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Stage IV malignant transformation of mature cystic teratoma palliatively treated with concurrent chemoradiotherapy:A case report
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作者 Saori Kondo Takashi Suzuki +4 位作者 Kanato Yoshiike Sakura Yamanaka Kenta Sonehara Hiroshi Nabeshima Osamu Oguchi 《World Journal of Clinical Cases》 SCIE 2025年第1期56-61,共6页
BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced cases.Concurrent chemoradiotherapy(CCRT)has an inhibitory effect on MT.CASE SUMMARY Herein,we present a ... BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced cases.Concurrent chemoradiotherapy(CCRT)has an inhibitory effect on MT.CASE SUMMARY Herein,we present a case in which CCRT had a reduction effect preoperatively.A 73-year-old woman with pyelonephritis was referred to our hospital.Computed tomography revealed right hydronephrosis and a 6-cm pelvic mass.Endoscopic ultrasound-guided fine-needle biopsy(EUS-FNB)revealed squamous cell carci-noma.The patient was diagnosed with MT of MCT.Due to her poor general con-dition and renal malfunction,we selected CCRT,expecting fewer adverse effects.After CCRT,her performance status improved,and the tumor size was reduced;surgery was performed.Five months postoperatively,the patient developed dis-semination and lymph node metastases.Palliative chemotherapy was ineffective.She died 18 months after treatment initiation.CONCLUSION EUS-FNB was useful in the diagnosis of MT of MCT;CCRT suppressed the disea-se and improved quality of life. 展开更多
关键词 Mature cystic teratoma Malignant transformation Squamous cell carcinoma Concurrent chemoradiotherapy Endoscopic ultrasound-guided fine-needle biopsy Case report
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Development of immature ovarian teratoma after mature teratoma in a girl with familial ovarian teratoma:A case report
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作者 U Chul Ju Woo Dae Kang Seok Mo Kim 《World Journal of Clinical Cases》 SCIE 2024年第8期1442-1447,共6页
BACKGROUND Immature ovarian teratoma is a rare and aggressive neoplasm that affects young women.This report is the first to describe the development of immature teratoma after ovarian cystectomy for mature teratoma of... BACKGROUND Immature ovarian teratoma is a rare and aggressive neoplasm that affects young women.This report is the first to describe the development of immature teratoma after ovarian cystectomy for mature teratoma of the ovary in an adolescent female with a family history of ovarian teratoma.CASE SUMMARY A 16-year-old girl who had undergone bilateral ovarian cystectomy for mature teratomas 3 years ago showed bilateral adnexal tumors during her regular ultrasonography follow-up every 6 months.She received laparoscopic bilateral ovarian cystectomy,and final histopathology showed grade-1 immature teratoma of the left ovary and mature teratoma of the right ovary.Laparoscopic left salpingo-oophorectomy and staging procedures were performed again.Her mother,maternal aunt,and maternal grandmother had also received surgeries for mature ovarian teratomas.CONCLUSION It is important to have guidance on management of patient and family members with familial ovarian teratomas. 展开更多
关键词 Familial ovarian teratomas Adolescent female Immature ovarian teratoma Management Case report
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Monodermal teratoma:Three case reports and review of literature
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作者 Ling-Yu He Wei Li 《World Journal of Clinical Cases》 SCIE 2024年第22期5168-5176,共9页
BACKGROUND The incidence of monodermal teratomas of the reproductive system is low,and most doctors lack adequate understanding,which can easily lead to missed diagnoses and/or misdiagnosis.Therefore,it is important t... BACKGROUND The incidence of monodermal teratomas of the reproductive system is low,and most doctors lack adequate understanding,which can easily lead to missed diagnoses and/or misdiagnosis.Therefore,it is important to fully understand the clinical characteristics,diagnosis,differential diagnosis,and treatment of monodermal teratomas of the reproductive system.CASE SUMMARY Case 1:A 14-year-old boy was admitted to the hospital with a right testicular mass for 1 wk and underwent surgical resection.He was finally diagnosed with right testicular monodermal teratoma with no special postoperative discomfort.Case 2:A 40-year-old woman was admitted to the hospital for uterine abnormalities indicated by ultrasound 20 d prior and underwent laparoscopic surgery.She was finally diagnosed with a left ovarian monodermal teratoma with a satisfactory postoperative quality of life.Case 3:A 49-year-old woman was admitted to the hospital with a pelvic mass that was discovered on B-ultrasound a week prior and underwent laparoscopic resection of the left adnexa.She was finally diagnosed with left ovarian monodermal teratoma,and her postoperative quality of life was satisfactory.CONCLUSION Monodermal teratoma is a rare tumor whose clinical manifestations are primarily benign.Simple surgical resection of the tumor is effective. 展开更多
关键词 teratoma REPRODUCTION OVARY TESTIS Case report
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Adenocarcinoma of sigmoid colon with metastasis to an ovarian mature teratoma: A case report
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作者 Wei Wang Chun-Chi Lin +2 位作者 Wen-Yi Liang Shih-Ching Chang Jeng-Kai Jiang 《World Journal of Clinical Cases》 SCIE 2024年第4期853-858,共6页
BACKGROUND Colorectal cancer ranks third in global cancer-related mortality,often due to metastases to liver and lungs.Ovarian metastases are less common,accounting for 3.6%to 7.4%of cases.In contrast,mature ovarian t... BACKGROUND Colorectal cancer ranks third in global cancer-related mortality,often due to metastases to liver and lungs.Ovarian metastases are less common,accounting for 3.6%to 7.4%of cases.In contrast,mature ovarian teratomas are frequently benign.Tumor-to-tumor metastasis is a rare phenomenon,with a limited number of documented cases.Three cases of mature ovarian teratomas metastasizing from different cancers have been reported.This report focuses on a case of tumor-totumor metastasis from sigmoid colon adenocarcinoma to a mature ovarian teratoma.CASE SUMMARY A 41-year-old Taiwan residents woman with no known systemic diseases presented with lower back pain,which led to imaging revealing malignant lesions in the spine,pelvis,liver,and multiple lung metastases.She was diagnosed with sigmoid colon adenocarcinoma with metastases to the liver,lung,bone,and a left ovarian teratoma.Treatment involved radiotherapy and chemotherapy,resulting in regression of the primary tumor and stable lung and liver lesions.Due to abdominal symptoms,she underwent exploratory surgery,unveiling a mature teratoma in the left ovary with signs of metastatic adenocarcinoma.CONCLUSION Consider resecting mature ovarian teratomas with concurrent colorectal adenocarcinoma to prevent tumor-to-tumor metastasis. 展开更多
关键词 Tumor-to-tumor metastasis Colorectal cancer Ovarian teratoma Adeno carcinoma Case report
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Multi-distortion suppression for neutron radiographic images based on generative adversarial network
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作者 Cheng-Bo Meng Wang-Wei Zhu +4 位作者 Zhen Zhang Zi-Tong Wang Chen-Yi Zhao Shuang Qiao Tian Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第4期176-188,共13页
Neutron radiography is a crucial nondestructive testing technology widely used in the aerospace,military,and nuclear industries.However,because of the physical limitations of neutron sources and collimators,the result... Neutron radiography is a crucial nondestructive testing technology widely used in the aerospace,military,and nuclear industries.However,because of the physical limitations of neutron sources and collimators,the resulting neutron radiographic images inevitably exhibit multiple distortions,including noise,geometric unsharpness,and white spots.Furthermore,these distortions are particularly significant in compact neutron radiography systems with low neutron fluxes.Therefore,in this study,we devised a multi-distortion suppression network that employs a modified generative adversarial network to improve the quality of degraded neutron radiographic images.Real neutron radiographic image datasets with various types and levels of distortion were built for the first time as multi-distortion suppression datasets.Thereafter,the coordinate attention mechanism was incorporated into the backbone network to augment the capability of the proposed network to learn the abstract relationship between ideally clear and degraded images.Extensive experiments were performed;the results show that the proposed method can effectively suppress multiple distortions in real neutron radiographic images and achieve state-of-theart perceptual visual quality,thus demonstrating its application potential in neutron radiography. 展开更多
关键词 Neutron radiography Multi-distortion suppression Generative adversarial network Coordinate attention mechanism
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Deep learning automation of radiographic patterns for hallux valgus diagnosis
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作者 Angela Hussain Cadence Lee +1 位作者 Eric Hu Farid Amirouche 《World Journal of Orthopedics》 2024年第2期105-109,共5页
Artificial intelligence(AI)and deep learning are becoming increasingly powerful tools in diagnostic and radiographic medicine.Deep learning has already been utilized for automated detection of pneumonia from chest rad... Artificial intelligence(AI)and deep learning are becoming increasingly powerful tools in diagnostic and radiographic medicine.Deep learning has already been utilized for automated detection of pneumonia from chest radiographs,diabetic retinopathy,breast cancer,skin carcinoma classification,and metastatic lymphadenopathy detection,with diagnostic reliability akin to medical experts.In the World Journal of Orthopedics article,the authors apply an automated and AIassisted technique to determine the hallux valgus angle(HVA)for assessing HV foot deformity.With the U-net neural network,the authors constructed an algorithm for pattern recognition of HV foot deformity from anteroposterior highresolution radiographs.The performance of the deep learning algorithm was compared to expert clinician manual performance and assessed alongside clinician-clinician variability.The authors found that the AI tool was sufficient in assessing HVA and proposed the system as an instrument to augment clinical efficiency.Though further sophistication is needed to establish automated algorithms for more complicated foot pathologies,this work adds to the growing evidence supporting AI as a powerful diagnostic tool. 展开更多
关键词 Artificial intelligence Hallux valgus Deep learning Automated radiography
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Prenatal ultrasound diagnosis of fetal maxillofacial teratoma:Two case reports
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作者 Chuan-Fen Gao Pei Zhou Chen Zhang 《World Journal of Clinical Oncology》 2024年第9期1245-1250,共6页
BACKGROUND Facial teratoma is a rare benign tumor that accounts for about 1.6%of all teratomas and can be diagnosed by prenatal ultrasound(US).The purpose of this report was to describe our experience with the diagnos... BACKGROUND Facial teratoma is a rare benign tumor that accounts for about 1.6%of all teratomas and can be diagnosed by prenatal ultrasound(US).The purpose of this report was to describe our experience with the diagnosis of fetal facial teratoma by prenatal US at second trimester to provide a reference for clinical diagnosis of fetal maxillofacial teratoma.CASE SUMMARY We present two cases of patients with abnormal fetal facial findings on US at second trimester of pregnancy in our department.Case 1 was a 31-year-old G3 P1+1 female,with US revealing a heterogeneous echogenicity of 32 mm×20 mm×31 mm on the fetal face,most of it located outside the oral cavity and filling the root of the oral cavity.Case 2 was a 29-year-old G1P0 female,with fetal head and neck US revealing a cystic-solid echo mass measuring 42 mm×33 mm×44 mm,the upper edge of the lesion reaching the palate and filling the oral cavity.The contours of the lesions were visualized using three-dimensional(3D)US imaging.Both patients decided to give up treatment.Biopsies of the lesions were performed after induction of labor,and diagnosed as maxillofacial teratoma.CONCLUSION Fetal maxillofacial teratomas can be diagnosed by US in early pregnancy,allowing parents to expedite treatment decisions. 展开更多
关键词 Fetal maxillofacial teratoma Prenatal ultrasound DIAGNOSIS ULTRASOUND Case report
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Radiography Image Classification Using Deep Convolutional Neural Networks
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作者 Ahmad Chowdhury Haiyi Zhang 《Journal of Computer and Communications》 2024年第6期199-209,共11页
Research has shown that chest radiography images of patients with different diseases, such as pneumonia, COVID-19, SARS, pneumothorax, etc., all exhibit some form of abnormality. Several deep learning techniques can b... Research has shown that chest radiography images of patients with different diseases, such as pneumonia, COVID-19, SARS, pneumothorax, etc., all exhibit some form of abnormality. Several deep learning techniques can be used to identify each of these anomalies in the chest x-ray images. Convolutional neural networks (CNNs) have shown great success in the fields of image recognition and image classification since there are numerous large-scale annotated image datasets available. The classification of medical images, particularly radiographic images, remains one of the biggest hurdles in medical diagnosis because of the restricted availability of annotated medical images. However, such difficulty can be solved by utilizing several deep learning strategies, including data augmentation and transfer learning. The aim was to build a model that would detect abnormalities in chest x-ray images with the highest probability. To do that, different models were built with different features. While making a CNN model, one of the main tasks is to tune the model by changing the hyperparameters and layers so that the model gives out good training and testing results. In our case, three different models were built, and finally, the last one gave out the best-predicted results. From that last model, we got 98% training accuracy, 84% validation, and 81% testing accuracy. The reason behind the final model giving out the best evaluation scores is that it was a well-fitted model. There was no overfitting or underfitting issues. Our aim with this project was to make a tool using the CNN model in R language, which will help detect abnormalities in radiography images. The tool will be able to detect diseases such as Pneumonia, Covid-19, Effusions, Infiltration, Pneumothorax, and others. Because of its high accuracy, this research chose to use supervised multi-class classification techniques as well as Convolutional Neural Networks (CNNs) to classify different chest x-ray images. CNNs are extremely efficient and successful at reducing the number of parameters while maintaining the quality of the primary model. CNNs are also trained to recognize the edges of various objects in any batch of images. CNNs automatically discover the relevant aspects in labeled data and learn the distinguishing features for each class by themselves. 展开更多
关键词 CNN radiography Image Classification R Keras Chest X-Ray Machine Learning
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In situ study on columnar-equiaxed transition and anaxial columnar dendrite growth of Al-15%Cu alloy by synchrotron radiography 被引量:3
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作者 李发国 东青 +5 位作者 张佼 戴永兵 付亚楠 谢红兰 尹付成 孙宝德 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第7期2112-2116,共5页
Directional solidification of Al-15% (mass fraction) Cu alloy was investigated by in situ and real time radiography which was performed by Shanghai synchrotron radiation facility (SSRF). The imaging results reveal... Directional solidification of Al-15% (mass fraction) Cu alloy was investigated by in situ and real time radiography which was performed by Shanghai synchrotron radiation facility (SSRF). The imaging results reveal that columnar to equiaxed transition (CET) is provoked by external thermal disturbance. The detaching and floating of fragments of dendrite arms are the prelude of the transition when the solute boundary layer in front of the solid-liquid interface is thin. And the dendrite triangular tip is the fracture sensitive zone. When the conditions are suitable, new dendrites can sprout and grow up. This kind of dendrite has no obvious stem and is named anaxial columnar dendrites. 展开更多
关键词 Al-15%Cu alloy directional solidification columnar to equiaxed transition synchrotron X-ray radiography
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Sacrococcygeal Teratoma
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作者 关键 中山大学附属第一医院医学影像科(图) 《影像诊断与介入放射学》 2019年第1期78-80,共3页
Key Facts Synonyms:Sacrococcygeal teratoma(SGT),germ cell tumor of coccyx Definition:Tumors containing hair,teeth,cartilage,and fat extending from the coccyx and potentially growing both internally and externally.
关键词 SACROCOCCYGEAL teratoma KEY FACTS SYNONYMS DEFINITION
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图像融合技术在Computed Radiography影像中的应用研究
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作者 阮春 李月卿 +3 位作者 王昌元 田庆新 泉向玉 李祥林 《生物医学工程研究》 2002年第1期5-6,共2页
将图像融合技术应用于CR(ComputedRadiography)技术中 ,有效改善影像的信噪比 (signal-to -noiseratio)。运用双IP(ImagePlate)技术采集人体体模影像后 ,在变换域进行图像配准。建立融合图像的数学模型 ,基于此模型对配准完成的源图像... 将图像融合技术应用于CR(ComputedRadiography)技术中 ,有效改善影像的信噪比 (signal-to -noiseratio)。运用双IP(ImagePlate)技术采集人体体模影像后 ,在变换域进行图像配准。建立融合图像的数学模型 ,基于此模型对配准完成的源图像实施不同权重的加权计算得到融合图像。结果 融合图像信噪比源图像可提高 30 %左右。结论 将图像融合技术应用于CR技术可有效改善影像质量 ,有助于提高诊断的准确性。 展开更多
关键词 计算机X线摄影 图像融合 图像配准 信噪比
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Contrast sensitivity in 14 MeV fast neutron radiography 被引量:5
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作者 Chang-Bing Lu Jie Bao +4 位作者 Ying Huang Peng Xu Xiong-Jun Chen Qi-Wei Zhang Xi-Chao Ruan 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第6期115-122,共8页
Fast neutron radiography(FNR) is an effective non-destructive testing technique.Due to the scattering effect and low detection efficiency,the detection limit of FNR under certain conditions cannot be determined.In ord... Fast neutron radiography(FNR) is an effective non-destructive testing technique.Due to the scattering effect and low detection efficiency,the detection limit of FNR under certain conditions cannot be determined.In order to obtain the minimum detectable thickness by FNR,we studied the contrast sensitivity of FNR lead samples,both theoretically and experimentally.We then clarified the relationship between pixel value and irradiation time,and sample materials and thickness.Our experiment,using a4-cm-thick lead sample,verified our theoretical expression of FNR contrast sensitivity. 展开更多
关键词 FAST NEUTRON radiography CONTRAST sensitivity EXPERIMENTAL research
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Reassessment of barium radiographic examination in diagnosing gastrointestinal diseases 被引量:2
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作者 CHEN Jiu-Ru(Zha Bei Central Hospital, 61l9Zhong Hua Xin Road, Shanghai 200070, China) 《World Journal of Gastroenterology》 SCIE CAS CSCD 1999年第5期383-387,共5页
关键词 GASTROINTESTINAL radiography GASTROINTESTINAL diseases/radiography BARIUM RADIOGRAPHIC examination
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Serial imaging of human embryonic stem-cell engraftment and teratoma formation in live mouse models 被引量:9
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作者 Martin G Pomper Holly Hammond +5 位作者 Xiaobing Yu Zhaohui Ye Catherine A Foss Doris D Lin James J Fox Linzhao Cheng 《Cell Research》 SCIE CAS CSCD 2009年第3期370-379,共10页
Two new types of lentiviral vectors expressing a reporter transgene encoding either firefly luciferase (fLuc) for bioluminescence imaging or the HSV1 thymidine kinase (HSV1-TK) for radiopharmaceutical-based imagin... Two new types of lentiviral vectors expressing a reporter transgene encoding either firefly luciferase (fLuc) for bioluminescence imaging or the HSV1 thymidine kinase (HSV1-TK) for radiopharmaceutical-based imaging were constructed to monitor human embryonic stem cell (hESC) engraftment and proliferation in live mice after trans- plantation. The constitutive expression of either transgene did not alter the properties of hESCs in the culture. We next monitored the formation of teratomas in SCID mice to test (1) whether the gene-modified hESCs maintain their developmental pluripotency, and (2) whether sustained reporter gene expression allows noninvasive, whole-body imaging of hESC derivatives in a live mouse model. We observed teratoma formation from both types of gene-modified cells as well as wild-type hESCs 2-4 months after inoculation. Using an optical imaging system, bioluminescence from the fLuc-transduced hESCs was easily detected in mice bearing teratomas long before palpable tumors could be detected. To develop a noninvasive imaging method more readily translatable to the clinic, we also utilized HSV1-TK and its specific substrate, 1-(2'-deoxy-2'-fluoro-β-D-arabinofuranosyl)-5-[^125I]iodouracil([^125I]FIAU), as a reporter/ probe pair. After systemic administration, [^125I]FIAU is phosphorylated only by the transgene-encoded HSV1-TK enzyme and retained within transduced (and transplanted) cells, allowing sensitive and quantitative imaging by single-photon emission computed tomography. Noninvasive imaging methods such as these may enable us to monitor the presence and distribution of transplanted human stem cells repetitively within live recipients over a long term through the expression of a reporter gene. 展开更多
关键词 pluripotent stem cells ESCS optical imaging SPECT PET teratoma
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Digital radiography of crush thoracic trauma in the Sichuan earthquake 被引量:2
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作者 Zhi-Hui Dong Heng Shao +5 位作者 Tian-Wu Chen Zhi-Gang Chu Wen Deng Si-Shi Tang Jing Chen Zhi-Gang Yang 《World Journal of Radiology》 CAS 2011年第11期273-278,共6页
AIM:To investigate the features of crush thoracic trauma in Sichuan earthquake victims using chest digital radiography(CDR).METHODS:We retrospectively reviewed 772 CDR of 417 females and 355 males who had suffered cru... AIM:To investigate the features of crush thoracic trauma in Sichuan earthquake victims using chest digital radiography(CDR).METHODS:We retrospectively reviewed 772 CDR of 417 females and 355 males who had suffered crush thoracic trauma in the Sichuan earthquake.Patient age ranged from 0.5 to 103 years.CDR was performed between May 12,2008 and June 7,2008.We looked for injury to the thoracic cage,pulmonary parenchyma and the pleura.obtained in 349 patients,the remaining 423 patients underwent only AP CDR.Thoracic cage fractures,pulmonary contusion and pleural injuries were noted in 331(42.9%;95% CI:39.4%-46.4%),67 and 135 patients,respectively.Of the 256 patients with rib fractures,the mean number of fractured ribs per patient was 3.Rib fractures were mostly distributed from the 3rd through to the 8th ribs and the vast majority involved posterior and lateral locations along the rib.Rib fractures had a significant positive association with non-rib thoracic fractures,pulmonary contusion and pleural injuries(P < 0.001).The number of rib fractures and pulmonary contusions were significant factors associated with patient death.CONCLUSION:Earthquake-related crush thoracic trauma has the potential for multiple fractures.The high number of fractured ribs and pulmonary contusions were significant factors which needed appropriate medical treatment. 展开更多
关键词 Earthquake PLEURA Pulmonary PARENCHYMA radiography THORACIC TRAUMA
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Comparison of conventional radiography and MDCT in suspected scaphoid fractures 被引量:4
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作者 Cyrus Behzadi Murat Karul +6 位作者 Frank Oliver Henes Azien Laqmani Philipp Catala-Lehnen Wolfgang Lehmann Hans-Dieter Nagel Gerhard Adam Marc Regier 《World Journal of Radiology》 CAS 2015年第1期22-27,共6页
AIM: To determine the diagnostic accuracy and radiation dose of conventional radiography and multidetector computed tomography(MDCT) in suspected scaphoid fractures.METHODS: One hundred twenty-four consecutive patient... AIM: To determine the diagnostic accuracy and radiation dose of conventional radiography and multidetector computed tomography(MDCT) in suspected scaphoid fractures.METHODS: One hundred twenty-four consecutive patients were enrolled in our study who had suffered from a wrist trauma and showed typical clinical symptoms suspicious of an acute scaphoid fracture. All patients had initially undergone conventional radiography. Subsequent MDCT was performed within 10 d because of persisting clinical symptoms. Using the MDCT data as the reference standard, a fourfold table was used to classify the test results. The effective dose and impaired energy were assessed in order to compare the radiation burden of the two techniques. The Wilcoxon test was performed to compare the two diagnostic modalities.RESULTS: Conventional radiography showed 34 acute fractures of the scaphoid in 124 patients(42.2%). Subsequent MDCT revealed a total of 42 scaphoid fractures. The sensitivity of conventional radiography for scaphoid fracture detection was 42.8% and its specificity was 80% resulting in an overall accuracy of 59.6%. Conventional radiography was significantly inferior to MDCT(P < 0.01) concerning scaphoidfracture detection. The mean effective dose of MDCT was 0.1 m Sv compared to 0.002 m Sv of conventional radiography.CONCLUSION: Conventional radiography is insufficient for accurate scaphoid fracture detection. Regarding the almost negligible effective dose, MDCT should serve as the first imaging modality in wrist trauma. 展开更多
关键词 MUSCULOSKELETAL imaging SCAPHOID fracture MULTIDETECTOR computed tomography Biplane radiography Emergency radiology Diagnostic accuracy WRIST trauma Dose calculation
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Resolution analysis of thermal neutron radiography based on accelerator-driven compact neutron source 被引量:7
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作者 Lian-Xin Zhang Si-Ze Chen +6 位作者 Zao-Di Zhang Tao-Sheng Li Chuan Peng Lei Ren Rui Zhang Dan Xiao Yong Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第5期139-151,共13页
Owing to the immobility of traditional reactors and spallation neutron sources,the demand for compact thermal neutron radiography(CTNR)based on accelerator neutron sources has rapidly increased in industrial applicati... Owing to the immobility of traditional reactors and spallation neutron sources,the demand for compact thermal neutron radiography(CTNR)based on accelerator neutron sources has rapidly increased in industrial applications.Recently,thermal neutron radiography experiments based on a D-T neutron generator performed by Hefei Institutes of Physical Science indicated a significant resolution deviation between the experimental results and the values calculated using the traditional resolution model.The experimental result was up to 23%lower than the calculated result,which hinders the achievement of the design goal of a compact neutron radiography system.A GEANT4 Monte Carlo code was developed to simulate the CTNR process,aiming to identify the key factors leading to resolution deviation.The effects of a low collimation ratio and high-energy neutrons were analyzed based on the neutron beam environment of the CTNR system.The results showed that the deviation was primarily caused by geometric distortion at low collimation ratios and radiation noise induced by highenergy neutrons.Additionally,the theoretical model was modified by considering the imaging position and radiation noise factors.The modified theoretical model was in good agreement with the experimental results,and the maximum deviation was reduced to 4.22%.This can be useful for the high-precision design of CTNR systems. 展开更多
关键词 Neutron radiography Spatial resolution Accelerator-driven neutron source GEANT4 MTF ESF
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Primary gastric teratoma on the cardiac orifice in an adult 被引量:3
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作者 Liu Liu Wen Zhuang +2 位作者 Zhong Chen Yong Zhou Xiao-Ran Huang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第14期1782-1785,共4页
Gastric teratoma (GT) is a seldom seen congenital abnormality. GT always occurs in children. The greater curvature and posterior wall of the stomach are the most common sites involving GT. We diagnosed a case of GT lo... Gastric teratoma (GT) is a seldom seen congenital abnormality. GT always occurs in children. The greater curvature and posterior wall of the stomach are the most common sites involving GT. We diagnosed a case of GT located on the inferior wall of the cardiac orifice in a 20-year-old man. To the best of our knowledge, this is the first case of GT located on the wall of the cardiac orifice in an adult in the English literature. We report this unusual case as an addition to this rare disease usually found in children. Computed tomography combined with endoscopic ultrasonography can be selected to diagnose GT. 展开更多
关键词 ADULT Cardiac orifice Endoscopic ultrasonography STOMACH teratoma
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Duodenal mature teratoma causing partial intestinal obstruction:A first case report in an adult 被引量:2
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作者 Tharintorn Chansoon Napat Angkathunyakul +1 位作者 Rangsima Aroonroch Jakrapan Jirasiritham 《World Journal of Clinical Cases》 SCIE 2020年第8期1489-1494,共6页
BACKGROUND A teratoma is a germ cell tumor that is composed of tissue derived from two or three germ layers.Duodenal teratomas are extremely rare and have been exclusively reported in neonates and children.This is the... BACKGROUND A teratoma is a germ cell tumor that is composed of tissue derived from two or three germ layers.Duodenal teratomas are extremely rare and have been exclusively reported in neonates and children.This is the third case of a teratoma primarily arising in the duodenum and the first case that occurred in an adult.CASE SUMMARY A 31-year-old male presented with clinical partial gut obstruction(epigastric pain,nausea,and vomiting).The physical examination showed a palpable illdefined mass on the left side of the abdomen.The computed tomography scan revealed a multiseptated cystic tumor at the retroperitoneal area.First,he underwent gastrojejunostomy to relieve the symptoms and was referred to a tertiary-care hospital.The second operation revealed a 10-cm solid-cystic mass originating from the third part of the duodenum and adhering to the abdominal aorta and pancreas.Segmental duodenectomy was performed.The pathological diagnosis was a mature cystic teratoma.The patient was asymptomatic at 5 mo after the operation.CONCLUSION Duodenal teratomas are extremely rare but should be included in the differential diagnosis in patients who present with intestinal obstruction.Radiological imaging is helpful to reach the preoperative diagnosis.Multidisciplinary team planning is essential to avoid injury to the adjacent organ in duodenal operation. 展开更多
关键词 DUODENAL teratoma Mature CYSTIC teratoma Intestinal OBSTRUCTION GERM cell tumor RETROPERITONEAL mass Case report
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Imaging internal density structure of the Laoheishan volcanic cone with cosmic ray muon radiography 被引量:4
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作者 Ya-Ping Cheng Ran Han +8 位作者 Zhi-Wei Li Jing-Tai Li Xin Mao Wen-Qiang Dou Xin-Zhuo Feng Xiao-Ping Ou-Yang Bin Liao Fang Liu Lei Huang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第7期115-124,共10页
Muon radiography is a promising technique for imaging the internal density structures of targets such as tunnels,pyramids,and volcanoes up to a scale of a few hundred meters by measuring the flux attenuation of cosmic... Muon radiography is a promising technique for imaging the internal density structures of targets such as tunnels,pyramids,and volcanoes up to a scale of a few hundred meters by measuring the flux attenuation of cosmic ray muons after they have traveled through these targets.In this study,we conducted experimental muon radiography of one of the volcanoes in the Wudalianchi area in Northeast China to image its internal density structure.The muon detector used in this study was composed of plastic scintillators and silicon photomultipliers.After approximately one and a half months of observing the crater and conduit of the Laoheishan volcano cone in Wudalianchi from September 23^(rd) to November 10^(th) 2019,more than 3 million muon tracks fulfilling the data selection criteria were collected.Based on the muon samples and high-resolution topography obtained through aerial photogrammetry using an unmanned aerial vehicle,a density image of the Laoheishan volcano cone was constructed.The results obtained in this experiment demonstrate the feasibility of using a radiography technique based on plastic scintillator detectors.To obtain the density distribution,we performed a detailed background analysis and found that low-energy charged particles dominated the background noise.Relatively higher densities were found near the surface of the volcanic cone,whereas relatively lower densities were found near the center of the volcanic cone.The experiment in this study is the first volcano muon tomography study performed in China.Our work provides an important reference for future research. 展开更多
关键词 Muon radiography Muon transmission imaging Density
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