被动呼吸门控下腹部肿瘤的剂量反馈自适应放疗技术研究

项目名称： 被动呼吸门控下腹部肿瘤的剂量反馈自适应放疗技术研究

项目编号： No.11205033

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 物理学II

项目作者： 胡伟刚

作者单位： 复旦大学

项目金额： 28万元

中文摘要： 腹部肿瘤如胃、肝癌是我国的高发肿瘤。腹部肿瘤的放射治疗已被证实可提高局部控制率,与其他肿瘤相比，腹部肿瘤周围正常组织剂量耐受低，且呼吸运动和器官移动皆可影响每次治疗时靶区的确定性，导致实际治疗的剂量分布与计划的不一致，因此迫切需要综合多种物理技术以减少运动和形变的影响；同时需要建立实时的空间几何和剂量验证及反馈技术模型，来保证分次治疗间治疗实施的准确性。本课题在前期研究中，改进和综合了现有的门控技术，并研发一项被动呼吸控制设备，计划在本研究中结合容积弧形调强技术来实现被动呼吸控制下的腹部肿瘤放疗，实现最优化正常组织保护的同时最大限度的减少治疗时间。同时研究出被动呼吸控制下三维锥形束CT影像的采集和重建，建立分次放疗基于锥形束CT影像的剂量分布验证及利用分次剂量分布进行在线或离线剂量反馈修正的临床模型，研究出被动呼吸门控下基于剂量反馈的自适应放疗技术，为未来疗效引导的个体化放射治疗奠定基础。

中文关键词： 放射治疗；呼吸控制；影像引导；容积调强；锥形束CT

英文摘要： The abdominal cancers, such as gatric and liver cancers, have high incidences in China. It has been confirmed that the radiotherapy can improve their local controls ,however,the abdominal cancer radiation has its special features compared with other sites cancer because of its low surrounding normal tissue tolerance and its suspectible to intra-fractional respiratory motions and inter-fractional organ deformations. All these effects can lead to the variation between the actually delivered dose and planned dose. Therefore,it is crucial to reduce the repiration motions by integrating reasonable techniques and using advance algorithms to optimize the treatment plans for better target coverage and normal tissue sparing; meanwhile, the online or offline geometric and dosimetric verfication model should be established to study the intrafractional dose varies and ensure the accuracy of the treatment delivery. This study will develop a new treatment strategy of combining a homemade passive breath control device, a commercial realtime position management (RPM) system, and the volumetric modulated arc therapy (VMAT) for passive breath hold radiotherapy in the pelvic cance. Compared to the current techniques, the new treatment strategy has the advantages of less treatment delivery time and better normal tissues sparing. B

英文关键词： radiation therapy；breath control；image guidance；volumetric modulation arc therapy；cone beam CT