Radiological Physics and Technology最新文献_第5页

External and internal GATE/Geant4 dosimetric calculations on voxelized phantoms. 体素化幻影的外部和内部GATE/Geant4剂量学计算。

IF 1.7

Radiological Physics and Technology Pub Date : 2025-06-01 Epub Date: 2025-04-11 DOI: 10.1007/s12194-025-00904-3

Merai Sondes, Benrachi Fatima, Laouet Nadjet

引用次数: 0

A CT-free deep-learning-based attenuation and scatter correction for copper-64 PET in different time-point scans. 基于深度学习的铜-64 PET在不同时间点扫描中的衰减和散射校正。

IF 1.7

Radiological Physics and Technology Pub Date : 2025-06-01 Epub Date: 2025-04-22 DOI: 10.1007/s12194-025-00905-2

Zahra Adeli, Seyed Abolfazl Hosseini, Yazdan Salimi, Nasim Vahidfar, Peyman Sheikhzadeh

{"title":"A CT-free deep-learning-based attenuation and scatter correction for copper-64 PET in different time-point scans.","authors":"Zahra Adeli, Seyed Abolfazl Hosseini, Yazdan Salimi, Nasim Vahidfar, Peyman Sheikhzadeh","doi":"10.1007/s12194-025-00905-2","DOIUrl":"10.1007/s12194-025-00905-2","url":null,"abstract":"This study aimed to develop and evaluate a deep-learning model for attenuation and scatter correction in whole-body 64Cu-based PET imaging. A swinUNETR model was implemented using the MONAI framework. Whole-body PET-nonAC and PET-CTAC image pairs were used for training, where PET-nonAC served as the input and PET-CTAC as the output. Due to the limited number of Cu-based PET/CT images, a model pre-trained on 51 Ga-PSMA PET images was fine-tuned on 15 Cu-based PET images via transfer learning. The model was trained without freezing layers, adapting learned features to the Cu-based dataset. For testing, six additional Cu-based PET images were used, representing 1-h, 12-h, and 48-h time points, with two images per group. The model performed best at the 12-h time point, with an MSE of 0.002 ± 0.0004 SUV2, PSNR of 43.14 ± 0.08 dB, and SSIM of 0.981 ± 0.002. At 48 h, accuracy slightly decreased (MSE = 0.036 ± 0.034 SUV2), but image quality remained high (PSNR = 44.49 ± 1.09 dB, SSIM = 0.981 ± 0.006). At 1 h, the model also showed strong results (MSE = 0.024 ± 0.002 SUV2, PSNR = 45.89 ± 5.23 dB, SSIM = 0.984 ± 0.005), demonstrating consistency across time points. Despite the limited size of the training dataset, the use of fine-tuning from a previously pre-trained model yielded acceptable performance. The results demonstrate that the proposed deep learning model can effectively generate PET-DLAC images that closely resemble PET-CTAC images, with only minor errors.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":"523-533"},"PeriodicalIF":1.7,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144054069","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

Retaking assessment system based on the inspiratory state of chest X-ray image. 基于胸部x线图像吸气状态的重拍评估系统。

IF 1.7

Radiological Physics and Technology Pub Date : 2025-06-01 Epub Date: 2025-02-19 DOI: 10.1007/s12194-025-00888-0

Naoki Matsubara, Atsushi Teramoto, Manabu Takei, Yoshihiro Kitoh, Satoshi Kawakami

{"title":"Retaking assessment system based on the inspiratory state of chest X-ray image.","authors":"Naoki Matsubara, Atsushi Teramoto, Manabu Takei, Yoshihiro Kitoh, Satoshi Kawakami","doi":"10.1007/s12194-025-00888-0","DOIUrl":"10.1007/s12194-025-00888-0","url":null,"abstract":"When taking chest X-rays, the patient is encouraged to take maximum inspiration and the radiological technologist takes the images at the appropriate time. If the image is not taken at maximum inspiration, retaking of the image is required. However, there is variation in the judgment of whether retaking is necessary between the operators. Therefore, we considered that it might be possible to reduce variation in judgment by developing a retaking assessment system that evaluates whether retaking is necessary using a convolutional neural network (CNN). To train the CNN, the input chest X-ray image and the corresponding correct label indicating whether retaking is necessary are required. However, chest X-ray images cannot distinguish whether inspiration is sufficient and does not need to be retaken, or insufficient and retaking is required. Therefore, we generated input images and labels from dynamic digital radiography (DDR) and conducted the training. Verification using 18 dynamic chest X-ray cases (5400 images) and 48 actual chest X-ray cases (96 images) showed that the VGG16-based architecture achieved an assessment accuracy of 82.3% even for actual chest X-ray images. Therefore, if the proposed method is used in hospitals, it could possibly reduce the variability in judgment between operators.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":"384-398"},"PeriodicalIF":1.7,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12103368/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143450583","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

Impact of a novel respiratory motion reduction block for myocardial perfusion SPECT image quality: a phantom study. 一种新型呼吸运动减少阻滞对心肌灌注SPECT图像质量的影响：一项幻影研究。

IF 1.7

Radiological Physics and Technology Pub Date : 2025-06-01 Epub Date: 2025-02-18 DOI: 10.1007/s12194-025-00887-1

Hajime Ichikawa, Toyohiro Kato, Takayuki Shibutani, Mitsuaki Terabe, Hideki Shimada

{"title":"Impact of a novel respiratory motion reduction block for myocardial perfusion SPECT image quality: a phantom study.","authors":"Hajime Ichikawa, Toyohiro Kato, Takayuki Shibutani, Mitsuaki Terabe, Hideki Shimada","doi":"10.1007/s12194-025-00887-1","DOIUrl":"10.1007/s12194-025-00887-1","url":null,"abstract":"Patient motion, particularly due to respiration, often introduces image distortions that compromise diagnostic accuracy in myocardial perfusion single-photon emission computed tomography (SPECT). To address this issue, we developed a novel respiratory motion reduction block (RRB) designed to minimize the respiratory motion of the heart. This study aims to evaluate the impact of the cardiac-centered with RRB (CCRRB) orbit, achieved using the RRB, on myocardial perfusion SPECT image quality. SPECT acquisition of a cardiac phantom was performed at the circular, neighboring elliptical (NE), and CCRRB orbits. The CCRRB orbit was achieved with RRB placed in front of the phantom based on the NE orbit. Count profile curves of the lesion and uniform slice images were obtained from the circumferential profile. Lesion contrast, normal accumulation uniformity, and count distortion were calculated from the circumferential profiles. Full width at half maximum (FWHM) was measured in the lateral, anterior, septal, and inferior walls of the myocardium, and both the mean and standard deviation (SD) were calculated. The lesion contrast was the highest in the NE orbit, slightly lower in the CCRRB orbit, and remarkably lower in the circular orbit than in the NE orbit. The uniformity and count distortion were superior for the CCRRB orbits. The SD of FWHM was greater in the circular and NE orbits. The CCRRB orbit effectively improves uniformity in SPECT imaging, preserving lesion contrast and spatial resolution. The CCRRB orbit provides a practical, accessible approach for enhancing image quality in clinical settings.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":"376-383"},"PeriodicalIF":1.7,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143450617","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

Effectiveness of radiation protection educational material during angiography using visualization of scattered radiation by augmented reality technique. 增强现实技术在血管造影中散射辐射可视化辐射防护教材的有效性。

IF 1.7

Radiological Physics and Technology Pub Date : 2025-06-01 Epub Date: 2025-03-19 DOI: 10.1007/s12194-025-00899-x

Koki Noguchi, Toshioh Fujibuchi, Donghee Han

{"title":"Effectiveness of radiation protection educational material during angiography using visualization of scattered radiation by augmented reality technique.","authors":"Koki Noguchi, Toshioh Fujibuchi, Donghee Han","doi":"10.1007/s12194-025-00899-x","DOIUrl":"10.1007/s12194-025-00899-x","url":null,"abstract":"In medical settings, radiation exposure among radiation workers is a significant concern, and understanding radiation protection is crucial. We developed and evaluated radiation protection educational materials using an augmented reality application for visualizing scatter radiation. The evaluation included a true/false quiz, a questionnaire based on the ARCS (Attention, Relevance, Confidence, and Satisfaction) model, and open-ended responses. The correct response rates for the true/false quiz were 65.5% and 72.4% for two questions regarding the effect of C-arm angle changes on scatter radiation distribution. The correct response rate for all other questions was 100%. Understanding how changes in C-arm angles specifically affect angiographic procedures proved more challenging than other topics. The ARCS model evaluation of learning motivation revealed average scores of 4.15 for Attention, 3.91 for Relevance, 3.93 for Confidence, and 4.28 for Satisfaction in the scale 5.00.These results suggest that the developed materials are effective in enhancing motivation. However, open-ended responses identified areas for improvement in the application's usability, particularly regarding ease of operation. While the materials successfully enhance motivation, further refinements are needed to address the variation in correct response rates across different scenarios and the usability challenges of the application.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":"484-495"},"PeriodicalIF":1.7,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143664868","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

Risk factors for motion artifacts in fast spin-echo T2-weighted imaging of the prostate magnetic resonance imaging: a retrospective study. 前列腺磁共振成像快速自旋回波 T2 加权成像中出现运动伪影的风险因素：一项回顾性研究。

IF 1.7

Radiological Physics and Technology Pub Date : 2025-06-01 Epub Date: 2025-03-21 DOI: 10.1007/s12194-025-00897-z

Takuya Kobata, Tatsuya Yamasaki, Hiroki Katayama, Masatoshi Morimoto, Yukito Maeda, Takashi Norikane, Yuka Yamamoto, Yoshihiro Nishiyama

{"title":"Risk factors for motion artifacts in fast spin-echo T2-weighted imaging of the prostate magnetic resonance imaging: a retrospective study.","authors":"Takuya Kobata, Tatsuya Yamasaki, Hiroki Katayama, Masatoshi Morimoto, Yukito Maeda, Takashi Norikane, Yuka Yamamoto, Yoshihiro Nishiyama","doi":"10.1007/s12194-025-00897-z","DOIUrl":"10.1007/s12194-025-00897-z","url":null,"abstract":"Prostate cancer diagnosis using fast spin-echo (FSE) T2-weight imaging (T2WI) suffers from motion artifacts (T2-MA). We aimed to investigate the risk factors associated with T2-MA. We retrospectively analyzed the basic patient information and localizer images of 168 patients who underwent prostate magnetic resonance imaging at our institution between April 2019 and December 2021. FSE T2WI image quality was classified into Poor, Acceptable, and Excellent groups based on T2-MA severity. Between-group differences were analyzed using the Kruskal-Wallis test, and multinomial logistic regression was used to calculate adjusted odds ratios (ORs) for T2-MA. The bladder area of the Acceptable group was significantly larger than that of the Poor group (P = 0.010). The rectal area was significantly larger in the Poor group than in the Excellent group (P = 0.013). Larger rectal and bladder areas in the localizer image were significant risk factors for severe (OR: 1.136) and mild (OR: 1.032) T2-MA, respectively.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":"582-588"},"PeriodicalIF":1.7,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143674738","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

Predictive models of severe disease in patients with COVID-19 pneumonia at an early stage on CT images using topological properties. 基于拓扑特性的CT图像早期COVID-19肺炎重症预测模型

IF 1.7

Radiological Physics and Technology Pub Date : 2025-06-01 Epub Date: 2025-04-28 DOI: 10.1007/s12194-025-00906-1

Takahiro Iwasaki, Hidetaka Arimura, Shohei Inui, Takumi Kodama, Yun Hao Cui, Kenta Ninomiya, Hideyuki Iwanaga, Toshihiro Hayashi, Osamu Abe

{"title":"Predictive models of severe disease in patients with COVID-19 pneumonia at an early stage on CT images using topological properties.","authors":"Takahiro Iwasaki, Hidetaka Arimura, Shohei Inui, Takumi Kodama, Yun Hao Cui, Kenta Ninomiya, Hideyuki Iwanaga, Toshihiro Hayashi, Osamu Abe","doi":"10.1007/s12194-025-00906-1","DOIUrl":"10.1007/s12194-025-00906-1","url":null,"abstract":"Prediction of severe disease (SVD) in patients with coronavirus disease (COVID-19) pneumonia at an early stage could allow for more appropriate triage and improve patient prognosis. Moreover, the visualization of the topological properties of COVID-19 pneumonia could help clinical physicians describe the reasons for their decisions. We aimed to construct predictive models of SVD in patients with COVID-19 pneumonia at an early stage on computed tomography (CT) images using SVD-specific features that can be visualized on accumulated Betti number (BN) maps. BN maps (b0 and b1 maps) were generated by calculating the BNs within a shifting kernel in a manner similar to a convolution. Accumulated BN maps were constructed by summing BN maps (b0 and b1 maps) derived from a range of multiple-threshold values. Topological features were computed as intrinsic topological properties of COVID-19 pneumonia from the accumulated BN maps. Predictive models of SVD were constructed with two feature selection methods and three machine learning models using nested fivefold cross-validation. The proposed model achieved an area under the receiver-operating characteristic curve of 0.854 and a sensitivity of 0.908 in a test fold. These results suggested that topological image features could characterize COVID-19 pneumonia at an early stage as SVD.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":"534-546"},"PeriodicalIF":1.7,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12103364/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144040515","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

Non-lead flexible composite shields efficiency in decreasing dose in chest CT scan imaging. 无铅柔性复合屏蔽在胸部CT扫描成像中的降剂量效果。

IF 1.7

Radiological Physics and Technology Pub Date : 2025-06-01 Epub Date: 2025-02-25 DOI: 10.1007/s12194-025-00885-3

Mahdi Mansoori Kia, Soheila Refahi, Parinaz Mehnati, Reza Malekzadeh, Aarefeh Jafarzadeh Kohneloo

{"title":"Non-lead flexible composite shields efficiency in decreasing dose in chest CT scan imaging.","authors":"Mahdi Mansoori Kia, Soheila Refahi, Parinaz Mehnati, Reza Malekzadeh, Aarefeh Jafarzadeh Kohneloo","doi":"10.1007/s12194-025-00885-3","DOIUrl":"10.1007/s12194-025-00885-3","url":null,"abstract":"Lead-based radiation shielding used usually in radiology departments is being replaced by non-lead shields due to concerns over toxicity, high weight, and the impossibility of applying it in the imaging field. New studies refer to the use of nanomaterials and lightweight polymer-based composites as an alternative that can solve the problems caused by lead shields. The study aims to develop a flexible composite shield for CT scan imaging and examine its effectiveness in reducing radiation exposure. This study involved the construction of 1 mm thick composite shields used in chest CT scan imaging. The first type consisted of 10% bismuth oxide, the second type consisted of 10% tungsten, the third type consisted of 5% bismuth oxide and 5% tungsten, and 90% of the rest of the structure of all shields was silicone. This study examined the morphological test, tensile strength test, attenuation efficiency, and image quality assessment of these shields. The radiation transmission coefficient for 10% bismuth, 10% tungsten and 5% bismuth-5%tungsten shields was obtained as 0.86, 0.80, and 0.83, respectively. Also, the noise increasing percentage for mentioned shields were 6, 4, and 6%, respectively, compared to the case without a shield. The study found that the 10% tungsten-90% silicone shield is the most effective in reducing radiation exposure due to its K-edge and attenuation coefficients. According to the noise assessment, using these shields does not significantly affect the quality of images.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":"358-365"},"PeriodicalIF":1.7,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143494043","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

Comparison of image quality evaluation methods for magnetic resonance imaging using compressed sensing-sensitivity encoding (CS-SENSE). 压缩感知灵敏度编码（CS-SENSE）磁共振成像图像质量评价方法的比较

IF 1.7

Radiological Physics and Technology Pub Date : 2025-06-01 Epub Date: 2025-05-12 DOI: 10.1007/s12194-025-00911-4

Norikazu Koori, Shohei Yamamoto, Hiroki Kamekawa, Hiraku Fuse, Masato Takahashi, Shin Miyakawa, Kota Sasaki, Reina Naruse, Kenji Yasue, Hiroki Nosaka, Yasuo Takatsu, Kosaku Saotome, Kazuma Kurata

{"title":"Comparison of image quality evaluation methods for magnetic resonance imaging using compressed sensing-sensitivity encoding (CS-SENSE).","authors":"Norikazu Koori, Shohei Yamamoto, Hiroki Kamekawa, Hiraku Fuse, Masato Takahashi, Shin Miyakawa, Kota Sasaki, Reina Naruse, Kenji Yasue, Hiroki Nosaka, Yasuo Takatsu, Kosaku Saotome, Kazuma Kurata","doi":"10.1007/s12194-025-00911-4","DOIUrl":"10.1007/s12194-025-00911-4","url":null,"abstract":"This study aimed to compare the relationship between the quantitative values and visual score of acquired images using the CS-SENSE method. T1-weighted image (T1WI) and T2-weighted image (T2WI) were acquired using a phantom created by a 3D printer. Each quantitative values (signal-to-noise ratio [SNR], contrast-to-noise ratio [CNR], structural similarity [SSIM], and scale-invariant feature transform [SIFT]) and visual evaluation score (VES) were calculated by the acquired images. The correlation coefficients among the calculating quantitative values and VES were calculated. The difference in methods for evaluating the image quality of T1WI and T2WI images using CS-SENSE was clarified. Variations in image quality, as reflected by VES in T1WI and T2WI images obtained via the CS-SENSE method, can be quantitatively assessed. Specifically, CNR is effective for evaluating changes in T1WI, while SNR, CNR, and SIFT are suitable for assessing variations in T2WI.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":"597-605"},"PeriodicalIF":1.7,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144003836","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

Initial demonstration of the Scratch-PET concept: an intraoperative PET with a hand-held detector. 划痕PET概念的初步演示：术中带手持检测器的PET。

IF 1.7

Radiological Physics and Technology Pub Date : 2025-06-01 Epub Date: 2025-03-12 DOI: 10.1007/s12194-025-00889-z

Taiyo Ishikawa, Yuma Iwao, Go Akamatsu, Sodai Takyu, Hideaki Tashima, Takayuki Okamoto, Taiga Yamaya, Hideaki Haneishi

{"title":"Initial demonstration of the Scratch-PET concept: an intraoperative PET with a hand-held detector.","authors":"Taiyo Ishikawa, Yuma Iwao, Go Akamatsu, Sodai Takyu, Hideaki Tashima, Takayuki Okamoto, Taiga Yamaya, Hideaki Haneishi","doi":"10.1007/s12194-025-00889-z","DOIUrl":"10.1007/s12194-025-00889-z","url":null,"abstract":"Positron emission tomography (PET) is a valuable tool for diagnosing malignant tumors. Intraoperative PET imaging is expected to allow the more accurate localization of tumors that need resections. However, conventional devices feature a large detector ring that obstructs surgical procedures, preventing their intraoperative application. This paper proposes a new PET device, Scratch-PET, for image-guided tumor resection. The key feature of Scratch-PET is its use of a hand-held detector to scan the surgical field, ensuring open space for surgery while measuring annihilation radiation with a fixed detector array placed below the patient. We developed a prototype device using two detectors: the hand-held detector and a fixed detector, to demonstrate the feasibility of the proposed concept. Both detectors consisted of 16 × 16 arrays of lutetium yttrium orthosilicates (3 × 3 × 15 mm3) coupled one-to-one with 16 × 16 silicon photomultiplier arrays. The position and orientation of the hand-held detector are tracked using an optical tracking sensor that detects attached markers. We measured a 22Na multi-rod phantom and two 22Na point sources separately for 180 s while moving the hand-held detector. The rod diameters were 6.0, 5.0, 4.0, 3.0, 2.2, and 1.6 mm. Each point source was placed at the field-of-view center and 35 mm off-center which was outside the sensitive area when the hand-held detector was positioned facing the fixed detector. The 2.2 mm rods were partially resolved, and both point sources were successfully visualized. The potential of the proposed device to visualize small tumors was validated.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":"407-416"},"PeriodicalIF":1.7,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12103487/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143617559","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