Development of a novel X-ray fluoroscopic motion tomography system for real time image guided tumor following radiation therapy

2019 Fiscal Year Final Research Report

• Project/Area Number: 17H04117
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Medical Physics and Radiological Technology
• Research Institution: Tohoku University
• Principal Investigator: Homma Noriyasu 東北大学, 医学系研究科, 教授 (30282023)
• Co-Investigator(Kenkyū-buntansha): 高井 良尋 一般財団法人脳神経疾患研究所, 南東北BNCT研究センター, センター長 (50107653)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 放射線治療 / 画像誘導 / 追尾照射

Outline of Final Research Achievements

In radiation therapy, intra-fractional tumor motion and deformation significantly limits the efficiency of radiation delivery and brings potential risk for organs around the tumor such as organs at risk. Conformable tumor following beam control is an ideal solution for such intra-fractional motion problem. In this study, a new real-time image processing method for tracking tumor motion and deformation has been developed. The proposed method is based on x-ray fluoroscopy to take advantage of real-time imaging the target tumor inside the body. However, the image quality of x-ray fluoroscopy is often not sufficient for tracking tumor due to superposition of bones or the other organs. To address this issue, a new stochastic partial tomographic reconstruction has been developed. Experimental results demonstrate that the proposed method outperforms the conventional methods and more importantly, they can achieve clinically useful performance.

Free Research Field

複雑系科学

Academic Significance and Societal Importance of the Research Achievements

本研究で開発した、新しい確率的部分断層再構成法は、x線透視による実時間性と、断層像の軟部組織描出能を両立させた画期的画像計測法である。これにより、照射中の腫瘍移動や変形を実時間で撮像することが可能になる。また、これまで開発してきた腫瘍移動予測法との組み合わせにより、腫瘍動態予測型の追尾照射を実現することで治療効果増大と副作用低減、さらには治療時間の劇的な低減を可能になる。これにより、患者ならびに術者の負担軽減をも実現する効果的な放射線治療への道を拓く成果である。