Quantitative Analysis of Carpal Kinematics Using 3D Dynamic MRI

项目概要/摘要 手腕是一个复杂而多功能的结构，它允许相当程度的三维运动。 为了充分诊断和治疗腕关节损伤，重要的是要了解基础科学和临床 腕关节功能运动学的相关性。然而，腕骨运动学的分析是具有挑战性的， 腕骨的多平面旋转和平移，其形状的不规则性，以及小的 运动的幅度。大多数研究都是在体外和体内对尸体手腕进行的 最近才提出了基于非侵入性成像的方法。初始体内工作使用CT或 MRI以获得手部多个静态姿势下腕骨的三维（3D）图像，以进行重建 一种生动的运动模式。由于真实的动态关节运动学可能偏离其动画对应物， 最近的工作已经探索了使用4DCT在连续手腕运动期间实时成像的可能性， 荧光透视和二维（2D）动态MRI。然而，这些方法要么涉及电离辐射， 或者不能捕获即使在相对简单的腕关节运动期间也发生的平面外平移和旋转 因为它们的2D特性。在这个项目中，我们将开发一种新的定量分析技术 腕关节运动学的基础上，第一次，在三维动态磁共振成像采集。我们将开发一种处理 将联合收割机自动分割腕骨和提取其运动模式相结合的流水线 在腕部的尺桡偏斜和屈伸期间。我们会进行一项试验性研究， 具有腕关节不稳定临床证据的志愿者和患者，目的是表征正常腕关节 运动学和识别定量度量以检测病理性腕部状况。我们还将调查 基于并行MRI和压缩感知的组合的替代成像方法， 加速3D动态MRI。在项目结束时，我们将验证这种新的动态成像 一种技术，以评估改善的时间分辨率是否对腕骨分析具有临床意义 运动学该项目的成功完成将提供一种新的，基于3D MRI的体内技术， 3D骨骼运动学的表征和可视化，为正常腕关节功能提供新的见解 和腕关节不稳定的病理生理学。我们提出的自动化图像处理管道将有助于临床 翻译.评估动态运动模式的能力将有助于诊断、治疗和修复 开发用于腕关节疾病的治疗工具，从而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价产生影响 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.