Nihon Hoshasen Gijutsu Gakkai zasshi最新文献_第5页

[Investigation of the Optimal Parameters for Block Sequential Regularized Expectation Maximization (BSREM) Reconstruction in Bone SPECT Using a Ring-type Semiconductor SPECT/CT]. [基于环形半导体SPECT/CT的骨SPECT块顺序正则化期望最大化（BSREM）重建的最优参数研究]。

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2025-01-01 DOI: 10.6009/jjrt.25-1560

Hayato Sato, Hayato Odagiri, Nao Yamaguchi, Hiroyasu Kodama, Takashi Takeuchi, Yoshitaka Tanaka, Kentaro Takanami, Akihito Usui, Tomohiro Kaneta

{"title":"[Investigation of the Optimal Parameters for Block Sequential Regularized Expectation Maximization (BSREM) Reconstruction in Bone SPECT Using a Ring-type Semiconductor SPECT/CT].","authors":"Hayato Sato, Hayato Odagiri, Nao Yamaguchi, Hiroyasu Kodama, Takashi Takeuchi, Yoshitaka Tanaka, Kentaro Takanami, Akihito Usui, Tomohiro Kaneta","doi":"10.6009/jjrt.25-1560","DOIUrl":"https://doi.org/10.6009/jjrt.25-1560","url":null,"abstract":"Purpose: This research aims to optimize the block sequential regularized expectation maximization (BSREM) reconstruction in bone single photon emission computed tomography (SPECT) images using a ring-type SPECT/computed tomography (CT) system in terms of image quality and accuracy of quantitative evaluation.Methods: SPECT images were acquired using a ring-type SPECT/CT and from a SIM2 bone phantom containing a 99m-Tc solution. BSREM parameters were assessed with coefficient of variation (CV), recovery coefficient (RC), contrast noise ratio (CNR), standardized uptake value max (SUVmax), and its root mean square error (RMSESUVmax). Clinical images were reconstructed, and the reconstructions were evaluated as superior based on phantom results.Results: Increasing γ led to higher RC and CV, while increasing β lowered these values. CNR showed no consistent trend. In terms of quantitative evaluation, γ value 5.0, β values 0.3-0.9, and γ value 10, βvalues 0.3-0.9 resulted in lower RMSESUVmax compared to Anger type. Based on the phantom experiment, γ value 5.0, β values 0.5-0.9, and γ value 10, β values 0.7-0.9 were evaluated as superior. Clinical images under these reconstructions, determined from the phantom experiments, with γ value 5.0, β value 0.9, showed the smoothest of normal bone and the clearest separation of neighboring tumors.Conclusion: As reconstruction parameters for BSREM reconstruction in bone SPECT on a ring-type semiconductor SPECT/CT system, a γ value of 5.0 and a β value of 0.9 were considered suitable for image quality and quantitative evaluation.","PeriodicalId":74309,"journal":{"name":"Nihon Hoshasen Gijutsu Gakkai zasshi","volume":"81 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144509865","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

[Evaluation of Exposure Dose Reduction Effect for Cone-beam Computed Tomography with Bismuth Sheet in Image-guided Radiation Therapy of Prostate Cancer]. [图像引导前列腺癌放射治疗中锥形束ct加铋片照射剂量降低效果评价]。

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2025-01-01 DOI: 10.6009/jjrt.25-1531

Tatsuya Yoshida, Koji Sasaki, Tomoki Hayakawa, Toshiyuki Kawadai, Takako Shibasaki, Yoshiyuki Kawasaki

{"title":"[Evaluation of Exposure Dose Reduction Effect for Cone-beam Computed Tomography with Bismuth Sheet in Image-guided Radiation Therapy of Prostate Cancer].","authors":"Tatsuya Yoshida, Koji Sasaki, Tomoki Hayakawa, Toshiyuki Kawadai, Takako Shibasaki, Yoshiyuki Kawasaki","doi":"10.6009/jjrt.25-1531","DOIUrl":"10.6009/jjrt.25-1531","url":null,"abstract":"Purpose: Image-guided radiation therapy using cone-beam computed tomography (CBCT) for prostate cancer is problematic due to the increasing exposure dose at each treatment session. This study aimed to evaluate the effect of exposure dose reduction using bismuth sheets for pelvic CBCT.Methods: Using a radiophotoluminescence dosimeter (GD-352M) and CBCT imaging conditions with three X-ray tube rotation angles (292°-88°, 92°-248°, and 92°-88°), absorbed doses were measured in the rectum, anterior and posterior bladder walls, right and left pelvic subcutaneous at 5 cm superior the prostate center of the pelvic phantom and in a testis. Next, the same measurements were performed when these measurement points were covered with a bismuth sheet.Results: The absorbed doses at 92°-248° with the bismuth sheets were reduced by 31.3% from 16.3±0.2 mGy to 11.2±0.2 mGy for the rectum and by 57.1% from 45.0±2.7 mGy to 19.3±1.0 mGy for the testis, which were the lowest among the imaging conditions. Although the anterior and posterior bladder walls were the highest dose at 48.7±11.5 and 20.2±0.4 mGy, the high reduction rates of 42.0% and 36.9%, respectively.Conclusion: From the viewpoint of the exposure risk to the bladder, rectum, and testis, using bismuth sheets and the X-ray tube rotation angle of 92°-248° effectively reduced the exposure dose.","PeriodicalId":74309,"journal":{"name":"Nihon Hoshasen Gijutsu Gakkai zasshi","volume":"81 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143538192","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

[Image Quality Assessment of Non-contrast Brain Computed Tomography Using High-pitch Double Spiral Scan: A Basic Evaluation Using Phantom]. [使用高音高双螺旋扫描的非对比脑计算机断层成像质量评估：基于Phantom的基本评估]。

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2025-01-01 DOI: 10.6009/jjrt.25-1499

Yuichiro Sato, Tomomi Ohmura, Shun Muramatsu, Yuki Shinohara, Fumiaki Sasaki, Kazunori Matsumoto, Kouya Nakaizumi, Mamoru Kato

{"title":"[Image Quality Assessment of Non-contrast Brain Computed Tomography Using High-pitch Double Spiral Scan: A Basic Evaluation Using Phantom].","authors":"Yuichiro Sato, Tomomi Ohmura, Shun Muramatsu, Yuki Shinohara, Fumiaki Sasaki, Kazunori Matsumoto, Kouya Nakaizumi, Mamoru Kato","doi":"10.6009/jjrt.25-1499","DOIUrl":"https://doi.org/10.6009/jjrt.25-1499","url":null,"abstract":"Purpose: Motion artifacts likely occur in patients with acute intracerebral hemorrhage (ICH). This study aimed to validate the image quality characteristics of non-contrast brain computed tomography (CT) with high-speed imaging technology, named Flash spiral (FS) (Siemens Healthineers, Erlangen, Germany). We verified the differences in CT values using a phantom that simulated hematoma.Methods: A dual-source CT scanner (SOMATOM Drive; Siemens Healthineers) was used to obtain reference and FS images of a Catphan700 phantom (The Phantom Laboratory, Greenwich, NY, USA). The CT values were measured in the hematoma-simulated acrylic module and urethane within the phantom. The noise power spectrum (NPS), task transfer function (TTF), and system performance function (SPF) between reference and FS images were obtained to compare image quality in each scan.Results: Compared with the phantom's reference and FS images, no significant differences were observed in the CT values between the samples simulating hematoma and their surrounding areas. The NPS showed lower values in the FS images than the reference images at spatial frequencies above approximately 0.4 cycles/mm, while the peak frequencies were nearly equivalent. The 10% TTF values were almost the same between both images. The SPF values were also equivalent between the two images at spatial frequencies above approximately 0.5 cycles/mm.Conclusion: In the phantom experiment, the 10% TTF values of the FS images were comparable to those of the reference images, indicating similar resolution in the high spatial frequency domain. FS is expected to expand the applicability for detecting cerebral hemorrhage in patients with significant body movement, where detection is challenging under standard conditions.","PeriodicalId":74309,"journal":{"name":"Nihon Hoshasen Gijutsu Gakkai zasshi","volume":"81 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144082625","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

[Comparative Study of Surface Conformity of Flexible Boluses Composed of Different Materials]. [不同材料柔性弹体表面一致性的比较研究]。

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2025-01-01 DOI: 10.6009/jjrt.25-1583

Hideharu Miura, Kenji Kanemoto, Toshiya Okazue, Shuichi Ozawa, Masahiro Kenjo

{"title":"[Comparative Study of Surface Conformity of Flexible Boluses Composed of Different Materials].","authors":"Hideharu Miura, Kenji Kanemoto, Toshiya Okazue, Shuichi Ozawa, Masahiro Kenjo","doi":"10.6009/jjrt.25-1583","DOIUrl":"https://doi.org/10.6009/jjrt.25-1583","url":null,"abstract":"Purpose: The purpose of this study was to compare the surface conformity of Clearfit Bolus II (Clearfit2) (Fujidenolo, Aichi) and Clearfit Bolus (Clearfit1) (Fujidenolo) using an anthropomorphic phantom.Methods: Clearfit1 and Clearfit2 boluses (5 mm thick) were placed in three anatomical regions of the anthropomorphic phantom: nose, breast, and abdomen, and CT scans were performed. Digital Imaging and Communications in Medicine (DICOM) structural data were used to measure the air gap between the bolus and the surface of the phantom. The surface conformity area ratio at the threshold (1-5 mm) was calculated. Statistical analysis was performed using the Mann-Whitney U test.Results: Clearfit2 had significantly reduced air gaps compared to Clearfit1: 2.9±2.0 mm in the nose, 1.8±2.1 mm in the breasts, and 0.1±0.1 mm in the abdomen, which were lower than Clearfit1's 5.8±2.9 mm, 11.4±8.4 mm, and 2.2±2.1 mm, respectively (p<0.001). In the abdominal region, Clearfit2 achieved near-perfect surface conformity with over 99% of the surface showing gaps ≤1 mm.Conclusion: We demonstrated that Clearfit2 significantly improves the surface conformity by reducing air gaps between the bolus and the phantom surface compared to Clearfit1.","PeriodicalId":74309,"journal":{"name":"Nihon Hoshasen Gijutsu Gakkai zasshi","volume":"81 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144651421","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

[Implementation Report: Attempt for a Decision of Priorities in Measures to Prevent Recurrence of Low-level Incidents Using Priority Monitoring Score]. [实施报告：利用优先级监测评分确定预防低级别事件再次发生措施的优先级的尝试]。

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2025-01-01 DOI: 10.6009/jjrt.25-1534

Makoto Sasaki, Isao Yamaguchi, Yoshihiro Kitoh, Tsuyoshi Ueyama, Ryuhei Iwaki, Naomi Nishio, Tetsuo Kida, Koji Koizumi, Hidemichi Kawata

{"title":"[Implementation Report: Attempt for a Decision of Priorities in Measures to Prevent Recurrence of Low-level Incidents Using Priority Monitoring Score].","authors":"Makoto Sasaki, Isao Yamaguchi, Yoshihiro Kitoh, Tsuyoshi Ueyama, Ryuhei Iwaki, Naomi Nishio, Tetsuo Kida, Koji Koizumi, Hidemichi Kawata","doi":"10.6009/jjrt.25-1534","DOIUrl":"https://doi.org/10.6009/jjrt.25-1534","url":null,"abstract":"Purpose: The aim of this study was to attempt to make a decision on priorities in measures to prevent recurrence of previously reported low-level incidents using the priority monitoring score.Methods: A survey of the low-level incidents reported over the past 5 years in the department of radiation therapy was conducted among 7 radiological technologists. From the results of the survey, the priority monitoring score was calculated by multiplying each score of the potential incident level, the occurrence frequency, and the detectability. Additionally, the relationship between the priority monitoring score and each factor was investigated.Results: From the results of a survey of 67 low-level incidents, the mean+standard deviation (23.1) of the priority monitoring score was set as the threshold for a decision of priorities. The strongest correlation was observed between the priority monitoring score and the potential incident level (a correlation coefficient, r=0.74).Conclusion: It is suggested that the possibility of prioritizing the decision of low-level incidents that require measures to prevent recurrence be considered by setting the threshold for the priority monitoring score. On the other hand, the reporting requirements and the level classification for incidents vary among facilities. Therefore, the threshold for the decision of priorities needs to be considered in each facility.","PeriodicalId":74309,"journal":{"name":"Nihon Hoshasen Gijutsu Gakkai zasshi","volume":"81 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144651437","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

[6. Commissioning and Dosimetry Standards for 0.35 Tesla MRI Linac]. (6。0.35特斯拉MRI直线加速器的调试和剂量学标准[j]。

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2025-01-01 DOI: 10.6009/jjrt.25-0200

Yu Kumazaki

引用次数: 0

[Dr. Taizo Sanada]. [医生Taizo Sanada]。

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2025-01-01 DOI: 10.6009/jjrt.25-0201

Yoshinori Tanabe

引用次数: 0

["Radiology for Everyone"-Join Us in Shaping the Future!-An Invitation to the 81st Annual Meeting of the Japanese Society of Radiological Technology (JSRT) in Yokohama]. “每个人的放射学”——与我们一起共创未来！-邀请参加在横滨举行的日本放射技术学会（JSRT）第81届年会上]。

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2025-01-01 DOI: 10.6009/jjrt.25-0300

Hideyuki Iwanaga

引用次数: 0

[Comparison of the Impact of Deep Learning Techniques on Low-noise Head CT Images]. [深度学习技术对低噪声头部CT图像影响的比较]。

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2025-01-01 DOI: 10.6009/jjrt.25-1537

Takuro Tahara, Seigo Yoshida

{"title":"[Comparison of the Impact of Deep Learning Techniques on Low-noise Head CT Images].","authors":"Takuro Tahara, Seigo Yoshida","doi":"10.6009/jjrt.25-1537","DOIUrl":"10.6009/jjrt.25-1537","url":null,"abstract":"Purpose: This study aims to compare the effects of two types of deep learning (DL) techniques on brain CT values, image noise content, and contrast-to-noise ratio (CNR) between white and gray matter in low-noise head CT images, along with adaptive iterative dose reduction 3D (AIDR 3D).Methods: Twenty-one normal patients with no abnormal findings who underwent head CT for identification of acute illness were included in the study. DL techniques used were Advanced intelligent Clear-IQ Engine (AiCE, Canon Medical systems, Tochigi, Japan) and PixelShine (FUJIFILM Medical, Tokyo, Japan). We performed CT value measurements of 26 cerebrum regions, image noise measurements, and CNR calculations. We also conducted a visual assessment of image noise and white matter-gray matter contrast on a 5-point scale.Results: Image noise significantly decreased with DL techniques. CT values changed significantly with AiCE. CNR for white matter-gray matter was the highest with PixelShine (P<0.01). The visual assessment of white matter-gray matter contrast was the highest for PixelShine and the lowest for AiCE (P<0.01).Conclusion: While DL techniques reduce image noise, there are differences in CT values and visual impression, especially white matter-gray matter contrast, so care should be taken when using it.","PeriodicalId":74309,"journal":{"name":"Nihon Hoshasen Gijutsu Gakkai zasshi","volume":"81 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143775036","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

[2. Radiopharmaceuticals for Targeted Radiotherapy]. (2。靶向放疗用放射性药物[m]。

Nihon Hoshasen Gijutsu Gakkai zasshi Pub Date : 2025-01-01 DOI: 10.6009/jjrt.25-0501

Koki Hasegawa

引用次数: 0