Radiological Physics and Technology最新文献

筛选
英文 中文
Development of deep learning-based novel auto-segmentation for the prostatic urethra on planning CT images for prostate cancer radiotherapy. 在前列腺癌放疗计划 CT 图像上开发基于深度学习的新型前列腺尿道自动分割技术。
IF 1.7
Radiological Physics and Technology Pub Date : 2024-12-01 Epub Date: 2024-08-14 DOI: 10.1007/s12194-024-00832-8
Hisamichi Takagi, Ken Takeda, Noriyuki Kadoya, Koki Inoue, Shiki Endo, Noriyoshi Takahashi, Takaya Yamamoto, Rei Umezawa, Keiichi Jingu
{"title":"Development of deep learning-based novel auto-segmentation for the prostatic urethra on planning CT images for prostate cancer radiotherapy.","authors":"Hisamichi Takagi, Ken Takeda, Noriyuki Kadoya, Koki Inoue, Shiki Endo, Noriyoshi Takahashi, Takaya Yamamoto, Rei Umezawa, Keiichi Jingu","doi":"10.1007/s12194-024-00832-8","DOIUrl":"10.1007/s12194-024-00832-8","url":null,"abstract":"<p><p>Urinary toxicities are one of the serious complications of radiotherapy for prostate cancer, and dose-volume histogram of prostatic urethra has been associated with such toxicities in previous reports. Previous research has focused on estimating the prostatic urethra, which is difficult to delineate in CT images; however, these studies, which are limited in number, mainly focused on cases undergoing brachytherapy uses low-dose-rate sources and do not involve external beam radiation therapy (EBRT). In this study, we aimed to develop a deep learning-based method of determining the position of the prostatic urethra in patients eligible for EBRT. We used contour data from 430 patients with localized prostate cancer. In all cases, a urethral catheter was placed when planning CT to identify the prostatic urethra. We used 2D and 3D U-Net segmentation models. The input images included the bladder and prostate, while the output images focused on the prostatic urethra. The 2D model determined the prostate's position based on results from both coronal and sagittal directions. Evaluation metrics included the average distance between centerlines. The average centerline distances for the 2D and 3D models were 2.07 ± 0.87 mm and 2.05 ± 0.92 mm, respectively. Increasing the number of cases while maintaining equivalent accuracy as we did in this study suggests the potential for high generalization performance and the feasibility of using deep learning technology for estimating the position of the prostatic urethra.</p>","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":"819-826"},"PeriodicalIF":1.7,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11579160/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141983522","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
Assessment of accuracy and repeatability of quantitative parameter mapping in MRI. 评估磁共振成像定量参数绘图的准确性和可重复性。
IF 1.7
Radiological Physics and Technology Pub Date : 2024-12-01 Epub Date: 2024-08-28 DOI: 10.1007/s12194-024-00836-4
Yuya Hirano, Kinya Ishizaka, Hiroyuki Sugimori, Yo Taniguchi, Tomoki Amemiya, Yoshitaka Bito, Kohsuke Kudo
{"title":"Assessment of accuracy and repeatability of quantitative parameter mapping in MRI.","authors":"Yuya Hirano, Kinya Ishizaka, Hiroyuki Sugimori, Yo Taniguchi, Tomoki Amemiya, Yoshitaka Bito, Kohsuke Kudo","doi":"10.1007/s12194-024-00836-4","DOIUrl":"10.1007/s12194-024-00836-4","url":null,"abstract":"<p><p>We aimed to evaluate the accuracy and repeatability of the T1, T2*, and proton density (PD) values obtained by quantitative parameter mapping (QPM) using the ISMRM/NIST MRI system phantom and compared them with computer simulations. We compared the relaxation times and PD obtained through QPM with the reference values of the ISMRM/NIST MRI system phantom and conventional methods. Furthermore, we evaluated the presence or absence of influences other than noise in T1 and T2* values obtained by QPM by comparing the obtained coefficient of variation (CV) with simulation results. The T1, T2*, and PD values by QPM showed a strong correlation with the measured values and the referenced values. The simulated CVs of QPM calculated for each sphere showed similar trends to those of the actual scans.</p>","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":"918-928"},"PeriodicalIF":1.7,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11579128/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142093953","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
Joint segmentation of sternocleidomastoid and skeletal muscles in computed tomography images using a multiclass learning approach. 利用多类学习方法联合分割计算机断层扫描图像中的胸锁乳突肌和骨骼肌
IF 1.7
Radiological Physics and Technology Pub Date : 2024-12-01 Epub Date: 2024-09-06 DOI: 10.1007/s12194-024-00839-1
Kosuke Ashino, Naoki Kamiya, Xiangrong Zhou, Hiroki Kato, Takeshi Hara, Hiroshi Fujita
{"title":"Joint segmentation of sternocleidomastoid and skeletal muscles in computed tomography images using a multiclass learning approach.","authors":"Kosuke Ashino, Naoki Kamiya, Xiangrong Zhou, Hiroki Kato, Takeshi Hara, Hiroshi Fujita","doi":"10.1007/s12194-024-00839-1","DOIUrl":"10.1007/s12194-024-00839-1","url":null,"abstract":"<p><p>Deep-learning-based methods can improve robustness against individual variations in computed tomography (CT) images of the sternocleidomastoid muscle, which is a challenge when using conventional methods based on probabilistic atlases are used for automatic segmentation. Thus, this study proposes a novel multiclass learning approach for the joint segmentation of the sternocleidomastoid and skeletal muscles in CT images, and it employs a two-dimensional U-Net architecture. The proposed method concurrently learns and segmented segments the sternocleidomastoid muscle and the entire skeletal musculature. Consequently, three-dimensional segmentation results are generated for both muscle groups. Experiments conducted on a dataset of 30 body CT images demonstrated segmentation accuracies of 82.94% and 92.73% for the sternocleidomastoid muscle and entire skeletal muscle compartment, respectively. These results outperformed those of conventional methods, such as the single-region learning of a target muscle and multiclass learning of specific muscle pairs. Moreover, the multiclass learning paradigm facilitated a robust segmentation performance regardless of the input image range. This highlights the method's potential for cases that present muscle atrophy or reduced muscle strength. The proposed method exhibits promising capabilities for the high-accuracy joint segmentation of the sternocleidomastoid and skeletal muscles and is effective in recognizing skeletal muscles, thus, it holds promise for integration into computer-aided diagnostic systems for comprehensive musculoskeletal analysis. These findings are expected to enhance medical image analysis techniques and their applications in clinical decision support systems.</p>","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":"854-861"},"PeriodicalIF":1.7,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11579203/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142146574","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
Evaluation of dynamic accuracy and latency of a surface-guided radiotherapy system. 表面引导放射治疗系统动态精度和延迟的评价。
IF 1.7
Radiological Physics and Technology Pub Date : 2024-11-28 DOI: 10.1007/s12194-024-00866-y
Ryohei Yamauchi, Fumihiro Tomita
{"title":"Evaluation of dynamic accuracy and latency of a surface-guided radiotherapy system.","authors":"Ryohei Yamauchi, Fumihiro Tomita","doi":"10.1007/s12194-024-00866-y","DOIUrl":"https://doi.org/10.1007/s12194-024-00866-y","url":null,"abstract":"<p><p>The aim of this study is to evaluate the dynamic accuracy and latency of the surface-guided radiotherapy (SGRT) system using TrueBeam and AlignRT in compliance with SGRT guidelines. Beam characteristics-flatness, symmetry, beam quality, and output-were compared between gated and nongated beams using a two-dimensional ionization chamber array and a Farmer-type chamber. Dynamic accuracy was assessed using a moving platform and breast phantom, with measurements taken for various shift values (5, 10, 30 mm), region-of-interest (ROI) shapes, reference-surface image types (DICOM and capture), surface resolutions, and room illuminations. Latency due to differences in frame rates was evaluated using radiochromic film, calculated from position displacements of profiles at two speeds. Differences in beam characteristics between gated and nongated beams were within 0.1%. Dynamic accuracy showed minimal dependence on settings, with deviations of < 1 mm for a 10-mm shift. A maximum displacement of 1.9 mm was observed with a 30-mm shift at the body ROI. Beam-on latency at 12, 16, 25, and 35 frames per second was 253.2 ± 21.9, 225.7 ± 33.7, 177.1 ± 43.0, and 112.4 ± 29.2 ms, respectively, with similar trends for beam-off latency. This study is the first to evaluate the dynamic accuracy of the TrueBeam and AlignRT system under SGRT-specific settings. While accuracy was generally maintained (< 1 mm), ROI shape significantly impacted results. Latency results indicate that certain frame rates may not meet guideline limits, underscoring the need for careful SGRT system use in clinical applications.</p>","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142751987","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 uterine displacement on T2-weighted image quality in the female pelvic MRI. 子宫移位对女性盆腔磁共振 T2 加权成像质量的影响
IF 1.7
Radiological Physics and Technology Pub Date : 2024-11-26 DOI: 10.1007/s12194-024-00861-3
Hironobu Ishikawa, Masahiko Monma, Yoshiyuki Ishimori, Kousaku Saotome, Shiro Ishii, Hirofumi Sekino, Ryo Yamakuni, Takeyasu Kakamu, Daisuke Oura, Yuma Takahashi, Shinya Seino, Masanori Yusa, Hiroshi Ito
{"title":"Impact of uterine displacement on T<sub>2</sub>-weighted image quality in the female pelvic MRI.","authors":"Hironobu Ishikawa, Masahiko Monma, Yoshiyuki Ishimori, Kousaku Saotome, Shiro Ishii, Hirofumi Sekino, Ryo Yamakuni, Takeyasu Kakamu, Daisuke Oura, Yuma Takahashi, Shinya Seino, Masanori Yusa, Hiroshi Ito","doi":"10.1007/s12194-024-00861-3","DOIUrl":"https://doi.org/10.1007/s12194-024-00861-3","url":null,"abstract":"<p><p>Despite the importance of T<sub>2</sub>-weighted image in clinical practice, artifacts can significantly degrade image quality and affect diagnosis. This study quantitatively analyzed uterine displacement and surveyed the relationship between the image quality of fast-spin-echo-T<sub>2</sub>-weighted image of the female pelvis and quantitative value of uterine displacement. Overall, 147 women (mean age, 46.0 ± 12.8 years; age range, 22-84 years) who had undergone pelvic magnetic resonance imaging examination using a 3 T- magnetic resonance imaging scanner were included. Two radiologists performed a visual assessment of the fast-spin-echo-T<sub>2</sub>-weighted image in the sagittal plane in terms of ghosts and motion blur, and classified the image quality into the following three groups: poor, moderate, and excellent. Uterine displacement on half-Fourier acquisition single-shot turbo spin-echo-cine images was calculated, and the maximum amplitude of uterine displacement and summation of uterine displacement were calculated from the displacement map images. The Kruskal-Wallis and Steel-Dwass tests were performed to compare the maximum amplitude of uterine displacement and summation of uterine displacement among the three groups. Poor, moderate, and excellent image qualities were observed in 48, 71, and 28 patients, respectively. The quality of fast-spin-echo-T<sub>2</sub>-weighted images degraded statistically significantly with P < 0.01 as the maximum amplitude of uterine displacement increased. The summation of uterine displacement in the poor and moderate groups had greater statistical significance with P < 0.01 than that in the excellent group.</p>","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142733262","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
Standardization of radiation therapy quality control system through mutual quality control based on failure mode and effects analysis. 通过基于失效模式和效应分析的相互质量控制,实现放射治疗质量控制系统的标准化。
IF 1.7
Radiological Physics and Technology Pub Date : 2024-11-18 DOI: 10.1007/s12194-024-00857-z
Yuki Tanimoto, Masataka Oita, Kazunobu Koshi, Kiyoshi Ishiwaki, Futoshi Hiramatsu, Toshihisa Sasaki, Hiroki Ise, Takashi Miyagawa, Takeshi Maeda, Shinsuke Okahira, Takashi Hamaguchi, Tatsuya Kawaguchi, Norihiro Funada, Shuhei Yamamoto, Akira Hiroshige, Yuki Mukai, Shohei Yoshida, Yoshiki Fujita, Atsuki Nakahira, Hirofumi Honda
{"title":"Standardization of radiation therapy quality control system through mutual quality control based on failure mode and effects analysis.","authors":"Yuki Tanimoto, Masataka Oita, Kazunobu Koshi, Kiyoshi Ishiwaki, Futoshi Hiramatsu, Toshihisa Sasaki, Hiroki Ise, Takashi Miyagawa, Takeshi Maeda, Shinsuke Okahira, Takashi Hamaguchi, Tatsuya Kawaguchi, Norihiro Funada, Shuhei Yamamoto, Akira Hiroshige, Yuki Mukai, Shohei Yoshida, Yoshiki Fujita, Atsuki Nakahira, Hirofumi Honda","doi":"10.1007/s12194-024-00857-z","DOIUrl":"10.1007/s12194-024-00857-z","url":null,"abstract":"<p><p>The advancement of irradiation technology has increased the demand for quality control of radiation therapy equipment. Consequently, the number of quality control items and required personnel have also increased. However, differences in the proportion of qualified personnel to irradiation techniques have caused bias in quality control systems among institutions. To standardize the quality across institutions, researchers should conduct mutual quality control by analyzing the quality control data of one institution at another institution and comparing the results with those of their own institutions. This study uses failure mode and effects analysis (FMEA) to identify potential risks in 12 radiation therapy institutions, compares the results before and after implementation of mutual quality control, and examines the utility of mutual quality control in risk reduction. Furthermore, a cost-effectiveness factor is introduced into FMEA to evaluate the utility of mutual quality control.</p>","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142668900","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
Quantification of uncertainties in reference and relative dose measurements, dose calculations, and patient setup in modern external beam radiotherapy. 量化现代体外放射治疗中参考和相对剂量测量、剂量计算和患者设置的不确定性。
IF 1.7
Radiological Physics and Technology Pub Date : 2024-11-14 DOI: 10.1007/s12194-024-00856-0
Naoki Kinoshita, Morihito Shimizu, Kana Motegi, Yusuke Tsuruta, Toru Takakura, Hiroshi Oguchi, Chie Kurokawa
{"title":"Quantification of uncertainties in reference and relative dose measurements, dose calculations, and patient setup in modern external beam radiotherapy.","authors":"Naoki Kinoshita, Morihito Shimizu, Kana Motegi, Yusuke Tsuruta, Toru Takakura, Hiroshi Oguchi, Chie Kurokawa","doi":"10.1007/s12194-024-00856-0","DOIUrl":"https://doi.org/10.1007/s12194-024-00856-0","url":null,"abstract":"<p><p>Uncertainties in the steps of external beam radiotherapy (EBRT) affect patient outcomes. However, few studies have investigated major contributors to these uncertainties. This study investigated factors contributing to reducing uncertainty in delivering a dose to a target volume. The EBRT process was classified into four steps: reference dosimetry, relative dosimetry [percentage depth doses (PDDs) and off-center ratios (OCRs)], dose calculations (PDDs and OCRs in a virtual water phantom), and patient setup using an image-guided radiation therapy system. We evaluated the uncertainties for these steps in conventionally fractionated EBRT for intracranial disease using 4-, 6-, and 10-MV flattened photon beams generated from clinical linear accelerators following the Guide to the Expression of Uncertainty in Measurement and an uncertainty evaluation method with uncorrected deflection. The following were the major contributors to these uncertainties: beam quality conversion factors for reference dosimetry; charge measurements, chamber depth, source-to-surface distance, water evaporation, and field size for relative dosimetry; dose calculation accuracy for the dose calculations; image registration, radiation-imaging isocenter coincidence, variation in radiation isocenter due to gantry and couch rotation, and intrafractional motion for the patient setup. Among the four steps, the relative dosimetry and dose calculation (namely, both penumbral OCRs) steps involved an uncertainty of more than 5% with a coverage factor of 1. In the EBRT process evaluated herein, the uncertainties in the relative dosimetry and dose calculations must be reduced.</p>","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142630162","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 dose distributions and respiratory motion tolerance for layer-stacking conformal carbon-ion radiotherapy. 评估层叠适形碳离子放射治疗的剂量分布和呼吸运动耐受性。
IF 1.7
Radiological Physics and Technology Pub Date : 2024-11-14 DOI: 10.1007/s12194-024-00847-1
Yuki Hasebe, Mutsumi Tashiro, Hiroshi Sakurai
{"title":"Evaluation of dose distributions and respiratory motion tolerance for layer-stacking conformal carbon-ion radiotherapy.","authors":"Yuki Hasebe, Mutsumi Tashiro, Hiroshi Sakurai","doi":"10.1007/s12194-024-00847-1","DOIUrl":"https://doi.org/10.1007/s12194-024-00847-1","url":null,"abstract":"<p><p>While layer-stacking irradiation provides a conformal dose distribution, it is vulnerable to respiratory motion. Considering that the motion tolerance has not yet been demonstrated, this study aimed to determine the tolerance level for the amount of target motion. Dose distributions considering motion were simulated for a numerical water phantom using in-house software. Comparisons with measured and simulated physical dose distributions confirmed the validity of the simulation, with gamma analysis showing almost 90% or greater agreement under all conditions with a criterion of 3%/3 mm. The variation in physical dose from static conditions followed a similar trend. Based on the evaluation of the simulated clinical dose uniformity, motion tolerance was derived. The acceptable motion amounts in the lateral direction were 11 mm in respiratory-ungated condition and at least 20 mm with 30% lateral gating at 4 Gy (RBE). In the longitudinal (beam upstream) direction, the acceptable target motion amounts were 3 mm without gating and 6 mm with gating. These results employed worst-case scenarios considering multiple respiratory cycles. In both lateral and longitudinal directions, the motion amounts of 3 mm for non-gating and 5 mm for gating were acceptable. The acceptable target motion amounts improved by 1-9 mm with gating and increased prescribed doses. The dose uniformity and motion tolerance under multiple conditions, although based on a simple system, may be useful for treatment involving target motion in layer-stacking irradiation.</p>","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142630070","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
Comprehensive image quality comparison of conventional and new flat panel detectors under bedside chest radiography beam conditions. 在床边胸部放射光束条件下,对传统和新型平板探测器的图像质量进行综合比较。
IF 1.7
Radiological Physics and Technology Pub Date : 2024-11-13 DOI: 10.1007/s12194-024-00859-x
Sho Maruyama, Hiroki Saitou
{"title":"Comprehensive image quality comparison of conventional and new flat panel detectors under bedside chest radiography beam conditions.","authors":"Sho Maruyama, Hiroki Saitou","doi":"10.1007/s12194-024-00859-x","DOIUrl":"https://doi.org/10.1007/s12194-024-00859-x","url":null,"abstract":"<p><p>Recently, a novel wireless flat-panel detector with auto-exposure control has become available. This study aimed to elucidate the potential advantages of the new detector over conventional detectors through a comprehensive analysis of the physical image quality characteristics. Measurements were conducted on two models: new (720C) and conventional (710C) versions; this assessment was performed by assuming the beam quality for bedside chest radiography, utilizing a portable device for X-ray exposure. The detective quantum efficiency (DQE) was computed based on the presampled modulation transfer function (MTF) and normalized noise power spectrum. The validity of the DQE results was verified through the visualization of the analog blurring components and a detailed analysis of the noise components. The spatial frequency at which the presampled MTF value reached 10% was 5.2 cycles/mm for 720C and 3.9 cycles/mm for 710C. The full width at half-maximum of the spatial spreading of analog components was estimated at 0.09 mm for 720C and 0.14 mm for 710C by the visualization. Regarding the DQE, 720C was superior under low-dose conditions despite no significant differences being observed under high-dose conditions. The new detector demonstrated superior resolution characteristics compared with the conventional detector and an improvement in the DQE under low-dose conditions. However, similar to the conventional detector, a significant dose dependence caused by a structural factor was confirmed for the DQE. These results suggest the existence of an appropriate dose range for maximizing detector performance and provide insights crucial for optimization tasks in the X-ray imaging.</p>","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142630065","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
Pulsation artifact reduction using compressed sensitivity encoding in Gd-EOB-DTPA contrast-enhanced magnetic resonance imaging. 在 Gd-EOB-DTPA 对比增强磁共振成像中使用压缩灵敏度编码减少脉动伪影。
IF 1.7
Radiological Physics and Technology Pub Date : 2024-11-07 DOI: 10.1007/s12194-024-00858-y
Masafumi Nakamura, Yasuo Takatsu, Mutsumi Yoshizawa, Kenichiro Yamamura, Tosiaki Miyati
{"title":"Pulsation artifact reduction using compressed sensitivity encoding in Gd-EOB-DTPA contrast-enhanced magnetic resonance imaging.","authors":"Masafumi Nakamura, Yasuo Takatsu, Mutsumi Yoshizawa, Kenichiro Yamamura, Tosiaki Miyati","doi":"10.1007/s12194-024-00858-y","DOIUrl":"https://doi.org/10.1007/s12194-024-00858-y","url":null,"abstract":"<p><p>In Gd-EOB-DTPA-enhanced MRI, cardiac pulsation artifacts in the left lobe often hinder diagnosis, the image quality need to improve. This study aimed to reduce cardiac pulsation artifacts in Gd-EOB-DTPA-enhanced three-dimensional (3D) T1-weighted turbo-field echo (3D-T1TFE) using compressed sensitivity encoding (CS).For phantom evaluation, the cardiac phantom was manually operated using a metronome-synchronized apparatus, comprising a bag-valve mask, a breathing circuit, and a Jackson-Rees system. Transverse images of a liver phantom were acquired using enhanced T1 high-resolution isotropic volumetric excitation with CS (CS-eTHRIVE) and sensitivity encoding (S-eTHRIVE). For evaluation, images obtained during cardiac phantom operation were subtracted from those obtained when the phantom was stationary. Standard deviation (SD) of the difference images was used as the evaluation metric, and assessments were conducted based on changes in heart rate and TFE factor. For clinical image evaluation, artifacts in hepatobiliary phase images acquired 15 min after Gd-EOB-DTPA injection in the order of S-eTHRIVE and CS-eTHRIVE were visually evaluated at four levels. In heart-rate evaluation (40, 60, and 80 beats/min), CS-eTHRIVE revealed significantly lower SD values compared to S-eTHRIVE across all heart rates (P < 0.01), with no significant differences between heart rates. For TFE factor evaluation, CS-eTHRIVE with a factor of 35 exhibited the lowest SD, which was significantly different from all other groups (P < 0.01). In clinical image evaluation, CS-eTHRIVE achieved higher visual scores (mean ± SD: 3.72 ± 0.46) compared with S-eTHRIVE (2.72 ± 0.98, P < 0.01).CS reduced pulsation artifacts in Gd-EOB-DTPA-enhanced 3D-T1TFE.</p>","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142606819","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
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信