Ibrahim El-Sayed H, Stuber Matthias, Kraitchman Dara L, Weiss Robert G, Osman Nael F
Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, Maryland 21287, USA.
Magn Reson Med. 2007 Oct;58(4):843-9. doi: 10.1002/mrm.21390.
The combination of cardiac viability and functional information enhances the identification of different heart tissues in the setting of ischemic heart disease. A method has recently been proposed for obtaining black-blood delayed-enhancement (DE) viability images using the stimulated-echo acquisition mode (STEAM) MRI pulse sequence in a single short breathhold. The method was validated against conventional inversion-recovery (IR) DE images for identifying regions of myocardial infarction (MI). The method was based on the acquisition of three consecutive images of the same anatomical slice. One image has T(1)-weighted contrast in which infarction appears bright. The two other images are used to construct an anatomical image of the heart, which is combined with the first image to produce a black-blood viability image. However, using appropriate modulation and demodulation frequencies, the latter two images bear useful information about myocardial deformation that results in a cardiac strain-encoding (SENC) functional image. In this work, a method is proposed for obtaining three consecutive SENC images in a single acquisition that can be combined to produce a composite image of the heart, which shows both functional and viability information. The proposed technique reduces scan time by one-half, compared with separate acquisitions of functional and viability images, and alleviates misregistration problems caused by separate breathholds.
心脏存活能力与功能信息的结合，可增强在缺血性心脏病背景下对不同心脏组织的识别。最近有人提出一种方法，可在单次短暂屏气时使用刺激回波采集模式（STEAM）MRI脉冲序列获取黑血延迟强化（DE）存活能力图像。该方法针对传统反转恢复（IR）DE图像进行了验证，用于识别心肌梗死（MI）区域。该方法基于对同一解剖切片的三个连续图像的采集。其中一幅图像具有T(1)加权对比度，梗死区域在其中显示为亮区。另外两幅图像用于构建心脏的解剖图像，该解剖图像与第一幅图像相结合以生成黑血存活能力图像。然而，通过使用适当的调制和解调频率，后两幅图像承载了有关心肌变形的有用信息，从而生成心脏应变编码（SENC）功能图像。在这项工作中，提出了一种在单次采集中获取三个连续SENC图像的方法，这些图像可组合生成心脏的复合图像，该复合图像同时显示功能和存活能力信息。与分别采集功能图像和存活能力图像相比，所提出的技术将扫描时间减少了一半，并减轻了由单独屏气引起的配准错误问题。
