Radiological Physics and Technology最新文献_第10页

Development of an open project rectangular collimator for use with intraoral dental X-ray unit. 开发用于口内牙科 X 射线装置的开放式矩形准直器。

IF 1.6

Radiological Physics and Technology Pub Date : 2024-03-01 Epub Date: 2024-01-24 DOI: 10.1007/s12194-023-00772-9

Marina C Poletto, Eduardo Thomazi, Janete E Zorzi, Thiago O Gamba, Cláudio A Perottoni

引用次数: 0

Evaluation of attenuation correction method for head holder in brain perfusion single-photon emission computed tomography. 评估脑灌注单光子发射计算机断层扫描中头部支架的衰减校正方法。

IF 1.6

Radiological Physics and Technology Pub Date : 2024-03-01 Epub Date: 2024-02-09 DOI: 10.1007/s12194-024-00778-x

Masahiro Nakashima, Yuta Yamazaki

引用次数: 0

Improving the depiction of small intracranial vessels in head computed tomography angiography: a comparative analysis of deep learning reconstruction and hybrid iterative reconstruction. 改善头部计算机断层扫描血管造影术中颅内小血管的描绘：深度学习重建和混合迭代重建的比较分析。

IF 1.6

Radiological Physics and Technology Pub Date : 2024-03-01 Epub Date: 2023-10-28 DOI: 10.1007/s12194-023-00749-8

Makoto Ozaki, Shota Ichikawa, Masaaki Fukunaga, Hiroyuki Yamamoto

引用次数: 0

Preclinical magnetic resonance imaging and spectroscopy in the fields of radiological technology, medical physics, and radiology. 放射技术、医学物理和放射学领域的临床前磁共振成像和光谱学。

IF 1.6

Radiological Physics and Technology Pub Date : 2024-03-01 Epub Date: 2024-02-14 DOI: 10.1007/s12194-024-00785-y

Shigeyoshi Saito, Junpei Ueda

{"title":"Preclinical magnetic resonance imaging and spectroscopy in the fields of radiological technology, medical physics, and radiology.","authors":"Shigeyoshi Saito, Junpei Ueda","doi":"10.1007/s12194-024-00785-y","DOIUrl":"10.1007/s12194-024-00785-y","url":null,"abstract":"Magnetic resonance imaging (MRI) is an indispensable diagnostic imaging technique used in the clinical setting. MRI is advantageous over X-ray and computed tomography (CT), because the contrast provided depends on differences in the density of various organ tissues. In addition to MRI systems in hospitals, more than 100 systems are used for research purposes in Japan in various fields, including basic scientific research, molecular and clinical investigations, and life science research, such as drug discovery, veterinary medicine, and food testing. For many years, additional preclinical imaging studies have been conducted in basic research in the fields of radiation technology, medical physics, and radiology. The preclinical MRI research includes studies using small-bore and whole-body MRI systems. In this review, we focus on the animal study using small-bore MRI systems as \"preclinical MRI\". The preclinical MRI can be used to elucidate the pathophysiology of diseases and for translational research. This review will provide an overview of previous preclinical MRI studies such as brain, heart, and liver disease assessments. Also, we provide an overview of the utility of preclinical MRI studies in radiological physics and technology.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":"47-59"},"PeriodicalIF":1.6,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10901953/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139730721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Verification of image quality improvement of low-count bone scintigraphy using deep learning. 利用深度学习验证低计数骨闪烁成像的图像质量改进。

IF 1.6

Radiological Physics and Technology Pub Date : 2024-03-01 Epub Date: 2024-02-10 DOI: 10.1007/s12194-023-00776-5

Taisuke Murata, Takuma Hashimoto, Masahisa Onoguchi, Takayuki Shibutani, Takashi Iimori, Koichi Sawada, Tetsuro Umezawa, Yoshitada Masuda, Takashi Uno

{"title":"Verification of image quality improvement of low-count bone scintigraphy using deep learning.","authors":"Taisuke Murata, Takuma Hashimoto, Masahisa Onoguchi, Takayuki Shibutani, Takashi Iimori, Koichi Sawada, Tetsuro Umezawa, Yoshitada Masuda, Takashi Uno","doi":"10.1007/s12194-023-00776-5","DOIUrl":"10.1007/s12194-023-00776-5","url":null,"abstract":"To improve image quality for low-count bone scintigraphy using deep learning and evaluate their clinical applicability. Six hundred patients (training, 500; validation, 50; evaluation, 50) were included in this study. Low-count original images (75%, 50%, 25%, 10%, and 5% counts) were generated from reference images (100% counts) using Poisson resampling. Output (DL-filtered) images were obtained after training with U-Net using reference images as teacher data. Gaussian-filtered images were generated for comparison. Peak signal-to-noise ratio (PSNR) and structural similarity (SSIM) to the reference image were calculated to determine image quality. Artificial neural network (ANN) value, bone scan index (BSI), and number of hotspots (Hs) were computed using BONENAVI analysis to assess diagnostic performance. Accuracy of bone metastasis detection and area under the curve (AUC) were calculated. PSNR and SSIM for DL-filtered images were highest in all count percentages. BONENAVI analysis values for DL-filtered images did not differ significantly, regardless of the presence or absence of bone metastases. BONENAVI analysis values for original and Gaussian-filtered images differed significantly at ≦25% counts in patients without bone metastases. In patients with bone metastases, BSI and Hs for original and Gaussian-filtered images differed significantly at ≦10% counts, whereas ANN values did not. The accuracy of bone metastasis detection was highest for DL-filtered images in all count percentages; the AUC did not differ significantly. The deep learning method improved image quality and bone metastasis detection accuracy for low-count bone scintigraphy, suggesting its clinical applicability.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":"269-279"},"PeriodicalIF":1.6,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139713234","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

John Roderick Cameron (1922-2005): Scientist, teacher, mentor, inventor, and philanthropist extraordinaire. 约翰-罗德里克-卡梅隆（1922-2005 年）：杰出的科学家、教师、导师、发明家和慈善家。

IF 1.6

Radiological Physics and Technology Pub Date : 2024-03-01 Epub Date: 2024-02-12 DOI: 10.1007/s12194-023-00775-6

Kwan Hoong Ng, Kunio Doi

引用次数: 0

A practical method to simulate realistic reduced-exposure CT images by the addition of computationally generated noise. 一种实用的方法来模拟真实的减少暴露的CT图像，通过添加计算产生的噪声。

IF 1.6

Radiological Physics and Technology Pub Date : 2024-03-01 Epub Date: 2023-11-13 DOI: 10.1007/s12194-023-00755-w

Nicholas Mark Gibson, Amy Lee, Martin Bencsik

{"title":"A practical method to simulate realistic reduced-exposure CT images by the addition of computationally generated noise.","authors":"Nicholas Mark Gibson, Amy Lee, Martin Bencsik","doi":"10.1007/s12194-023-00755-w","DOIUrl":"10.1007/s12194-023-00755-w","url":null,"abstract":"Computed tomography (CT) scanning protocols should be optimized to minimize the radiation dose necessary for imaging. The addition of computationally generated noise to the CT images facilitates dose reduction. The objective of this study was to develop a noise addition method that reproduces the complexity of the noise texture present in clinical images with directionality that varies over images according to the underlying anatomy, requiring only Digital Imaging and Communications in Medicine (DICOM) images as input data and commonly available phantoms for calibration. The developed method is based on the estimation of projection data by forward projection from images, the addition of Poisson noise, and the reconstruction of new images. The method was validated by applying it to images acquired from cylindrical and thoracic phantoms using source images with exposures up to 49 mAs and target images between 39 and 5 mAs. 2D noise spectra were derived for regions of interest in the generated low-dose images and compared with those from the scanner-acquired low-dose images. The root mean square difference between the standard deviations of noise was 4%, except for very low exposures in peripheral regions of the cylindrical phantom. The noise spectra from the corresponding regions of interest exhibited remarkable agreement, indicating that the complex nature of the noise was reproduced. A practical method for adding noise to CT images was presented, and the magnitudes of noise and spectral content were validated. This method may be used to optimize CT imaging.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":"112-123"},"PeriodicalIF":1.6,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89719972","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

Impact of gadolinium concentration and cell oxygen levels on radiobiological characteristics of gadolinium neutron capture therapy technique in brain tumor treatment. 钆浓度和细胞氧水平对钆中子俘获治疗脑肿瘤技术放射生物学特性的影响。

IF 1.6

Radiological Physics and Technology Pub Date : 2024-03-01 Epub Date: 2023-11-21 DOI: 10.1007/s12194-023-00758-7

Reza Shamsabadi, Hamid Reza Baghani

{"title":"Impact of gadolinium concentration and cell oxygen levels on radiobiological characteristics of gadolinium neutron capture therapy technique in brain tumor treatment.","authors":"Reza Shamsabadi, Hamid Reza Baghani","doi":"10.1007/s12194-023-00758-7","DOIUrl":"10.1007/s12194-023-00758-7","url":null,"abstract":"Neutron capture therapy (NCT) with various concentrations of gadolinium (157Gd) is one of the treatment modalities for glioblastoma (GBM) tumors. Current study aims to evaluate how variations of 157Gd concentration and cell oxygen levels can affect the relative biological effectiveness (RBE) of gadolinium neutron capture therapy (GdNCT) technique through a hybrid Monte Carlo (MC) simulation approach. At first, Snyder phantom including a spherical tumor was simulated by Geant4 MC code and relevant energy electron spectra to different 157Gd concentrations including 100, 250, 500, and 1000 ppm were calculated following the neutron irradiation of simulated phantom. Scored energy electron spectra were then imported to Monte Carlo damage simulation (MCDS) code to estimate RBE values (both RBESSB and RBEDSB) at different gadolinium concentrations and oxygen levels from 10 to 100%. The results indicate that variations of 157Gd can affect the energy spectrum of released secondary electrons including Auger electrons. Variation of gadolinium concentration from 100 to 1000 ppm in tumor region can change RBESSB and RBEDSB values by about 0.1% and 0.5%, respectively. Besides, maximum variations of 4.3% and 2% were calculated for RBEDSB and RBESSB when cell oxygen level changed from 10 to 100%. From the results, variations of considered gadolinium and oxygen concentrations during GdNCT can influence RBE values. Nevertheless, due to the not remarkable changes in the intensity of Auger electrons, a slight difference in RBE values would be expected at various 157Gd concentrations, although considerable RBE changes were calculated relevant to the oxygen alternations inside tumor tissue.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":"135-142"},"PeriodicalIF":1.6,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138292045","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

Investigation of uncertainty in internal target volume definition for lung stereotactic body radiotherapy. 肺立体定向放射治疗靶体积内定义不确定度的探讨。

IF 1.6

Radiological Physics and Technology Pub Date : 2023-12-01 Epub Date: 2023-09-15 DOI: 10.1007/s12194-023-00737-y

Daiki Nakanishi, Masataka Oita, Jun-Ichi Fukunaga, Taka-Aki Hirose, Tadamasa Yoshitake, Motoharu Sasaki

{"title":"Investigation of uncertainty in internal target volume definition for lung stereotactic body radiotherapy.","authors":"Daiki Nakanishi, Masataka Oita, Jun-Ichi Fukunaga, Taka-Aki Hirose, Tadamasa Yoshitake, Motoharu Sasaki","doi":"10.1007/s12194-023-00737-y","DOIUrl":"10.1007/s12194-023-00737-y","url":null,"abstract":"This study evaluated the validity of internal target volumes (ITVs) defined by three- (3DCT) and four-dimensional computed tomography (4DCT), and subsequently compared them with actual movements during treatment. Five patients with upper lobe lung tumors were treated with stereotactic body radiotherapy (SBRT) at 48 Gy in four fractions. Planning 3DCT images were acquired with peak-exhale and peak-inhale breath-holds, and 4DCT images were acquired in the cine mode under free breathing. Cine images were acquired using an electronic portal imaging device during irradiation. Tumor coverage was evaluated based on the manner in which the peak-to-peak breathing amplitude on the planning CT covered the range of tumor motion (± 3 SD) during irradiation in the left-right, anteroposterior, and cranio-caudal (CC) directions. The mean tumor coverage of the 4DCT-based ITV was better than that of the 3DCT-based ITV in the CC direction. The internal margin should be considered when setting the irradiation field for 4DCT. The proposed 4DCT-based ITV can be used as an efficient approach in free-breathing SBRT for upper-lobe tumors of the lung because its coverage is superior to that of 3DCT.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":"497-505"},"PeriodicalIF":1.6,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10665452/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10246171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Creation, evolution, and future challenges of ion beam therapy from a medical physicist's viewpoint (Part 3): Chapter 3. Clinical research, Chapter 4. Future challenges, Chapter 5. Discussion, and Conclusion. 从医学物理学家的角度看离子束疗法的产生、进化和未来挑战（第3部分）：第3章。临床研究，第4章。未来的挑战，第5章。讨论和结论。

IF 1.6

Radiological Physics and Technology Pub Date : 2023-12-01 Epub Date: 2023-10-26 DOI: 10.1007/s12194-023-00748-9

Masahiro Endo

{"title":"Creation, evolution, and future challenges of ion beam therapy from a medical physicist's viewpoint (Part 3): Chapter 3. Clinical research, Chapter 4. Future challenges, Chapter 5. Discussion, and Conclusion.","authors":"Masahiro Endo","doi":"10.1007/s12194-023-00748-9","DOIUrl":"10.1007/s12194-023-00748-9","url":null,"abstract":"Clinical studies of ion beam therapy have been performed at the Lawrence Berkeley Laboratory (LBL), National Institute of Radiological Sciences (NIRS), Gesellschaft für Schwerionenforschung (GSI), and Deutsches Krebsforschungszentrum (DKFZ), in addition to the development of equipment, biophysical models, and treatment planning systems. Although cancers, including brain tumors and pancreatic cancer, have been treated with the Bevalac's neon-ion beam at the LBL (where the first clinical research was conducted), insufficient results were obtained owing to the limited availability of neon-ion beams and immaturity of related technologies. However, the 184-Inch Cyclotron's helium-ion beam yielded promising results for chordomas and chondrosarcomas at the base of the skull. Using carbon-ion beams, NIRS has conducted clinical trials for the treatment of common cancers for which radiotherapy is indicated. Because better results than X-ray therapy results have been obtained for lung, liver, pancreas, and prostate cancers, as well as pelvic recurrences of rectal cancer, the Japanese government recently approved the use of public medical insurance for carbon-ion radiotherapy, except for lung cancer. GSI obtained better results than LBL for bone and soft tissue tumors, owing to dose enhancement enabled by scanning irradiation. In addition, DKFZ compared treatment results of proton and carbon-ion radiotherapy for these tumors. This article summarizes a series of articles (Parts 1-3) and describes future issues of immune ion beam therapy and linear energy transfer optimization.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":"443-470"},"PeriodicalIF":1.6,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50163221","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