Dosimetry influence of different radiotherapy technologies caused by cavity and inhomogeneous tissues

VernacularTitle:空腔和非均匀组织对不同照射技术的剂量学影响
Author: Jian LI ; Shengwei KANG ; Guohai QI ; Dake WU ; Hailuo ZHONG ; Pei WANG
Publication Type:Journal Article
Keywords: Chengdudosimetric phantoms; Cavity; Inhomogeneous tissue; Thermoluminescence
From: Chinese Journal of Radiation Oncology 2014;23(5):437-440
CountryChina
Language:Chinese
Abstract: Objective To investigate influence on dose distribution due to cavity and inhomogeneous structures using thermoluminescence dosimeters (TLD) and Chengdu phantoms.Methods A cavity 4 cm × 4 cm × 3 cm was made by a head and neck phantom and a lung phantom was cut into slices which were got a CT scanning and setup in a digital simulator.The TLD were pasted on edge and in the center of cavity structure and inhomogeneous structures.Treatment plans of different radiotherapy technologies were made generated and delivered on a linear accelerator.Then the TLD were read and analyzed.Results There were remarkable cavity effects of conventional single field,opposite fields and IMRT plans with 7 fields for head and neck phantom.There is similar effect in lung phantom.The more complexity the radiotherapy technology was the less cavity effect.Conclusions It is necessary to consider using more advanced radiotherapy technology or applying more fields to make treatment plans in order to decrease the cavity effect or similar effect when there are inhomogeneous structures.