Real Time Computerized Portal Imager for High Energy Radiotherapy

Authors

  • ศุภชัย ชัยสวัสดิ์ หน่วยรังสีรักษา ภาควิชารังสีวิทยา คณะแพทยศาสตร์ มหาวิทยาลัยเชียงใหม่
  • ณัฐพล เลิศอนันต์พิพัฒน์ หน่วยรังสีรักษา ภาควิชารังสีวิทยา คณะแพทยศาสตร์ มหาวิทยาลัยเชียงใหม่

Abstract

The real time computerized portal imager was designed and constructed in Radiation Oncology Section, Faculty of Medicine, Maharaj Nakorn Chiang Mai Hospital, for radiotherapy treatment field verification. The 256 256 matrix ionization chambers were used as the radiation detectors. The analog signals from the detectors were converted to 12 bit digital signals. A portal image was then constructed from these digital signals by a personal computer. The obtained image with 64 gray shade could be adiusted for the desired windowing and leveling and recorded for later inspection or comparison. Comparing to the image from or dinary x-ray film technique using in our center, the quality of the one from our portal imager was better.

References

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Essers M, Boellaard R, van Herk M, Lanson H and Mijnheer B. 1996 "Transmission dosimetry with a liquid-filled electronic portal imaging device." Int. J. Radiation Oncology Biol. Phys. Vol.34, No.4, pp.931-941.

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Published

2025-04-03

How to Cite

1.
ชัยสวัสดิ์ ศ, เลิศอนันต์พิพัฒน์ ณ. Real Time Computerized Portal Imager for High Energy Radiotherapy. J Thai Assn of Radiat Oncol [internet]. 2025 Apr. 3 [cited 2025 Dec. 25];6(1-3):54-60. available from: https://he01.tci-thaijo.org/index.php/jtaro/article/view/278486

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Original articles