著者

坂本 肇 中村 修 弓削 誠 佐野 芳知 秋山 三郎 荒木 力

出版者

公益社団法人日本放射線技術学会

雑誌

日本放射線技術學會雜誌 (ISSN:03694305)

巻号頁・発行日

vol.56, no.10, pp.1256-1265, 2000-10-20

被引用文献数

26

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Total skin doses of patients resulting from interventional radiological procedures have the potential to exceed the threshold doses for deterministic effects such as erythema and epilation. It is desirable to measure entrance skin dose values non-invasively, easily, and at real time. If an acceptable mathematical equation could be established, the entrance skin dose could be calculated from the measured area exposure product. We established an equation to calculate the entrance skin dose from the measured area exposure product by creating calibration factors from phantom studies. In this report, entrance skin dose was calculated by using area exposure product and our established equation, and the calculated value was compared with that of the thermoluminescent dosimetric(TLD)value in a clinical setting. Although a significant correlation was found between the calculated and measured entrance doses, the deviation was about 10% in phantom studies and 20% in the clinical setting. Using our equation, calculation of ectrance skin dose is possible from area exposure product and is useful for patient dose control in the clinical setting.

著者

古屋 研 秋山 真治 中村 公二 佐野 芳知

出版者

公益社団法人 日本放射線技術学会

雑誌

日本放射線技術学会雑誌 (ISSN:03694305)

巻号頁・発行日

vol.68, no.7, pp.835-840, 2012-07-20 (Released:2012-07-23)

参考文献数

20

被引用文献数

1

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We measured the time-dependent change of computed tomography (CT) values for a blood sample in a syringe during 20 days expecting that the (average, maximum) CT values may be used to estimate the elapsed time after hemorrhage. The average CT value (CTave) rapidly increased for the first 50 min. The maximum CT value (CTmax) increased step by step to take the largest value (82.4 HU) one day later, and subsequently the CTmax decreased slowly to become 72.0 HU 20 days later. We conclude that the rapid increase of the CTave at the beginning is due to the fibrin generation, the increase of the CTmax is a result of the formation of the fibrin net, and the subsequent decrease of CTmax is caused by fibrinolysis. Tentative experimental formula for the time-dependent CTmax change at each increasing stage and decreasing stage are given to estimate the elapsed time after hemorrhage.