著者

白石 順二 桂川 茂彦 土井 邦雄 池添 潤平 松本 常男 小林 健 小松 研一 藤田 広志 松井 美楯 小寺 吉衛

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.3, pp.370-375, 2000-03-20

被引用文献数

4

著者

白石 順二 宇都宮 あかね

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.53, no.6, pp.691-698, 1997-06-20 (Released:2017-06-29)

参考文献数

6

被引用文献数

15 11

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Several methods of testing statistically significant differences were used to evaluate the usefulness of one diagnostic imaging system compared with any other imaging system using ROC analysis. Comparison of usefulness between conventional methods such as the two-tailed paired t-test and 95% confidence intervals, and Jackknife method for ROC analysis, which was reported a few years ago, were investigated with actual two experimental results from ROC studies. From the testing results, it was considered that conventional methods reguire large numbers of readers in order to improve the reliability of statistically significant test differenxes between the two imaging systems. When determining differences between two kinds of imaging modalities, the use of the Jackknife method was better than conventional methods in terms of the reliability of test results, because conventional methods do not consider variances between readers and case samples.

著者

白石 順二 花岡 信子 宇都宮 あかね 上田 容子 津田 和良

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.53, no.1, pp.19-24, 1997-01-20 (Released:2017-06-29)

参考文献数

4

被引用文献数

2 1

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The relationship between gantry angle and the interval length of the scanning plane in computed tomography(CT)was studied with a simple geometrical calculation and the evaluation of clinical images obtained with a human phantom. The change in patient dose was also evaluated under various conditions of gantry angle. When the same table feeding distance was used, it was theoretically and experimentally demonstrated that the interval length of the scanning plane was significantly decreased as the gantry angle increased(e.g.about 10% at twenty-five degrees). Integrated patient dose during the sequence could be changed by various combinations of gantry angle and table feeding distance, and was decreased by setting an optimal interval length of scanning plane according to the gantry angle. We concluded that gantry angle had obvious effects on the interval length of the scanning plane and patient dose, and the new method of increasing the table feeding distance according to the gantry angle might be useful for the improvement of image reproduction and the reduction of patient dose.

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.72, no.5, pp.I, 2016

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

長野 宣道 松尾 孝美 伊藤 隆志 友成 健一朗 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.68, no.11, pp.1474-1485, 2012-11-20 (Released:2012-11-21)

参考文献数

28

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We proposed a method for a computer-aided diagnosis system that distinguishes between benign and malignant lesions in gastrointestinal digital radiography. To begin with, the level set method was applied in order to extract a tumor region from the image which was smoothed by the bilateral filter. Next, we selected four image features with the large SN ratio among various image features obtained from a tumor region using the Mahalanobis-Taguchi method, which has been employed mainly in quality engineering. The selected four image features—circularity, irregularity, size, and perimeter—were used as input data for the artificial neural network, which was employed for distinction between benign and malignant lesions. By using 43 regions of interest cropped from the 43 clinical cases, the area under the ROC curve (AUC) of diagnostic accuracy for the classification obtained with this proposed method was 0.970, whereas the average AUC obtained with 7 human observers (3 radiologists and 4 radiological technologist) was 0.941.

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.63, no.10, pp.1200-1207, 2007-10-20 (Released:2008-01-10)

参考文献数

8

被引用文献数

9 8

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(抄録はありません)

著者

白石 順二 山崎 勝 田中 克尚 岸本 健治 畑川 政勝

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.10, pp.1726-1734, 1994-10-01

被引用文献数

7

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In the past years, receiver operating characteristic (ROC) studies that has been used in medical imaging system have involved data collected on a discrete confidence-rating scale with five categories, though in principle ROC studies which are called method for continuously-distributed test results can be conducted with continuous scale. In this study, we investigate the advantage of this new rating method. Advantages were obtained from our experiments that used both discrete and continuous rating scale with same sample sets. From the results of ROC analysis using the CR mammography with simulated mamma phantom, the method for continuously-distributed test results performs identical estimation of area under the ROC curve (Az) compared with the discrete confidence-rating method, but performs good (1/3) standard deviation of Az between readers. When the range of Az lies 0.65-0.70 which are "difficult" performance of ROC experiment, we concluded that the method for continuously-distributed test results has the advantages of good statistical power and reliability of results compared with the discrete confidencerating method.

著者

藤田 広志 志村 一男 白石 順二 西原 貞光 東田 善治 山下 一也

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.49, no.9, pp.1685-1703, 1993-09-01

被引用文献数

16

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This professional Committee's report describes the results of the activities made by the Task Group for ROC Analysis in Digital Radiography in 1992. Beginning with interpreting the basis of ROC analysis, explanation is made of ROC curve fitting and ROC curve's statistically significant difference test. Next, explanation is made of LROC and FROC with the development from FROC to AFROC, as well as "continuous confidence method" (provisional designation) as the recent progress in ROC analysis, including its brief experimental results. Finally, report is made in the actual condition of ROC analysis in DR system and the investigational results of ROC analysis of CAD.