Dose accumulation of volumetric modulated arc radiation therapy for prostate cancer using deformable image registration
1
Issued Date
2024
Copyright Date
2019
Resource Type
Language
eng
File Type
application/pdf
No. of Pages/File Size
xiv, 123 leaves : ill.
Access Rights
open access
Rights
ผลงานนี้เป็นลิขสิทธิ์ของมหาวิทยาลัยมหิดล ขอสงวนไว้สำหรับเพื่อการศึกษาเท่านั้น ต้องอ้างอิงแหล่งที่มา ห้ามดัดแปลงเนื้อหา และห้ามนำไปใช้เพื่อการค้า
Rights Holder(s)
Mahidol University
Bibliographic Citation
Thesis (M.Sc. (Radiological Technology))--Mahidol University, 2019
Suggested Citation
Achawee Suwannarat Dose accumulation of volumetric modulated arc radiation therapy for prostate cancer using deformable image registration. Thesis (M.Sc. (Radiological Technology))--Mahidol University, 2019. Retrieved from: https://repository.li.mahidol.ac.th/handle/123456789/92180
Title
Dose accumulation of volumetric modulated arc radiation therapy for prostate cancer using deformable image registration
Author(s)
Abstract
Cone-beam computed tomography (CBCT) is typically aimed for pre-treatment setup verification to ensure treatment accuracy. However, their three-dimensional anatomical information of the patient on the treatment day has also showed the potential for adaptive radiation therapy and as to be the dose monitoring system. The aim of this work is to study the proper procedure of using CBCT images and Velocity AI 3.2.0 deformable image registration (DIR) software in predicting the accumulated dose for conventional fraction VMAT prostate cancer patients and to investigate and verify the accuracy of DIR software. The CBCT image quality was firstly evaluated using Catphan 600 phantom underwent on-board imaging (OBI). Then, the accuracy of DIR using Velocity AI 3.2.0 software was evaluated. The CBCT HU to electron density calibration curve was generated using CIRS CBCT electron density phantom-062A. Then, the accuracy of planning CT (PCT)-based dose calculation (DPCT), CBCT-based dose calculation (DCBCT) and dose deformation from PCT to CBCT image using DIR property was verified by comparing with dose measurements using IC (0.13cc) and Gafchromic EBT3 film on CIRS pelvic phantom model 002PRA. In clinical investigation, planning target volume (PTV) and organ at risks (OARs) were deformed from PCT to fractionated CBCT by Velocity AI 3.2.0 DIR software and modified by radiation oncologist. Dose distribution in each CBCT fraction was generated using CBCT HU to electron density calibration curve and calculated on EclipseTM treatment planning system 13.6.0. Dose in every fractionated CBCT was deformed, summed and mapped on PCT. The variation of the organ volume as well as the dosimetric parameters following the QUANTEC-guideline for PTV and OARs were collected and analyzed. The results showed the CBCT image quality and the accuracy of DIR using DIR protocol which was implemented in Velocity AI software were in the acceptable level of AAPM TG No. 179 and 132, respectively. Point dose differences in phantom between the measurements and DPCT, DCBCT, and dose deform were 2.03%, 2.28% and 2.73%, respectively. DPCT, DCBCT and dose deform compared with the measurement dose for dose distribution were 91.23%, 87.7% and 85.40% when considering at the (3%/3mm) gamma passing rate. In clinical investigation, the volume ratios of CBCT/PCT for PTV, bladder and rectum were found to be 1.02, 0.92 and 0.94. The dose differences of predicted accumulation dose using CBCT dose calculation and planning dose were -4.24 Gy for D95% of PTV, -1.32 Gy and -4.80 cc for Dmean and V70Gy of bladder, and -1.37 Gy, and -1.74 cc for Dmean and V70Gy of rectum, respectively. In conclusion, the accumulation dose using CBCT image and DIR to guide organ contouring is found to be feasible and adequate to predict the actual dose delivery to the VMAT prostate cancer
Description
Radiological Technology (Mahidol University 2019)
Degree Name
Master of Science
Degree Level
Master's degree
Degree Department
Faculty of Medical Technology
Degree Discipline
Radiological Technology
Degree Grantor(s)
Mahidol University