著者
山口 紘子 松本 光弘 太田 誠一 植田 崇彦 筒井 保裕
出版者
Japanese Society of Radiological Technology
雑誌
日本放射線技術學會雜誌 (ISSN:03694305)
巻号頁・発行日
vol.68, no.5, pp.602-607, 2012-05-20

<i>Introduction</i>: We verified the setup error (SE) in two persons' radiation therapist's team, which consist of staff and new face. We performed the significance test for SE by the staff group and the new face group. <i>Methods</i>: One group consists of four staff therapists with at least 5 to 30 years of experience. The other group consists of new face radiation therapists that have 1 to 1.5 years of experience. Analyzed were 53 patients diagnosed with pelvic cancer (seven patients who underwent 3 dimensional conformal radiation therapy (3DCRT) and 46 patients who underwent intensity modulated radiation therapy (IMRT). Image verification was 1460 times. It was performed through setup verification by cone beam computed tomography (CBCT), and we measured SE of four directions (lateral, long, vertical, 3D). We performed the student's t-test to get the difference of the average error between the staff group and the new face group. <i>Results</i>: The results of significance tests show that there is no difference between SE in the staff group and the new face group in radiotherapy.
著者
金場 敏憲
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.38, no.1, pp.16-26, 1982-01-01

Standard base lines in skull radiography are important technical factors for high quality reproduction of a radiogram. However, in current texbooks of radiology and radiography, at least 11 base lines have been described for skull radiography. The definition of these base lines has been by no means uniform or precise among the various authors. In our attempt for some standardization, two fundametal base lines, the ABL and the OMBL were chosen and upon a study of their histological development, the present status of their clinical use in various countries were analyzed. We also investigated about the reference point considered in those base lines. The difference in the angle taken for the ABL and the OMBL estimation has been described in the literature, as being 10 degree, but we found that this angle measured over the skin surface varied widely among individuals ranging from 9 to 16 degree. Thus, we concluded that accurate standardization of radiographic base lines are essential for an improvement of skull radiography. Our results indicated the need to recognize existing differences on reference points or lines taken on the skin surface or over the bone position.
著者
小林 昌樹 小林 正人 染野 竜也 内山 弘実 小野 祐樹
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.10, pp.1314-1319, 2011-10-20 (Released:2011-10-26)
参考文献数
5
被引用文献数
1

In Japan, various types of MRI equipment, having varying magnetic field strengths, are widely used. However, the biggest problem encountered while utilizing an MRI is the scarcity of information and guidelines pertaining to implants, internal, and external metallic objects. This leads to uncertainty when an unspecified object is encountered during an examination andcreates the possibility of performing an ambiguous MRI. Therefore, this study classified a range of objects into 12 categories using database management software. An attempt was made to create an environment where reference and comparison of products could be performed. This study also investigated the ways and extent to which medical equipment package inserts reference the MRI. With the co-operation of various corporations and the use of information such as medical equipment package inserts, product information was collected and an environment for the reference and comparison of products became available. In addition, it became apparent while examining these package inserts that orthopedic products had the least information available. It is likely that this information will be useful in medical settings and this kind of database will become increasingly necessary in the future.
著者
足立 宏美 稲越 英機 早川 岳英 井上 富夫 笠原 敏文 五十嵐 智 早川 英樹 棚邊 哲史
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.3, pp.306-315, 2008-03-20
被引用文献数
2 2

To estimate the collimator scatter factor, <i>S</i><sub>c</sub> of small field sizes in which a mini-phantom cannot be fully included at the nominal treatment distance (NTD=100 cm), we measured the in-air output of 4 MV and 10 MV X-rays of a Varian's Clinac 2100 C/D using a mini-phantom at NTD and at a long source-to-chamber distance (SCD=200 cm) with field-size defined at the isocenter down to 4.6×4.6cm<sup>2</sup> and 2.3×2.3cm<sup>2</sup>, respectively. We then compared the fitted curve to the NTD dataset by a cumulative exponential distribution model with that by a cumulative Gaussian distribution (error function) model containing a zero-field extrapolated term derived from the long SCD dataset. The results showed that the zero-field extensions of two fitted curves coincided for a 4 MV X-ray, but a large discrepancy was seen between them for a 10 MV X-ray. Therefore, the <i>S</i><sub>c</sub> of small field sizes not measurable using a mini-phantom at the NTD can be well estimated by applying the cumulative exponential model to the NTD dataset in the case of a 4 MV X-ray beam filtrated with a cone-shaped flattener. However, to estimate the <i>S</i><sub>c</sub> of such small field sizes in the case of a 10 MV X-ray beam filtrated with a bell-shaped flattener, we consider it preferable to also measure in-air output at a long SCD and to apply the cumulative Gaussian model as described here.
著者
水谷 武雄 木村 千明 福島 重喜
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.47, no.8, 1991-08-01

理想的な空間的線量分布を得ることは、即治療成績に大きく関与することは言及するまでもなく、常に、最良な線量分布の改善と努力が大切であろう。図-3は、図-2中の前後方向の線量変化の程度を打抜材質を変えて調べた図で、ヘビーメタル粒状の優位性が示されている。さらに、適応の拡大を検討中である。
著者
新開 英秀 江副 正輔 重谷 昇 入江 聖義 泉 隆 穴井 重男
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.50, no.9, pp.1565-1572, 1994-09-01
被引用文献数
8

X線検査, 特に透視撮影装置における患者被曝線量を測定する目的で試作した二重電極型電離箱・増幅器の概要を述べ, この特性に関する基礎実験の結果について言及した.1)電離箱は0.1mmポリエステルフィルムと15μm厚のアルミニウム箔を使用し壁厚を極力薄くしたため, アルミニウム当量も0.13±0.01mmAlとなり, 線質依存性はX線検査に多用される60kV〜120kVの範囲では実用上問題にならない範囲であると考える.2)線量特性については60kV, 80kV, 100kV, 120kVでよく直線性が保たれている.3)電極間距離を5mmとして, 低電圧でも十分な収集効率が得られるようにしたため, 透視撮影装置で使用する線量率の範囲[4×10^<-4>(C/kg)/sec〜55×10^<-4>(C/kg)/sec]でもそれぞれ-2%, -6%以内の線量率依存性となり, よい特性を示した.4)集電電極(1)の電離箱は4cm×4cm以上の面積で, 集電電極(2)の電離箱では13cm×13cm以下の面積で使用すれば, この二重電極型電離箱の使用目的を十分発揮できることになる.通常の透視撮影装置においては, この条件を満たすものと考える.5)増幅器も線量計として十分な性能をもつものが製作できた.この二重電極型電離箱を可動絞り前面位置に取り付けることにより, 透視検査時の照射線量・面積照射線量の測定が可能である.われわれは, この線量計を8台の透視撮影台に設置し臨床使用している.
著者
小笠原 克彦
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.66, no.6, pp.668-672, 2010-06-20 (Released:2010-08-10)
参考文献数
21
被引用文献数
3 2 2
著者
長尾 一 箱田 光世 清藤 絵里 渡部 賢仁
出版者
Japanese Society of Radiological Technology
雑誌
日本放射線技術學會雜誌 (ISSN:03694305)
巻号頁・発行日
vol.67, no.1, pp.15-24, 2011-01-20

We have made new instructions with onomatopoeic sounds and their own signs in order to improve the accuracy of the upper gastrointestinal study, and compared these new instructions with the conventional ones. After the examinations, we asked the patients to fill out a questionnaire regarding how they felt about the new instructions. In the esophagus X-ray fluoroscopy, the number of patients who took the proper amount of Barium meal showed a rate of increase of 31.6 percent compared to the conventional method. For the patients' movements in the right rotation direction, the number of the patients showed a rate of increase of 18.2 percent using the oral instructions with onomatopoeic sounds, and 25.0 percent using the oral instruction with onomatopoeic sounds and signs. From the results of the questionnaire, 87.6 percent of the patients answered that the signs were "Effective" or "Very Effective." Including the answer "Doesn't Matter," the sign instructions being useful increased to 94.8 percent of the patients. Ninety-four point eight percent of the patients answered that the oral instructions during this X-ray examination were "Easy To Understand" or "Very Easy To Understand." With these results, I believe we should give the oral instructions using onomatopoeic sounds and signs.