Nofiele Joris, Yuan Qing, Kazem Mohammad, Tatebe Ken, Torres Quinn, Sawant Amit, Pedrosa Ivan, Chopra Rajiv
Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA.
Sunnybrook Research Institute, Toronto, Ontario, Canada.
Magn Reson Med. 2016 Aug;76(2):702-12. doi: 10.1002/mrm.25903. Epub 2015 Oct 23.
Abdominal MRI remains challenging because of respiratory motion. Motion compensation strategies are difficult to compare clinically because of the variability across human subjects. The goal of this study was to evaluate a programmable system for one-dimensional motion management MRI research.
A system comprised of a programmable motorized linear stage and computer was assembled and tested in the MRI environment. Tests of the mutual interference between the platform and a whole-body MRI were performed. Organ trajectories generated from a high-temporal resolution scan of a healthy volunteer were used in phantom tests to evaluate the effects of motion on image quality and quantitative MRI measurements.
No interference between the motion platform and the MRI was observed, and reliable motion could be produced across a wide range of imaging conditions. Motion-related artifacts commensurate with motion amplitude, frequency, and waveform were observed. T2 measurement of a kidney lesion in an abdominal phantom showed that its value decreased by 67% with physiologic motion, but could be partially recovered with navigator-based motion-compensation.
The motion platform can produce reliable linear motion within a whole-body MRI. The system can serve as a foundation for a research platform to investigate and develop motion management approaches for MRI. Magn Reson Med 76:702-712, 2016. © 2015 Wiley Periodicals, Inc.
由于呼吸运动,腹部磁共振成像(MRI)仍然具有挑战性。由于不同人体受试者之间存在变异性,运动补偿策略在临床上难以比较。本研究的目的是评估一种用于一维运动管理MRI研究的可编程系统。
组装了一个由可编程电动线性平台和计算机组成的系统,并在MRI环境中进行测试。进行了平台与全身MRI之间相互干扰的测试。在体模测试中使用从健康志愿者的高时间分辨率扫描生成的器官轨迹,以评估运动对图像质量和定量MRI测量的影响。
未观察到运动平台与MRI之间的干扰,并且在广泛的成像条件下可以产生可靠的运动。观察到与运动幅度、频率和波形相称的运动相关伪影。腹部体模中肾脏病变的T2测量显示,在生理运动下其值下降了67%,但通过基于导航器的运动补偿可以部分恢复。
运动平台可以在全身MRI内产生可靠的线性运动。该系统可以作为一个研究平台的基础,用于研究和开发MRI的运动管理方法。《磁共振医学》76:702 - 712, 2016。© 2015威利期刊公司。