著者

白石 順二

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.55, no.4, pp.362-368, 1999-04-20 (Released:2017-06-30)

参考文献数

17

被引用文献数

10 10

著者

安井 建造 本間 龍夫 三浦 正和

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.48, no.9, 1992

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.60, no.1, pp.141, 2004-01-20 (Released:2017-06-30)

著者

加藤 守 千田 浩一 盛武 敬 小口 靖弘 加賀 勇治 坂本 肇 塚本 篤子 川内 覚 松本 一真 松村 光章 大阪 肇 豊嶋 英仁

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.72, no.1, pp.73-81, 2016

被引用文献数

3

---

Deterministic effects have been reported in cardiac interventional procedures. To prevent radiation skin injuries in percutaneous coronary intervention (PCI), it is necessary to measure accurate patient entrance skin dose (ESD) and maximum skin absorbed dose (MSD). We measured the MSD on 62 patients in four facilities by using the Chest-RADIREC^Ⓡ system. The correlation between MSD and fluoroscopic time, dose area product (DAP), and cumulative air kerma (AK) showed good results, with the correlation between MSD and AK being the strongest. The regression lines using MSD as an outcome value (y) and AK as predictor variables (x) was y=1.18x (R²=0.787). From the linear regression equation, MSD is estimated to be about 1.18 times that of AK in real time. The Japan diagnostic reference levels (DRLs) 2015 for IVR was established by the use of dose rates using acrylic plates (20- cm thick) at the interventional reference point. Preliminary reference levels proposed by International Atomic Energy Agency (IAEA) were provided using DAP. In this study, AK showed good correlation most of all. Hence we think that Japanese DRLs for IVR should reconsider by clinical patients' exposure dose such as AK.

著者

加藤 守 千田 浩一 盛武 敬 小口 靖弘 加賀 勇治 坂本 肇 塚本 篤子 川内 覚 松本 一真 松村 光章 大阪 肇 土佐 鉃雄

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.70, no.8, pp.814-820, 2014

被引用文献数

1

---

In recent years, dose justification and optimization have been attempted in percutaneous coronary intervention (PCI); however, deterministic effects have been reported. To prevent radiation skin injuries in PCI, it is necessary to measure the patient entrance skin dose (ESD), but an accurate dose measurement method has not yet been established. In this study, we developed a dosimetry gown that can measure the ESD during PCI using multiple radiophotoluminescence dosimeters (RPLDs). The RPLDs were placed into 84 pockets that were sewn into a dosimetry gown. Patients wear the original dosimetry gown during the procedures, after which we obtain accurate ESD measurements. We believe that this method using RPLDs and a newly-designed dosimetry gown provides accurate ESD measurements during PCI. We expect this system to become a standard method for measuring ESD during PCI.

著者

片山 豊 上田 健太郎 日浦 慎作 木村 大輔 高尾 由範 山永 隆史 市田 隆雄 東山 滋明 河邉 讓治

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.74, no.7, pp.653-660, 2018 (Released:2018-07-20)

参考文献数

14

---

A high-resolution display panel comes to practical use, but the resolution of the indicated contents does not change. The up-sampling processing is applied to indication of the low-resolution contents. In the up-sampling process, the super resolution enables an up-sampling process which estimates information of high frequency components lost by sampling while analyzing input images is noticed. In this paper, we aimed at reconstructing an image of normal resolution in which the influence of statistical noise is reduced by applying super resolution after down-sampling processing is applied to positron emission tomography (PET) image with many statistical noises. To evaluate the noise reduction effect, we compared it with the Gaussian filter which is frequently used to reduce the influence of the statistical noise of the PET image. A 3D Hoffman brain phantom was used to evaluate objectively by peak signal-to-noise ratio and power spectral density. The objective index of the PET image applying super resolution is positive results, suggesting the possibility of being useful as compared with the conventional method.

著者

横山 三吉 菅原 健至

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

巻号頁・発行日

vol.32, no.5, 1977

著者

高羽 順子 升屋 亮三 斉藤 温己

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.47, no.10, pp.1856, 1991-10-01 (Released:2017-06-29)

著者

高羽 順子 升屋 亮三 池田 俊貴 中垣 五月 斉藤 温己

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.48, no.6, pp.958, 1992-06-01 (Released:2017-06-29)

著者

菊池 将司 林 則夫 鑓田 和真 坂田 梢 氏田 浩一 松田 悟志 手塚 雄一

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.72, no.11, pp.1169-1176, 2016

---

<p>During the arterial phase acquisition of Gd-EOB-DTPA examinations, use of a small volume of the Gd-EOB-DTPA may make it difficult the encoding center of the k-space, and produce blurring. The previous studies revealed the encoding technique of the k-space was one of the most important reasons. However, there is no report to discuss the reasons with quantitative evaluations. The purpose of this study was to quantitatively evaluate the characteristics of the artifacts using different k-space encoding techniques (centric-view ordering (CVO) and sequential-view ordering (SVO)) for liver dynamic MRI in computer simulation study. This simulation study consists of the following steps. First of all, the creation of a time intensity curve, and original simulation images at certain points among the one phase dynamic scanning. Secondly, creation-simulated MR echo data from the created original images using FFT, and encoding simulated k-space using the simulated MR echo data. Finally, a reconstruction of simulated dynamic MR images from the simulated k-space, and to evaluate each simulated MR images, we measured modulation transfer functions (MTFs) from the bar patterns of the reconstructed images. The results of the CVO simulation indicated that the bar patterns were blurring compared to the images encoded by the SVO. The results of the SVO simulation indicated that the bar patterns were not enhanced at late scan timings. In addition, the results of MTFs indicated that there was no edge enhancement at all scan timings and both encoding techniques. In conclusion, it is possible to quantitatively evaluate the characteristics of artifacts using MTF, which was measured by the bar patterns, in liver dynamic MRI.</p>

著者

辻 久志 林 万寿夫 浜田 松治 青木 明 井ノ崎 光彦 赤木 弘昭

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

巻号頁・発行日

vol.42, no.6, 1986

著者

畠中 史朗 杜下 淳次 樗木 晶子 野口 ゆかり 外園 栄作 小宮 陽子 東田 善治 島ノ江 信芳 中村 邦夫 田代 洋行

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.65, no.11, pp.1512-1518, 2009-11-25 (Released:2009-12-18)

参考文献数

12

---

Variation in the luminance ratio of a cathode ray tube(CRT)monitor and the ultrasonographic images at different levels of ambient light(0–150 lux)was investigated to obtain optimum ambient light in the ultrasonography suite. The maximum and minimum luminances of test patterns and ultrasonographic images were measured after three technicians independently optimized the brightness and contrast of the CRT monitor and ultrasonographic images at different levels of ambient light. Furthermore, the luminance ratio was calculated from the maximum luminance divided by the minimum luminance. When ambient light increased, it was difficult for the technicians to optimize the brightness and contrast settings of the CRT monitor to maintain a high luminance ratio at 0 lux. The luminance ratio decreased rapidly as ambient light increased up to 20 lux. However, the luminance ratio decreased gradually when ambient light was higher than 20 lux. It is necessary to take into consideration the ambient light to maintain a high luminance ratio of ultrasonographic images.

著者

伊藤 大輔 永坂 竜男 梁川 功 吉田 さやか 高瀬 圭

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.12, pp.1562-1567, 2008-12-20 (Released:2009-01-17)

参考文献数

5

被引用文献数

4 3

---

We studied the feasibility of high spatial and temporally resolved imaging by a combination of keyhole imaging, which is a fast imaging method, and a 3.0T MRI system which inherently has a high signal-to-noise ratio (SNR). In keyhole imaging, full k-space reference data are collected, followed by repeated dynamic acquisition of the central low-frequency data alone, and this makes dynamic acquisition faster. The purpose of our article is to describe the effects of the reference data on the reconstructed dynamic images with the assumption of vessel visualization. For efficient use of keyhole imaging, it is important to optimize the keyhole percentage and timing of reference data acquisition for the object of interest.

著者

宮井 將宏 山本 泰司 内部 拓 矢田 伸広 原元 益夫 勝部 敬 北垣 一

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.71, no.12, pp.1209-1214, 2015 (Released:2015-12-20)

参考文献数

15

被引用文献数

3 3

---

In the dopamine transporter scintigraphy there are two quantitative analysis softwares, DaTView and DaTQUANT. The quantitative value of both software has to be treated independently because there is a difference between them in the point of how to set the region of interest on the striatum and the background, calculation formula of quantitation. And also DaTQUANT has a capability of performing anatomical standardization which DaTView does not have. The aim of this study was to evaluate the accuracy of registration on DaTQUANT using a phantom, and to evaluate the correlation between the quantitative values between DaTView and DaTQUANT using clinical data. As a result, the accuracy of registration was acceptable. Regardless of the degree of accumulation in the striatum, there was a high correlation to each analysis software (r>0.85).

著者

高橋 信次

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.Special3, pp.161-173, 1958-06-15 (Released:2017-06-21)

著者

木村 英正 佐野 常晴 蕗 利彦 林 幸一 岩崎 千代子 板橋 慎二 小宮 秀朗 井上 清孝

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

巻号頁・発行日

vol.42, no.6, 1986

著者

小澤 文親 泉 和弥 有賀 康城 蕗 利彦

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

巻号頁・発行日

vol.48, no.9, 1992

著者

小澤 文親 泉 和弥 有賀 康城 蕗 利彦

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

巻号頁・発行日

vol.49, no.2, 1993

著者

小寺吉衞

出版者

Japanese Society of Radiological Technology

雑誌

日本放射線技術学会雑誌 (ISSN:03694305)

巻号頁・発行日

vol.62, no.5, pp.635-648, 2006

被引用文献数

1

著者

浜口 直子 小寺 秀一

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.4, pp.313-321, 2010-04-20 (Released:2010-07-08)

参考文献数

10

被引用文献数

3 5

---

It is a fact that image noise influences for image qualities of the brain CT are known widely. The same principle applies to 3D-CTA, image noise significantly influences the depiction of blood vessels. So we evaluated the use of CT-AEC for 3D-CTA to optimize the scan dose and control the depiction of cerebral vessels by CT-AEC. We decided to optimize the noise index (NI) for cerebral 3D-CTA through the use of an imitation blood phantom. In the evaluation of the depiction of the anterior choroidal artery that was able to be confirmed with DSA, the detection rate in high resolution mode: NI 6.0 was 70%. The depiction of the anterior choroidal artery became defective in the detailed exam mode: NI 7.0, low dose mode: NI 9.0 because of the noise. As for the existence of cerebral aneurysms, the sensitivities were 100% with DSA and 94.3% with 3D-CTA in detailed exam mode, and there was no statistical difference. The specificities of 3D-CTA had lowered to 92.6% and 97.2% in DSA. In low dose mode and detailed exam mode, DLP had decreased by 55.2% and 18.1% on the average compared to a fixed tube current (P<0.05). However, in high resolution mode, DLP increased by 5.9% on the average. It was necessary to limit the scan range to the region of interest when we used a fixed tube current. This clinical research verified that CT-AEC on cerebral 3D-CTA was useful for dose reduction and control of the depiction ability for inspection purposes.