Kinect-Based Correction of Overexposure Artifacts in Knee Imaging with C-Arm CT Systems.
Kinect-Based Correction of Overexposure Artifacts in Knee Imaging with C-Arm CT Systems.
复制标题
DOI：
10.1155/2016/2502486
复制
发表时间：
2016
影响因子：
7.6
通讯作者：
Riess C
中科院分区：
文献类型：
--
作者：
Rausch J;Maier A;Fahrig R;Choi JH;Hinshaw W;Schebesch F;Haase S;Wasza J;Hornegger J;Riess C
客观的。演示一种补偿膝盖 CT 扫描中过度曝光伪影的新方法，无需在患者身上附加任何支撑装置。 C 臂 CT 系统提供了对站立患者进行负重膝盖扫描的机会，以诊断骨关节炎等疾病。然而，一个严重的问题是探测器在靠近髌骨的区域过度曝光，这是普通技术无法解决的。方法。 Kinect 相机用于通过算法消除靠近膝盖表面的过度曝光伪影。通过从更可靠的投影数据推断吸收值来校正过度曝光的近表面膝盖区域。为了实现这一目标，我们开发了一种交叉校准程序，将表面点从 Kinect 坐标转换为 CT 体素坐标。结果。重建数据中两个膝盖模型的伪影均显着减少，并且大部分截断区域得到恢复。结论。结果强调了所提出方法的可行性。可以提高交叉校准过程的准确性，以进一步改善校正结果。意义。该校正方法可以扩展到多 Kinect 设置，以便在现实场景中使用。使用深度相机不需要事先扫描，并且可以对过度曝光伪影进行时间同步校正。为了实现这一目标，我们开发了一种交叉校准程序，将表面点从 Kinect 坐标转换为 CT 体素坐标。
Objective. To demonstrate a novel approach of compensating overexposure artifacts in CT scans of the knees without attaching any supporting appliances to the patient. C-Arm CT systems offer the opportunity to perform weight-bearing knee scans on standing patients to diagnose diseases like osteoarthritis. However, one serious issue is overexposure of the detector in regions close to the patella, which can not be tackled with common techniques. Methods. A Kinect camera is used to algorithmically remove overexposure artifacts close to the knee surface. Overexposed near-surface knee regions are corrected by extrapolating the absorption values from more reliable projection data. To achieve this, we develop a cross-calibration procedure to transform surface points from the Kinect to CT voxel coordinates. Results. Artifacts at both knee phantoms are reduced significantly in the reconstructed data and a major part of the truncated regions is restored. Conclusion. The results emphasize the feasibility of the proposed approach. The accuracy of the cross-calibration procedure can be increased to further improve correction results. Significance. The correction method can be extended to a multi-Kinect setup for use in real-world scenarios. Using depth cameras does not require prior scans and offers the possibility of a temporally synchronized correction of overexposure artifacts. To achieve this, we develop a cross-calibration procedure to transform surface points from the Kinect to CT voxel coordinates.