-
Article type: Cover
2001 Volume 57 Issue 7 Pages
Cover24-
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
Article type: Cover
2001 Volume 57 Issue 7 Pages
Cover25-
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
Article type: Index
2001 Volume 57 Issue 7 Pages
Toc19-
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
Article type: Index
2001 Volume 57 Issue 7 Pages
Toc20-
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
Article type: Appendix
2001 Volume 57 Issue 7 Pages
I-XXI
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
EITARO NISHIHARA, [in Japanese], [in Japanese]
Article type: Article
2001 Volume 57 Issue 7 Pages
747-750
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
MAKOTO TSUCHIMOCHI
Article type: Article
2001 Volume 57 Issue 7 Pages
751-758
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
TSUKASA TOMIYOSHI
Article type: Article
2001 Volume 57 Issue 7 Pages
759-764
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
KOUZO KUMAGAI
Article type: Article
2001 Volume 57 Issue 7 Pages
765-
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
MASAHIKO OKUMURA
Article type: Article
2001 Volume 57 Issue 7 Pages
766-770
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
HIROSHI OGUCHI
Article type: Article
2001 Volume 57 Issue 7 Pages
771-777
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
YOSHIHARU WATANABE
Article type: Article
2001 Volume 57 Issue 7 Pages
778-783
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
KOUZO KUMAGAI
Article type: Article
2001 Volume 57 Issue 7 Pages
784-790
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
CHUDO KAZUSA
Article type: Article
2001 Volume 57 Issue 7 Pages
791-795
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
Kazuo Shimura
Article type: Article
2001 Volume 57 Issue 7 Pages
796-802
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
KEIICHI ODA
Article type: Article
2001 Volume 57 Issue 7 Pages
803-805
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
TSUGUNORI IWAI
Article type: Article
2001 Volume 57 Issue 7 Pages
806-807
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
KIYOSUMI KAWAMOTO
Article type: Article
2001 Volume 57 Issue 7 Pages
808-813
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
KEN MAEDA
Article type: Article
2001 Volume 57 Issue 7 Pages
814-815
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
Article type: Appendix
2001 Volume 57 Issue 7 Pages
816-819
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
SHU IKEDA, MASAO TAKAHASHI, MASAYUKI TSUDA
Article type: Article
2001 Volume 57 Issue 7 Pages
821-828
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
The use of digital simultaneous multi-plane tomography with digital x-ray TV provided highly precise and informative tomograms with minimal burden on the patient. Compared with helical CT, the method offered a much lower exposure dose and shorter examination time. In this method, first the projection data were collected, and then the tomograms were reconstructed. Arbitrary planes of the tomogram were, therefore, obtainable from single-acquisition data. Multiple tomograms without gaps between each plane were also obtained from the projection data. During reconstruction of the tomogram, the various causes of image distortion were corrected using data obtained with the specially designed calibration phantom. Images of hip joint, mandible, and larynx have been obtained so far, and images were of high quality. Exposure dose to the patients was less than that of conventional analog tomography. Various images were obtainable with image processing. For example, a curved surface image could be reconstructed for fitting the curvature of the mandible. The reconstructed tomograms were able to be displayed in various forms, including maximum intensity projection.
View full abstract
-
JUNJI MORISHITA, SHIGEHIKO KATSURAGAWA, KUNIO DOI
Article type: Article
2001 Volume 57 Issue 7 Pages
829-836
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
We have been developing an automated scheme of computer-aided diagnosis(CAD)for detection of lung nodules based on a difference-image approach in which a nodule-suppressed image is subtracted from a nodule-enhanced image. To further improve the performance of the scheme, we need to reduce the number of false positives and increase the sesitivity for detection of nodules. In this study, we focused on elimination of false positives of pulmonary nodules. First, we investigated an automated extraction method for nodules in a difference image and calculated various measures related to the shape of nodule candidates. Then we analyzed those measures to reduce false-positive detection. Our results indicated that 94 ROIs(13.5%)in the 696 false-positive ROIs were eliminated by using the method described in this study, whereas no true positive ROIs were eliminated. We conclude that our method based on shape analyses would be useful to eliminate some of the difficult false positives in the current CAD scheme.
View full abstract
-
TOMOYUKI MARUYAMA, TSUNEO WATANABE, YOSHIHIKO KAWAMURA
Article type: Article
2001 Volume 57 Issue 7 Pages
837-844
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
The current frequency processing of computed radiography(CR)is done by an unsharp masking(USM)filter. It emphasizes the noise of CR that influences the high-frequency wave component on the harmonic wave for the rectangular wave. In this study, we measured the overall Wiener spectrum(WS)of the multi-objective frequency processing(MFP)filter and the USM filter. The newly developed MFP is like a Gaussian curve for the imaging forms of processing on smoothing, and its noise properties are better than those of the USM filter. MFP has multi-frequency balance types(MRB)ranging from the "A-type"to"F-type, "and the overall Wiener spectral value decreases stepwise from"A-type"to"F-type." An important function of MFP is that processing emphasizes depression in which conversion by non-linear function depends on contrast, so that overall Wiener spectral values from 0.1-2.0 cycles/mm of spatial frequency decrease to the low frequency wave band. In this way MFP is more similar to conventional film than processing by USM.
View full abstract
-
SEIICHI MURAKAMI, NOBUHIRO ODA, HAJIME NAKATA, ETSURO FUTAGAMI, KEIJI ...
Article type: Article
2001 Volume 57 Issue 7 Pages
845-852
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
A difference in the inspiration lung volume between previous and current chest radiographs may cause an artifact similar to ground-glass opacity on temporal subtraction images. We examined this artifact using the chest computed radiography(CR)images with different inspiration volumes of normal volunteers. This artifact caused by a difference in the inspiration volume between previous and current chest radiographs did not appear in upper and middle lung fields, but was recognized only in the lower lung field overlying the diaphragm. When the difference in inspiration volume for a temporal subtraction image was about 20% of vital capacity, the fractional area with the artifact was about 4% of the total area of the lung field, and the remaining 96% of the lung field showed good subtraction images without artifacts. We conclude that the artifact of a temporal subtraction image caused by the difference in the inspiration volume was small and would not be an obstacle to diagnosing diffuse ground-glass opacity encountered in various diffuse interstitial lung diseases.
View full abstract
-
YASUHITO HIROSHIMA, SEIICHI FUJIWARA, MASAKI TOKITA
Article type: Article
2001 Volume 57 Issue 7 Pages
853-859
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
This study was a comparison of the Bubeck and Russell(1996)methods, both of which are used to calculate ^<99m>Tc-MAG_3 plasma clearance by single blood sampling in consideration of the distribution volume of patients. Quadratic polynominal approximation showed a strong correlation between the plasma clearance values obtained by the two methods. The quantitative values obtained by the Bubeck method tended to be lower than those obtained by the Russell(1996)method in the high clearance range. However, in the low to medium clearance range(below 250 ml/min/1.73m^2), there was almost no difference between the values, and the relationship between the values obtained by the two methods could be expressed by a straight regression line. A comparison of plasma clearance values according to difference in blood sampling time(35 min and 44 min sampling)in adults showed that there was no significant change in clearance regardless of the state of renal function. Correlation of the renal uptake rate obtained by the Bubeck method using a gamma camera could be expressed by a good straight regression line that passed around the origin of the coordinates. The results showed that, although the plasma clearance values obtained by the Bubeck method tended to be underestimated in the high clearance range compared with the values obtained by the Russell(1996)method, there was a very good correlation between the values obtained by the Bubeck method and renal uptake rate.
View full abstract
-
JUNJI SHIRAISHI, DAISAKU TATSUMI, HIROYUKI TSUSHIMA, AKANE UTSUNOMIYA, ...
Article type: Article
2001 Volume 57 Issue 7 Pages
860-867
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
A new method was investigated to estimate patient dose by the use of a digital imaging system such as a computed radiography system. With this method, the patient dose was assumed to be comparable to the absorbed dose at the directly irradiated region of a detector. Two approaches were examined based on the histrogram of image data and also the image indices of a digital imaging system such as S and L of a computed radiography system for estimating the absorbed dose. The correlation coefficient between the actual patient dose calculated from the exposure condition for chest radiography and the estimated patient dose by use of histogram data was very high(R=0.943). Estimated patient dose calculated by use of image indices S and L showed a relatively low correlation coefficient(R=0.789). Although this method provides a rough estimation, we believe that it can be useful as a simple and practical way to monitor patient dose during routine examinations using a digital imaging system.
View full abstract
-
Akiko Kano
Article type: Article
2001 Volume 57 Issue 7 Pages
868-
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
Article type: Appendix
2001 Volume 57 Issue 7 Pages
869-872
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
Article type: Appendix
2001 Volume 57 Issue 7 Pages
873-874
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
Article type: Appendix
2001 Volume 57 Issue 7 Pages
875-876
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
Article type: Appendix
2001 Volume 57 Issue 7 Pages
877-878
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
Article type: Appendix
2001 Volume 57 Issue 7 Pages
879-
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
RESTRICTED ACCESS
To protect personal information, PDF files cannot be viewed.
View full abstract
-
Article type: Appendix
2001 Volume 57 Issue 7 Pages
880-
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
Article type: Appendix
2001 Volume 57 Issue 7 Pages
881-882
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS
-
Article type: Cover
2001 Volume 57 Issue 7 Pages
Cover26-
Published: July 20, 2001
Released on J-STAGE: June 30, 2017
JOURNAL
FREE ACCESS