2015 Fiscal Year Research-status Report
モバイルガンマカメラを用いて腔内照射中の形態画像上４次元線量分布の可視化に挑む
| Project/Area Number |
26670301
|
|---|
| Research Institution | Kyushu University |
|---|
Principal Investigator |
有村 秀孝 九州大学, 医学(系)研究科(研究院), 教授 (20287353)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
中村 和正 浜松医科大学, 医学部, 教授 (20284507) [Withdrawn]
藤淵 俊王 九州大学, 医学(系)研究科(研究院), 講師 (20375843)
|
|---|
| Project Period (FY) |
2014-04-01 – 2017-03-31
|
| Keywords | brachytherapy / uterine cervical cancer / Monte Carlo simulation / tissue heterogeneity / computed tomography |
|---|
| Outline of Annual Research Achievements |
Intracavitary brachytherapy (ICBT) with high-dose-rate (HDR) 192Ir can intensively deliver high dose to uterine cervical tumors. Moreover, it could cause little damage to normal tissues surrounding the tumors owing to the steep dose gradients produced by low energy γ rays (mean energy for 192Ir: 360.7 keV) in ICBT. Although human bodies have been considered homogeneous, latest treatment planning systems have started to take into account the heterogeneity of human bodies by using a dose calculation algorithm of Boltzmann transport equation solver. Nevertheless, Monte Carlo (MC) simulation provides the most reliable results because of a rigorous approach to simulate photon transport.
The main aim of this study was to investigate the influence of tissue heterogeneity of human bodies on dose distributions in intracavitary brachytherapy for uterine cervical cancer using HDR 192Ir by performing the MC simulation on a planning computed tomography (CT) image. Since the discrepancies of between two dose distributions in the CT image and water phantom were found around the applicator, the impact of the tissue heterogeneity on dose distributions could not be negligible.
|
| Current Status of Research Progress |
Current Status of Research Progress
2: Research has progressed on the whole more than it was originally planned.
Reason
Currently, we are developing a theory and designing a whole system including a pinhole collimator using a Monte Carlo simulation.
|
| Strategy for Future Research Activity |
We will develop a system with a mobile gamma camera, which can identify the seed locations without using any x-ray imaging systems. For that purpose, we are going to develop a theory of identification of seed locations and design the whole system using a Monte Carlo simulation.
|
| Causes of Carryover |
We submitted our paper to Journal of Radiation Research, and we were going to pay the publication fee until the end of FY2015, but our paper has been accepted around the end of FY2015. Therefore, we were not able to pay the publication fee.
|
| Expenditure Plan for Carryover Budget |
W will pay the publication fee in FY2016.
|
