Robust Cardiac Self-Gating For Fetal Cardiac MRI

描述(申请人提供)：先天性心脏病(CHD)是北美最常见的先天性缺陷，每1000名活产儿中就有8名受到影响。CHD的产前诊断可以改善和更知情地决定患者在出生前和出生后的管理。在目前的临床实践中，诊断冠心病通常使用超声检查心脏的解剖和功能以及通过瓣膜和大血管的血流。然而，由于各种原因，超声在某些患者中的使用受到限制。在这些情况下，胎儿心脏MRI是一种很有前途的替代成像方式，因为它具有良好的软组织对比度和缺乏辐射暴露。在过去的二十年里，心脏MRI技术的进步使得心脏MRI在临床上得到了更广泛的使用。然而，由于各种原因，MRI在胎儿心脏成像中的应用仍处于起步阶段。除了胎儿成像对空间分辨率的更严格要求外，一个主要障碍是缺乏强大的心脏运动门控技术。在心脏磁共振成像中，图像采集通常使用心电或外周脉冲信号与心脏周期同步，以最大限度地减少心脏运动引起的伪影和图像模糊，或者获得心脏相位分辨率图像。然而，这些信号根本不适用于胎儿核磁共振。因此，要将胎儿心脏MRI应用于临床，需要一种稳健的心脏门控策略。该项目的总体目标是开发能够可靠地提供心脏运动自门控信号的技术，用于胎儿心脏MRI。在这个项目中，我们提出了几项可以常规使用的技术创新，以获得可靠的胎儿心脏自门信号。然后，将对一组孕妇进行评估，这些孕妇因怀疑患有先天性心脏病而被转诊至胎儿超声检查。

DESCRIPTION (provided by applicant): Congenital heart disease (CHD) is the most common congenital defect affecting eight per thousand live births in North America. Prenatal diagnosis of CHD allows for improved and better informed decisions on patient management before and after birth. In current clinical practices, an ultrasound examination of the anatomy and function of the heart as well as the blood flow through the valves and great vessels is usually used for diagnosis of CHD. However, the use of ultrasound is limited in certain patients due to various reasons. In these cases, fetal cardiac MRI is a promising alternative imaging modality due to its excellent soft tissue contrast and lack of radiation exposure. Advances in cardiac MRI technology in the last two decades have enabled more widespread use of cardiac MRI in the clinical setting. However, the use of MRI for fetal cardiac imaging remains in its infancy due to various reasons. Aside from the more stringent requirement on spatial resolution for fetal imaging, a major impediment is lack of a robust cardiac motion gating technology. In cardiac MRI, the image acquisition is typically synchronized to the cardiac cycle using either an electrocardiogram (ECG) or peripheral pulse signal to minimize the artifacts and image blurring resulting from cardiac motion or to obtain a cardiac phase resolved image. However, these signals are simply not available for fetal MRI. Therefore, a robust cardiac gating strategy is needed for fetal cardiac MRI to be used clinically. The overall goal of this project is to develop techniques that can reliably provide a cardiac motion self- gating signal for use in fetal cardiac MRI. In this project, we propose several technical innovations that can be used routinely to obtain reliable fetal cardiac self-gating signal. The developed strategies will then be evaluated on a cohort of pregnant women who are referred to fetal ultrasound for suspected congenital heart disease.