Heavy ion therapy is currently recognized as the most advanced cancer radiotherapy approach in the world. This article introduces a high-precision and non-contact measurement method based on close-range photogrammetry combined with a 3D control network of a laser tracker, which is used to guide the positioning and real-time target area monitoring for patients undergoing heavy ion radiotherapy. By the precise connection between the 3D control network of the laser tracker and the digital photogrammetry device, we position the photogrammetry system absolutely at the treatment isocenter, measuring the feature points of the target area on the patient's body surface. After that, the seven-parameter solution model is combined with the feature points to accurately determine the tumor position, as well as displaying its real-time location changes in the form of relative position to the treatment isocenter shown as six-degree-of-freedom parameters during radiotherapy, so that the patient may be guided to achieve a more reliable and efficient positioning. The research and design on the dual-camera close-range photogrammetry patient monitoring system has provided insights in the course of radiotherapy. That is to say, by monitoring the feature points on the patient's body surface, a real-time display of tumor displacement and a warning system for out-of-tolerance variances are established, controlling the treatment bed to stay on the tumor. This method could ensure the irradiation precision for the patient during the treatment and protect normal tissues from radiation exposure, optimizing the treatment outcome. Multiple patient positioning simulations have verified that the measurement precision of our photogrammetry-based method can meet the requirements of heavy ion radiotherapy patient positioning.

重离子治疗是目前公认的世界上最先进的癌症放射治疗方法。本文介绍了一种基于近距离摄影测量结合激光跟踪仪3D控制网络的高精度非接触测量方法，用于指导重离子放疗患者的定位和实时目标区域监测。 . 通过激光跟踪仪的3D控制网络与数字摄影测量设备的精确连接，我们将摄影测量系统绝对定位在治疗等中心点，测量患者体表目标区域的特征点。之后，七参数解模型结合特征点准确确定肿瘤位置，并在放疗过程中以六自由度参数显示其相对于治疗等中心点的相对位置变化的实时位置变化，从而引导患者实现更可靠、更高效的定位。双摄像头近距离摄影测量病人监护系统的研究和设计为放疗过程提供了启示。也就是说，通过监测患者体表的特征点，实时显示肿瘤位移和超差偏差预警系统，控制治疗床停留在肿瘤上。该方法可以保证患者在治疗过程中的照射精度，保护正常组织免受辐射照射，优化治疗效果。