Breathing control with a visual signal for aperture maneuver with controlled breath (AMC)

  • Suh, Ye-lin (Department of Radiation Oncology, Asan Medical Center, University of Ulsan Collage of Medicine, Department of Physics, Ewha Womans University) ;
  • Yi, Byong-Yong (Department of Radiation Oncology, Asan Medical Center, University of Ulsan Collage of Medicine) ;
  • Ahn, Seung-Do (Department of Radiation Oncology, Asan Medical Center, University of Ulsan Collage of Medicine) ;
  • Klm, Jong-Hoon (Department of Radiation Oncology, Asan Medical Center, University of Ulsan Collage of Medicine) ;
  • Lee, Sang-Wook (Department of Radiation Oncology, Asan Medical Center, University of Ulsan Collage of Medicine) ;
  • Shin, Seong-Soo (Department of Radiation Oncology, Asan Medical Center, University of Ulsan Collage of Medicine) ;
  • Choi, Eun-Kyung (Department of Radiation Oncology, Asan Medical Center, University of Ulsan Collage of Medicine)
  • Published : 2004.11.26

Abstract

To appropriately control or compensate breathing motion of targets in thorax or abdomen during radiotherapy is still demanding. Our idea is that a visual signal may help regulate patient's breathing pattern, by controlling its amplitude and cycle. The system involving breathing control with a visual signal for aperture maneuver with controlled breath (AMC) has been developed. A thermocouple is used to detect the temperature change due to patient's breathing. The system also consists of a mask, in which the thermocouple is installed, an operational amplifier, a converter, etc. Patients were instructed to control their respiration by breathing following the visuals signal, as watching a display that shows both patients' current breathing pattern and the signal. The patterns of patients' controlled breathing and the signals coincided well. Therefore, when AMC technique is applied, a target moves in the range that is 60 % less than the range of free breathing motion with the help of the system and so target margins can be reduced significantly. This study reveals that a visual signal is not only useful to control patient's breathing but also clinically effective.

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