocardial perfusion, and myocardial wall motion.
利用磁共振（MR）成像评估心脏疾病的“一站式服务”正逐步走向临床应用，并有望对心脏病患者的护理产生重大影响。门控于心动周期的T1加权常规自旋回波成像能提供良好的解剖细节，但成像时间长，且仅能提供单个心动相位的静态图像。采用心电图（ECG）门控、低翻转角、分段k空间梯度回波（GRE）序列的快速MR成像，能提供具有足够高时间分辨率的优异图像质量，以“冻结”心脏运动。分段k空间序列通过在前瞻性心脏门控下在一次屏气中对多个心动相位或电影序列的帧进行成像，对标准ECG门控GRE序列进行了改进。随着分段k空间成像的商业应用越来越广泛，该技术的应用正从研究方案扩展到包括心脏和大血管的许多临床应用。这些应用包括血管解剖评估（冠状动脉造影、主动脉疾病、异常血管、血管通路）、心脏解剖评估（先天性异常、右心室发育不良、缩窄性心包炎、瓣膜功能）、心肌灌注和心肌壁运动评估。
