著者
安斎 育郎
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.36, no.2, pp.209-225, 1980
被引用文献数
2

Explanations were given as to the characteristic of the MIRD Committtee method for estimating the internal radiation doses due to the radioisotope administration, with special emphasis on the comparison with the method described in the ICRP Publication 2. The method evolved in the MIRD pamphlets have actually developed the accuracy of the calculation of the absorbed energy per disintegration of the radionuclide deposited in various organs, and it became more important to evaluate exactly the cumulated activity A^^〜 in the internal organs concerned. Some examples were selected for explaining how the MIRD pamphlets could practically be used, in which the author emphasized that the precise evaluation of the retention function, especially of its long-term components, was quite important for improving the accuracy of the dose assessment. The method for obtaining the "S" value for the organ mass that is different from that of the MIRD phantom was described. The author finally discussed the problem of estimating the mass of each internal organ out of the anthropometrical parameters such as body height and body weight.
著者
寺下 貴美
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.67, no.4, pp.413-417, 2011

研究方法論においてデータの性質から、数値で表されるデータを量的データ性質や特徴など数値で表せないデータを質的データという2つに分類される。 本稿では、質的データを扱う研究手法である質的研究手法に焦点を絞り、質的研究手法において理解すべき基本的項目を網羅的に紹介する。
著者
小沼 洋治 林 美智子 林 裕晃 西原 貞光
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.3, pp.277-282, 2012-03-20 (Released:2012-03-24)
参考文献数
12
被引用文献数
4

We tried to remove contamination of radioisotope (RI) for an X-ray detector (photostimulable phosphor plate; IP) and verified that our procedure suggested by Nishihara et al. was effective for decontamination. The procedure was as follows. First, the IP was kept for approximately twelve hours, and then it was processed [image (A)] as well as a clinical processing mode. Second, using a wet-type chemical wiper, we scavenged the IP to remove the adhered RI on its surface. Then, once again, the IP was kept for approximately fifteen hours and processed [image (B)] in order to check an effect of decontamination. Finally, the two images of (A) and (B) were analyzed using ImageJ, which can be downloaded as a free software, and a percentage of removal was calculated. The procedure was applied to two IPs using the FCR 5501 plus. In the present case, the percentage of removal was approximately 96%. The removed radioisotopes in the chemical wipers were analyzed by Ge detector. Then, 134Cs and 137Cs were found with activities of 2.9 4.3 Bq and 3.5 5.2 Bq, respectively. For three months after that, we cannot see black spots on the IPs owing to the contamination of the RI and there are no defects caused by decontamination using a wet-type chemical wiper.
著者
大塚 益比古
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.1212-1213, 2000-10-20
被引用文献数
2 1
著者
森下 雄太 宮地 利明 上田 丞政 清水 満 濱口 隆史 藤原 康博 林 弘之
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.64, no.5, pp.587-590, 2008-05-20 (Released:2008-05-29)
参考文献数
13
被引用文献数
1 1

The purpose of our study was to assess the mechanical effect on tattoo seals and eye makeup caused by a spatial magnetic gradient in the magnetic resonance imaging (MRI) system. Seven kinds of tattoo seals and three kinds of eye makeup, i.e., mascara, eye shadow, and eyeliner were used. On a 3.0-Tesla MRI, we determined these deflection angles according to a method established by the American Society for Testing and Materials (ASTM) at the position that produced the greatest magnetically induced deflection. Eighty-five percent of the tattoo seals showed deflection angles greater than 45 degrees of the ASTM guidelines, and the mascara and eye shadow showed over 40 degrees. This was because these contained ferromagnetic pigments such as an iron oxide, but those translational forces were very small owing to slight mass. However, it is desirable that these should be removed before MRI examination to prevent secondary problems.
著者
森下 雄太 宮地 利明 上田 丞政 清水 満 濱口 隆史 藤原 康博 林 弘之
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.64, no.5, pp.587-590, 2008-05-20
被引用文献数
1

The purpose of our study was to assess the mechanical effect on tattoo seals and eye makeup caused by a spatial magnetic gradient in the magnetic resonance imaging (MRI) system. Seven kinds of tattoo seals and three kinds of eye makeup, i.e., mascara, eye shadow, and eyeliner were used. On a 3.0-Tesla MRI, we determined these deflection angles according to a method established by the American Society for Testing and Materials (ASTM) at the position that produced the greatest magnetically induced deflection. Eighty-five percent of the tattoo seals showed deflection angles greater than 45 degrees of the ASTM guidelines, and the mascara and eye shadow showed over 40 degrees. This was because these contained ferromagnetic pigments such as an iron oxide, but those translational forces were very small owing to slight mass. However, it is desirable that these should be removed before MRI examination to prevent secondary problems.
著者
加藤 秀起 津坂 昌利 小山 修司 前越 久
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.54, no.5, pp.615-623, 1998-05-20
被引用文献数
1

An x-ray spectrum measured by a semiconductor detector is different from the incident x-ray spectrum to the detector, because of distortions caused by energy-dependent responses of the detector and statistical and electrical fluctuations in the signal amplifying process. In this paper, we discuss a method for correcting the statistical and electrical fluctuations of the x-ray spectrum, using the unfolding method with a function based on the Gaussian distribution. Unfolding the measured x-ray spectrum by this method, K-α and K-β characteristic x-rays were clearly separated into two line spectra, and energy resolution was improved. The unfolding method, when used to supplement the stripping method that is generally applied to x-ray spectra correction, will provide enhanced correction of x-ray spectra.
著者
小宮 勲 白坂 崇 梅津 芳幸 橘 昌幸 泉 隆
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.60, no.2, pp.270-277, 2004-02-20
参考文献数
20
被引用文献数
12

In this study, we investigated the usefulness of the fluorescent glass dosimeter for measuring patient dose. The fluorescent glass dosimeter is constructed of a glass element and its holder. One type has a tin (Sn) filter and the other does not. The characteristics of these two types of fluorescent glass dosimeters were studied in the range of diagnostic X-ray energy. The result was excellent for each characteristic. Directional dependency, however, was recognized in the fluorescent glass dosimeter with tin (Sn) filter. Based on these evaluations, patient skin dose was measured for abdominal interventional radiology and diagnostic digital subtraction angiography using the holder without filter, which is less direction-dependent and eliminates obstructive shadows in radiography and fluoroscopy. The average skin dose of 30 patients for abdominal IVR was 1.17±0.44 Gy (0.51-1.94 Gy), while those for diagnostic DSA examination was 0.54±0.21 Gy (0.15-1.02 Gy). The fluorescent glass dosimeter provides high capability for skin dose measurement. The fluorescent glass dosimeter is also useful for controlling patient dose during IVR procedures.
著者
鈴木 千晶 藤崎 賢二 渥美 雄介 竹村 実紀 水野 孝一 永峯 岳樹 天野 智康 山本 英雄 高橋 護
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.73, no.4, pp.273-281, 2017 (Released:2017-04-20)
参考文献数
22

The purpose of this study is to measure the hemodynamics on the effect of Valsalva maneuver aiming at pulmonary thromboembolism (PTE) using 2-dimensional (2D) phase contrast imaging of magnetic resonance image (MRI), Philips Ingenia 3.0-tesla (T). The maximal inspiration reduced the blood flow rate in various degrees at all measurement positions, superior vena cava (SVC), inferior vena cava (IVC), pulmonary artery (PA), ascending aorta (AA), and descending aorta (DA). This result suggests that the contrast effect in the PA might become weak during general PA phase to give a substantial influence of Valsalva maneuver in the condition after maximum inspiration. A contrast-enhanced computed tomography (CT) examination aiming at detection for PTE should be scanned without an advance maximum inspiration.