Free-breathing and simultaneous multislice cine DENSE myocardial strain imaging

项目摘要 近10年来，心肌应变显像的应用和价值不断增加。之间 许多应用中，最突出的包括（a）评估癌症患者的心脏毒性， 化疗，（B）主动脉瓣狭窄的预后和危险分层，和（c）主动脉瓣狭窄的诊断和预后。 未分化左心室肥大我们已经开发了具有刺激的电影位移编码， Echoes（DENSE）应变MRI，与其他研究中心共享该方法，并将其应用于患者选择和手术 指导心力衰竭（HF）的心脏起搏治疗（CRT）。Cine DENSE具有高度准确性， 由于其可重复用于整体和节段性心肌应变的量化，因此正成为金标准 技术，并正在实施的主要制造商。然而，当前的电影DENSE成像需要 多次屏气采集或使用横膈膜的低效和不方便的自由呼吸采集， 基于导航器，这两种方法都不适合快速有效的多参数心脏MRI 协议或用于难以使用基于屏气的协议的患病患者。此外，内联应变分析是 不可用，因此该任务在工作站上离线执行。有了这些限制，更方便 经常使用诸如特征跟踪之类的方法，即使它们不太准确， 节段性分析和/或预后较差。该项目将发展电影密度成为一种方法， 准确性和可重复性，并且快速且易于使用。为实现这一目标，我们提出四项具体措施。 目标。在目标1中，我们将开发一种有效的自导航自由呼吸电影DENSE方法，在目标2中，我们 将使用同步多层方法开发加速电影DENSE。目标1和2中的方法将 以实现加速的自由呼吸成像。在目标3中，我们将开发全自动 位移和应变分析，实现内联应变映射。最后，在目标4中， 在健康志愿者和计划接受CRT的HF患者中验证目标1-3中开发的方法。 总之，本项目将导致一个快速，可重复性，方便和良好的验证心肌应变成像 该方法将广泛用于心脏成像领域。

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.