Adaptive 4D MR Imaging using navigator-based respiratory signal for MRI-Guided therapy
Adaptive 4D MR Imaging using navigator-based respiratory signal for MRI-Guided therapy
复制标题
DOI：
10.1002/mrm.21436
复制
发表时间：
2008-05-01
影响因子：
3.3
通讯作者：
Dohi, Takeyoshi
中科院分区：
文献类型：
--
作者：
Tokuda, Junichi;Morikawa, Shigehiro;Dohi, Takeyoshi
为了实现 MRI 引导治疗中呼吸器官运动的实时 3D 可视化，开发了一种基于导航回波和多个选通窗口的新型自适应 4D MR 成像方法。该方法旨在获取循环运动器官的时间序列体积 3D 图像，从而能够通过实时同步 4D 图像与实际器官运动来指导治疗。所提出的方法在开放配置的 0.5T 临床 MR 扫描仪中实施。为了评估可行性并确定最佳成像条件，对模型、志愿者和患者进行了研究。在体模研究中，循环移动体模的 4D 图像中的均方根 (RMS) 位置误差为 1.9 毫米，当 4D 图像有六帧时，成像时间约为 10 分钟。在患者研究中，在临床条件下成功获取了 4D 图像，并在一系列帧中区分出肝脏肿瘤。图像质量受到编码方向、切片方向和目标器官运动方向之间关系的影响。总之，本研究表明所提出的方法是可行的，并且能够为手术导航提供具有足够精度和图像质量的实时动态3D图集。
For real-time 3D visualization of respiratory organ motion for MRI-guided therapy, a new adaptive 4D MR imaging method based on navigator echo and multiple gating windows was developed. This method was designed to acquire a time series of volumetric 3D images of a cyclically moving organ, enabling therapy to be guided by synchronizing the 4D image with the actual organ motion in real time. The proposed method was implemented in an open-configuration 0.5T clinical MR scanner. To evaluate the feasibility and determine optimal imaging conditions, studies were conducted with a phantom, volunteers, and a patient. In the phantom study the root mean square (RMS) position error in the 4D image of the cyclically moving phantom was 1.9 mm and the imaging time was approximate to 10 min when the 4D image had six frames. In the patient study, 4D images were successfully acquired under clinical conditions and a liver tumor was discriminated in the series of frames. The image quality was affected by the relations among the encoding direction, the slice orientation, and the direction of motion of the target organ. In conclusion, this study has shown that the proposed method is feasible and capable of providing a real-time dynamic 3D atlas for surgical navigation with sufficient accuracy and image quality.