Nihon Hoshasen Gijutsu Gakkai zasshi最新文献_第10页

[Segmentation of Mass in Mammogram Using Gaze Search Patterns]. [利用目光搜索模式分割乳房 X 光照片中的肿块]。

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2024-05-20 Epub Date: 2024-03-14 DOI: 10.6009/jjrt.2024-1438

Eiichiro Okumura, Hideki Kato, Tsuyoshi Honmoto, Nobutada Suzuki, Erika Okumura, Takuji Higashigawa, Shigemi Kitamura, Jiro Ando, Takayuki Ishida

{"title":"[Segmentation of Mass in Mammogram Using Gaze Search Patterns].","authors":"Eiichiro Okumura, Hideki Kato, Tsuyoshi Honmoto, Nobutada Suzuki, Erika Okumura, Takuji Higashigawa, Shigemi Kitamura, Jiro Ando, Takayuki Ishida","doi":"10.6009/jjrt.2024-1438","DOIUrl":"10.6009/jjrt.2024-1438","url":null,"abstract":"Purpose: It is very difficult for a radiologist to correctly detect small lesions and lesions hidden on dense breast tissue on a mammogram. Therefore, recently, computer-aided detection (CAD) systems have been widely used to assist radiologists in interpreting images. Thus, in this study, we aimed to segment mass on the mammogram with high accuracy by using focus images obtained from an eye-tracking device.Methods: We obtained focus images for two mammography expert radiologists and 19 mammography technologists on 8 abnormal and 8 normal mammograms published by the DDSM. Next, the auto-encoder, Pix2Pix, and UNIT learned the relationship between the actual mammogram and the focus image, and generated the focus image for the unknown mammogram. Finally, we segmented regions of mass on mammogram using the U-Net for each focus image generated by the auto-encoder, Pix2Pix, and UNIT.Results: The dice coefficient in the UNIT was 0.64±0.14. The dice coefficient in the UNIT was higher than that in the auto-encoder and Pix2Pix, and there was a statistically significant difference (p<0.05). The dice coefficient of the proposed method, which combines the focus images generated by the UNIT and the original mammogram, was 0.66±0.15, which is equivalent to the method using the original mammogram.Conclusion: In the future, it will be necessary to increase the number of cases and further improve the segmentation.","PeriodicalId":74309,"journal":{"name":"Nihon Hoshasen Gijutsu Gakkai zasshi","volume":" ","pages":"487-498"},"PeriodicalIF":0.0,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140121541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

[Noise Nonuniformity Dependency on Exposure Settings in Computed Tomography]. [计算机断层扫描中噪声不均匀性与曝光设置的关系]。

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2024-05-20 Epub Date: 2024-03-15 DOI: 10.6009/jjrt.2024-1417

Mitsuo Narita, Masayuki Nishiki

{"title":"[Noise Nonuniformity Dependency on Exposure Settings in Computed Tomography].","authors":"Mitsuo Narita, Masayuki Nishiki","doi":"10.6009/jjrt.2024-1417","DOIUrl":"10.6009/jjrt.2024-1417","url":null,"abstract":"Purpose: In X-ray computed tomography (CT), noise distribution within images is nonuniform and thought to vary with imaging conditions. This study aimed to evaluate noise nonuniformity by altering specific imaging conditions, such as tube voltage, bow-tie filter (BTF), and phantom size.Methods: Using four tube voltages (80, 100, 120, and 135 kV), two BTF types (L and M), and circular water phantoms with diameters of 240, 320, and 400 mm, we employed filtered back projection (FBP) for reconstruction. Noise nonuniformity was assessed by defining six regions of interest (ROI) from the image center to the periphery, and the noise nonuniformity index (NNI) was calculated based on the standard deviation (SD) values within these ROIs.Results: Results showed consistently larger noise SD values in the central region compared to the peripheral region under all imaging conditions, with the maximum NNI reaching 32.1%. Variations in NNI were observed, reaching up to 5.5 points for tube voltage, 7.8 points for BTF, and 8.2 points for phantom size.Conclusion: In conclusion, our quantitative assessment revealed moderate dependence of noise nonuniformity on imaging conditions in CT images.","PeriodicalId":74309,"journal":{"name":"Nihon Hoshasen Gijutsu Gakkai zasshi","volume":" ","pages":"530-538"},"PeriodicalIF":0.0,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140144817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

[Reduction of Motion Artifacts in Liver MRI Using Deep Learning with High-pass Filtering]. [利用深度学习和高通滤波器减少肝脏磁共振成像中的运动伪影]。

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2024-05-20 Epub Date: 2024-03-11 DOI: 10.6009/jjrt.2024-1408

Motohira Mio, Nariaki Tabata, Tatsuo Toyofuku, Hironori Nakamura

{"title":"[Reduction of Motion Artifacts in Liver MRI Using Deep Learning with High-pass Filtering].","authors":"Motohira Mio, Nariaki Tabata, Tatsuo Toyofuku, Hironori Nakamura","doi":"10.6009/jjrt.2024-1408","DOIUrl":"10.6009/jjrt.2024-1408","url":null,"abstract":"Purpose: To investigate whether deep learning with high-pass filtering can be used to effectively reduce motion artifacts in magnetic resonance (MR) images of the liver.Methods: The subjects were 69 patients who underwent liver MR examination at our hospital. Simulated motion artifact images (SMAIs) were created from non-artifact images (NAIs) and used for deep learning. Structural similarity index measure (SSIM) and contrast ratio (CR) were used to verify the effect of reducing motion artifacts in motion artifact reduction image (MARI) output from the obtained deep learning model. In the visual assessment, reduction of motion artifacts and image sharpness were evaluated between motion artifact images (MAIs) and MARIs.Results: The SSIM values were 0.882 on the MARIs and 0.869 on the SMAIs. There was no statistically significant difference in CR between NAIs and MARIs. The visual assessment showed that MARIs had reduced motion artifacts and improved sharpness compared to MAIs.Conclusion: The learning model in this study is indicated to be reduced motion artifacts without decreasing the sharpness of liver MR images.","PeriodicalId":74309,"journal":{"name":"Nihon Hoshasen Gijutsu Gakkai zasshi","volume":" ","pages":"510-518"},"PeriodicalIF":0.0,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140095339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

[Questionnaire Survey of Radiation Protection Education in Hospitals]. [医院辐射防护教育问卷调查]。

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2024-04-23 DOI: 10.6009/jjrt.2024-1394

Shogo Horita, Hiromi Sakuda, Takayuki Igarashi, Hideyuki Iwanaga, Takao Ichida, Yasuo Okuda, Junji Shiraishi, Hisako Ueno, Katsumasa Ota, Tomoko Kusama

{"title":"[Questionnaire Survey of Radiation Protection Education in Hospitals].","authors":"Shogo Horita, Hiromi Sakuda, Takayuki Igarashi, Hideyuki Iwanaga, Takao Ichida, Yasuo Okuda, Junji Shiraishi, Hisako Ueno, Katsumasa Ota, Tomoko Kusama","doi":"10.6009/jjrt.2024-1394","DOIUrl":"https://doi.org/10.6009/jjrt.2024-1394","url":null,"abstract":"PURPOSE\u0000The present study aimed to investigate the current situation of radiation protection education for designated radiation workers in hospitals.\u0000\u0000\u0000METHODS\u0000A web-based questionnaire survey was conducted at 1,883 hospitals nationwide with 200 or more beds.\u0000\u0000\u0000RESULTS\u0000Responses from 186 hospitals were included in the analysis. Seven hospitals (6.7%) regulated by the Act on the Regulation of Radioisotopes and six hospitals (7.4%) regulated by only the Ordinance on Prevention of Ionizing Radiation Hazards did not implement radiation protection education. In approximately 6% of the hospitals, designated radiation workers-including physicians, nurses, and radiological technologist-did not attend the education program. The education program attendance rate of physicians was lower than that of nurses. In more than 90% of the hospitals, the frequency of the periodical education program was once every year and lecture time spanned one or less than one hour. The topics of lecture in more than 90% of the hospitals were health effects of radiation and methods of radiation protection for occupational exposure. The radiological technologist was the instructor of the education program in approximately 70% of the hospitals.\u0000\u0000\u0000CONCLUSION\u0000The implementation of radiation protection for designated radiation workers varied from hospital to hospital, and some hospitals did not comply with laws and regulations. Effective and efficient radiation protection education models should be implemented in hospitals.","PeriodicalId":74309,"journal":{"name":"Nihon Hoshasen Gijutsu Gakkai zasshi","volume":"8 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140671633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

[7. Calculation Algorithm for Electron Beam Therapy]. [电子束疗法的计算算法]。

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2024-04-20 DOI: 10.6009/jjrt.2024-2345

Yoshio Iwai

引用次数: 0

[About Japanese Journal of Radiological Technology!] [关于《日本放射技术杂志》！]

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2024-04-20 DOI: 10.6009/jjrt.2024-2346

Koichi Chida

引用次数: 0

[Radiation Dose Reduction through the Optimization of Mask Images in Cerebral Angiography]. [通过优化脑血管造影中的掩膜图像减少辐射剂量]。

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2024-04-20 Epub Date: 2024-03-19 DOI: 10.6009/jjrt.2024-1386

Kota Hachiya, Koichi Chida, Yoshikazu Matsuda

{"title":"[Radiation Dose Reduction through the Optimization of Mask Images in Cerebral Angiography].","authors":"Kota Hachiya, Koichi Chida, Yoshikazu Matsuda","doi":"10.6009/jjrt.2024-1386","DOIUrl":"10.6009/jjrt.2024-1386","url":null,"abstract":"Purpose: To verify the effectiveness of optimizing the number of mask images in DSA for radiation dose reduction during cerebral angiography.Methods: A total of 60 angiography sessions in 2 times for 30 patients performed by the same operator were included in this study. In order to compare the effects of optimization to change the injection delay time of DSA from 1 s to the shortest possible time, the number of mask images, the number of imaging frames, and radiation doses between sessions were compared and analyzed retrospectively.Results: In one DSA run, the number of mask images was decreased from 6 (5-7) to 3 (2-3) frames (p<0.01)/57.1% (median [IQR]/reduction rate), the number of imaging frames was decreased from 34 (32-36) to 32 (29-34) frames (p<0.01)/7.9%, and the radiation dose was decreased from 33 (23-47) to 30 (21-40) mGy (p<0.01)/8.3%. In magnification angiography, the reductions rate was significantly increased. In one angiography session, the number of mask images was decreased from 45 (35-72) to 19 (16-34) frames (p<0.01)/54.6%, the number of imaging frames was decreased from 242 (199-385) to 211 (181-346) frames (p<0.01)/8.3%, the radiation dose of DSA was decreased from 295 (190-341) to 242 (167-305) mGy (p<0.01)/11.6%, and the total radiation dose was decreased from 369 (259-418) to 328 (248-394) mGy (p<0.01)/7.5%.Conclusion: Using the shortest possible injection delay time for the number of mask image optimization was an effective radiation dose reduction method.","PeriodicalId":74309,"journal":{"name":"Nihon Hoshasen Gijutsu Gakkai zasshi","volume":" ","pages":"365-373"},"PeriodicalIF":0.0,"publicationDate":"2024-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139934579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

[Participation/Dispatch Reports on the 51st Autumn Meeting]. [第 51 次秋季会议与会情况/派遣报告]。

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2024-04-20 DOI: 10.6009/jjrt.2024-2330

Naho Irie, Takumi Morishita, Yuto Nakaya, Rune Tsuneyoshi, Yuki Okabe, Ayano Akisawa, Rinko Yamamoto, Mio Nakamura, Kota Sasaki, Miku Ohata, Akari Mashiko, Chika Tatsugae, Masafumi Akanuma, Eiichi Maehara

引用次数: 0

[Accuracy Verification for Slice Sensitivity Profile Measurement Method by Averaging the Multiple Tilted Wires in Computed Tomography Image]. [通过平均计算机断层扫描图像中的多条倾斜导线，验证切片灵敏度轮廓测量方法的准确性]。

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2024-04-20 Epub Date: 2024-03-07 DOI: 10.6009/jjrt.2024-1427

Takeshi Fukaya, Katsuhiko Murakami, Masaki Saito, Toshihiko Katakura

{"title":"[Accuracy Verification for Slice Sensitivity Profile Measurement Method by Averaging the Multiple Tilted Wires in Computed Tomography Image].","authors":"Takeshi Fukaya, Katsuhiko Murakami, Masaki Saito, Toshihiko Katakura","doi":"10.6009/jjrt.2024-1427","DOIUrl":"10.6009/jjrt.2024-1427","url":null,"abstract":"Purpose: Several studies present the unsuitability of the tilted-wire method for slice sensitivity profile (SSP) in helical scan. We compared the accuracy for SSP by the tilted-wire averaging method using multiple wire profiles and by the conventional micro-coin method.Methods: A micro-coin phantom positioned at the center or the off-center was scanned using a 64-detector row CT scanner in different positions where an X-ray tube starts scanning. In the same way, tilted-wire averaging phantoms, approximately 70 mm in diameter, in the shape of a donut, 8 wires tilted from the circumference toward the center, were scanned. Images were reconstructed with a slice thickness of 0.5 mm.Results: The relative errors of full width at half maximum (FWHM) by the tilted-wire averaging method were -0.015 mm to -0.004 mm (-1.98% to -0.56%) at the center compared to those by the micro-coin method, and it is almost the same value regardless of the number of wires. Relative errors were 0.001 mm to 0.029 mm (0.11% to 3.74%) at the upper 8 cm from the center, and 0.014 mm to 0.078 mm (1.86% to 10.25%) at the upper 16 cm, and the value of relative errors increased as it got farther from the center and as the number of wires went fewer.Conclusion: This study indicated that accurate measurement of SSP may be achieved by using 4 (arranged every 90 degrees) or more averaging wires.","PeriodicalId":74309,"journal":{"name":"Nihon Hoshasen Gijutsu Gakkai zasshi","volume":" ","pages":"390-402"},"PeriodicalIF":0.0,"publicationDate":"2024-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140051203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

[Construction of a Temporary Radiological Image Viewing Network for Large-scale Disasters]. [构建大规模灾害临时辐射图像查看网络]。

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2024-04-20 Epub Date: 2024-02-26 DOI: 10.6009/jjrt.2024-1414

Shigeyoshi Wakamatsu, Yasumasa Saigo, Yoshifumi Oku, Takahiro Yamashita

{"title":"[Construction of a Temporary Radiological Image Viewing Network for Large-scale Disasters].","authors":"Shigeyoshi Wakamatsu, Yasumasa Saigo, Yoshifumi Oku, Takahiro Yamashita","doi":"10.6009/jjrt.2024-1414","DOIUrl":"10.6009/jjrt.2024-1414","url":null,"abstract":"The Ministry of Health, Labor and Welfare mandated the creation of the business continuity plan (BCP) for disaster key hospitals on March 31, 2017. Supposing the hospital information system (HIS) failure occurred, the picture archiving and communication system (PACS) also suffers obstacles, we assumed building a new network was necessary for radiological examination images. The purpose of this study was to investigate whether building a new network for radiological examination images is necessary in an emergency. Using wireless fidelity (Wi-Fi), the new network consisting of one image server and two tablet terminals A and B was constructed. The study measured the portable image transfer time for various stages of the network. The results were as follows: Transfer time from the mobile X-ray unit to the image server was 4.12±0.86 s, that from the image server to the tablet device A was 5.14±0.71 s, and that from the image server to the tablet device B was 7.32±1.66 s. Therefore, the new network configuration can provide a reliable means of accessing radiological images during emergency situations when the HIS and PACS may experience obstacles or failures.","PeriodicalId":74309,"journal":{"name":"Nihon Hoshasen Gijutsu Gakkai zasshi","volume":" ","pages":"385-389"},"PeriodicalIF":0.0,"publicationDate":"2024-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139974905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0