title: Development of fast patient position verification software using 2D-3D image registration and its clinical experience.
abstract: To improve treatment workflow, we developed a graphic processing unit (GPU)-based patient positional verification software application and integrated it into carbon-ion scanning beam treatment. Here, we evaluated the basic performance of the software. The algorithm provides 2D/3D registration matching using CT and orthogonal X-ray flat panel detector (FPD) images. The participants were 53 patients with tumors of the head and neck, prostate or lung receiving carbon-ion beam treatment. 2D/3D-ITchi-Gime (ITG) calculation accuracy was evaluated in terms of computation time and registration accuracy. Registration calculation was determined using the similarity measurement metrics gradient difference (GD), normalized mutual information (NMI), zero-mean normalized cross-correlation (ZNCC), and their combination. Registration accuracy was dependent on the particular metric used. Representative examples were determined to have target registration error (TRE) = 0.45 ± 0.23 mm and angular error (AE) = 0.35 ± 0.18° with ZNCC + GD for a head and neck tumor; TRE = 0.12 ± 0.07 mm and AE = 0.16 ± 0.07° with ZNCC for a pelvic tumor; and TRE = 1.19 ± 0.78 mm and AE = 0.83 ± 0.61° with ZNCC for lung tumor. Calculation time was less than 7.26 s.The new registration software has been successfully installed and implemented in our treatment process. We expect that it will improve both treatment workflow and treatment accuracy.
authors.affiliation: Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Inage-ku, Chiba 263-8555, Japan shinshin@nirs.go.jp.
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Mori
authors.affiliation: Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Inage-ku, Chiba 263-8555, Japan.
authors.forename: Motoki
authors.initials: M
authors.lastname: Kumagai
authors.affiliation: Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Inage-ku, Chiba 263-8555, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Miki
authors.affiliation: Research Center for Frontier Medical Engineering, Chiba University, Japan.
authors.forename: Riki
authors.initials: R
authors.lastname: Fukuhara
authors.affiliation: Research Center for Frontier Medical Engineering, Chiba University, Japan.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Haneishi
mesh_terms: D000465:Algorithms; D002244:Carbon; D003196:Computer Graphics; D004867:Equipment Design; D006258:Head and Neck Neoplasms / Q000532:radiotherapy; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D007477:Ions / Q000627:therapeutic use; D008175:Lung Neoplasms / Q000532:radiotherapy; D008297:Male; D015233:Models, Statistical; D056888:Patient Positioning; D011471:Prostatic Neoplasms / Q000532:radiotherapy; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D012984:Software; D014057:Tomography, X-Ray Computed; D014965:X-Rays
chemical_list: D007477:Ions; D002244:Carbon
keywords: 2D/3D registration; GPU; interfractional changes; patient set-up; radiotherapy