用于肺癌精准放疗的高分辨移动条带CT影像引导关键技术基础研究

影像引导放射治疗（IGRT）代表了当今放疗发展的趋势，但是，其经过十余年的应用并未在实质上提高肿瘤治疗收益，主要原因是现有IGRT技术“看得不够清、打得不够准”，即未能获取高分辨的在线影像，从而无法在线调整放疗计划，导致肿瘤漏照和正常器官的误照。特别是肺癌，由呼吸运动带来的运动伪影和位置不确定性导致现有IGRT技术已无法满足精准放疗的要求。就此科学问题，在前期C型臂CT成像和呼吸监控系统研究工作的基础上，我们提出一种高分辨移动条带CT（Moving Band CT，MBCT）成像方式，融合锥形束CT开放式结构和扇形束CT抑制散射的优点，从空间、密度和时间分辨率上提高IGRT图像质量，并使该图像能够支持准确的剂量计算，从而建立基于先验信息的在线放疗计划优化方法，实现计划在线调整，使IGRT可以“看得清、打得准”，从成像和计划优化两个关键技术上改变现有不足，提高放疗准确性，为患者带来更大收益。

Image guided radiotherapy (IGRT) stands for the developing trend of radiation oncology nowadays. However, after the application of IGRT for more than ten years, it doesn’t improve the overall outcome at cancer treatment. The main reason is that the current IGRT technique can neither get high resolution on line images nor deliver the dose accurately by adjusting the treatment plan before each fraction, therefore, the treatment may miss the tumor while bring more complications. Especially for the lung cancer, the motion artifact and the position uncertainty make the current IGRT technique unsatisfied to accurate radiotherapy. Considering this scitifict issue, based on our previous achievements, a high resolution moving band CT (MBCT) imaging method is proposed. MBCT have open architecture like cone-bema CT (CBCT) and the advantagement of denoising like fan-beam CT as well. It will improve the IGRT image quality, enable the accurate irridation dose calculation and on-line plan optimization algorithms. This technique will bring IGRT clear images and accurate dose delivery, which will cover the current shortage of IGRT and bring more benefit to the patients.