Feasibility study on the application of accelerator MV CBCT images in adaptive radiation therapy
10.3760/cma.j.issn.0254-5098.2017.05.007
- VernacularTitle:加速器MV CBCT扫描图像在自适应放疗中应用的可行性研究
- Author:
Tingtian PANG
;
Bo YANG
;
Xia LIU
;
Nan LIU
;
Tingting DONG
;
Jie QIU
- Keywords:
Adaptive radiation therapy;
Megavoltage cone beam CT;
Image value to density table (IVDT);
Dose distribution
- From:
Chinese Journal of Radiological Medicine and Protection
2017;37(5):359-362
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate whether the accelerator image beam line (IBL) full scan and extend field of view(EFOV) scan mode megavoltage cone beam CT(MV CBCT) images can be used for dose calculation in adaptive radiotherapy.Methods The large aperture CT and MV CBCT were used to scan the CIRS 062M electron density modules,the CT value was established to electron density curves in the Pinnacle treatment planning system.Also,CT and MV CBCT were used to scan the head and neck,chest,abdomen and pelvis phantom.The intensity modulated radiotherapy(IMRT) plans were made with CT images and transplanted to MV CBCT images.The dose of targets and organs with their electron density curves was calculated,and two type IMRT plans with different CT images were compared.Results The dose distribution of head and neck phantom was acceptable,compared with the reference plan,the difference was within 3 ％.The dose distribution of chest and.pelvis was significantly reduced from reference plans,and the difference was 5％ and 10％ separately.This difference was beyond the scope of clinical acceptance.Conclusions MV CBCT images of accelerator IBL full scan mode in patients with head and neck site scan could be used for dose calculation in adaptive radiotherapy,chest and pelvic sites in EFOV mode scanning MV CBCT images could only be used for image guidance.
