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Title: Development of dosimetry using detectors of diagnostic digital radiography systems

Abstract

Dosimetry using an imaging plate (IP) of computed radiography (CR) systems was developed for quality control of output of the x-ray equipment. Sensitivity index, or the S number, of the CR systems was used for estimating exposure dose under the routine condition: exposure dose from 1.0 to 1.0x10{sup 2} {mu}C kg{sup -1}, tube voltages from 50 to 120 kV, and added filtration from 0 to 4.0 mm Al. The IP was calibrated by using a 6 cc ionization chamber having traceability to the National Standard Ionization Chamber. The uncertainty concerning the fading effect was suppressed less than 1.9% by reading the latent image 4 min{+-}5 s after irradiation at the room temperature 25.9{+-}1.0 degree sign C. The S number decreased linearly on the logarithmic graph regardless of the beam quality as exposure dose increased. The relationship between the exposure dose (E) and the S number was fitted by the equation E=a{sup '}xS{sup -b}. The coefficient a{sup '} decreased when the added filtration and the tube voltage were increased. The coefficient b was 0.977{+-}0.007 in all beam qualities. The dosimetry using the IP and the equation can estimate the exposure dose in a range from 9.0x10{sup -2} to 5.0 {mu}C kg{supmore » -1} within an uncertainty of {+-}5% required by the Japanese Industry Standard. This dose range partially included the doses under routine condition. The doses between 1.0 and 1.0x10{sup 2} {mu}C kg{sup -1} under the routine condition can be shifted to the 5% region by using an absorber. The IP dosimetry is applicable to the quality control of the CR systems.« less

Authors:
; ; ; ;  [1];  [2];  [2];  [2]
  1. Graduate School of Environmental Studies, Nagoya University and Nagoya Daini Red Cross Hospital, 466-8650, Nagoya (Japan)
  2. (Japan)
Publication Date:
OSTI Identifier:
20853906
Resource Type:
Journal Article
Resource Relation:
Journal Name: Medical Physics; Journal Volume: 34; Journal Issue: 1; Other Information: DOI: 10.1118/1.2402911; (c) 2007 American Association of Physicists in Medicine; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
62 RADIOLOGY AND NUCLEAR MEDICINE; COMPUTERIZED TOMOGRAPHY; DOSIMETRY; FILTRATION; IONIZATION CHAMBERS; IRRADIATION; LATENT IMAGES; QUALITY CONTROL; RADIATION DOSES; SENSITIVITY; X-RAY EQUIPMENT

Citation Formats

Ariga, Eiji, Ito, Shigeki, Deji, Shizuhiko, Saze, Takuya, Nishizawa, Kunihide, Radioisotope Research Center, Nagoya University, 464-8602, Nagoya, Radioisotope Research Center, Tokushima University, 770-8503, Tokushima, and Radioisotope Research Center, Nagoya University, 464-8602, Nagoya. Development of dosimetry using detectors of diagnostic digital radiography systems. United States: N. p., 2007. Web. doi:10.1118/1.2402911.
Ariga, Eiji, Ito, Shigeki, Deji, Shizuhiko, Saze, Takuya, Nishizawa, Kunihide, Radioisotope Research Center, Nagoya University, 464-8602, Nagoya, Radioisotope Research Center, Tokushima University, 770-8503, Tokushima, & Radioisotope Research Center, Nagoya University, 464-8602, Nagoya. Development of dosimetry using detectors of diagnostic digital radiography systems. United States. doi:10.1118/1.2402911.
Ariga, Eiji, Ito, Shigeki, Deji, Shizuhiko, Saze, Takuya, Nishizawa, Kunihide, Radioisotope Research Center, Nagoya University, 464-8602, Nagoya, Radioisotope Research Center, Tokushima University, 770-8503, Tokushima, and Radioisotope Research Center, Nagoya University, 464-8602, Nagoya. Mon . "Development of dosimetry using detectors of diagnostic digital radiography systems". United States. doi:10.1118/1.2402911.
@article{osti_20853906,
title = {Development of dosimetry using detectors of diagnostic digital radiography systems},
author = {Ariga, Eiji and Ito, Shigeki and Deji, Shizuhiko and Saze, Takuya and Nishizawa, Kunihide and Radioisotope Research Center, Nagoya University, 464-8602, Nagoya and Radioisotope Research Center, Tokushima University, 770-8503, Tokushima and Radioisotope Research Center, Nagoya University, 464-8602, Nagoya},
abstractNote = {Dosimetry using an imaging plate (IP) of computed radiography (CR) systems was developed for quality control of output of the x-ray equipment. Sensitivity index, or the S number, of the CR systems was used for estimating exposure dose under the routine condition: exposure dose from 1.0 to 1.0x10{sup 2} {mu}C kg{sup -1}, tube voltages from 50 to 120 kV, and added filtration from 0 to 4.0 mm Al. The IP was calibrated by using a 6 cc ionization chamber having traceability to the National Standard Ionization Chamber. The uncertainty concerning the fading effect was suppressed less than 1.9% by reading the latent image 4 min{+-}5 s after irradiation at the room temperature 25.9{+-}1.0 degree sign C. The S number decreased linearly on the logarithmic graph regardless of the beam quality as exposure dose increased. The relationship between the exposure dose (E) and the S number was fitted by the equation E=a{sup '}xS{sup -b}. The coefficient a{sup '} decreased when the added filtration and the tube voltage were increased. The coefficient b was 0.977{+-}0.007 in all beam qualities. The dosimetry using the IP and the equation can estimate the exposure dose in a range from 9.0x10{sup -2} to 5.0 {mu}C kg{sup -1} within an uncertainty of {+-}5% required by the Japanese Industry Standard. This dose range partially included the doses under routine condition. The doses between 1.0 and 1.0x10{sup 2} {mu}C kg{sup -1} under the routine condition can be shifted to the 5% region by using an absorber. The IP dosimetry is applicable to the quality control of the CR systems.},
doi = {10.1118/1.2402911},
journal = {Medical Physics},
number = 1,
volume = 34,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}
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