Radiation Oncology Journal

The Korean Society for Radiation Oncology (대한방사선종양학회)
권호 표지

Patients Setup Verification Tool for RT (PSVTS) : DRR, Simulation, Portal and Digital images

방사선치료 시 환자자세 검증을 위한 분석용 도구 개발

  • Lee Suk (Department of Medical Physics, Kyonggi University) ;
  • Seong Jinsil (Brain Korea 21 Project for Medical Science) ;
  • Kwon Soo I1 (Department of Medical Physics, Kyonggi University) ;
  • Chu Sung Sil (Department of Radiation Oncology, Collage of Medicine, Yonsei University) ;
  • Lee Chang Geol (Department of Radiation Oncology, Collage of Medicine, Yonsei University) ;
  • Suh Chang Ok (Department of Radiation Oncology, Collage of Medicine, Yonsei University)
  • 이석 (경기대학교 대학원 의학물리학과) ;
  • 성진실 (Brain Korea 21 의과학사업단) ;
  • 권수일 (경기대학교 대학원 의학물리학과) ;
  • 추성실 (연세대학교 의과대학 방사선종양학교실) ;
  • 이창걸 (연세대학교 의과대학 방사선종양학교실) ;
  • 서창옥 (연세대학교 의과대학 방사선종양학교실)
  • Published : 2003.03.01

Abstract

Purpose : To develop a patients' setup verification tool (PSVT) to verify the alignment of the machine and the target isocenters, and the reproduclbility of patients' setup for three dimensional conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT). The utilization of this system is evaluated through phantom and patient case studies. Materials and methods : We developed and clinically tested a new method for patients' setup verification, using digitally reconstructed radiography (DRR), simulation, porial and digital images. The PSVT system was networked to a Pentium PC for the transmission of the acquired images to the PC for analysis. To verify the alignment of the machine and target isocenters, orthogonal pairs of simulation images were used as verification images. Errors in the isocenter alignment were measured by comparing the verification images with DRR of CT Images. Orthogonal films were taken of all the patients once a week. These verification films were compared with the DRR were used for the treatment setup. By performing this procedure every treatment, using humanoid phantom and patient cases, the errors of localization can be analyzed, with adjustments made from the translation. The reproducibility of the patients' setup was verified using portal and digital images. Results : The PSVT system was developed to verify the alignment of the machine and the target isocenters, and the reproducibility of the patients' setup for 3DCRT and IMRT. The results show that the localization errors are 0.8$\pm$0.2 mm (AP) and 1.0$\pm$0.3 mm (Lateral) in the cases relating to the brain and 1.1$\pm$0.5 mm (AP) and 1.0$\pm$0.6 mm (Lateral) in the cases relating to the pelvis. The reproducibility of the patients' setup was verified by visualization, using real-time image acquisition, leading to the practical utilization of our software Conclusions : A PSVT system was developed for the verification of the alignment between machine and the target isocenters, and the reproduclbility of the patients' setup in 3DCRT and IMRT. With adjustment of the completed GUI-based algorithm, and a good quality DRR image, our software may be used for clinical applications.

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