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[in Japanese]
2005 Volume 22 Issue 1 Pages
2
Published: January 01, 2005
Released on J-STAGE: October 02, 2007
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Hidefumi SUZUKI
2005 Volume 22 Issue 1 Pages
3-13
Published: January 01, 2005
Released on J-STAGE: October 02, 2007
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Yoshihiko HAYAKAWA, Yuji KOUSUGE, Tsukasa SANO, Kazuhiro YAMAMOTO, All ...
2005 Volume 22 Issue 1 Pages
14-21
Published: January 01, 2005
Released on J-STAGE: October 02, 2007
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Rika BABA
2005 Volume 22 Issue 1 Pages
22-28
Published: January 01, 2005
Released on J-STAGE: October 02, 2007
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Fumio NAKAGAWA, Satoshi YANAGITA
2005 Volume 22 Issue 1 Pages
29-34
Published: January 01, 2005
Released on J-STAGE: October 02, 2007
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With the mobile X-ray unit equipped with the FPD for the purpose of widening a range of applications of FPD in ordinary radiography field, we have conducted clinical tests of the equipment at Kitasato Institute Medical Center Hospital to evaluate usefulness and advantages or disadvantages of the mobile X-ray unit mounted with the FPD.As the result, we have received the report that the equipment is useful for clinical examination in the words, emergency room and operating theater. This paper reports technical aspects of the X-ray mobile unit mounted with the FPD.
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Keisuke HASHIMOTO, Kyojiro NAMBU, Shigeharu OHYU
2005 Volume 22 Issue 1 Pages
35-41
Published: January 01, 2005
Released on J-STAGE: October 02, 2007
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We are developing a new volumetric imaging system with a flat panel detector (FPD), Digital Volume Tomography(DVT) system, which applies the principle of digital tomosynthesis. The system is compact and openspaced as an intra-operative imaging tool to visualize a small region covering the surgical target without any changes to surgical setup including a microscope and surgical tools. With obtained images of high resolution and wide dynamic range, the DVT system can help the surgeon to confirm the orientation of surgical field. Furthermore, by vessel information extracted from DVT images overlaid on the live video of surgical microscope, the surgeon can easily recognize the hidden vessels under the surface. Therefore, the DVT system is expected to be a useful imaging component of the surgical navigation system.
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Koichi SHIBAKUSA
2005 Volume 22 Issue 1 Pages
42-49
Published: January 01, 2005
Released on J-STAGE: October 02, 2007
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Hiroyuki TAGASHIRA, Natsuko BANDAI, Kenji ARAKAWA, Masahiro YOSHIMOTO, ...
2005 Volume 22 Issue 1 Pages
50-56
Published: January 01, 2005
Released on J-STAGE: October 02, 2007
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The purpose of this study was to evaluate the detectability of Flat Panel Radiography(Revolution XQ/i : pixel size of 200μm)with and without dual energy subtraction for diagnosing subtle lung abnormalities. We studied the differences of observer performance between the digital radiography with dual energy subtraction and that without dual energy subtraction.In this study, we prepared the simulating subtle lung nodules, which were made of acrylic resin.Simulated abnormalities were placed on the back of the chest phantom,and they were examined using the same exposure condition. A total of 160 chest images were obtained, in which 80 chest images had the simulated nodule,the other 80 chest images had no nodule.Three chest radiologists interpreted these 160 chest images using continuous confident scale.The results of interpretation were analyzed by using ROC analysis, and the Az values(area under the ROC curve)were compared.Flat Panel Radiography with dual energy subtraction showed significantly better result(Az = 0.943), followed by without dual energy subtraction(Az = 0.795). Dual energy subtraction tool would be promising in clinical practice.
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: Visual Evaluation of the Voltage Combination by the Normalized-Rank Approach
Natsuko BANDAI, Hiroyuki TAGASHIRA, Shinji WATANABE, Masahiro YOSHIMOT ...
2005 Volume 22 Issue 1 Pages
57-64
Published: January 01, 2005
Released on J-STAGE: October 02, 2007
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The new dual-energy subtraction system allows the fast (200 millisecond) acquisition of two, high and low voltage images using CsI : Tl amorphous silicon flat-panel technology. The purpose of this study was to determine the best combination of the voltage for the soft tissue image of the chest radiography. The dual-energy subtraction imaging increases the sensitivity and specificity of the pulmonary nodule detection in the chest radiography by reducing the contrast of overlying the bone structures. The range of the high and low voltage we used was from 120kV to 150kV and 60kV to 80kV, respectively. Six radiographers evaluated these images with the normalized-rank approach. All rank orders were transformed to the distance scale by the statistical method. The ranking in the low voltage was better in the order corresponding to 60kV, 70kV and 80kV ( p < 0.05 ) . The ranking in the high voltage with fixed low voltage 60kV showed better in the order corresponding to 140kV, 150 kV, 130kV and 120kV. The best combination for the soft tissue image of the chest in this system was 140kV (high voltage) and 60kV (low voltage) .
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Satoshi YANAGITA, Masako HITACHI, Tomoyuki SAKURAI, Yoshihiro SUZAKI, ...
2005 Volume 22 Issue 1 Pages
65-72
Published: January 01, 2005
Released on J-STAGE: October 02, 2007
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We had an opportunity to use the 35cm x 43cm portable FPD with the mobile x-ray system in the cooperative research with Hitachi Medical Corporation and Canon Inc from February 2004. We have conducted the following three experiments to verify the clinical effectiveness; 1. to measure the maximum exposure times possibly conducted with fully-charged battery on the mobile X-ray system, 2. to compare the mobile FPD system with conventional CR system in term of workflow, 3. to conduct the visibility test on various-sized intravenous hyper alimentation(IVH) catheters by viewing on the 10.4 inch TFT monitor of the laptop pc(being used as the operation unit for the FPD system). The results are as follows; 1. 191 exposures and image capturing were done, 2. The 9 steps of the procedures with the CR could be reduced to 5 steps with the mobile FPD system. 3. The tips of the catheters from 14G to 18G could be observed. The mobile FPD system provides immediate image viewing and can be used for various clinical applications. The system is also expected to be used effectively even in emergency or disastrous situations.
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Yuriko OHTANI, Shigeru SANADA, Koichiro UEKI, Takeshi MATSUI, Natsuko ...
2005 Volume 22 Issue 1 Pages
73-78
Published: January 01, 2005
Released on J-STAGE: October 02, 2007
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The purpose of this study is to develop the method of quantitative analysis of the temporomandibular joint (TMJ) kinetics using a dynamic flat panel detector (FPD) system. Axially positioned dynamic radiographs of the TMJ were obtained during opening and closing of the mouth using FPD system (Modified CXDI-40G, CANON) . The entrance surface dose was 1.7 times that of conventional imaging. The subjects were two asymptomatic volunteers and one symptomatic volunteer who had a click on the right TMJ. The accumulated image subtraction technique was used to enhance the mandibles and then we manually measured the medial point of the condyle and incisor. In the case of the subject with TMD symptom, there were lateral deviation in the incisal path and the changes in the maximum velocity of condyle were found. This may be caused by the clicking disorder. Our new method provides detailed dynamic data concerning the movement of the condyle in the TMJ. This data can be used to assist in the diagnosing of pre-and post-operative temporomandibular disorder patients.
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Yuuki WAIZUMI, Shigeru SANADA, Masayuki SUZUKI, Takeshi MATSUI, Osamu ...
2005 Volume 22 Issue 1 Pages
79-83
Published: January 01, 2005
Released on J-STAGE: October 02, 2007
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It comes to be able to perform screening test which added functional information simply by using the modified flat panel detector(FPD). The purpose of this research is analyzing the dynamic state of heart wall from sequential chest images at the short period by the modified FPD. The heart beat process, peak expiratory and respiratory pause, was taken in three healthy volunteers and a patient of ischemic heart disease. Horizontal movement of heart wall in the left atrium, the left ventricle, and the cardiac apex part were analyzed for the sequential 30 images(6 frame/sec x 5sec). The result was approximated to the sign curve and amplitude(move distance of heart wall) and frequency(heart rate) were analyzed. Compared with the normal case, abnormal case's pulsation in the left ventricle and the cardiac apex part were small, and its cycle was also irregular than the analysis result. It is suggested that this method is useful as heart dynamic examination to diagnosis of angina, myocardial infarction, etc. which cause abnormalities of heart wall movement.
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Shinichi SUNAGA, Hiroyuki NAGASHIMA, Kouji SUZUKI, Eiichi KOYA, Toshih ...
2005 Volume 22 Issue 1 Pages
84-90
Published: January 01, 2005
Released on J-STAGE: October 02, 2007
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In the diagnostic area using X-rays, it has shifted to the digital system by computed radiography and flat-panel detector (FPD) from the analog system by screen film. Research team from the Japanese Society of Radiological Technology constructed quality assurance program of CR system in 2001. This program has contributed to performance maintenance and security of a system greatly. However, in FPD which attracts attention as new detector, the protocol about a quality control and performance evaluation is not examined. This study referred to quality assurance program of CR system, and constructed the quality control protocol of FPD system. Furthermore, we have grasp of change on standing of the FPD system in this facility, and evaluated the quality control program which constructed. Consequently, the constructed quality control program made it possible to be able to carry out simple on user side. Although the quality control program constructed by this study has minor improvements, medical treatment with high quality can be offered, since keeping performance and grasp of image quality and exposure dose are expected.
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Atsushi FUKUYAMA, Satoshi ANDO, Kazushi IDA, Tomoaki SUZUKI, Kayoko MA ...
2005 Volume 22 Issue 1 Pages
91-96
Published: January 01, 2005
Released on J-STAGE: October 02, 2007
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The film processors used by a screen-film system is decreasing recently, it became impossible to develop Duplicating-Film used conventionally. The purpose of this study was to evaluate the usefulness of the new method of duplicating a film using Computed Radiography (CR) system. We evaluated by creating a Contrast-Detail (C-D) curve and Image Quality Figure (IQF) about three systems of Original film, the film duplicated using Duplicating-film (Duplicating-film) and the film duplicated using CR system (CR-Dup film). Those films were read by Six radiologists and fourteen radiological technologists. For Original film and Duplicating-film reading, analog images were printed on 10×12-inch films. For CR-Dup film, 10-bit images obtained by CR system were printed on B4 size films. For Original film, Duplicating-film and the CR-Dup film, IQF were 87.7, 89.3 and 96.6, respectively. There were no statistically significant differences between these values (paired T-test p<0.05). The ability to diagnose on radiography did not differ for Original film, Duplicating -film and the CR-Dup film. It is recognized that the new Method of Duplicating of a film using CR system can fully be used in clinical.
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