Free-breathing and simultaneous multislice cine DENSE myocardial strain imaging

项目总结 在过去的10年里，心肌应变成像的使用和价值一直在增加。其中 许多应用，最突出的包括：(A)评估癌症患者的心脏毒性 化疗，(B)主动脉狭窄的预后和危险分层，以及(C)诊断和预后 未分化的左心室肥厚。我们已经开发了具有激励的运动位移编码 ECHO(密集)应变MRI，与其他部位共享该方法，并将其应用于患者选择和手术 指导心脏再同步治疗(CRT)治疗心力衰竭(HF)。电影密度是高度准确的和 它可重复性地对整体和节段性心肌应变进行量化，正在成为金标准。 技术，主要制造商正在实施这一技术。然而，目前的电影密度成像需要 多次屏气采集或使用隔膜进行低效和不便的自由呼吸采集- 这两种方法都不太适合快速有效的多参数心脏磁共振成像 或用于屏气治疗有困难的病人。此外，在线应变分析是 不可用，因此此任务在工作站上脱机执行。有了这些限制，更方便 经常使用像要素追踪这样的方法，即使它们不太准确，重复性较差 节段性分析和/或预后较差。这个项目将把电影密度发展成一种保持高密度的方法 精确度和重现性好，而且速度快，使用方便。为了实现这一目标，我们提出了四个具体的建议 目标。在目标1中，我们将开发一种高效的自导航自由呼吸电影致密方法，在目标2中，我们将 将使用同步多切片方法开发加速电影密度。目标1和目标2中的方法将 结合在一起，以实现加速自由呼吸成像。在目标3中，我们将开发全自动的方法 位移和应变分析，实现了在线应变映射。最后，在目标4中，我们将 在计划接受CRT的健康志愿者和心力衰竭患者身上验证AIMS 1-3中开发的方法。 总之，该项目将产生一种快速、可重复、方便和有效的心肌应变成像 该方法将广泛应用于心脏成像领域。

Project summary The use and value of myocardial strain imaging have been increasing during the past 10 years. Among many applications, the most prominent include (a) the evaluation of cardiotoxicity in cancer patients undergoing chemotherapy, (b) prognosis and risk stratification in aortic stenosis, and (c) diagnosis and prognosis in undifferentiated left ventricular hypertrophy. We have developed Cine Displacement Encoding with Stimulated Echoes (DENSE) strain MRI, shared the method with other sites, and applied it to patient selection and procedure guidance in cardiac resynchronization therapy (CRT) for heart failure (HF). Cine DENSE is highly accurate and reproducible for the quantification of global and segmental myocardial strain, it is emerging as a gold standard technique, and it is being implemented by major manufacturers. However, current cine DENSE imaging requires multiple breathhold acquisitions or inefficient and inconvenient free-breathing acquisitions using diaphragm- based navigators, and neither approach is well suited for a rapid and efficient multiparametric cardiac MRI protocol or for sick patients with difficulty with breathhold-based protocols. In addition, inline strain analysis is not available and thus this task is performed offline on a workstation. With these limitations, more convenient methods such as feature tracking are often used, even though they are less accurate, less reproducible for segmental analysis, and/or less prognostic. This project will develop cine DENSE into a method that retains high accuracy and reproducibility and is also fast and easy-to-use. To achieve this goal, we propose four specific aims. In Aim 1, we will develop an efficient self-navigated free-breathing cine DENSE method, and in Aim 2 we will develop accelerated cine DENSE using simultaneous multislice methods. The methods in Aims 1 and 2 will be combined to enable accelerated free-breathing imaging. In Aim 3, we will develop methods for fully automatic displacement and strain analysis, enabling the implementation of inline strain mapping. Finally, in Aim 4 we will validate the methods developed in Aims 1-3 in healthy volunteers and HF patients scheduled to undergo CRT. Altogether, this project will result in a fast, reproducible, convenient and well-validated myocardial strain imaging method that will be broadly useful for the field of cardiac imaging.