Boxt L M
Division of Cardiac Radiology, College of Physicians and Surgeons of Columbia University, New York, New York, USA.
Magn Reson Imaging Clin N Am. 1996 May;4(2):253-68.
Spin echo and gradient reversal MR imaging techniques provide a noninvasive means of analyzing the state of ventricular myocardium in patients with atherosclerotic and valvular heart disease. Local ischemic changes are manifested on spin echo MR examination as loci of increased signal intensity, most likely representing accumulation of local myocardial edema. Administration of intravenous paramagnetic contrast material further enhances local changes, increasing the sensitivity of MR methods for detecting such change. Application of spin echo and gradient reversal techniques also provides direct demonstration of morphologic changes in chamber volume and myocardial wall thickness and thickening, the sequelae of ischemic and acquired valvular heart disease, as well as direct demonstration of abnormal blood flow across diseased valves. Newer methods of analysis of these flow abnormalities provide information concerning pressure gradients across stenotic valves and regurgitant fractions across insufficient valves. Thus, application of MR imaging techniques provides clinically relevant information needed by referring clinicians for the management of patients with acquired heart disease.
自旋回波和梯度反转磁共振成像技术为分析动脉粥样硬化性和瓣膜性心脏病患者的心室心肌状态提供了一种非侵入性方法。局部缺血性改变在自旋回波磁共振检查中表现为信号强度增加的部位，很可能代表局部心肌水肿的积聚。静脉注射顺磁性造影剂进一步增强局部改变，提高了磁共振方法检测此类改变的敏感性。自旋回波和梯度反转技术的应用还能直接显示心室容积、心肌壁厚度和增厚的形态学改变，这些是缺血性和后天性瓣膜性心脏病的后遗症，以及直接显示病变瓣膜处的异常血流。这些血流异常的更新分析方法提供了有关狭窄瓣膜跨瓣压力梯度和反流瓣膜反流分数的信息。因此，磁共振成像技术的应用为临床医生管理后天性心脏病患者提供了所需的临床相关信息。
