Quantitative Analysis of Carpal Kinematics Using 3D Dynamic MRI

项目摘要/摘要 手腕是一种复杂而多才多艺的结构，它允许相当程度的三维运动。 为了更好地诊断和治疗腕部损伤，了解基础科学和临床是重要的。 腕关节功能运动学的相关性。然而，腕部运动学的分析是具有挑战性的，因为 腕骨的多平面旋转和平移，其形状的不规则性，以及小的 运动的大小。大多数研究都是在身体手腕上进行的，在体内也是如此。 基于非侵入性成像的方法直到最近才被提出。最初的活体工作使用CT或 磁共振成像获取手部多个静态姿势下的腕骨三维(3D)图像以进行重建 一种生动的运动模式。由于真正的动态关节运动学可能会偏离其动画对应物， 最近的工作探索了使用4D CT在连续腕部运动期间进行实时成像的可能性， 透视和二维(2D)动态磁共振成像。然而，这些方法要么涉及电离辐射 或者不能捕捉即使在相对简单的手腕上也会发生的平面外平移和旋转 运动，因为它们的2D性质。在这个项目中，我们将开发一种新的定量分析技术 首次基于3D动态MRI采集的腕部运动学研究。我们将开发一种处理 将结合自动分割腕骨和提取其运动模式的流水线 在尺骨偏斜和腕关节屈伸的过程中。我们将进行一项关于健康的先导验证研究 志愿者和有腕关节不稳定临床证据的患者，目的是描述正常腕关节的特征 运动学和识别定量指标，以检测病理手腕状况。我们还将调查一名 基于并行MRI和压缩感知相结合的替代成像方法 加速三维动态核磁共振成像。在项目接近尾声时，我们将验证这种新的动态成像 评估改进的时间分辨率对于腕骨分析是否具有临床意义的技术 运动学。该项目的成功完成将为活体研究提供一种新的基于3D MRI的技术 3D骨骼运动学的表征和可视化，提供了对正常腕部功能的新见解 以及腕关节不稳定的病理生理学。我们建议的自动图像处理流水线将有助于临床 翻译。评估动态运动模式的能力将有助于诊断、治疗和假体修复 手腕疾病的发展，使之能够评估愈合和手术干预的长期效果。 所提出的技术也可能对其他解剖结构的动态评估产生影响 例如脚踝。

Project Summary/Abstract The wrist is a complex and versatile structure, which allows a substantial degree of three-dimensional motion. To adequately diagnose and treat carpal injuries, it is important to understand the basic science and clinical relevance of functional kinematics of the wrist. However, the analysis of carpal kinematics is challenging due to the multiplanar rotations and translations of the carpal bones, the irregularity of their shape, and the small magnitudes of movements. Most studies have been performed in vitro on cadaveric wrists, and in vivo approaches based on noninvasive imaging have been proposed only recently. Initial in vivo work used CT or MRI to obtain three-dimensional (3D) images of carpal bones at multiple static poses of the hand to reconstruct an animated movement pattern. Since true dynamic joint kinematics may deviate from its animated counterpart, more recent work has explored the possibility of real-time imaging during continuous wrist motion using 4D CT, fluoroscopy and two-dimensional (2D) dynamic MRI. However, these methods either involves ionizing radiation or cannot capture out-of-plane translations and rotations that occur even during relatively simple wrist movements, because of their 2D nature. In this project, we will develop a new technique for quantitative analysis of carpal kinematics based, for the first time, on 3D dynamic MRI acquisitions. We will develop a processing pipeline that will combine automated segmentation of the carpal bones and the extraction of their motion patterns during ulnar-radial deviation and flexion-extension of the wrist. We will conduct a pilot validation study on healthy volunteers and patients with clinical evidence of carpal instability, with the goal of characterizing normal wrist kinematics and identifying quantitative metrics to detect pathologic wrist conditions. We will also investigate an alternative imaging approach based on the combination of parallel MRI and compressed sensing to further accelerate the 3D dynamic MRI. Toward the end of the project, we will validate this new dynamic imaging technique to assess whether the improved temporal resolution is clinically significant for the analysis of carpal kinematics. Successful completion of this project will provide a new, 3D MRI-based technique for in vivo characterization and visualization of 3D skeletal kinematics, providing novel insights into normal wrist function and pathophysiology of wrist instability. Our proposed automated image processing pipeline will facilitate clinical translation. The ability to assess dynamic motion patterns will contribute to diagnosis, therapy, and prosthesis development for wrist disorders, enabling to evaluate the long-term effects of healing and surgical intervention. The proposed technique could also have an impact for the dynamic evaluation of other anatomical structures such as, for example, the ankle.