Real-Time MRI Motion Correction System

描述（由申请人提供）：动机-运动仍然是MR研究中图像伪影的最常见因素之一。 MRI的运动敏感性是众所周知的，并催生了许多优雅的导航技术。 然而，这些方法被定制为需要修改的k空间轨迹或采集附加MR数据的特定MR采集，并且大多数不能校正某些类型的运动，例如，通过平面运动。 此外，运动校正已经集中在特定系列的序列上，但是目前不存在普遍适用的方法。 某些患者人群，如儿科或老年患者，比其他患者更容易移动。 在儿科成像中，麻醉用于控制运动，大大增加了检查成本和患者风险。 序列独立、自主和前瞻性的运动校正系统可以极大地提高广泛的MR检查的图像质量。 特别是对于儿科成像，我们预计减少对麻醉的依赖，以控制患者的运动。 AIMS -我们将专注于三个独立的具体目标（并行进行，并在4年内完成），以及我们认为对于建立技术/科学价值至关重要的相应子目标，并证明我们的实时自适应运动校正方法的拟议研发工作的可行性。 具体而言，这些目标是：（1）开发和评估常规临床使用的线圈安装MR兼容跟踪设备;（2）将姿势跟踪集成到实时MRI中;（3）在志愿者和患者中验证我们的实时运动校正系统。 方法-在目标1中，我们将改进MR扫描仪内基于计算机视觉的姿势估计方法，并构建可用于临床常规检查的MR兼容线圈安装姿势跟踪器。 在目标2中，我们将专注于减少姿势变化发生与MR扫描仪对这些姿势变化做出反应之间的延迟，并构建用于MR脉冲序列开发的软件库，该软件库允许对所有MR脉冲序列实施实时运动校正。 在目标3中，我们将在60名志愿者（30名成人和30名儿童）和120名患者（80名成人和40名儿童）中对我们的系统进行全面评估。 意义-我们的技术的影响有几个方面。 首先，它将通过减少由于运动伪影而导致质量受损的MR图像的数量来改善患者护理。 特别是由于越来越多地依赖于磁共振图像作为主要的诊断手段，这将减少误诊的数量。 其次，这项技术将有助于通过大幅提高MRI扫描仪的效率来降低国家在成像方面的高额支出。 最后，它将通过减少重复序列的需要来改善患者舒适度，以及减少旨在保持患者静止的镇静的必要性。 总的来说，这项技术将在临床实践和基础科学研究中对MRI产生重大影响。 公共卫生相关性：在每年进行的4000万次MRI检查中，患者在MRI检查期间的运动可能导致图像质量严重下降，并降低大部分MRI检查的效率。 这不仅是越来越多的关注，由于人口老龄化及其相关的疾病，而且在儿童和病人谁只是太生病，以保持静止在exam. This建议的目的是建立一个光学跟踪系统和方法，以适应MRI脉冲序列的变化，在病人的姿势在真实的时间。 该项目利用了R21项目以前的工作，在该项目中成功构建了原型系统。 具体而言，目的是（i）对现有原型进行创新性改进，使系统适用于临床常规，（ii）修改光学跟踪系统，使其与多种MR序列兼容，以及（iii）进行临床评价。 我们的实时技术是一种独特的创新解决方案，将提高MRI图像质量，从而改善患者护理，并将解决医疗保健系统成像成本不断上升的负担。

DESCRIPTION (provided by applicant): MOTIVATION - Motion remains one of the most frequent contributors to image artifacts in MR studies. The motion susceptibility of MRI is well-known and has spawned a number of elegant navigation techniques. These methods, however, are tailored to specific MR acquisitions that require modified k-space trajectories or the acquisition of additional MR data, and most are unable to correct certain types of motion, for example, through-plane motion. Moreover, motion correction has been focused on specific families of sequences, but no generally applicable approach currently exists. Certain patient populations, such as pediatric or geriatric patients, are more likely to move than others. In pediatric imaging, anesthesia is used to control motion, adding substantially to exam costs and patient risks. A sequence-independent, autonomous and prospective motion correction system could greatly improve image quality for a wide spectrum of MR examinations. For pediatric imaging, in particular, we anticipate reduced reliance on anesthesia to control patient motion. AIMS - We will be focusing on three independent specific aims (carried out in parallel and completed within 4 years), with corresponding subaims that we believe are important for establishing the technical/scientific merit and to demonstrate the feasibility of the proposed R&D efforts for our real-time adaptive motion correction approach. Specifically, these aims are: (1) to develop and evaluate a coil-mounted MR-compatible tracking device for routine clinical use; (2) to integrate pose tracking into real-time MRI; and (3) to validate our real-time motion correction system in volunteers and patients. METHODS -In Aim 1 we will improve the methods for computer-vision-based pose estimation inside an MR scanner and build an MR-compatible coil-mounted pose tracker that can be used in clinical routine examinations. In Aim 2 we will focus on reducing the latency between pose changes happening and the MR scanner reacting to these pose changes, and on building a software library for the MR pulse sequence development that allows one to implement real-time motion correction into all MR pulse sequences. In Aim 3 we will perform a thorough evaluation of our system on 60 volunteers (30 adults and 30 children) and 120 patients (80 adults and 40 children). SIGNIFICANCE - The impact of our technology has several facets. First, it will improve patient care by reducing the number of MR images with compromised quality because of motion artifacts. Especially because of the increasing reliance on MR Images as a primary means of diagnosis, this will reduce the number of misdiagnoses. Secondly, this technology will help to lower the high national spending on imaging by dramatically improving the efficiency of MRI scanners. Finally, it will improve patient comfort by reducing the need for repeat sequences, as well as reduce the necessity of sedation aimed at keeping the patient still. Overall, this technology will have a significant impact on MRI both in clinical practice and basic science research. PUBLIC HEALTH RELEVANCE: Synopsis Patient motion during an MRI exam can result in major degradation of image quality and decreased efficiency in a large portion of the 40 million MRI procedures performed annually. This is not only of increasing concern due to the aging population and its associated diseases, but also in children and patients who are simply too sick to remain still during an exam. This proposal aims to build an optical tracking system and methods to adapt MRI pulse sequences to changes in patient pose in real time. The project leverages on previous work from an R21 project in which a prototype system was successfully built. Specifically, the aims are to (i) introduce innovative improvements to the existing prototype, making the system suitable for use in clinical routine, (ii) modify the optical tracking system to be compatible with multiple MR sequences, and (iii) perform clinical evaluation. Our real-time technique is a unique and innovative solution that will improve MRI image quality and thus patient care, and will address the escalating burden of imaging costs on the health care system.