Fully-deformable patient motion models from cone-beam CT for radiotherapy applications

17th International Conference on the Use of Computers in Radiation Therapy

物理学;计算机科学

Martin, J.^1 ; McClelland, J.^1 ; Yip, C.^2 ; Thomas, C.^3 ; Hartill, C.^2 ; Ahmad, S.^2 ; Meir, I.^4 ; Landau, D.^2 ; Hawkes, D.^1

Centre for Medical Image Computing, UCL, London, WC1E 6BT, United Kingdom^1

Department of Oncology, Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom^2

Medical Physics, Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom^3

Vision RT Ltd., Dove House, Arcacia Avenue, London, N3 2JU, United Kingdom^4

关键词: Fraction variation;    Motion correction;    Organs at risks;    Patient motions;    Radiotherapy applications;    Respiratory motions;    Scanner geometry;    Simulated phantom;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/489/1/012034/pdf
DOI  :  10.1088/1742-6596/489/1/012034

学科分类：计算机科学（综合）

来源: IOP

【 摘 要 】

We propose a method to build a fully deformable motion model directly from cone-beam CT (CBCT) projections. This allows inter-fraction variations in the respiratory motion to be accounted for. It is envisaged that the model be used to track the tumour, and monitor organs at risk (OAR), during gated or tracked radiotherapy (RT) treatment of lung cancer. The method is tested on CBCT projections from a simulated phantom in two cases. The simulations are generated from a patient respiratory trace and associated CBCT scanner geometry. Without and with motion correction, l2norm maximum errors were reduced from 24.5 to 0.698 mm in case 1, and 20.0 to 0.101 mm in case 2, respectively.