使用（噪声）惯性测量进行膝关节负重锥形束CT中的刚性和非刚性运动补偿
Rigid and non-rigid motion compensation in weight-bearing cone-beam CT of the knee using (noisy) inertial measurements
摘要：
受试者的不自主运动是膝关节负重锥形束CT中伪影的主要来源。为了获得用于临床诊断的图像质量，需要对运动进行补偿。我们建议使用惯性测量单元（IMU）连接到腿的运动估计。我们进行了模拟研究，使用真实的运动记录与光学跟踪系统。三个基于IMU的校正方法进行评估，即刚性运动校正，非刚性2D投影变形和非刚性3D动态重建。我们提出了一个初始化过程的基础上系统的几何形状。通过IMU噪声仿真，我们研究了所提出的方法在实际应用中的适用性。所有提出的基于IMU的方法至少与最先进的基于标记的方法一样好地校正运动。与未校正的情况相比，无运动和运动校正的体积之间的结构相似性指数和均方根均方误差分别提高了24-35%和78- 85%。噪声分析表明，市售IMU的噪声水平需要提高$10^5$的因子，这是目前仅通过专用硬件实现的，对于应用来说不够鲁棒。所提出的研究证实了这种新方法的可行性，并定义了一个真正的应用程序所需的改进。
英文摘要：
Involuntary subject motion is the main source of artifacts in weight-bearing cone-beam CT of the knee. To achieve image quality for clinical diagnosis, the motion needs to be compensated. We propose to use inertial measurement units (IMUs) attached to the leg for motion estimation. We perform a simulation study using real motion recorded with an optical tracking system. Three IMU-based correction approaches are evaluated, namely rigid motion correction, non-rigid 2D projection deformation and non-rigid 3D dynamic reconstruction. We present an initialization process based on the system geometry. With an IMU noise simulation, we investigate the applicability of the proposed methods in real applications. All proposed IMU-based approaches correct motion at least as good as a state-of-the-art marker-based approach. The structural similarity index and the root mean squared error between motion-free and motion corrected volumes are improved by 24-35% and 78-85%, respectively, compared with the uncorrected case. The noise analysis shows that the noise levels of commercially available IMUs need to be improved by a factor of $10^5$ which is currently only achieved by specialized hardware not robust enough for the application. The presented study confirms the feasibility of this novel approach and defines improvements necessary for a real application.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
