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Radiation Field Preference for Radiographic Anatomical Markers by Radiographers in a University Teaching Hospital in Nigeria
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作者 Thomas Adejoh Sobechukwu Warric Iwene Onwuzu +1 位作者 Flavious Bobuin Nkubli Nwamaka Ikegwuonu 《Open Journal of Radiology》 2014年第3期275-278,共4页
Objective: The work aims to determine the radiographers’ preference between primary and secondary radiation fields for imprinting anatomical markers on radiographs. Methodology: Processed radiographs from the darkroo... Objective: The work aims to determine the radiographers’ preference between primary and secondary radiation fields for imprinting anatomical markers on radiographs. Methodology: Processed radiographs from the darkroom with evidence of radiographic anatomical markings were selected randomly and reviewed using a viewing box, within a 4-week period. The radiation field in which markers were placed was noted for each radiograph. Faintly-appearing and partly coned- off markers were excluded. Simple statistical tools were used to derive central tendency. Result: 623 radiographs were assessed. 89.0% (n = 555) had markers in the primary radiation field while 11.0% (n = 68) were in the secondary radiation field. 98% (n = 611) of markers did not obstruct essential anatomy while 2% (n = 12) did, but the radiographs were neither repeated nor rejected because of the twin reason of reportability and the need to avoid additional radiation dose to patients. Conclusion: Radiographers in the centre preferred the primary radiation field for marker placement to avoid cone-off, cut-off and illegibility which leads to repeat. This, however, does not offer superior advantage to markers placed in secondary radiation field. It is recommended that marker placement preference should be guided by the need for legibility, aesthetics and avoidance of essential anatomy. 展开更多
关键词 Marker Radiation Field RADIOGRAPHS radiographers
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Factors Affecting Compliance towards Radiation Protection Equipment among Radiographers:A Cross Sectional Study
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作者 Ismanto Hafizah Che Hassan Regidor III Dioso 《Journal of Human Physiology》 2019年第2期8-17,共10页
Background:Radiographers were at risk of x-ray radiation.Ministry of Heath of Indonesia made a regulation act no.33 year 2007 to secure radiographers on ionizing radiations by using radiation protection equipment(RPE)... Background:Radiographers were at risk of x-ray radiation.Ministry of Heath of Indonesia made a regulation act no.33 year 2007 to secure radiographers on ionizing radiations by using radiation protection equipment(RPE).Objective:This study identified the factors affecting compliance towards RPE among radiographers and determined the correlation between influencing factors and compliance towards RPEs.Methods:The study conducted a quantitative descriptive-correlational design in a cross sectional approach.A total of 103 radiographers answered the online self administered questionnaires from 9 government hospitals at Jakarta,Indonesia.Results:It was identified that personal factors were the knowledge and motivations while the availability of RPEs and standard operating procedures were environmental factors.The knowledge(p=0.001,r=0.321)and motivations(p=0.018,r=0.232),and availability of RPE(p=0.138,r=0.146)and standard operating procedures(p=0.023,r=0.224)were factors affecting a compliance to RPEs.It was however determined that gender(p=0.251,r=0.113),and place of work(p=0.479,r=0.070)were not correlated to both personal and environmental factors.On the contrary,age(p=0.031,r=0.212),highest educational attainment(p=0.039,r=0.203),years of experience(p=0.001,r=0.336),and training(p=0.001,r=0.341)influenced both personal and environmental factors affecting compliance of radiographers towards RPEs.Findings:It was found that Dr.Cipto Mangunkusumo(p=0.271),Persahabatan(p=0.133),Fatmawati(p=0.357),Otak Nasional(p=0.238),Pasar Rebo(p=0.356),Tarakan(0.255),and Koja(p=0.199)hospitals were not probable to comply towards RPEs.Only Infeksi Sulianti Suroso(p=0.21),and Budhi Asih(p=0.0002)hospitals were most probable to comply towards RPEs. 展开更多
关键词 COMPLIANCE CROSS-SECTIONAL Healthcare radiographers RADIATION protection EQUIPMENT
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Development and psychometric evaluation of the radiographers’ competence scale 被引量:1
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作者 Bodil TAndersson Lennart Christensson +1 位作者 Bengt Fridlund Anders Brostrom 《Open Journal of Nursing》 2012年第2期85-96,共12页
Assessing the competence of registered radiographers’ clinical work is of great importance because of the recent change in nursing focus and rapid technological development. Self-assessment assists radiographers to v... Assessing the competence of registered radiographers’ clinical work is of great importance because of the recent change in nursing focus and rapid technological development. Self-assessment assists radiographers to validate and improve clinical practice by identifying their strengths as well as areas that may need to be developed. The aim of the study was to develop and psychometrically test a specially designed instrument, the Radiographers Competence Scale (RCS). A cross sectional survey was conducted comprising 406 randomly selected radiographers all over Sweden. The study consisted of two phases;the development of the instrument and evaluation of its psychometric properties. The first phase included three steps: 1) construction of the RCS;2) pilot testing of face and content validity;and 3) creation of a web-based 54-item questionnaire for testing the instrument. The second phase comprised psychometric evaluation of construct validity, internal consistency reliability and item reduction. The analysis reduced the initial 54 items of the RCS to 28 items. A logical two-factor solution was identified explaining 53.8% of the total variance. The first factor labelled “Nurse initiated care” explained 31.7% of the total variance. Factor 2 labelled “Technical and radiographic processes” explained 22.1% of the total variance. The scale had good internal consistency reliability, with a Cronbach’s alpha of 0.87. The RCS is a short, easy to administer scale for capturing radiographers’ competence levels and the frequency of using their competence. The scale was found to be valid and reliable. The self-assessment RCS can be used in management, patient safety and quality improvement to enhance the radiographic process. 展开更多
关键词 Competence Scale Instrument Development Management NURSING Psychometric Evaluation RADIOGRAPHER RCS
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Assessment of radiation protection knowledge and practices among radiographers in the central region of Ghana
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作者 Emmanuel Fiagbedzi Philip Nii Gorleku +2 位作者 Savanna Nyarko Adomako Asare Gideon Ackah Ndede 《Radiation Medicine and Protection》 2022年第3期146-151,共6页
Objective:To assess the radiation protection practices and knowledge among radiographers in the central region of Ghana.Methods:A cross-sectional study was carried out among practicing radiographers in three selected ... Objective:To assess the radiation protection practices and knowledge among radiographers in the central region of Ghana.Methods:A cross-sectional study was carried out among practicing radiographers in three selected hospitals.The study was carried out from January to October 2021.A self-administered questionnaire comprising three sections was given out to 20 participants to answer.Data were analyzed statistically using the Statistical Package for Social Sciences(SPSS)version 25.0 and logistic regression analysis.Results:The study revealed that over ninety percent of the radiographers had dosimeters but only 25%wear them always.Adherence to radiation protection measures and practices was found to be generally fairly satisfactory,but was high in the age group 35-45.However,Knowledge of radiation protection practices amongst the radi-ographers was generally high.Working experience of fewer than 5 years(P=0.035)gave a high odds ratio(OR)and was of a significant value in determining the radiation training and courses undertaken by these radiographers.Conclusions:The adherence to radiation protection practices was fairly satisfactory,and the knowledge of radi-ation protection practices was generally high,but that is not enough.There is more room for improvement to ensure knowledge is put into practice to enhance proper safety measures,ensure effective work,and overall reduce the negative effects of ionizing radiation. 展开更多
关键词 RADIOGRAPHER Radiation protection PRACTICES Ionizing radiations
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Non-invasive optical characterization and estimation of Zn porosity in gas tungsten arc welding of Fe–Al joints using CR model and OES measurements
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作者 Sai SRIKAR Tinku KUMAR +1 位作者 Degala Venkata KIRAN Reetesh Kumar GANGWAR 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第11期133-141,共9页
In this study,we employed a non-invasive approach based on the collisional radiative(CR)model and optical emission spectroscopy(OES)measurements for the characterization of gas tungsten arc welding(GTAW)discharge and ... In this study,we employed a non-invasive approach based on the collisional radiative(CR)model and optical emission spectroscopy(OES)measurements for the characterization of gas tungsten arc welding(GTAW)discharge and quantification of Zn-induced porosity during the GTAW process of Fe–Al joints.The OES measurements were recorded as a function of weld current,welding speed,and input waveform.The OES measurements revealed significant line emissions from Zn-I in 460–640 nm and Ar-I in 680–800 nm wavelength ranges in all experimental settings.The OES coupled CR model approach for Zn-I line emission enabled the simultaneous determination of both essential discharge parameters i.e.electron temperature and electron density.Further,these predictions were used to estimate the Zn-induced porosity using OES-actinometry on Zn-I emission lines using Ar as actinometer gas.The OES-actinometry results were in good agreement with porosity data derived from an independent approach,i.e.x-ray radiography images.The current study shows that OES-based techniques can provide an efficient route for real-time monitoring of weld quality and estimate porosity during the GTAW process of dissimilar metal joints. 展开更多
关键词 optical emission spectroscopy collisional radiative model ACTINOMETRY GTAW Fe Al joints Zn vapor porosity radiographic imaging(Some figures may appear in colour only in the online journal)
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Intra-Articular Distal Radius Fracture with Lunate Fossa Rotated and Associated Lesions: Radiologic Analysis
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作者 Issam Ait Hadj Sliman Cesar Tommeh +1 位作者 Frederic Desmoulin André-Pierre Uzel 《Open Journal of Orthopedics》 2023年第4期123-130,共8页
Introduction: Intra-articular distal radial fractures in young patients occur in high energy trauma which can lead to a combination of bone and ligaments lesions. An articular step superior to 2 mm is pejorative, for ... Introduction: Intra-articular distal radial fractures in young patients occur in high energy trauma which can lead to a combination of bone and ligaments lesions. An articular step superior to 2 mm is pejorative, for that an adequate radiologic analysis is necessary accessing to the best surgical treatment. The purpose of our study was to investigate this type of fracture and expose radiologic analysis (radiograph and CT-scan) of bone and ligamentous associated lesions of this specific twisted lunate facet fracture for recognizing it and accessing to the best surgical treatment. Patients and Methods: Seven patients with severely displaced type 4 articular fractures of the distal radius whose wrists had been exposed to violent compression are reported in our series, they are required open treatment for the reduction and fixation of disrupted articular surfaces by using an antero-medial approach which allows direct access to the fragment of the lunate facet and easier visualization of the distal radio-ulnar joint. Results: All the patients were clinically examined with antero-posterior and lateral X ray, completed by a CT scan, all the fractures were type IV according to Melone classification. In all of our seven cases there was a lesion of the distal radioulnar joint (DRUJ) identified in the CT scan. The CT scan allowed us to individualize well the void of the lunate fossa and calculate his exact degree of rotation, which is very important for planning therapeutic management. Discussion: In all of our cases the CT scan was to expose all of the osseous and ligamentous injuries;in the sagittal reconstruction we were able to objectify and calculate the exact degree of the rotation of the lunate fossa fragment;in the frontal reconstruction the void of the lunate fossa is visible and in the axial reconstruction we can determine the incongruence of the distal radio-ulnar joint (DRUJ). Intra-articular involvement has long been recognized as a poor prognostic factor in fractures of the distal radius. However, despite early studies reporting poor results with non operative treatment for these injuries, most authors opposed operative intervention, due to lack of a good radiological analysis and the CT scan;knowledge that a number of studies have shown that inadequate reduction of intra-articular distal radius fractures leads to the development of arthritis. 展开更多
关键词 Articular Fracture Lunate Facet Distal Radio-Ulnar Joint WRIST RADIOGRAPH CT-SCAN
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Transfer learning-based super-resolution in panoramic models for predicting mandibular third molar extraction difficulty: a multi-center study
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作者 Wen Li Yang Li +4 位作者 Xiao-Ling Liu Xiang-Long Zheng Shi-Yu Gao Hui-Min Huangfu Li-Song Lin 《Medical Data Mining》 2023年第4期1-7,共7页
Background:This study aims to predict the extraction difficulty of mandibular third molars based on panoramic images using transfer learning while employing super-resolution(SR)technology to enhance the feasibility an... Background:This study aims to predict the extraction difficulty of mandibular third molars based on panoramic images using transfer learning while employing super-resolution(SR)technology to enhance the feasibility and validity of the prediction.Methods:We reviewed a total of 608 preoperative mandibular third molar panoramic radiographs from two medical facilities:the First Affiliated Hospital of Zhengzhou University(n=509;456 in the training set and 53 in the test set)and the Henan Provincial Dental Hospital(n=99 in the validation set).We conducted a deep-transfer learning network on high-resolution(HR)panoramic radiographs to improve the longitudinal resolution of the images and obtained the SR images.Subsequently,we constructed models named Model-HR and Model-SR using high-dimensional quantitative features extracted through the Least Absolute Shrinkage and Selection Operator method.The models’performances were evaluated using the receiver operating characteristic curve(ROC).To assess the reliability of the model,we compared the results from the test set with those of three dentists.Results:Model-SR outperformed Model-HR(area under the curve(AUC):0.779,sensitivity:85.5%,specificity:60.9%,and accuracy:79.8%vs.AUC:0.753,sensitivity:73.7%,specificity:73.9%,and accuracy:73.7%)in predicting the difficulty of extracting mandibular third molars.Both Model-HR(AUC=0.821,95%CI 0.687–0.956)and Model-SR(AUC=0.963,95%CI 0.921–0.999)demonstrated superior performance compared to expert dentists(highest AUC=0.799,95%CI 0.671–0.927).Conclusions:Model-SR yielded superior predictive performance in determining the difficulty of extracting mandibular third molars when compared with Model-HR and expert dentists’visual assessments. 展开更多
关键词 SUPER-RESOLUTION transfer-learning mandibular third molar extraction difficulty panoramic radiographs
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GE飞天6000型DR安装调试研究 被引量:4
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作者 王官 赵国斌 +3 位作者 王碧涛 高龙虎 苗文贵 焦恒来 《中国医学装备》 2010年第8期34-36,共3页
介绍了DR的工作原理,以及在GE飞天6000型DR的安装和调试过程中的一些体会。
关键词 DR(Digital Radiograph) 安装 调试 曝光
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在过敏 bronchopulmonary 麴菌病的胸 X 光线照相术、计算的 tomographic 表明 被引量:14
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作者 Ritesh Agarwal Ajmal Khan +2 位作者 Mandeep Garg Ashutosh N Aggarwal Dheeraj Gupta 《World Journal of Radiology》 CAS 2012年第4期141-150,共10页
AIM:To investigate the chest radiographic and high resolution computed tomography(HRCT)chest manifestations in glucocorticoid-naive allergic bronchopulmonary aspergillosis(ABPA)patients.METHODS:This is a prospective o... AIM:To investigate the chest radiographic and high resolution computed tomography(HRCT)chest manifestations in glucocorticoid-naive allergic bronchopulmonary aspergillosis(ABPA)patients.METHODS:This is a prospective observational study and includes 60 consecutive glucocorticoid-naive patients with ABPA who underwent chest radiography and HRCT of the chest(1.25 mm every 10 mm)in the routine diagnostic workup for ABPA.RESULTS:Chest radiographs were normal in 50%of cases.Of the remainder,most patients demonstrated permanent findings in the form of parallel line and ring shadows suggesting bronchiectasis.Consolidation was detected in 17 cases but in the majority,the corresponding HRCT chest scan showed mucus-filled bronchiectatic cavities.Chest HRCT was normal in 22 patients,while central bronchiectasis(CB)was demonstrated in the remaining 38 patients.Bronchiectasis extended to the periphery in 33%-43%depending on the criteria used for defining CB.The other findings observed on HRCT were mucoid impaction,centrilobular nodules and high-attenuation mucus in decreasing order of frequency.CONCLUSION:Patients with ABPA can present with normal HRCT chest scans.Central bronchiectasis cannot be considered a characteristic feature of ABPA as peripheral bronchiectasis is commonly observed.Consolidation is an uncommon finding in ABPA. 展开更多
关键词 ALLERGIC BRONCHOPULMONARY ASPERGILLOSIS Chest RADIOGRAPH High resolution COMPUTED TOMOGRAPHY COMPUTED TOMOGRAPHY Aspergillus
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The fragmentation of D-shaped casing filled with explosive under eccentric initiation 被引量:2
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作者 Zhi-wei Guo Guang-yan Huang +1 位作者 Wei Zhu Shun-shan Feng 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2018年第5期417-421,共5页
With the technical development of new warhead designs and improvised explosive device protection,irregular casing filled with explosive has been paid more attention recently. In this paper, we studied the fragmentatio... With the technical development of new warhead designs and improvised explosive device protection,irregular casing filled with explosive has been paid more attention recently. In this paper, we studied the fragmentation of a type of D-shaped casing, which is a common asymmetric casing in the field of warhead design. Based on the radiograph technique, static explosive experiments were conducted with D-shaped casings under four different eccentric initiation ratios to explore their fragmentation. A numerical model was then established to simulate the dynamic response of D-shaped casing filled with explosive. The results of numerical simulation were found to agree well with the experimental data.According to the results of numerical simulation and experimental data, the dynamic responses of Dshaped casing were analyzed. The results of the current work pave way for the innovative design of new warhead and for further studying the dynamic response of asymmetric casing. 展开更多
关键词 D-shaped CASING ECCENTRIC initiation X-ray RADIOGRAPH technique Fragmentation Numerical simulation
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Recent advances in imaging technologies in dentistry 被引量:3
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作者 Naseem Shah Nikhil Bansal Ajay Logani 《World Journal of Radiology》 CAS 2014年第10期794-807,共14页
Dentistry has witnessed tremendous advances in all its branches over the past three decades. With these advances, the need for more precise diagnostic tools,specially imaging methods, have become mandatory.From the si... Dentistry has witnessed tremendous advances in all its branches over the past three decades. With these advances, the need for more precise diagnostic tools,specially imaging methods, have become mandatory.From the simple intra-oral periapical X-rays, advanced imaging techniques like computed tomography, cone beam computed tomography, magnetic resonance imaging and ultrasound have also found place in modern dentistry. Changing from analogue to digital radiography has not only made the process simpler and faster but also made image storage, manipulation(brightness/contrast, image cropping, etc.) and retrieval easier. The three-dimensional imaging has made the complex cranio-facial structures more accessible for examination and early and accurate diagnosis of deep seated lesions. This paper is to review current advances in imaging technology and their uses in different disciplines of dentistry. 展开更多
关键词 DENTAL X-rays INTRAORAL X-rays DENTAL cone beam computed tomography PANORAMIC RADIOGRAPH CEPHALOGRAM
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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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Hip joint center localisation: A biomechanical application to hip arthroplasty population 被引量:3
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作者 Vicky Bouffard Mickael Begon +4 位作者 Annick Champagne Payam Farhadnia Pascal-André Vendittoli Martin Lavigne Franois Prince 《World Journal of Orthopedics》 2012年第8期131-136,共6页
AIM: To determine hip joint center(HJC) location on hip arthroplasty population comparing predictive and functional approaches with radiographic measurements.METHODS: The distance between the HJC and the mid-pelvis wa... AIM: To determine hip joint center(HJC) location on hip arthroplasty population comparing predictive and functional approaches with radiographic measurements.METHODS: The distance between the HJC and the mid-pelvis was calculated and compared between the three approaches. The localisation error between the predictive and functional approach was compared using the radiographic measurements as the reference. The operated leg was compared to the non-operated leg.RESULTS: A significant difference was found for the distance between the HJC and the mid-pelvis when comparing the predictive and functional method. The functional method leads to fewer errors. A statistical difference was found for the localization error between the predictive and functional method. The functional method is twice more precise.CONCLUSION: Although being more individualized, the functional method improves HJC localization and should be used in three-dimensional gait analysis. 展开更多
关键词 HIP ARTHROPLASTY HIP joint CENTER localization Predictive APPROACH Functional APPROACH RADIOGRAPHIC measurements
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Effect of varying computed tomography acquisition and reconstruction parameters on semi-automated clot volume quantification 被引量:3
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作者 Audrey E Kaufman Alison N Pruzan +4 位作者 Ching Hsu Sarayu Ramachandran Adam Jacobi Zahi A Fayad Venkatesh Mani 《World Journal of Radiology》 CAS 2018年第3期24-29,共6页
AIM To examine effects of computed tomography(CT)image acquisition/reconstruction parameters on clot volume quantification in vitro for research method validation purposes.METHODS This study was performed in conforman... AIM To examine effects of computed tomography(CT)image acquisition/reconstruction parameters on clot volume quantification in vitro for research method validation purposes.METHODS This study was performed in conformance with HIPAA and IRB Regulations(March 2015-November 2016).A ten blood clot phantom was designed and scanned on a dual-energy CT scanner(SOMATOM Force,Siemens Healthcare Gm BH,Erlangen,Germany)with varying pitch,iterative reconstruction,energy level and slicethickness.A range of clot and tube sizes were used in an attempt to replicate in vivo emboli found within central and segmental branches of the pulmonary arteries in patients with pulmonary emboli.Clot volume was the measured parameter and was analyzed by a single image analyst using a semi-automated region growing algorithm implemented in the FDA-approved Siemens syngo.via image analysis platform.Mixed model analysis was performed on the data.RESULTS On the acquisition side,the continuous factor of energy showed no statistically significant effect on absolute clot volume quantification(P=0.9898).On the other hand,when considering the fixed factor of pitch,there were statistically significant differences in clot volume quantification(P<0.0001).On the reconstruction side,with the continuous factor of reconstruction slice thickness no statistically significant effect on absolute clot volume quantification was demonstrated(P=0.4500).Also on the reconstruction side,with the fixed factor of using iterative reconstructions there was also no statistically significant effect on absolute clot volume quantification(P=0.3011).In addition,there was excellent R^2 correlation between the scale-measured mass of the clots both with respect to the CT measured volumes and with respect to volumes measure by the water displacement method.CONCLUSION Aside from varying pitch,changing CT acquisition parameters and using iterative reconstructions had no significant impact on clot volume quantification with a semi-automated region growing algorithm. 展开更多
关键词 Computed tomography ANGIOGRAPHY RADIOGRAPHIC phantom COMPUTER-ASSISTED image analysis Pulmonary EMBOLISM THROMBOLYTIC therapy
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Factors influencing the yield of mesenteric angiography in lower gastrointestinal bleed 被引量:2
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作者 Pasteur Rasuli Joseph Doumit +2 位作者 Majdi Boulos Caroline Rizk Gaby Doumit 《World Journal of Radiology》 CAS 2014年第5期218-222,共5页
AIM: To assess if certain triaging rules could be established to optimize the yield of mesenteric angiography. METHODS: Medical records of 101 patients were retrospectively reviewed and parameters relating to age, gen... AIM: To assess if certain triaging rules could be established to optimize the yield of mesenteric angiography. METHODS: Medical records of 101 patients were retrospectively reviewed and parameters relating to age, gender, pulse rate, blood pressure, serum hemoglobin, intensive care unit(ICU) admission, and the number of packed red blood cells(PRBC) transfused in the 12 and 24 h prior to the angiography were tabulated in two groups with positive and negative angiography results. RESULTS: We found no correlation between gender, pulse rate, blood pressure or serum hemoglobin and positivity of the mesenteric angiogram. But patients with positive angiogram were found to be on average 7 years older(73.2 years vs 65.9 years old)(P = 0.02). Angiogram was positive in 39.3 %(11/28) of patientsadmitted in ICU vs 23.2%(17/73) who were admitted elsewhere in the hospital(P = 0.03). In the 12 and 24 h prior to angiography, patients with a positive angiogram received a mean of 2.7 ± 2.3 and 3.3 ± 2.6 units of PRBC s respectively, while patients with a negative angiogram had a mean of 1.6 ± 1.9(P = 0.02) and 2.1 ± 2.6 units(P = 0.04) received respectively in the same period. CONCLUSION: Older age, ICU admission, having received at least 4 units PRBC over 12 h or 5 units over 24 h prior to angiogram are leading indicators for a positive study. 展开更多
关键词 ANGIOGRAPHY Diagnostic use Colon Blood supply RADIOGRAPH Gastrointestinal HEMORRHAGE EMERGENCIES MESENTERIC ARTERIES
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Effective Dose Levels from Computed Tomography of the Head during Contrast Studies in Nigeria 被引量:2
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作者 Thomas Adejoh Nzotta Chukwuemeka Christian +1 位作者 Flavious Bobuin Nkubli Joseph Zira Dlama 《Health》 2015年第8期915-919,共5页
Background: Diagnostic reference levels for a number of common diagnostic radiological examinations against which individual centres could compare their performance have been recommended by relevant international agen... Background: Diagnostic reference levels for a number of common diagnostic radiological examinations against which individual centres could compare their performance have been recommended by relevant international agencies. Due to variations in different populations globally, local and national diagnostic reference levels are more reliable. To the best of our knowledge, no centre-specific study has been carried out and national surveys are not available. Objective: To establish a preliminary local and national diagnostic reference level in Nigeria. Methods: A pro-spective and cross-sectional study involving 30 conscious paediatrics and adult patients referred for head computed tomography scan. They were positioned supine and scanned according to the standard protocol for head computed tomography with manual mA selection. The total dose-length products were recorded at the end of the pre-contrast and post-contrast sequences respectively. The pre-contrast dose was taken into cognizance in the determination of the post-contrast value. The effective dose was established by multiplying the dose-length product by 0.0023 mSv.mGy-1.cm-1, a conversion coefficient for brain tissue adopted from the European Commission. Statistical Package for Social Sciences version 17.0 was used to analyze the data. Results: 30 paediatrics and adult patients of mixed gender participated in the study. Their ages ranged from 1 to 74 years with a mean age of 41.47 ± 23.30 years. The pre-contrast effective dose ranged from 1.93 mSv to 3.32 mSv with mean of 2.56 ± 0.51 mSv and 75th percentile of 3.11 mSv while the post-contrast effective dose ranged from 4.06 mSv to 6.97 mSv with mean of 5.27 ± 0.97 mSv and 75th percentile of 6.13 mSv. The mean effective dose from this work and two other isolated studies was 3.0 mSv. Conclusion: Although our quantified doses are below threshold limits for occupational exposures they are higher than the recommended level for the public. A further optimization of scanning protocols by the radiographers could lower the effective dose for patients undergoing contrast head computed tomography in our centre and in the country. 展开更多
关键词 Effective DOSE Diagnostic Reference Level RADIOGRAPHER COMPUTED Tomography HEAD
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Lung cancer screening-don't forget the chest radiograph 被引量:1
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作者 Johannes Gossner 《World Journal of Radiology》 CAS 2014年第4期116-118,共3页
Lung cancer is a major health burden and early detection only bears the possibility of curative treatment. Screening with computed tomography(CT) recently demonstrated a mortality reduction in selected patients and ha... Lung cancer is a major health burden and early detection only bears the possibility of curative treatment. Screening with computed tomography(CT) recently demonstrated a mortality reduction in selected patients and has been incorporated in clinical guidelines. Problems of screening with CT are the excessive number of false positive findings, costs, radiation burden and from a global point of view shortage of CT capacity. In contrast, chest radiography could be an ideal screening tool in the early detection of lung cancer. It is widely available, easy to perform, cheap, the radiation burden is negligible and there is only a low rate of false positive findings. Large randomized controlled trials could not show a mortality reduction, but different large population-based cohort studies have shown a lung cancer mortality reduction. It has been argued that community-based cohort studies are more closely reflecting the "real world" of everyday medicine. Radiologists should be aware of the found mortality reduction and realize that early detection of lung cancer is possible when reading their daily chest radiographs. Offering a chest radiograph in selected scenarios for the early detection of lung cancer is therefore still justified. 展开更多
关键词 Lung cancer SCREENING MORTALITY Chest radiograph
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Skeletal dysplasias: A radiographic approach and review of common non-lethal skeletal dysplasias 被引量:1
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作者 Ananya Panda Shivanand Gamanagatti +1 位作者 Manisha Jana Arun Kumar Gupta 《World Journal of Radiology》 CAS 2014年第10期808-825,共18页
Skeletal dysplasias are not uncommon entities and a radiologist is likely to encounter a suspected case of dysplasia in his practice. The correct and early diagnosis of dysplasia is important for management of complic... Skeletal dysplasias are not uncommon entities and a radiologist is likely to encounter a suspected case of dysplasia in his practice. The correct and early diagnosis of dysplasia is important for management of complications and for future genetic counselling. While there is an exhaustive classification system on dysplasias, it is important to be familiar with the radiological features of common dysplasias. In this article, we enumerate a radiographic approach to skeletal dysplasias, describe the essential as well as differentiating features of common non-lethal skeletal dysplasias and conclude by presenting working algorithms to either definitively diagnose a particular dysplasia or suggest the most likely differential diagnoses to the referring clinician and thus direct further workup of the patient. 展开更多
关键词 SKELETAL DYSPLASIA Short limb DWARFISM Rhizomelia Radiograph SKELETAL survey Review Spondylopepiphyseal DYSPLASIA Multiple epiphyseal DYSPLASIA ACHONDROPLASIA Algorithm APPROACH
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A Comparison between 2D and 3D Images to Study Maxillary and Mandibular Widths: A Pilot Study 被引量:1
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作者 Ilaf Al Mawaldi Sawsan Tabbaa +1 位作者 C. Brian Preston Mayssa Salti 《Open Journal of Stomatology》 2017年第3期186-196,共11页
The objective of this study is to compare the transverse dimensions of the jaws, obtained from traditional posteroanterior (PA) cephalometric radiographs, and with the similar respective measurements obtained by means... The objective of this study is to compare the transverse dimensions of the jaws, obtained from traditional posteroanterior (PA) cephalometric radiographs, and with the similar respective measurements obtained by means of cone beam computed tomography (CBCT). Data of twelve subjects were selected from the clinical records of Orthodontic Department. All of the subjects had their permanent teeth in occlusion and had good quality regular (2D), and CBCT (3D) images as part of their initial records. Subjects were divided to a posterior cross-bite and non-cross bite groups. The ratio of the maxillary, to mandibular transverse widths was calculated for the sample. In subjects without dental cross-bites the average ratio of the maxillary, to mandibular jaw widths was 0.75 on the standard radiographs and 1.04 on the CBCT scans. In subjects with dental cross-bites the average ratio of these widths was 0.70 on the standard radiographs and 0.9 on the CBCT scans. The ratios of the maxillary, to mandibular widths differ when obtained from conventional cephalometric radiographs as compared to the respective ratios obtained from CBCT scans. Maxillary, to mandibular width ratio is in the order of 1:1 as determined by means of CBCT scans. 展开更多
关键词 Posteroanterior CEPHALOMETRIC (PA) RADIOGRAPH CBCT 2D 3D Transverse JAW Measurements Posterior Cross-Bite
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Higher-Order Statistics for Automatic Weld Defect Detection 被引量:2
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作者 Sara Saber Gamal I. Selim 《Journal of Software Engineering and Applications》 2013年第5期251-258,共8页
Image processing and image analysis are the main aspects for obtaining information from digital image owing to the fact that this techniques give the desired details in most of the applications generally and Non-Destr... Image processing and image analysis are the main aspects for obtaining information from digital image owing to the fact that this techniques give the desired details in most of the applications generally and Non-Destructive testing specifically. This paper presents a proposed method for the automatic detection of weld defects in radiographic images. Firstly, the radiographic images were enhanced using adaptive histogram equalization and are filtered using mean and wiener filters. Secondly, the welding area is selected from the radiography image. Thirdly, the Cepstral features are extracted from the Higher-Order Spectra (Bispectrum and Trispectrum). Finally, neural networks are used for feature matching. The proposed method is tested using 100 radiographic images in the presence of noise and image blurring. Results show that in spite of time consumption, the proposed method yields best results for the automatic detection of weld defects in radiography images when the features were extracted from the Trispectrum of the image. 展开更多
关键词 High Order STATISTICS DEFECT DETECTION RADIOGRAPHIC IMAGES NON-DESTRUCTIVE Testing
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