Arumugam Sankar, Sidhom Mark, Truant Daniel, Xing Aitang, Udovitch Mark, Holloway Lois
Department of Medical Physics, Liverpool and Macarthur Cancer Therapy Centres and Ingham Institute, New South Wales, Australia; South Western Clinical School, University of New South Wales, Sydney, New South Wales, Australia.
Department of Radiation Oncology, Liverpool and Macarthur Cancer Therapy Centres, New South Wales, Australia.
Phys Med. 2017 Jan;33:170-178. doi: 10.1016/j.ejmp.2016.12.014. Epub 2017 Jan 7.
To develop and validate a variable angle stereo image based position correction methodology in an X-ray based in-house online position monitoring system.
A stereo imaging module that enables 3D position determination and couch correction of the patient based on images acquired at any arbitrary angle and arbitrary angular separation was developed and incorporated to the in-house SeedTracker real-time position monitoring system. The accuracy of the developed system was studied by imaging an anthropomorphic phantom implanted with radiopaque markers set to known offset positions from its reference position in an Elekta linear accelerator (LA) and associated XVI imaging system. The accuracy of the system was further validated using CBCT data set from 10 prostate SBRT patients. The time gains achieved with the stereo image based position correction was compared with the manual matching of seed positions in Digitally Reconstructed Radiographs (DRRs) and kV images in the Mosaiq record and verify system.
Based on phantom and patient CBCT dataset study stereo imaging module implemented in the SeedTracker shown to have an accuracy of 0.1(σ=0.5)mm in detecting the 3D position offset. The time comparison study showed that stereo image based methodology implemented in SeedTracker was a minimum of 80(4)s faster than the manual method implemented in Mosaiq R&V system with a maximum time saving of 146(6)s.
The variable angle stereo image based position correction method was shown to be accurate and faster than the standard manual DRR-kV image based correction approach, leading to more efficient treatment.
在基于X射线的内部在线位置监测系统中开发并验证一种基于可变角度立体图像的位置校正方法。
开发了一种立体成像模块，该模块能够根据在任意角度和任意角间距获取的图像确定患者的三维位置并进行治疗床校正，并将其整合到内部的SeedTracker实时位置监测系统中。通过对一个植入了不透射线标记物的人体模型进行成像来研究开发系统的准确性，该人体模型在医科达直线加速器（LA）和相关的XVI成像系统中设置为相对于其参考位置有已知的偏移位置。使用来自10例前列腺SBRT患者的CBCT数据集进一步验证该系统的准确性。将基于立体图像的位置校正所实现的时间增益与在Mosaiq记录和验证系统中数字重建射线照片（DRR）和kV图像中种子位置的手动匹配进行比较。
基于人体模型和患者CBCT数据集的研究表明，SeedTracker中实现的立体成像模块在检测三维位置偏移时的精度为0.1（σ=0.5）mm。时间比较研究表明，SeedTracker中实现的基于立体图像的方法比Mosaiq R&V系统中实现的手动方法至少快80（4）秒，最大节省时间为146（6）秒。
基于可变角度立体图像的位置校正方法被证明是准确的，并且比基于标准手动DRR-kV图像的校正方法更快，从而实现了更高效的治疗。
