摘要
目的建立利用3D打印颅脑辐射等效体模对患者进行个性化放疗剂量验证的方法，为三维适形放射治疗安全提供一种可靠的剂量保证手段。方法采集两例患者（患者1和患者2）的CT图像数据，基于患者1的图像数据，重建其颅骨与脑组织，制作颅脑体模，验证颅骨与脑组织的等效材料。基于患者2的图像数据，根据3D图像重建并选用组织等效材料重建完全的头颅结构，采用3D打印技术制作全头颅体模。通过对目标区域插入电离室剂量仪并行放射治疗方案，获得头颅体模病灶部的剂量，验证和校准实际放疗计划的安全性。结果对所获两个体模分别进行DR、CT成像，颅脑体模的等效骨骼与患者1骨骼的x射线灰度值差异为13721，颅脑体模的等效脑组织与患者1的脑组织的CT值差异为35～40HU，全头颅体模等效颞肌与患者2的颞肌组织的CT值差异为18～28HU，影像数据表明体模材质的辐射等效性与人体组织近似，并且等效剂量分布符合常规治疗范围，体模的剂量验证可以有效验证放疗计划系统的准确性。结论基于3D打印和组织等效技术所设计的个性化放疗体模，可应用于个性化放射治疗验证。体模制作方法简单快速，个性化程度高，为三维适形放射治疗安全提供一种可靠的剂量保证手段。
Objective To establish a on 3D printing radiology equivalent phantom method-based for individual radiotherapy dose verification, and to offer an assurance for the safety of 3D conformal radiotherapy. Methods Two patients＇ CT data was collected, reconstructing the first patient＇s skull and brain tissue to generate a skull-brain phantom for the purpose of testing the equivalent material. The second patient＇s data was used for whole head tissue reconstruction to produce a head phantom with equivalent material. By inserting ionization chamber dosimeters to target region for radiotherapy program, equivalent phantom dose distribution of lesions location was obtained in order to verify and calibrate the actual radiation treatment planning for patients. Results DR, CT images of the phantoms revealed that the difference of X-ray gray value between brain skull phantom and patient＇s skull was 13 721, CT value difference between equivalent tissue of brain skull phantom and that part of the patient was 35 -40 HU, and CT difference between head phantom temporalis and that of the patient tissue was 18- 28 HU. The imaging data indicated that the radiation equivalence of 3D printing phantom was similar to that of human body tissue, and the equivalent dose distribution accorded well with the normal range of treatment. The dose verification of phantom model can effectively improve the accuracy of the radiotherapy system. Conclusions The personalized radiotherapy phantom which based on the 3D printing and tissue equivalent technology is suitable for personalized radiation therapy validalion. With advantages of easy accessibility, highly-personalized degree and high preeision, this technology provides a reliable and safe way for radiation therapy.
出处
《中华放射医学与防护杂志》
CAS
CSCD
北大核心
2017年第6期437-441,共5页
Chinese Journal of Radiological Medicine and Protection
基金
国家重点研发计划项目（2016YFC0103400）
关键词
3D打印
体模
放射治疗
剂量验证
3D printing
Phantom
Radiotherapy
Dose verification
