Abstract
Purpose:The difference between three‐dimensional (3D) and four‐dimensional (4D) dose is affected by factors such as tumor size and motion. To quantitatively analyze the effects of these factors, a phantom that can independently control for each factor is required. The purpose of this study is to develop a deformable lung phantom with the above attributes and evaluate characteristics.Methods:A phantom was designed to simulate diaphragm motion with amplitude in the range 1 to 7 cm and various periods of regular breathing. To simulate different size tumors, tumors were produced by pouring liquid silicone into custom molds created by a 3D printer. The accuracy of phantom diaphragm motion was assessed using calipers and protractor. To control tumor motion, tumor trajectories were evaluated using 4D computed tomography (CT), and diaphragm‐tumor correlation curve was calculated by curve fitting method. Three‐dimensional dose and 4D dose were calculated and compared according to tumor motion.Results:The accuracy of phantom diaphragm motion was less than 1 mm. Maximum tumor motion amplitudes in the left‐right and anterior‐posterior directions were 0.08 and 0.12 cm, respectively, in a 10 cm3 tumor, and 0.06 and 0.27 cm, respectively, in a 90 cm3 tumor. The diaphragm‐tumor correlation curve showed that tumor motion in the superior‐inferior direction was increased with increasing diaphragm motion. In the 10 cm3 tumor, the tumor motion was larger than the 90 cm3 tumor. According to tumor motion, variation of dose difference between 3D and 4D was identified.Conclusion:The developed phantom can independently control factors such as tumor size and motion. In potentially, this phantom can be used to quantitatively analyze the dosimetric impact of respiratory motion according to the factors that influence the difference between 3D and 4D dose.This research was supported by the Mid‐career Researcher Program through NRF funded by the Ministry of Science, ICT & Future Planning of Korea (NRF‐2014R1A2A1A10050270) and by the Radiation Technology R&D program through the National Research Foundation of Korea funded by the Ministry of Science, ICT & Future Planning (No. 2013M2A2A7038291)
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
