Zhang Wei, Oraiqat Ibrahim, Lei Hao, Carson Paul L, Ei Naqa Issam, Wang Xueding
Department of Biomedical Engineering, University of Michigan, USA.
Department of Radiation Oncology, University of Michigan, USA.
BME Front. 2020 May 26;2020:9853609. doi: 10.34133/2020/9853609. eCollection 2020.
. The goal is to increase the precision of radiation delivery during radiotherapy by tracking the movements of the tumor and other surrounding normal tissues due to respiratory and other body motions. . This work presents the recent advancement of X-ray-induced radiation acoustic imaging (xRAI) technology and the evaluation of its feasibility for real-time monitoring of geometric and morphological misalignments of the X-ray field with respect to the target tissue by combining xRAI with established ultrasound (US) imaging, thereby improving radiotherapy tumor eradication and limiting treatment side effects. . An integrated xRAI and B-mode US dual-modality system was established based on a clinic-ready research US platform. The performance of this dual-modality imaging system was evaluated via experiments on phantoms and ex and rabbit liver models. . This system can alternatively switch between the xRAI and the US modes, with spatial resolutions of 1.1 mm and 0.37 mm, respectively. 300 times signal averaging was required for xRAI to reach a satisfactory signal-to-noise ratio, and a frame rate of 1.1 Hz was achieved with a clinical linear accelerator. The US imaging frame rate was 22 Hz, which is sufficient for real-time monitoring of the displacement of the target due to internal body motion. . Our developed xRAI, in combination with US imaging, allows for mapping of the dose deposition in biological samples , in real-time, during radiotherapy. . The US-based image-guided radiotherapy system presented in this work holds great potential for personalized cancer treatment and better outcomes.
目标是通过跟踪肿瘤及其他周围正常组织因呼吸和身体其他运动而产生的移动，提高放射治疗期间辐射传递的精度。这项工作展示了X射线诱导辐射声成像（xRAI）技术的最新进展，并通过将xRAI与成熟的超声（US）成像相结合，评估其对X射线场相对于靶组织的几何和形态错位进行实时监测的可行性，从而提高放射治疗对肿瘤的根除效果并限制治疗副作用。基于临床可用的研究型超声平台建立了集成xRAI和B模式超声的双模态系统。通过在体模以及离体和兔肝模型上进行实验，对该双模态成像系统的性能进行了评估。该系统可以在xRAI和US模式之间切换，空间分辨率分别为1.1毫米和0.37毫米。xRAI需要300次信号平均才能达到令人满意的信噪比，使用临床直线加速器可实现1.1赫兹的帧率。US成像帧率为22赫兹，足以实时监测由于身体内部运动导致的靶标位移。我们开发的xRAI与US成像相结合，能够在放射治疗期间实时绘制生物样本中的剂量沉积图。这项工作中提出的基于US的图像引导放射治疗系统在个性化癌症治疗和更好的治疗效果方面具有巨大潜力。
