Effects of dose reduction on the detectability of standardized radiolucent lesions in digital panoramic radiography.

PubMed

Dula, K; Sanderink, G; van der Stelt, P F; Mini, R; Buser, D

1998-08-01

Dose reduction in digital panoramic radiography was studied. Intentional underexposure was performed with the Orthophos DS while six different human mandibles were radiographed. Exposure settings were 69 kV/15 mA (standard), 64 kV/16 mA, and 60 kV/16 mA. Standardized spherical defects, each either 1 or 1.25 mm in diameter, were simulated in 288 of 432 images, and seven observers decided whether defects were present or not. Areas under the receiver operating characteristics curves were calculated. They showed no significant differences in the detectability of the 1-mm defect at 69, 64, or 60 kV. For the 1.25-mm defect, no difference was found between the 69 and 60 kV images, but a statistically significant different detectability was found for 64 kV images in comparison with both 69 and 60 kV images. A dose reduction of up to 43% was ascertained with a Pedo-RT-Humanoid phantom when panoramic radiography was performed at 60 kV/16 mA. The conclusion is that with the Orthophos DS, it seems possible to reduce the dose rate of x-rays without loss of diagnostic quality in the case of radiolucent changes.

Genetic damage in exfoliated cells from oral mucosa of individuals exposed to X-rays during panoramic dental radiographies.

PubMed

Cerqueira, E M M; Gomes-Filho, I S; Trindade, S; Lopes, M A; Passos, J S; Machado-Santelli, G M

2004-08-08

The genotoxic effects of X-ray emitted during dental panoramic radiography were evaluated in exfoliated cells from oral epithelium through a differentiated protocol of the micronucleus test. Thirty-one healthy individuals agreed to participate in this study and were submitted to this procedure for diagnosis purpose after being requested by the dentist. All of them answered a questionnaire before the examination. Cells were obtained from both sides of the cheek by gentle scrapping with a cervical brush, immediately before the exposure and after 10 days. Cytological preparations were stained according to Feulgen-Rossenbeck reaction and analyzed under light and laser scanning confocal microscopies. Micronuclei, nuclear projections (buds and broken eggs) and degenerative nuclear alterations (condensed chromatin, karyolysis and karyorrhexis) were scored. The frequencies of micronuclei, karyolysis and pycnosis were similar before and after exposure (P > 0.90), whereas the condensation of the chromatin and the karyorrhexis increased significantly after exposure (P < 0.0001). In contrast, both bud and broken egg frequencies were significantly higher before the examination (P < 0.005), suggesting that these structures are associated to the normal epithelium differentiation. The results suggest that the X-ray exposure during panoramic dental radiography induces a cytotoxic effect by increasing apoptosis. We also believe that the score of other nuclear alterations in addition to the micronucleus improves the sensitivity of genotoxic effects detection.

Accuracy of vertical height measurements on direct digital panoramic radiographs using posterior mandibular implants and metal balls as reference objects.

PubMed

Vazquez, L; Nizamaldin, Y; Combescure, C; Nedir, R; Bischof, M; Dohan Ehrenfest, D M; Carrel, J-P; Belser, U C

2013-01-01

Conventional panoramic radiography, a widely used radiographic examination tool in implant treatment planning, allows evaluation of the available bone height before inserting posterior mandibular implants. Image distortion and vertical magnification due to projection geometry is well described for rotational panoramic radiographs. To assess the accuracy of vertical height measurements on direct digital panoramic radiographs, implants and metal balls positioned in the posterior mandible were used as radio-opaque reference objects. The reproducibility of the measuring method was assessed by the inter- and intraobserver agreements. Direct digital panoramic radiographs, performed using a Kodak 8000C (Eastman Kodak Company, Rochester, NY), of 17 partially edentulous patients (10 females, 7 males, mean age 65 years) were selected from an X-ray database gathered during routine clinical evaluation of implant sites. Proprietary software and a mouse-driven calliper were used to measure the radiological length of 25 implants and 18 metal reference balls, positioned in mandibular posterior segments. The distortion ratio (DR) was calculated by dividing the radiological implant length by the implant's real length and the radiological ball height by the ball's real height. Mean vertical DR was 0.99 for implants and 0.97 for balls, and was unrelated to mandibular sites, side, age, gender or observer. Inter- and intraobserver agreements were acceptable for both reference objects. Vertical measurements had acceptable accuracy and reproducibility when a software-based calibrated measurement tool was used, confirming that digital panoramic radiography can be reliably utilized to determine the pre-operative implant length in premolar and molar mandibular segments.

A new bite block for panoramic radiographs of anterior edentulous patients: A technical report.

PubMed

Park, Jong-Woong; Symkhampha, Khanthaly; Huh, Kyung-Hoe; Yi, Won-Jin; Heo, Min-Suk; Lee, Sam-Sun; Choi, Soon-Chul

2015-06-01

Panoramic radiographs taken using conventional chin-support devices have often presented problems with positioning accuracy and reproducibility. The aim of this report was to propose a new bite block for panoramic radiographs of anterior edentulous patients that better addresses these two issues. A new panoramic radiography bite block similar to the bite block for dentulous patients was developed to enable proper positioning stability for edentulous patients. The new bite block was designed and implemented in light of previous studies. The height of the new bite block was 18 mm and to compensate for the horizontal edentulous space, its horizontal width was 7 mm. The panoramic radiographs using the new bite block were compared with those using the conventional chin-support device. Panoramic radiographs taken with the new bite block showed better stability and bilateral symmetry than those taken with the conventional chin-support device. Patients also showed less movement and more stable positioning during panoramic radiography with the new bite block. Conventional errors in panoramic radiographs of edentulous patients could be caused by unreliability of the chin-support device. The newly proposed bite block for panoramic radiographs of edentulous patients showed better reliability. Further study is required to evaluate the image quality and reproducibility of images with the new bite block.

Comparison of Dental Panoramic Radiography and CBCT for Measuring Vertical Bone Height in Different Horizontal Locations of Posterior Mandibular Alveolar Process.

PubMed

Shahidi, Shoaleh; Zamiri, Barbad; Abolvardi, Masoud; Akhlaghian, Marzieh; Paknahad, Maryam

2018-06-01

Accurate measurement of the available bone height is an essential step in the pre-surgical phase of dental implantation. Panoramic radiography is a unique technique in the pre-surgical phase of dental implantations because of its low cost, relatively low-dose, and availability. This article aimed to assess the reliability of dental panoramic radiographs in the accurate measurement of the vertical bone height with respect to the horizontal location of the alveolar crest. 132 cone-beam computed tomography (CBCT) of the edentulous mandibular molar area and dental panoramic radiograph of 508 patients were selected. Exclusion criteria were bone abnormalities and detectable ideal information on each modality. The alveolar ridge morphology was categorized into 7 types according to the relative horizontal location of the alveolar crest to the mandibular canal based on CBCT findings. The available bone height (ABH) was defined as the distance between the upper border of the mandibular canal and alveolar crest. One oral radiologist and one oral surgeon measured the available bone height twice on each modality with a 7-dayinterval. We found a significant correlation between dental panoramic radiographs and cone-beam computed tomography values (ICC=0.992, p < 0.001). A positive correlation between the horizontal distance of the alveolar crest to the mandibular canal and measured differences between two radiographic modalities had been found (r=0.755, p < 0.001). For each single unit of increase in the horizontal distance of the alveolar crest to the mandibular canal, dental panoramic radiographs showed 0.87 unit of overestimation ( p < 0.001). Dental panoramic radiographs can be employed safely in the pre-surgical phase of dental implantation in posterior alveolus of mandible, especially in routine and simple cases.

Comparison of Dental Panoramic Radiography and CBCT for Measuring Vertical Bone Height in Different Horizontal Locations of Posterior Mandibular Alveolar Process

PubMed Central

Shahidi, Shoaleh; Zamiri, Barbad; Abolvardi, Masoud; Akhlaghian, Marzieh; Paknahad, Maryam

2018-01-01

Statement of the Problem: Accurate measurement of the available bone height is an essential step in the pre-surgical phase of dental implantation. Panoramic radiography is a unique technique in the pre-surgical phase of dental implantations because of its low cost, relatively low-dose, and availability. Purpose: This article aimed to assess the reliability of dental panoramic radiographs in the accurate measurement of the vertical bone height with respect to the horizontal location of the alveolar crest. Materials and Method: 132 cone-beam computed tomography (CBCT) of the edentulous mandibular molar area and dental panoramic radiograph of 508 patients were selected. Exclusion criteria were bone abnormalities and detectable ideal information on each modality. The alveolar ridge morphology was categorized into 7 types according to the relative horizontal location of the alveolar crest to the mandibular canal based on CBCT findings. The available bone height (ABH) was defined as the distance between the upper border of the mandibular canal and alveolar crest. One oral radiologist and one oral surgeon measured the available bone height twice on each modality with a 7-dayinterval. Results: We found a significant correlation between dental panoramic radiographs and cone-beam computed tomography values (ICC=0.992, p< 0.001). A positive correlation between the horizontal distance of the alveolar crest to the mandibular canal and measured differences between two radiographic modalities had been found (r=0.755, p< 0.001). For each single unit of increase in the horizontal distance of the alveolar crest to the mandibular canal, dental panoramic radiographs showed 0.87 unit of overestimation (p< 0.001). Conclusion: Dental panoramic radiographs can be employed safely in the pre-surgical phase of dental implantation in posterior alveolus of mandible, especially in routine and simple cases. PMID:29854881

External root resorption of the second molar associated with third molar impaction: comparison of panoramic radiography and cone beam computed tomography.

PubMed

Oenning, Anne Caroline Costa; Neves, Frederico Sampaio; Alencar, Phillipe Nogueira Barbosa; Prado, Rodrigo Freire; Groppo, Francisco Carlos; Haiter-Neto, Francisco

2014-08-01

The aim of the present study was to compare panoramic radiography and cone beam computed tomography (CBCT) for the assessment of external root resorption (ERR) of second molars associated with impacted third molars. In addition, the prevalence of ERR in second molars and the inclinations of the third molars more associated with ERR were investigated in both imaging methods. The sample consisted of 66 individuals with maxillary and mandibular impacted third molars (n = 188) seen on panoramic radiographs and CBCT images. The presence of ERR on the adjacent second molar was investigated, and the position of the third molar was determined using Winter's classification (vertical, horizontal, mesioangular, distoangular, and transverse). Statistical analysis was performed using the χ(2) test, Fisher exact test, and 2-proportion Z test (the significance level was set at 5%). A significantly greater number of cases of ERR (P < .0001) was diagnosed from CBCT images (n = 43, 22.88%) than panoramic radiographs (n = 10, 5.31%). The agreement between the panoramic radiographs and CBCT scans for diagnosing ERR was 4.3%. Mandibular third molars in mesioangular and horizontal inclinations were more likely to cause resorption of the adjacent teeth. CBCT should be indicated for the diagnosis of ERR in second molars when direct contact between the mandibular second and third molars has been observed on panoramic radiographs, especially in mesioangular or horizontal impactions. Furthermore, considering the propensity of these teeth to cause ERR in second molars, third molar prophylactic extraction could be suggested. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Clinical image quality evaluation for panoramic radiography in Korean dental clinics

PubMed Central

Choi, Bo-Ram; Choi, Da-Hye; Huh, Kyung-Hoe; Yi, Won-Jin; Heo, Min-Suk; Choi, Soon-Chul; Bae, Kwang-Hak

2012-01-01

Purpose The purpose of this study was to investigate the level of clinical image quality of panoramic radiographs and to analyze the parameters that influence the overall image quality. Materials and Methods Korean dental clinics were asked to provide three randomly selected panoramic radiographs. An oral and maxillofacial radiology specialist evaluated those images using our self-developed Clinical Image Quality Evaluation Chart. Three evaluators classified the overall image quality of the panoramic radiographs and evaluated the causes of imaging errors. Results A total of 297 panoramic radiographs were collected from 99 dental hospitals and clinics. The mean of the scores according to the Clinical Image Quality Evaluation Chart was 79.9. In the classification of the overall image quality, 17 images were deemed 'optimal for obtaining diagnostic information,' 153 were 'adequate for diagnosis,' 109 were 'poor but diagnosable,' and nine were 'unrecognizable and too poor for diagnosis'. The results of the analysis of the causes of the errors in all the images are as follows: 139 errors in the positioning, 135 in the processing, 50 from the radiographic unit, and 13 due to anatomic abnormality. Conclusion Panoramic radiographs taken at local dental clinics generally have a normal or higher-level image quality. Principal factors affecting image quality were positioning of the patient and image density, sharpness, and contrast. Therefore, when images are taken, the patient position should be adjusted with great care. Also, standardizing objective criteria of image density, sharpness, and contrast is required to evaluate image quality effectively. PMID:23071969

A study to determine the added value of 740 screening panoramic radiographs compared to intraoral radiography in the management of adult (>18 years) dentate patients in a primary care setting.

PubMed

Rushton, Michael N; Rushton, Vivian E

2012-08-01

To measure the added value of panoramic radiography in new dentate patients attending for routine treatment. Thirty-seven general dental practitioners using panoramic radiographs routinely were recruited. Twenty dentate patients were identified prospectively by each participating dentist if they were new to the practice, attending for an examination and requesting any treatment deemed necessary. A panoramic radiograph was taken with appropriate intraoral radiographs in line with national guidelines. Each dentist completed a radiological report for the panoramic radiograph only and these 20 reports were forwarded to the researchers along with the 20 panoramic radiographs, their accompanying bitewing and periapical radiographs and twenty completed clinical assessment sheets. 740 panoramic, 1418 bitewing and 325 periapical radiographs were assessed by the researchers. Only 32 panoramic films provided any additional diagnostic value when compared to intraoral films when guidelines had been observed resulting from the poor technical and processing quality of the accompanying intraoral films. Assessment of the number of caries and periapical lesions and the degree of periodontal bone loss from the intraoral films provided a greater diagnostic yield at the p<0.001 level of significance. The research found that dentists underestimated the number of caries lesions present and level of periodontal bone loss when compared to the researchers but overestimated the presence of periapical pathology, at the level of significance at p<0.001. The study found that there was no support for the use of panoramic radiographs in routine screening as there was no net diagnostic benefit to the patient. Copyright © 2012 Elsevier Ltd. All rights reserved.

Comparison between DICOM-calibrated and uncalibrated consumer grade and 6-MP displays under different lighting conditions in panoramic radiography

PubMed Central

Haapea, M; Liukkonen, E; Huumonen, S; Tervonen, O; Nieminen, M T

2015-01-01

Objectives: To compare observer performance in the detection of anatomical structures and pathology in panoramic radiographs using consumer grade with and without digital imaging and communication in medicine (DICOM)-calibration and 6-megapixel (6-MP) displays under different lighting conditions. Methods: 30 panoramic radiographs were randomly evaluated on three displays under bright (510 lx) and dim (16 lx) ambient lighting by two observers with different years of experience. Dentinoenamel junction, dentinal caries and periapical inflammatory lesions, visibility of cortical border of the floor and pathological lesions in maxillary sinus were evaluated. Consensus between the observers was considered as reference. Intraobserver agreement was determined. Proportion of equivalent ratings and weighted kappa were used to assess reliability. The level of significance was set to p < 0.05. Results: The proportion of equivalent ratings with consensus differed between uncalibrated and DICOM-calibrated consumer grade displays in dentinal caries in the lower molar in dim lighting (p = 0.021) and between DICOM-calibrated consumer grade and 6-MP display in bright lighting (p = 0.038) for an experienced observer. Significant differences were found between uncalibrated and DICOM-calibrated consumer grade displays in dentinal caries in bright lighting (p = 0.044) and periapical lesions in the upper molar in dim lighting (p = 0.008) for a less experienced observer. Intraobserver reliability was better at detecting dentinal caries than at detecting periapical and maxillary sinus pathology. Conclusions: DICOM calibration may improve observer performance in panoramic radiography in different lighting conditions. Therefore, a DICOM-calibrated consumer grade display can be used instead of a medical display in dental practice without compromising the diagnostic quality. PMID:25564888

The prognostic value of panoramic radiography of inferior alveolar nerve damage after mandibular third molar removal: retrospective study of 400 cases.

PubMed

Szalma, József; Lempel, Edina; Jeges, Sára; Szabó, Gyula; Olasz, Lajos

2010-02-01

The aim of the study was to estimate the accuracy of panoramic radiographic signs predicting inferior alveolar nerve (IAN) paresthesia after lower third molar removal. In a case-control study the sample was composed of 41 cases with postoperative IAN paresthesia and 359 control cases without it. The collected data included "classic" specific signs indicating a close spatial relationship between third molar root and inferior alveolar canal (IAC), root curvatures, and the extent of IAC-root tip overlap. Bivariate and multivariate logistic regression analyses were completed to estimate the association between radiographic findings and IAN paresthesia. The multivariate logistic analysis identified 3 signs significantly associated with IAN paresthesia (P < .001): interruption of the superior cortex of the canal wall, diversion of the canal, and darkening of the root. The sensitivities and specificities ranged from 14.6% to 68.3% and from 85.5% to 96.9%, respectively. The positive predictive values, calculated to factor a 1.1% prevalence of paresthesia, ranged from 3.6% to 10.9%, whereas the negative predictive values >99%. Panoramic radiography is an inadequate screening method for predicting IAN paresthesia after mandibular third molar removal. Copyright (c) 2010 Mosby, Inc. All rights reserved.

Comparative adoption of cone beam computed tomography and panoramic radiography machines across Australia.

PubMed

Zhang, A; Critchley, S; Monsour, P A

2016-12-01

The aim of the present study was to assess the current adoption of cone beam computed tomography (CBCT) and panoramic radiography (PR) machines across Australia. Information regarding registered CBCT and PR machines was obtained from radiation regulators across Australia. The number of X-ray machines was correlated with the population size, the number of dentists, and the gross state product (GSP) per capita, to determine the best fitting regression model(s). In 2014, there were 232 CBCT and 1681 PR machines registered in Australia. Based on absolute counts, Queensland had the largest number of CBCT and PR machines whereas the Northern Territory had the smallest number. However, when based on accessibility in terms of the population size and the number of dentists, the Australian Capital Territory had the most CBCT machines and Western Australia had the most PR machines. The number of X-ray machines correlated strongly with both the population size and the number of dentists, but not with the GSP per capita. In 2014, the ratio of PR to CBCT machines was approximately 7:1. Projected increases in either the population size or the number of dentists could positively impact on the adoption of PR and CBCT machines in Australia. © 2016 Australian Dental Association.

Automatic segmentation of mandible in panoramic x-ray.

PubMed

Abdi, Amir Hossein; Kasaei, Shohreh; Mehdizadeh, Mojdeh

2015-10-01

As the panoramic x-ray is the most common extraoral radiography in dentistry, segmentation of its anatomical structures facilitates diagnosis and registration of dental records. This study presents a fast and accurate method for automatic segmentation of mandible in panoramic x-rays. In the proposed four-step algorithm, a superior border is extracted through horizontal integral projections. A modified Canny edge detector accompanied by morphological operators extracts the inferior border of the mandible body. The exterior borders of ramuses are extracted through a contour tracing method based on the average model of mandible. The best-matched template is fetched from the atlas of mandibles to complete the contour of left and right processes. The algorithm was tested on a set of 95 panoramic x-rays. Evaluating the results against manual segmentations of three expert dentists showed that the method is robust. It achieved an average performance of [Formula: see text] in Dice similarity, specificity, and sensitivity.

Panoramic thermal imaging: challenges and tradeoffs

NASA Astrophysics Data System (ADS)

Aburmad, Shimon

2014-06-01

Over the past decade, we have witnessed a growing demand for electro-optical systems that can provide continuous 3600 coverage. Applications such as perimeter security, autonomous vehicles, and military warning systems are a few of the most common applications for panoramic imaging. There are several different technological approaches for achieving panoramic imaging. Solutions based on rotating elements do not provide continuous coverage as there is a time lag between updates. Continuous panoramic solutions either use "stitched" images from multiple adjacent sensors, or sophisticated optical designs which warp a panoramic view onto a single sensor. When dealing with panoramic imaging in the visible spectrum, high volume production and advancement of semiconductor technology has enabled the use of CMOS/CCD image sensors with a huge number of pixels, small pixel dimensions, and low cost devices. However, in the infrared spectrum, the growth of detector pixel counts, pixel size reduction, and cost reduction is taking place at a slower rate due to the complexity of the technology and limitations caused by the laws of physics. In this work, we will explore the challenges involved in achieving 3600 panoramic thermal imaging, and will analyze aspects such as spatial resolution, FOV, data complexity, FPA utilization, system complexity, coverage and cost of the different solutions. We will provide illustrations, calculations, and tradeoffs between three solutions evaluated by Opgal: A unique 3600 lens design using an LWIR XGA detector, stitching of three adjacent LWIR sensors equipped with a low distortion 1200 lens, and a fisheye lens with a HFOV of 180º and an XGA sensor.

Implant treatment planning regarding augmentation procedures: panoramic radiographs vs. cone beam computed tomography images.

PubMed

Dagassan-Berndt, Dorothea C; Zitzmann, Nicola U; Walter, Clemens; Schulze, Ralf K W

2016-08-01

To evaluate the impact of cone beam computed tomography (CBCT) imaging on treatment planning regarding augmentation procedures for implant placement. Panoramic radiographs and CBCT images of 40 patients requesting single-tooth implants in 59 sites were retrospectively analyzed by six specialists in implantology, and treatment planning was performed. Therapeutic recommendations were compared with the surgical protocol performed initially. Bone height estimation from panoramic radiographs yielded to higher measures and greater variability compared to CBCT. The suggested treatment plan for lateral and vertical augmentation procedures based on CBCT or panoramic radiographs coincided for 55-72% of the cases. A trend to a more invasive augmentation procedure was seen when planning was based on CBCT. Panoramic radiography revealed 57-63% (lateral) vs. 67% (vertical augmentation) congruent plans in agreement with surgery. Among the dissenting sites, there was a trend toward less invasive planning for lateral augmentation with panoramic radiographs, while vertical augmentation requirements were more frequently more invasive when based on CBCT. Vertical augmentation requirements can be adequately determined from panoramic radiographs. In difficult cases with a deficient lateral alveolar bone, the augmentation schedule may better be evaluated from CBCT to avoid underestimation, which occurs more frequently when based on panoramic radiographs only. However, overall, radiographic interpretation and diagnostic thinking accuracy seem to be mainly depending on the opinion of observers. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The influence of dental implants in periapical and panoramic radiographs and cone beam computed tomography images: a clinical study.

PubMed

Felix, Rafael Perdomo; Shinkai, Rosemary Sadami Arai; Rockenbach, Maria Ivete Bolzan

2018-01-01

The aim of this study was to analyze the influence of dental implants on the radiographic density of the peri-implant region in tomographic and radiographic examinations. A sample of 21 dental implants from 10 patients with Brånemark-protocol prostheses was evaluated based on postoperative control images, including periapical radiography (paralleling technique), panoramic radiography, and cone beam computed tomography (CBCT). The density means of 6 defined areas near dental implants were calculated and compared considering their locations and the different imaging examinations. The CBCT examinations showed significantly different densities among the measured areas (P < 0.001), while there were no significant differences among the density means of the various areas in periapical radiographs (P = 0.430) and panoramic radiographs (P = 0.149). The highest mean densities were observed in areas closer to the implants in all the examinations: CBCT (127.88 and 120.71), panoramic (106.51 and 106.09), and periapical (120.32). The sagittal CBCT images were measured in 2 different sections, and in both sections those areas closer to implants showed mean densities that were significantly higher than means from more distant areas (P < 0.001). Means from distant areas on CBCT slice imaging were significantly lower than the densities of the same areas on periapical and panoramic examinations. The changes in mean radiographic density values in the peri-implant region confirmed the interference of dental implants in radiographic and tomographic images. CBCT images suffered the greatest interference from dental implants.

Research and implementation of the algorithm for unwrapped and distortion correction basing on CORDIC for panoramic image

NASA Astrophysics Data System (ADS)

Zhang, Zhenhai; Li, Kejie; Wu, Xiaobing; Zhang, Shujiang

2008-03-01

The unwrapped and correcting algorithm based on Coordinate Rotation Digital Computer (CORDIC) and bilinear interpolation algorithm was presented in this paper, with the purpose of processing dynamic panoramic annular image. An original annular panoramic image captured by panoramic annular lens (PAL) can be unwrapped and corrected to conventional rectangular image without distortion, which is much more coincident with people's vision. The algorithm for panoramic image processing is modeled by VHDL and implemented in FPGA. The experimental results show that the proposed panoramic image algorithm for unwrapped and distortion correction has the lower computation complexity and the architecture for dynamic panoramic image processing has lower hardware cost and power consumption. And the proposed algorithm is valid.

Correlation of calcified carotid plaques detected by panoramic radiograph with risk factors for stroke development.

PubMed

Griniatsos, John; Damaskos, Spyros; Tsekouras, Nikolaos; Klonaris, Chris; Georgopoulos, Sotirios

2009-10-01

The aim was to evaluate whether patients with calcifications in the carotid region detectable by panoramic radiograph differ in the prevalence of risk factors for stroke development compared with those without calcifications. Forty consecutive individuals suffering from proven carotid artery atherosclerotic occlusive disease were submitted to carotid endarterectomy. Seventeen patients were symptomatic at the time of referral, having suffered at least 1 episode of ischemic cerebral event during the preceding 6 months, mainly transient ischemic attacks or amaurosis fugax, and the remaining 23 patients were asymptomatic and the diagnosis was reached during a thorough investigation of coexisting coronary or peripheral vascular disease. Preoperatively, all patients had undergone panoramic radiograph examination, as the presurgical protocol commanded. Based on the panoramic radiograph results, patients in whom calcifications were detected either unilaterally (n = 10) or bilaterally (n = 18) constituted group A (n = 28) and patients in whom no calcifications were detected constituted group B (n = 12) of this study. Univariate analysis among several risk factors for stroke development between the 2 groups of patients disclosed a stastistically significant lower incidence of diabetes mellitus (P = .005) but a higher incidence of symptomatic plaques (P < .030) in the group of patients with detectable calcifications in the panoramic radiograph. Patients with calcified carotid plaques detectable by panoramic radiography are more likely to have suffered cerebrovascular events. Therefore, patients with detectable carotid plaque in panoramic radiographs require referral to their physician for further investigation.

Panoramic cone beam computed tomography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chang Jenghwa; Zhou Lili; Wang Song

2012-05-15

Purpose: Cone-beam computed tomography (CBCT) is the main imaging tool for image-guided radiotherapy but its functionality is limited by a small imaging volume and restricted image position (imaged at the central instead of the treatment position for peripheral lesions to avoid collisions). In this paper, the authors present the concept of ''panoramic CBCT,'' which can image patients at the treatment position with an imaging volume as large as practically needed. Methods: In this novel panoramic CBCT technique, the target is scanned sequentially from multiple view angles. For each view angle, a half scan (180 deg. + {theta}{sub cone} where {theta}{submore » cone} is the cone angle) is performed with the imaging panel positioned in any location along the beam path. The panoramic projection images of all views for the same gantry angle are then stitched together with the direct image stitching method (i.e., according to the reported imaging position) and full-fan, half-scan CBCT reconstruction is performed using the stitched projection images. To validate this imaging technique, the authors simulated cone-beam projection images of the Mathematical Cardiac Torso (MCAT) thorax phantom for three panoramic views. Gaps, repeated/missing columns, and different exposure levels were introduced between adjacent views to simulate imperfect image stitching due to uncertainties in imaging position or output fluctuation. A modified simultaneous algebraic reconstruction technique (modified SART) was developed to reconstruct CBCT images directly from the stitched projection images. As a gold standard, full-fan, full-scan (360 deg. gantry rotation) CBCT reconstructions were also performed using projection images of one imaging panel large enough to encompass the target. Contrast-to-noise ratio (CNR) and geometric distortion were evaluated to quantify the quality of reconstructed images. Monte Carlo simulations were performed to evaluate the effect of scattering on the image

Automatic registration of panoramic image sequence and mobile laser scanning data using semantic features

NASA Astrophysics Data System (ADS)

Li, Jianping; Yang, Bisheng; Chen, Chi; Huang, Ronggang; Dong, Zhen; Xiao, Wen

2018-02-01

Inaccurate exterior orientation parameters (EoPs) between sensors obtained by pre-calibration leads to failure of registration between panoramic image sequence and mobile laser scanning data. To address this challenge, this paper proposes an automatic registration method based on semantic features extracted from panoramic images and point clouds. Firstly, accurate rotation parameters between the panoramic camera and the laser scanner are estimated using GPS and IMU aided structure from motion (SfM). The initial EoPs of panoramic images are obtained at the same time. Secondly, vehicles in panoramic images are extracted by the Faster-RCNN as candidate primitives to be matched with potential corresponding primitives in point clouds according to the initial EoPs. Finally, translation between the panoramic camera and the laser scanner is refined by maximizing the overlapping area of corresponding primitive pairs based on the Particle Swarm Optimization (PSO), resulting in a finer registration between panoramic image sequences and point clouds. Two challenging urban scenes were experimented to assess the proposed method, and the final registration errors of these two scenes were both less than three pixels, which demonstrates a high level of automation, robustness and accuracy.

Relative Panoramic Camera Position Estimation for Image-Based Virtual Reality Networks in Indoor Environments

NASA Astrophysics Data System (ADS)

Nakagawa, M.; Akano, K.; Kobayashi, T.; Sekiguchi, Y.

2017-09-01

Image-based virtual reality (VR) is a virtual space generated with panoramic images projected onto a primitive model. In imagebased VR, realistic VR scenes can be generated with lower rendering cost, and network data can be described as relationships among VR scenes. The camera network data are generated manually or by an automated procedure using camera position and rotation data. When panoramic images are acquired in indoor environments, network data should be generated without Global Navigation Satellite Systems (GNSS) positioning data. Thus, we focused on image-based VR generation using a panoramic camera in indoor environments. We propose a methodology to automate network data generation using panoramic images for an image-based VR space. We verified and evaluated our methodology through five experiments in indoor environments, including a corridor, elevator hall, room, and stairs. We confirmed that our methodology can automatically reconstruct network data using panoramic images for image-based VR in indoor environments without GNSS position data.

Characteristic findings on panoramic radiography and cone-beam CT to predict paresthesia after extraction of impacted third molar.

PubMed

Harada, Nana; Beloor Vasudeva, Subash; Matsuda, Yukiko; Seki, Kenji; Kapila, Rishabh; Ishikawa, Noboru; Okano, Tomohiro; Sano, Tsukasa

2015-01-01

The purpose of this study was to compare findings on the relationship between impacted molar roots and the mandibular canal in panoramic and three-dimensional cone-beam CT (CBCT) images to identify those that indicated risk of postoperative paresthesia. The relationship between impacted molars and the mandibular canal was first classified using panoramic images. Only patients in whom the molar roots were either in contact with or superimposed on the canal were evaluated using CBCT. Of 466 patients examined using both panoramic and CBCT images, 280 underwent surgical extraction of an impacted molar, and 15 of these (5%) reported postoperative paresthesia. The spatial relationship between the impacted third molar root and the mandibular canal was determined by examining para-sagittal sections (lingual, buccal, inter-radicular, inferior, and combinations) obtained from the canal to the molar root and establishing the proximity of the canal to the molar root (in contact with or without loss of the cortical border and separate). The results revealed that darkening of the roots with interruption of the mandibular canal on panoramic radiographs and the inter-radicular position of the canal in CBCT images were characteristic findings indicative of risk of postoperative paresthesia. These results suggest that careful surgical intervention is required in patients with the above characteristics.

Invesigation of prevalence of dental anomalies by using digital panoramic radiographs.

PubMed

Bilge, Nebiha Hilal; Yeşiltepe, Selin; Törenek Ağırman, Kübra; Çağlayan, Fatma; Bilge, Osman Murat

2017-09-21

This study was performed to evaluate the prevalence of all types and subtypes of dental anomalies among 6 to 40 year-old patients by using panoramic radiographs. This cross-sectional study was conducted by analyzing digital panoramic radiographs of 1200 patients admitted to our clinic in 2014. Dental anomalies were examined under 5 types and 16 subtypes. Dental anomalies were divided into five types: (a) number (including hypodontia, oligodontia and hyperdontia); (b) size (including microdontia and macrodontia); (c) structure (including amelogenesis imperfecta, dentinogenesis imperfecta and dentin dysplasia); (d) position (including transposition, ectopia, displacement, impaction and inversion); (e) shape (including fusion-gemination, dilaceration and taurodontism); RESULTS: The prevalence of dental anomalies diagnosed by panoramic radiographs was 39.2% (men (46%), women (54%)). Anomalies of position (60.8%) and shape (27.8%) were the most common types of abnormalities and anomalies of size (8.2%), structure (0.2%) and number (17%) were the least in both genders. Anomalies of impaction (45.5%), dilacerations (16.3%), hypodontia (13.8%) and taurodontism (11.2%) were the most common subtypes of dental anomalies. Taurodontism was more common in the age groups of 13-19 years. The age range of the most frequent of all other anomalies was 20-29. Anomalies of tooth position were the most common type of dental anomalies and structure anomalies were the least in this Turkish dental population. The frequency and type of dental anomalies vary within and between populations, confirming the role of racial factors in the prevalence of dental anomalies. Digital panoramic radiography is a very useful method for the detection of dental anomalies.

Age estimation by canines' pulp/tooth ratio in an Iranian population using digital panoramic radiography.

PubMed

Dehghani, Mahdieh; Shadkam, Elaheh; Ahrari, Farzaneh; Dehghani, Mahboobe

2018-04-01

Age estimation in adults is an important issue in forensic science. This study aimed to estimate the chronological age of Iranians by means of pulp/tooth area ratio (AR) of canines in digital panoramic radiographs. The sample consisted of panoramic radiographs of 271 male and female subjects aged 16-64 years. The pulp/tooth area ratio (AR) of upper and lower canines was calculated by AutoCAD software. Data were subjected to correlation and regression analysis. There was a significant and inverse correlation between age and pulp/tooth area ratio of upper and lower canines (r=-0.794 for upper canine and r=-0.282 for lower canine; p-value<0.001). Linear regression equations were derived separately for upper, lower and both canines. The mean difference between actual and estimated age using upper canine was 6.07±1.7. The results showed that the pulp/tooth area ratios of canines are a reliable method for age estimation in Iranians. The pulp/tooth area ratio of upper canine was better correlated with chronological age than that of lower canine. Copyright © 2018 Elsevier B.V. All rights reserved.

Panoramic Dental X-Ray

MedlinePlus

... Physician Resources Professions Site Index A-Z Panoramic Dental X-ray Panoramic dental x-ray uses a very small dose of ... x-ray , is a two-dimensional (2-D) dental x-ray examination that captures the entire mouth ...

Performance analysis of panoramic infrared systems

NASA Astrophysics Data System (ADS)

Furxhi, Orges; Driggers, Ronald G.; Holst, Gerald; Krapels, Keith

2014-05-01

Panoramic imagers are becoming more commonplace in the visible part of the spectrum. These imagers are often used in the real estate market, extreme sports, teleconferencing, and security applications. Infrared panoramic imagers, on the other hand, are not as common and only a few have been demonstrated. A panoramic image can be formed in several ways, using pan and stitch, distributed aperture, or omnidirectional optics. When omnidirectional optics are used, the detected image is a warped view of the world that is mapped on the focal plane array in a donut shape. The final image on the display is the mapping of the omnidirectional donut shape image back to the panoramic world view. In this paper we analyze the performance of uncooled thermal panoramic imagers that use omnidirectional optics, focusing on range performance.

Fragile X syndrome: panoramic radiographic evaluation of dental anomalies, dental mineralization stage, and mandibular angle.

PubMed

Sabbagh-Haddad, Aida; Haddad, Denise Sabbagh; Michel-Crosato, Edgard; Arita, Emiko Saito

2016-01-01

The purpose of this study was to evaluate the dental radiographic characteristics as described in 40 records of patients with panoramic radiography. The patients were in the range of 6-17 years old, and were divided into two groups (20 subjects who were compatible with the normality standard and 20 individuals diagnosed with the FXS), which were matched for gender and age. Analysis of the panoramic radiographic examination involved the evaluation of dental mineralization stage, mandibular angle size, and presence of dental anomalies in both deciduous and permanent dentitions. The results of radiographic evaluation demonstrated that the chronology of tooth eruption of all third and second lower molars is anticipated in individuals with FXS (p<0.05). In this group, supernumerary deciduous teeth (2.83%), giroversion of permanent teeth (2.31%), and partial anodontia (1.82%) were the most frequent dental anomalies. In addition, an increase was observed in the mandibular angle size in the FXS group (p<0.05). We conclude that knowledge of dental radiographic changes is of great importance for dental surgeons to plan the treatment of these individuals.

Removing Distortion of Periapical Radiographs in Dental Digital Radiography Using Embedded Markers in an External frame.

PubMed

Kafieh, Rahele; Shahamoradi, Mahdi; Hekmatian, Ehsan; Foroohandeh, Mehrdad; Emamidoost, Mostafa

2012-10-01

To carry out in vivo and in vitro comparative pilot study to evaluate the preciseness of a newly proposed digital dental radiography setup. This setup was based on markers placed on an external frame to eliminate the measurement errors due to incorrect geometry in relative positioning of cone, teeth and the sensor. Five patients with previous panoramic images were selected to undergo the proposed periapical digital imaging for in vivo phase. For in vitro phase, 40 extracted teeth were replanted in dry mandibular sockets and periapical digital images were prepared. The standard reference for real scales of the teeth were obtained through extracted teeth measurements for in vitro application and were calculated through panoramic imaging for in vivo phases. The proposed image processing thechnique was applied on periapical digital images to distinguish the incorrect geometry. The recognized error was inversely applied on the image and the modified images were compared to the correct values. The measurement findings after the distortion removal were compared to our gold standards (results of panoramic imaging or measurements from extracted teeth) and showed the accuracy of 96.45% through in vivo examinations and 96.0% through in vitro tests. The proposed distortion removal method is perfectly able to identify the possible inaccurate geometry during image acquisition and is capable of applying the inverse transform to the distorted radiograph to obtain the correctly modified image. This can be really helpful in applications like root canal therapy, implant surgical procedures and digital subtraction radiography, which are essentially dependent on precise measurements.

Removing Distortion of Periapical Radiographs in Dental Digital Radiography Using Embedded Markers in an External frame

PubMed Central

Kafieh, Rahele; Shahamoradi, Mahdi; Hekmatian, Ehsan; Foroohandeh, Mehrdad; Emamidoost, Mostafa

2012-01-01

To carry out in vivo and in vitro comparative pilot study to evaluate the preciseness of a newly proposed digital dental radiography setup. This setup was based on markers placed on an external frame to eliminate the measurement errors due to incorrect geometry in relative positioning of cone, teeth and the sensor. Five patients with previous panoramic images were selected to undergo the proposed periapical digital imaging for in vivo phase. For in vitro phase, 40 extracted teeth were replanted in dry mandibular sockets and periapical digital images were prepared. The standard reference for real scales of the teeth were obtained through extracted teeth measurements for in vitro application and were calculated through panoramic imaging for in vivo phases. The proposed image processing thechnique was applied on periapical digital images to distinguish the incorrect geometry. The recognized error was inversely applied on the image and the modified images were compared to the correct values. The measurement findings after the distortion removal were compared to our gold standards (results of panoramic imaging or measurements from extracted teeth) and showed the accuracy of 96.45% through in vivo examinations and 96.0% through in vitro tests. The proposed distortion removal method is perfectly able to identify the possible inaccurate geometry during image acquisition and is capable of applying the inverse transform to the distorted radiograph to obtain the correctly modified image. This can be really helpful in applications like root canal therapy, implant surgical procedures and digital subtraction radiography, which are essentially dependent on precise measurements. PMID:23724372

Dental panoramic image analysis for enhancement biomarker of mandibular condyle for osteoporosis early detection

NASA Astrophysics Data System (ADS)

Suprijanto; Azhari; Juliastuti, E.; Septyvergy, A.; Setyagar, N. P. P.

2016-03-01

Osteoporosis is a degenerative disease characterized by low Bone Mineral Density (BMD). Currently, a BMD level is determined by Dual Energy X-ray Absorptiometry (DXA) at the lumbar vertebrae and femur. Previous studies reported that dental panoramic radiography image has potential information for early osteoporosis detection. This work reported alternative scheme, that consists of the determination of the Region of Interest (ROI) the condyle mandibular in the image as biomarker and feature extraction from ROI and classification of bone conditions. The minimum value of intensity in the cavity area is used to compensate an offset on the ROI. For feature extraction, the fraction of intensity values in the ROI that represent high bone density and the ROI total area is perfomed. The classification will be evaluated from the ability of each feature and its combinations for the BMD detection in 2 classes (normal and abnormal), with the artificial neural network method. The evaluation system used 105 panoramic image data from menopause women which consist of 36 training data and 69 test data that were divided into 2 classes. The 2 classes of classification obtained 88.0% accuracy rate and 88.0% sensitivity rate.

The Reliability of Panoramic Radiography Versus Cone Beam Computed Tomography when Evaluating the Distance to the Alveolar Nerve in the Site of Lateral Teeth.

PubMed

Česaitienė, Gabrielė; Česaitis, Kęstutis; Junevičius, Jonas; Venskutonis, Tadas

2017-07-04

BACKGROUND The aim of this study was to compare the reliability of panoramic radiography (PR) and cone beam computed tomography (CBCT) in the evaluation of the distance of the roots of lateral teeth to the inferior alveolar nerve canal (IANC). MATERIAL AND METHODS 100 PR and 100 CBCT images that met the selection criteria were selected from the database. In PR images, the distances were measured using an electronic caliper with 0.01 mm accuracy and white light x-ray film reviewer. Actual values of the measurements were calculated taking into consideration the magnification used in PR images (130%). Measurements on CBCT images were performed using i-CAT Vision software. Statistical data analysis was performed using R software and applying Welch's t-test and the Wilcoxon test. RESULTS There was no statistically significant difference in the mean distance from the root of the second premolar and the mesial and distal roots of the first molar to the IANC between PR and CBCT images. The difference in the mean distance from the mesial and distal roots of the second and the third molars to the IANC measured in PR and CBCT images was statistically significant. CONCLUSIONS PR may be uninformative or misleading when measuring the distance from the mesial and distal roots of the second and the third molars to the IANC.

The Reliability of Panoramic Radiography Versus Cone Beam Computed Tomography when Evaluating the Distance to the Alveolar Nerve in the Site of Lateral Teeth

PubMed Central

Česaitienė, Gabrielė; Česaitis, Kęstutis; Junevičius, Jonas; Venskutonis, Tadas

2017-01-01

Background The aim of this study was to compare the reliability of panoramic radiography (PR) and cone beam computed tomography (CBCT) in the evaluation of the distance of the roots of lateral teeth to the inferior alveolar nerve canal (IANC). Material/Methods 100 PR and 100 CBCT images that met the selection criteria were selected from the database. In PR images, the distances were measured using an electronic caliper with 0.01 mm accuracy and white light x-ray film reviewer. Actual values of the measurements were calculated taking into consideration the magnification used in PR images (130%). Measurements on CBCT images were performed using i-CAT Vision software. Statistical data analysis was performed using R software and applying Welch’s t-test and the Wilcoxon test. Results There was no statistically significant difference in the mean distance from the root of the second premolar and the mesial and distal roots of the first molar to the IANC between PR and CBCT images. The difference in the mean distance from the mesial and distal roots of the second and the third molars to the IANC measured in PR and CBCT images was statistically significant. Conclusions PR may be uninformative or misleading when measuring the distance from the mesial and distal roots of the second and the third molars to the IANC. PMID:28674379

Changes in jawbones of male patients with chronic renal failure on digital panoramic radiographs.

PubMed

Dagistan, Saadettin; Miloglu, Ozkan; Caglayan, Fatma

2016-01-01

To compare the existence of gonial cortical bone thickness, antegonial index, mandibular canal bone resorption and gonial angle values and pathologies like ground-glass appearance in jawbones and brown tumor in male patients undergoing dialysis due to chronic renal failure and men from the healthy control group on panoramic radiographs. Panoramic radiographs were taken from 80 male individuals in total (40 normal and 40 dialysis patients). Values obtained from the right and left sides of the mandible were summed and their means were calculated. Gonial cortical thickness, antegonial index and gonial angle values were assessed with the Student's t-test, mandibular canal wall resorption with the Chi-square test, and pathologies such as ground-glass appearance and Brown tumor as "available" or "not available." Statistically significant differences were observed among the antegonial index (P < 0.001), gonial cortical bone thickness (P < 0.001), and gonial angle (P < 0.001) values of study and control groups. Besides, mandibular canal wall resorption (P < 0.001) was also statistically significant. In the study group, pathologies with ground-glass appearance were encountered in mandible, but no radiographic findings were observed similar to brown tumor. Compared to the control group, decreases were found in gonial cortical bone thicknesses, antegonial index values, mandibular canal wall resorption, and gonial angle values of the patients receiving dialysis treatment due to chronic renal failure. Although it is not statistically significant, pathology with ground-glass appearance was detected in a patient, but no pathologies like brown tumor were observed. These findings from patients with chronic renal failure must be evaluated in panoramic radiography.

Dichotomy between theory and practice in chest radiography and its impact on students.

PubMed

Botwe, Benard O; Arthur, Lawrence; Tenkorang, Michael K K; Anim-Sampong, Samuel

2017-06-01

It is important that theory is synchronous with clinical practices that students engage in. Lack of congruence between theory and practice presents serious problems to students. This study was therefore conducted to determine if there was a theory-practice gap in chest radiography during clinical rotations, and any associated causes and effects on radiography students. A descriptive survey design was used to conduct this study from 2 February to 27 July 2014. A semi-structured questionnaire consisting of open- and close-ended questions was used to purposively collect data from 26 radiography students in Ghana who had completed theory lessons in chest radiography and had either completed or were undertaking clinical rotations in chest radiography. Twenty-five (96%) respondents indicated the presence of theory-practice gap in chest radiography during clinical rotations, where differences between theory and clinical practice were observed. Lack of working materials 16 (62%), heavy workload 14 (54%), equipment breakdowns 14 (54%) and supervisory factors 11 (43%) were identified as the causes. Many students (81%) experienced diverse adverse effects such as confusion 10 (38%), poor performance during clinical examinations 6 (23%) and entire loss of interest in the professional training 1 (4%) of this dichotomy. Dichotomy between theory and practice found in chest radiography has diverse adverse effects on students. Regular feedback on the quality of clinical practice received by students should be encouraged to determine the existence of any gaps between theory and practice in order to promote effective clinical rotation programmes in radiography. © 2016 The Authors. Journal of Medical Radiation Sciences published by John Wiley & Sons Australia, Ltd on behalf of Australian Society of Medical Imaging and Radiation Therapy and New Zealand Institute of Medical Radiation Technology.

The effect of dose reduction on the detection of anatomical structures on panoramic radiographs.

PubMed

Kaeppler, G; Dietz, K; Reinert, S

2006-07-01

The aim was to evaluate the effect of dose reduction on diagnostic accuracy using different screen-film combinations and digital techniques for panoramic radiography. Five observers assessed 201 pairs of panoramic radiographs (a total of 402 panoramic radiographs) taken with the Orthophos Plus (Sirona, Bensheim, Germany), for visualization of 11 anatomical structures on each side, using a 3-point scale -1, 0 and 1. Two radiographs of each patient were taken at two different times (conventional setting and setting with decreased dose, done by increasing tube potential settings or halving tube current). To compare the dose at different tube potential settings dose-length product was measured at the secondary collimator. Films with medium and regular intensifying screens (high and low tube potential settings) and storage phosphor plates (low tube potential setting, tube current setting equivalent to regular intensifying screen and halved) were compared. The five observers made 27 610 assessments. Intrarater agreement was expressed by Cohen's kappa coefficient. The results demonstrated an equivalence of regular screens (low tube potential setting) and medium screens (high and low tube potential settings). A significant difference existed between medium screens (low tube potential setting, mean score 0.92) and the group of regular film-screen combinations at high tube potential settings (mean score 0.89) and between all film-screen combinations and the digital system irrespective of exposure (mean score below 0.82). There were no significant differences between medium and regular screens (mean score 0.88 to 0.92) for assessment of the periodontal ligament space, but there was a significant difference compared with the digital system (mean score below 0.76). The kappa coefficient for intrarater agreement was moderate (0.55). New regular intensifying screens can replace medium screens at low tube potential settings. Digital panoramic radiographs should be taken at low

Correlation of panoramic radiography and cone beam CT findings in the assessment of the relationship between impacted mandibular third molars and the mandibular canal

PubMed Central

Neves, F S; Souza, T C; Almeida, S M; Haiter-Neto, F; Freitas, D Q; Bóscolo, F N

2012-01-01

Objectives The aim of this study was to assess the reliability of four panoramic radiographic findings, both individually and in association, in predicting the absence of corticalization between the mandibular canal and the third molar on cone beam CT (CBCT) images. Methods The sample consisted of 72 individuals (142 mandibular third molars) who underwent pre-operative radiographic evaluation before extraction of impacted mandibular third molars. On panoramic radiographs, the most common signs of corticalization (darkening of roots, diversion of mandibular canal, narrowing of mandibular canal and interruption of white line) and the presence or absence of corticalization between the mandibular third molar and the mandibular canal on CBCT images were evaluated. Results Darkening of roots and interruption of white line associated with the absence of corticalization between the mandibular third molar and the mandibular canal on CBCT images were statistically significant, both as isolated findings (p = 0.0001 and p = 0.0006, respectively) and in association (p = 0.002). No statistically significant association was observed for the other panoramic radiographic findings, either individually or in association (p > 0.05). Conclusion Darkening of roots and interruption of white line observed on panoramic radiographs, both as isolated findings and in association, were effective in determining the risk relationship between the tooth roots and the mandibular canal, requiring three-dimensional evaluation of the case. PMID:22282507

Panoramic stereo sphere vision

NASA Astrophysics Data System (ADS)

Feng, Weijia; Zhang, Baofeng; Röning, Juha; Zong, Xiaoning; Yi, Tian

2013-01-01

Conventional stereo vision systems have a small field of view (FOV) which limits their usefulness for certain applications. While panorama vision is able to "see" in all directions of the observation space, scene depth information is missed because of the mapping from 3D reference coordinates to 2D panoramic image. In this paper, we present an innovative vision system which builds by a special combined fish-eye lenses module, and is capable of producing 3D coordinate information from the whole global observation space and acquiring no blind area 360°×360° panoramic image simultaneously just using single vision equipment with one time static shooting. It is called Panoramic Stereo Sphere Vision (PSSV). We proposed the geometric model, mathematic model and parameters calibration method in this paper. Specifically, video surveillance, robotic autonomous navigation, virtual reality, driving assistance, multiple maneuvering target tracking, automatic mapping of environments and attitude estimation are some of the applications which will benefit from PSSV.

Panoramic projection avionics displays

NASA Astrophysics Data System (ADS)

Kalmanash, Michael H.

2003-09-01

Avionics projection displays are entering production in advanced tactical aircraft. Early adopters of this technology in the avionics community used projection displays to replace or upgrade earlier units incorporating direct-view CRT or AMLCD devices. Typical motivation for these upgrades were the alleviation of performance, cost and display device availability concerns. In these systems, the upgraded (projection) displays were one-for-one form / fit replacements for the earlier units. As projection technology has matured, this situation has begun to evolve. The Lockheed-Martin F-35 is the first program in which the cockpit has been specifically designed to take advantage of one of the more unique capabilities of rear projection display technology, namely the ability to replace multiple small screens with a single large conformal viewing surface in the form of a panoramic display. Other programs are expected to follow, since the panoramic formats enable increased mission effectiveness, reduced cost and greater information transfer to the pilot. Some of the advantages and technical challenges associated with panoramic projection displays for avionics applications are described below.

Automatic panoramic thermal integrated sensor

NASA Astrophysics Data System (ADS)

Gutin, Mikhail A.; Tsui, Eddy K.; Gutin, Olga N.

2005-05-01

Historically, the US Army has recognized the advantages of panoramic imagers with high image resolution: increased area coverage with fewer cameras, instantaneous full horizon detection, location and tracking of multiple targets simultaneously, extended range, and others. The novel ViperViewTM high-resolution panoramic thermal imager is the heart of the Automatic Panoramic Thermal Integrated Sensor (APTIS), being jointly developed by Applied Science Innovative, Inc. (ASI) and the Armament Research, Development and Engineering Center (ARDEC) in support of the Future Combat Systems (FCS) and the Intelligent Munitions Systems (IMS). The APTIS is anticipated to operate as an intelligent node in a wireless network of multifunctional nodes that work together to improve situational awareness (SA) in many defense and offensive operations, as well as serve as a sensor node in tactical Intelligence Surveillance Reconnaissance (ISR). The ViperView is as an aberration-corrected omnidirectional imager with small optics designed to match the resolution of a 640x480 pixels IR camera with improved image quality for longer range target detection, classification, and tracking. The same approach is applicable to panoramic cameras working in the visible spectral range. Other components of the ATPIS sensor suite include ancillary sensors, advanced power management, and wakeup capability. This paper describes the development status of the APTIS system.

Thermal infrared panoramic imaging sensor

NASA Astrophysics Data System (ADS)

Gutin, Mikhail; Tsui, Eddy K.; Gutin, Olga; Wang, Xu-Ming; Gutin, Alexey

2006-05-01

Panoramic cameras offer true real-time, 360-degree coverage of the surrounding area, valuable for a variety of defense and security applications, including force protection, asset protection, asset control, security including port security, perimeter security, video surveillance, border control, airport security, coastguard operations, search and rescue, intrusion detection, and many others. Automatic detection, location, and tracking of targets outside protected area ensures maximum protection and at the same time reduces the workload on personnel, increases reliability and confidence of target detection, and enables both man-in-the-loop and fully automated system operation. Thermal imaging provides the benefits of all-weather, 24-hour day/night operation with no downtime. In addition, thermal signatures of different target types facilitate better classification, beyond the limits set by camera's spatial resolution. The useful range of catadioptric panoramic cameras is affected by their limited resolution. In many existing systems the resolution is optics-limited. Reflectors customarily used in catadioptric imagers introduce aberrations that may become significant at large camera apertures, such as required in low-light and thermal imaging. Advantages of panoramic imagers with high image resolution include increased area coverage with fewer cameras, instantaneous full horizon detection, location and tracking of multiple targets simultaneously, extended range, and others. The Automatic Panoramic Thermal Integrated Sensor (APTIS), being jointly developed by Applied Science Innovative, Inc. (ASI) and the Armament Research, Development and Engineering Center (ARDEC) combines the strengths of improved, high-resolution panoramic optics with thermal imaging in the 8 - 14 micron spectral range, leveraged by intelligent video processing for automated detection, location, and tracking of moving targets. The work in progress supports the Future Combat Systems (FCS) and the

Panoramic lens designed with transformation optics.

PubMed

Wang, Huaping; Deng, Yangyang; Zheng, Bin; Li, Rujiang; Jiang, Yuyu; Dehdashti, Shahram; Xu, Zhiwei; Chen, Hongsheng

2017-01-06

The panoramic lens is a special kind of lens, which is applied to observe full view. In this letter, we theoretically present a panoramic lens (PL) using transformation optics method. The lens is designed with inhomogeneous and anisotropic constitutive parameters, which has the ability to gather light from all directions and confine light within the visual angle of observer. Simulation results validate our theoretical design.

Panoramic Images Mapping Tools Integrated Within the ESRI ArcGIS Software

NASA Astrophysics Data System (ADS)

Guo, Jiao; Zhong, Ruofei; Zeng, Fanyang

2014-03-01

There is a general study on panoramic images which are presented along with appearance of the Google street map. Despite 360 degree viewing of street, we can realize more applications over panoramic images. This paper developed a toolkits plugged in ArcGIS, which can view panoramic photographs at street level directly from ArcMap and measure and capture all visible elements as frontages, trees and bridges. We use a series of panoramic images adjoined with absolute coordinate through GPS and IMU. There are two methods in this paper to measure object from these panoramic images: one is to intersect object position through a stereogram; the other one is multichip matching involved more than three images which all cover the object. While someone wants to measure objects from these panoramic images, each two panoramic images which both contain the object can be chosen to display on ArcMap. Then we calculate correlation coefficient of the two chosen panoramic images so as to calculate the coordinate of object. Our study test different patterns of panoramic pairs and compare the results of measurement to the real value of objects so as to offer the best choosing suggestion. The article has mainly elaborated the principles of calculating correlation coefficient and multichip matching.

Assessment of Root Resorption and Root Shape by Periapical and Panoramic Radiographs: A Comparative Study.

PubMed

Ahuja, Puneeta D; Mhaske, Sheetal P; Mishra, Gaurav; Bhardwaj, Atul; Dwivedi, Ruby; Mangalekar, Sachin B

2017-06-01

One of the common findings encountered by the clinician at the end of orthodontic treatment is the apical root resorption. Root resorption occurs to various degrees. A severe form of root resorption is characterized by shortening of root for more than 4 mm or more than one-third of the total tooth length. A low incidence rate of resorption is observed based on radiographic findings for the diagnosis of root resorption, panoramic radiography, and periapical radiography. Hence, we evaluated the accuracy of panoramic radiographic films for assessing the root resorption in comparison with the periapical films. This study included the assessment of all the cases in which pre- and post-treatment radiographs were available for analysis of the assessment of the amount of root resorption. Complete records of 80 patients were analyzed. Examination of a total of 900 teeth was done. Mean age of the patients in this study was 21 years ranging from 11 to 38 years. The majority of the patients in the present study were females. All the treatments were carried out by registered experienced orthodontists having minimum experience of more than 10 years. All the cases were divided into two study groups. Group I comprised panoramic radiographic findings, while group II consisted of periapical radiographic findings. For the measurement of crown portion, root portion, and the complete root length, magnification loops of over 100 powers with parallax correction with inbuilt grids were used. Assessment of the tooth length and the crown length was done by the same observers. All the results were analyzed by Statistical Package for the Social Sciences software version 6.0. Maximum amount of root resorption was observed in case of maxillary central incisors and canines among group I and II cases respectively. However, nonsignificant difference was obtained while comparing the mean root resorption in relation to maxillary incisors and canines among the two study groups. While comparing the

Experiments in interactive panoramic cinema

NASA Astrophysics Data System (ADS)

Fisher, Scott S.; Anderson, Steve; Ruiz, Susana; Naimark, Michael; Hoberman, Perry; Bolas, Mark; Weinberg, Richard

2005-03-01

For most of the past 100 years, cinema has been the premier medium for defining and expressing relations to the visible world. However, cinematic spectacles delivered in darkened theaters are predicated on a denial of both the body and the physical surroundings of the spectators who are watching it. To overcome these deficiencies, filmmakers have historically turned to narrative, seducing audiences with compelling stories and providing realistic characters with whom to identify. This paper describes several research projects in interactive panoramic cinema that attempt to sidestep the narrative preoccupations of conventional cinema and instead are based on notions of space, movement and embodied spectatorship rather than traditional storytelling. Example projects include interactive works developed with the use of a unique 360 degree camera and editing system, and also development of panoramic imagery for a large projection environment with 14 screens on 3 adjacent walls in a 5-4-5 configuration with observations and findings from an experiment projecting panoramic video on 12 of the 14, in a 4-4-4 270 degree configuration.

Void fraction and velocity measurement of simulated bubble in a rotating disc using high frame rate neutron radiography.

PubMed

Saito, Y; Mishima, K; Matsubayashi, M

2004-10-01

To evaluate measurement error of local void fraction and velocity field in a gas-molten metal two-phase flow by high-frame-rate neutron radiography, experiments using a rotating stainless-steel disc, which has several holes of various diameters and depths simulating gas bubbles, were performed. Measured instantaneous void fraction and velocity field of the simulated bubbles were compared with the calculated values based on the rotating speed, the diameter and the depth of the holes as parameters and the measurement error was evaluated. The rotating speed was varied from 0 to 350 rpm (tangential velocity of the simulated bubbles from 0 to 1.5 m/s). The effect of shutter speed of the imaging system on the measurement error was also investigated. It was revealed from the Lagrangian time-averaged void fraction profile that the measurement error of the instantaneous void fraction depends mainly on the light-decay characteristics of the fluorescent converter. The measurement error of the instantaneous local void fraction of simulated bubbles is estimated to be 20%. In the present imaging system, the light-decay characteristics of the fluorescent converter affect the measurement remarkably, and so should be taken into account in estimating the measurement error of the local void fraction profile.

Panoramic Scanning: Essential Element of Higher-Order Thought.

ERIC Educational Resources Information Center

Ambrose, Don

1996-01-01

Panoramic scanning is the capacity to perceive, interpret, and appreciate complex problems from a big-picture vantage point. Barriers to panoramic scanning (sensory bombardment, superficial polarized thought, and tunnel vision) and facilitators (broad interests and knowledge, pattern finding, and connection-making skills) are identified. Educators…

Evaluation of the diagnostic yield of dental radiography and cone-beam computed tomography for the identification of anatomic landmarks in small to medium-sized brachycephalic dogs.

PubMed

Döring, Sophie; Arzi, Boaz; Barich, Catherine R; Hatcher, David C; Kass, Philip H; Verstraete, Frank J M

2018-01-01

OBJECTIVE To evaluate the diagnostic yield of dental radiography (Rad method) and 3 cone-beam CT (CBCT) methods for the identification of predefined anatomic landmarks in brachycephalic dogs. ANIMALS 19 client-owned brachycephalic dogs admitted for evaluation and treatment of dental disease. PROCEDURES 26 predefined anatomic landmarks were evaluated separately by use of the RAD method and 3 CBCT software modules (serial CBCT slices and custom cross sections, tridimensional rendering, and reconstructed panoramic views). A semiquantitative scoring system was used, and mean scores were calculated for each anatomic landmark and imaging method. The Friedman test was used to evaluate values for significant differences in diagnostic yield. For values that were significant, the Wilcoxon signed rank test was used with the Bonferroni-Holm multiple comparison adjustment to determine significant differences among each of the 6 possible pairs of diagnostic methods. RESULTS Differences of diagnostic yield among the Rad and 3 CBCT methods were significant for 19 of 26 anatomic landmarks. For these landmarks, Rad scores were significantly higher than scores for reconstructed panoramic views for 4 of 19 anatomic landmarks, but Rad scores were significantly lower than scores for reconstructed panoramic views for 8 anatomic landmarks, tridimensional rendering for 18 anatomic landmarks, and serial CBCT slices and custom cross sections for all 19 anatomic landmarks. CONCLUSIONS AND CLINICAL RELEVANCE CBCT methods were better suited than dental radiography for the identification of anatomic landmarks in brachycephalic dogs. Results of this study can serve as a basis for CBCT evaluation of dental disorders in brachycephalic dogs.

Method and Apparatus for Computed Imaging Backscatter Radiography

NASA Technical Reports Server (NTRS)

Shedlock, Daniel (Inventor); Sabri, Nissia (Inventor); Dugan, Edward T. (Inventor); Jacobs, Alan M. (Inventor); Meng, Christopher (Inventor)

2013-01-01

Systems and methods of x-ray backscatter radiography are provided. A single-sided, non-destructive imaging technique utilizing x-ray radiation to image subsurface features is disclosed, capable of scanning a region using a fan beam aperture and gathering data using rotational motion.

Can dental pulp calcification predict the risk of ischemic cardiovascular disease?

PubMed

Khojastepour, Leila; Bronoosh, Pegah; Khosropanah, Shahdad; Rahimi, Elham

2013-09-01

To report the association of pulp calcification with that of cardiovascular disease (CVD) using digital panoramic dental radiographs. Digital panoramic radiographs of patients referred from the angiography department were included if the patient was under 55 years old and had non-restored or minimally restored molars and canines. An oral and maxillofacial radiologist evaluated the images for pulpal calcifications in the selected teeth. The sensitivity, specificity, positive predictive value and negative predictive value of panoramic radiography in predicting CVD were calculated. Out of 122 patients who met the criteria, 68.2% of the patients with CVD had pulp chamber calcifications. Pulp calcification in panoramic radiography had a sensitivity of 68.9% to predict CVD. This study demonstrates that patients with CVD show an increased incidence of pulp calcification compared with healthy patients. The findings suggest that pulp calcification on panoramic radiography may have possibilities for use in CVD screening.

Quantifying navigational information: The catchment volumes of panoramic snapshots in outdoor scenes.

PubMed

Murray, Trevor; Zeil, Jochen

2017-01-01

Panoramic views of natural environments provide visually navigating animals with two kinds of information: they define locations because image differences increase smoothly with distance from a reference location and they provide compass information, because image differences increase smoothly with rotation away from a reference orientation. The range over which a given reference image can provide navigational guidance (its 'catchment area') has to date been quantified from the perspective of walking animals by determining how image differences develop across the ground plane of natural habitats. However, to understand the information available to flying animals there is a need to characterize the 'catchment volumes' within which panoramic snapshots can provide navigational guidance. We used recently developed camera-based methods for constructing 3D models of natural environments and rendered panoramic views at defined locations within these models with the aim of mapping navigational information in three dimensions. We find that in relatively open woodland habitats, catchment volumes are surprisingly large extending for metres depending on the sensitivity of the viewer to image differences. The size and the shape of catchment volumes depend on the distance of visual features in the environment. Catchment volumes are smaller for reference images close to the ground and become larger for reference images at some distance from the ground and in more open environments. Interestingly, catchment volumes become smaller when only above horizon views are used and also when views include a 1 km distant panorama. We discuss the current limitations of mapping navigational information in natural environments and the relevance of our findings for our understanding of visual navigation in animals and autonomous robots.

Quantifying navigational information: The catchment volumes of panoramic snapshots in outdoor scenes

PubMed Central

Zeil, Jochen

2017-01-01

Panoramic views of natural environments provide visually navigating animals with two kinds of information: they define locations because image differences increase smoothly with distance from a reference location and they provide compass information, because image differences increase smoothly with rotation away from a reference orientation. The range over which a given reference image can provide navigational guidance (its ‘catchment area’) has to date been quantified from the perspective of walking animals by determining how image differences develop across the ground plane of natural habitats. However, to understand the information available to flying animals there is a need to characterize the ‘catchment volumes’ within which panoramic snapshots can provide navigational guidance. We used recently developed camera-based methods for constructing 3D models of natural environments and rendered panoramic views at defined locations within these models with the aim of mapping navigational information in three dimensions. We find that in relatively open woodland habitats, catchment volumes are surprisingly large extending for metres depending on the sensitivity of the viewer to image differences. The size and the shape of catchment volumes depend on the distance of visual features in the environment. Catchment volumes are smaller for reference images close to the ground and become larger for reference images at some distance from the ground and in more open environments. Interestingly, catchment volumes become smaller when only above horizon views are used and also when views include a 1 km distant panorama. We discuss the current limitations of mapping navigational information in natural environments and the relevance of our findings for our understanding of visual navigation in animals and autonomous robots. PMID:29088300

Panoramic Epipolar Image Generation for Mobile Mapping System

NASA Astrophysics Data System (ADS)

Chen, T.; Yamamoto, K.; Chhatkuli, S.; Shimamura, H.

2012-07-01

The notable improvements on performance and low cost of digital cameras and GPS/IMU devices have caused MMSs (Mobile Mapping Systems) to be gradually becoming one of the most important devices for mapping highway and railway networks, generating and updating road navigation data and constructing urban 3D models over the last 20 years. Moreover, the demands for large scale visual street-level image database construction by the internet giants such as Google and Microsoft have made the further rapid development of this technology. As one of the most important sensors, the omni-directional cameras are being commonly utilized on many MMSs to collect panoramic images for 3D close range photogrammetry and fusion with 3D laser point clouds since these cameras could record much visual information of the real environment in one image at field view angle of 360° in longitude direction and 180° in latitude direction. This paper addresses the problem of panoramic epipolar image generation for 3D modelling and mapping by stereoscopic viewing. These panoramic images are captured with Point Grey's Ladybug3 mounted on the top of Mitsubishi MMS-X 220 at 2m intervals along the streets in urban environment. Onboard GPS/IMU, speedometer and post sequence image analysis technology such as bundle adjustment provided high accuracy position and attitude data for these panoramic images and laser data, this makes it possible to construct the epipolar geometric relationship between any two adjacent panoramic images and then the panoramic epipolar images could be generated. Three kinds of projection planes: sphere, cylinder and flat plane are selected as the epipolar images' planes. In final we select the flat plane and use its effective parts (middle parts of base line's two sides) for epipolar image generation. The corresponding geometric relations and results will be presented in this paper.

Evaluation of third molar development and its relation to chronological age: a panoramic radiographic study.

PubMed

Zandi, Mohammad; Shokri, Abbas; Malekzadeh, Hamid; Amini, Payam; Shafiey, Parastu

2015-06-01

Third molar development, in comparison to other teeth in the dentition, has the greatest variation in morphology, anatomical position, and time of development and eruption, and its reliability for chronological age estimation is controversial. The aim of the present study was to evaluate third molar development and its relation to chronological age using panoramic radiography. A total of 2536 digital panoramic radiographs of individuals aged between 5 and 26 years were selected. The developmental status of the third molars was assessed using eight-stage developmental scoring proposed by Demirjian et al., with one modification: a stage 0 was added. The collected data were entered into a checklist and subjected to statistical analyses. The mean ages of the first appearance of third molar bud, complete crown formation, and root apex closure were around 9, 14, and 22 years, respectively. In both jaws, third molar development occurred symmetrically, and sexual dimorphism was observed at some developmental stages. Finally, two formulas were presented to estimate age of the juveniles and adolescents based on their gender and developmental stages of the third molars, and validated on a second sample consisting of 523 individuals aged between 8 and 22. Assessment of third molar development was found to be a reliable method for age estimation of individuals between 11 and 22 years. Because of possible ethnic and geographic differences in third molar development, population specific researches were recommended.

Designing 3 Dimensional Virtual Reality Using Panoramic Image

NASA Astrophysics Data System (ADS)

Wan Abd Arif, Wan Norazlinawati; Wan Ahmad, Wan Fatimah; Nordin, Shahrina Md.; Abdullah, Azrai; Sivapalan, Subarna

The high demand to improve the quality of the presentation in the knowledge sharing field is to compete with rapidly growing technology. The needs for development of technology based learning and training lead to an idea to develop an Oil and Gas Plant Virtual Environment (OGPVE) for the benefit of our future. Panoramic Virtual Reality learning based environment is essential in order to help educators overcome the limitations in traditional technical writing lesson. Virtual reality will help users to understand better by providing the simulations of real-world and hard to reach environment with high degree of realistic experience and interactivity. Thus, in order to create a courseware which will achieve the objective, accurate images of intended scenarios must be acquired. The panorama shows the OGPVE and helps to generate ideas to users on what they have learnt. This paper discusses part of the development in panoramic virtual reality. The important phases for developing successful panoramic image are image acquisition and image stitching or mosaicing. In this paper, the combination of wide field-of-view (FOV) and close up image used in this panoramic development are also discussed.

Endoscopic measurements using a panoramic annular lens

NASA Technical Reports Server (NTRS)

Gilbert, John A.; Matthys, Donald R.

1992-01-01

The objective of this project was to design, build, demonstrate, and deliver a prototype system for making measurements within cavities. The system was to utilize structured lighting as the means for making measurements and was to rely on a stationary probe, equipped with a unique panoramic annular lens, to capture a cylindrical view of the illuminated cavity. Panoramic images, acquired with a digitizing camera and stored in a desk top computer, were to be linearized and analyzed by mouse-driven interactive software.

Prevalence of dental anomalies among 7- to 35-year-old people in Hamadan, Iran in 2012-2013 as observed using panoramic radiographs.

PubMed

Shokri, Abbas; Poorolajal, Jalal; Khajeh, Samira; Faramarzi, Farhad; Kahnamoui, Hanieh Mogaver

2014-03-01

This study was performed to evaluate the prevalence of all types and subtypes of dental anomalies among 7- to 35-year-old patients by using panoramic radiographs. This cross-sectional study was conducted on 1649 people in Hamadan City, in 2012-2013. The prevalence of four types and 12 subtypes of dental anomalies was evaluated by two observers separately by using panoramic radiography. Dental anomalies were divided into four types: (a) shape (including fusion, taurodontism, and dens invagination); (b) number (including hypodontia, oligodontia, and hyperdontia); (c) structure (including amelogenesis imperfecta, dentinogenesis imperfecta, and dentin dysplasia); and (d) position (including displacement, impaction, and dilacerations). The reliability between the two observers was 79.56% according to the Kappa statistics. The prevalence of dental anomalies diagnosed by panoramic radiographs was 29%. Anomalies of position and number were the most common types of abnormalities, and anomalies of shape and structure were the least in both genders. Anomalies of impaction (44.76%), dilacerations (21.11%), hypodontia (15.88%), taurodontism (9.29%), and hyperdontia (6.76%) were the most common subtypes of dental anomalies. The anomalies of shape and number were more common in the age groups of 7-12 years and 13-15 years, respectively, while the anomalies of structure and position were more common among the other age groups. Anomalies of tooth position were the most common type of dental anomalies, and structure anomalies were the least in this Iranian population. The frequency and type of dental anomalies vary within and between populations, confirming the role of racial factors in the prevalence of dental anomalies.

Intraoperative panoramic image using alignment grid, is it accurate?

PubMed

Apivatthakakul, T; Duanghakrung, M; Luevitoonvechkit, S; Patumasutra, S

2013-07-01

Minimally invasive orthopedic trauma surgery relies heavily on intraoperative fluoroscopic images to evaluate the quality of fracture reduction and fixation. However, fluoroscopic images have a narrow field of view and often cannot visualize the entire long bone axis. To compare the coronal femoral alignment between conventional X-rays to that achieved with a new method of acquiring a panoramic intraoperative image. Twenty-four cadaveric femurs with simple diaphyseal fractures were fixed with an angulated broad DCP to create coronal plane malalignment. An intraoperative alignment grid was used to help stitch different fluoroscopic images together to produce a panoramic image. A conventional X-ray of the entire femur was then performed. The coronal plane angulation in the panoramic images was then compared to the conventional X-rays using a Wilcoxon signed rank test. The mean angle measured from the panoramic view was 173.9° (range 169.3°-178.0°) with median of 173.2°. The mean angle measured from the conventional X-ray was 173.4° (range 167.7°-178.7°) with a median angle of 173.5°. There was no significant difference between both methods of measurement (P = 0.48). Panoramic images produced by stitching fluoroscopic images together with help of an alignment grid demonstrated the same accuracy at evaluating the coronal plane alignment of femur fractures as conventional X-rays.

Design of a novel panoramic lens without central blindness

NASA Astrophysics Data System (ADS)

Gong, Chen; Cheng, Dewen; Xu, Chen; Wang, Yongtian

2015-08-01

The panoramic lenses are getting more and more popular in recent years. However, these lenses have the drawback of obscuring the rays of the coaxial fields, thus cause blind area in the center field of vision. We present a novel panoramic system consisting of two optical channels to overcome this issue, the system has a field of view (FOV) reaching 200 in vertical and 360 in horizontal direction without blindness area. The two channels have different focal lengths, providing design flexibility to meet application requirements where the center FOV or the marginal FOV is of more interest. The system has no half-reflecting surfaces to ensure high transmission ratio, but this feature greatly increase the design difficulty. The distortion of the novel lens is much smaller than traditional panoramic lenses since the distortion has two node points. Due to the ability of information acquisition in real-time and wide-angle, the novel panoramic lens would be very useful for a variety of real-world applications such as surveillance, short-throw projector and pilotless automobile.

Concave omnidirectional imaging device for cylindrical object based on catadioptric panoramic imaging

NASA Astrophysics Data System (ADS)

Wu, Xiaojun; Wu, Yumei; Wen, Peizhi

2018-03-01

To obtain information on the outer surface of a cylinder object, we propose a catadioptric panoramic imaging system based on the principle of uniform spatial resolution for vertical scenes. First, the influence of the projection-equation coefficients on the spatial resolution and astigmatism of the panoramic system are discussed, respectively. Through parameter optimization, we obtain the appropriate coefficients for the projection equation, and so the imaging quality of the entire imaging system can reach an optimum value. Finally, the system projection equation is calibrated, and an undistorted rectangular panoramic image is obtained using the cylindrical-surface projection expansion method. The proposed 360-deg panoramic-imaging device overcomes the shortcomings of existing surface panoramic-imaging methods, and it has the advantages of low cost, simple structure, high imaging quality, and small distortion, etc. The experimental results show the effectiveness of the proposed method.

Three-dimensional images contribute to the diagnosis of mucous retention cyst in maxillary sinus.

PubMed

Donizeth-Rodrigues, Cleomar; Fonseca-Da Silveira, Márcia; Gonçalves-De Alencar, Ana-Helena; Garcia-Santos-Silva, Maria-Alves; Francisco-De-Mendonça, Elismauro; Estrela, Carlos

2013-01-01

To evaluate the detection of mucous retention cyst of maxillary sinus (MRCMS) using panoramic radiography and cone beam computed tomography (CBCT). A digital database with 6,000 panoramic radiographs was reviewed for MRCMS. Suggestive images of MRCMS were detected on 185 radiographs, and patients were located and invited to return for follow-up. Thirty patients returned, and control panoramic radiographs were obtained 6 to 46 months after the initial radiograph. When MRCMS was found on control radiographs, CBCT scans were obtained. Cysts were measured and compared on radiographs and scans. The Wilcoxon, Spearman and Kolmorogov-Smirnov tests were used for statistical analysis. The level of significance was set at 5%. There were statistically significant differences between the two methods (p<0.05): 23 MRCMS detected on panoramic radiographs were confirmed by CBCT, but 5 MRCMS detected on CBCT images had not been identified by panoramic radiography. Eight MRCMS detected on control radiographs were not confirmed by CBCT. MRCMS size differences from initial to control panoramic radiographs and CBCT scans were not statistically significant (p= 0.617 and p= 0.626). The correlation between time and MRCMS size differences was not significant (r = -0.16, p = 0.381). CBCT scanning detect MRCMS more accurately than panoramic radiography.

Three-dimensional images contribute to the diagnosis of mucous retention cyst in maxillary sinus

PubMed Central

Donizeth-Rodrigues, Cleomar; Fonseca-Da Silveira, Márcia; Gonçalves-De Alencar, Ana H.; Garcia-Santos-Silva, Maria A.; Francisco-De-Mendonça, Elismauro

2013-01-01

Objective: To evaluate the detection of mucous retention cyst of maxillary sinus (MRCMS) using panoramic radiography and cone beam computed tomography (CBCT). Study Design: A digital database with 6,000 panoramic radiographs was reviewed for MRCMS. Suggestive images of MRCMS were detected on 185 radiographs, and patients were located and invited to return for follow-up. Thirty patients returned, and control panoramic radiographs were obtained 6 to 46 months after the initial radiograph. When MRCMS was found on control radiographs, CBCT scans were obtained. Cysts were measured and compared on radiographs and scans. The Wilcoxon, Spearman and Kolmorogov-Smirnov tests were used for statistical analysis. The level of significance was set at 5%. Results: There were statistically significant differences between the two methods (p<0.05): 23 MRCMS detected on panoramic radiographs were confirmed by CBCT, but 5 MRCMS detected on CBCT images had not been identified by panoramic radiography. Eight MRCMS detected on control radiographs were not confirmed by CBCT. MRCMS size differences from initial to control panoramic radiographs and CBCT scans were not statistically significant (p= 0.617 and p= 0.626). The correlation between time and MRCMS size differences was not significant (r = -0.16, p = 0.381). Conclusion: CBCT scanning detect MRCMS more accurately than panoramic radiography. Key words:Mucous cyst, maxillary sinus, panoramic radiograph, cone beam computed tomography. PMID:23229251

An automatic panoramic image reconstruction scheme from dental computed tomography images

PubMed Central

Papakosta, Thekla K; Savva, Antonis D; Economopoulos, Theodore L; Gröhndal, H G

2017-01-01

Objectives: Panoramic images of the jaws are extensively used for dental examinations and/or surgical planning because they provide a general overview of the patient's maxillary and mandibular regions. Panoramic images are two-dimensional projections of three-dimensional (3D) objects. Therefore, it should be possible to reconstruct them from 3D radiographic representations of the jaws, produced by CBCT scanning, obviating the need for additional exposure to X-rays, should there be a need of panoramic views. The aim of this article is to present an automated method for reconstructing panoramic dental images from CBCT data. Methods: The proposed methodology consists of a series of sequential processing stages for detecting a fitting dental arch which is used for projecting the 3D information of the CBCT data to the two-dimensional plane of the panoramic image. The detection is based on a template polynomial which is constructed from a training data set. Results: A total of 42 CBCT data sets of real clinical pre-operative and post-operative representations from 21 patients were used. Eight data sets were used for training the system and the rest for testing. Conclusions: The proposed methodology was successfully applied to CBCT data sets, producing corresponding panoramic images, suitable for examining pre-operatively and post-operatively the patients' maxillary and mandibular regions. PMID:28112548

2D and 3D visualization methods of endoscopic panoramic bladder images

NASA Astrophysics Data System (ADS)

Behrens, Alexander; Heisterklaus, Iris; Müller, Yannick; Stehle, Thomas; Gross, Sebastian; Aach, Til

2011-03-01

While several mosaicking algorithms have been developed to compose endoscopic images of the internal urinary bladder wall into panoramic images, the quantitative evaluation of these output images in terms of geometrical distortions have often not been discussed. However, the visualization of the distortion level is highly desired for an objective image-based medical diagnosis. Thus, we present in this paper a method to create quality maps from the characteristics of transformation parameters, which were applied to the endoscopic images during the registration process of the mosaicking algorithm. For a global first view impression, the quality maps are laid over the panoramic image and highlight image regions in pseudo-colors according to their local distortions. This illustration supports then surgeons to identify geometrically distorted structures easily in the panoramic image, which allow more objective medical interpretations of tumor tissue in shape and size. Aside from introducing quality maps in 2-D, we also discuss a visualization method to map panoramic images onto a 3-D spherical bladder model. Reference points are manually selected by the surgeon in the panoramic image and the 3-D model. Then the panoramic image is mapped by the Hammer-Aitoff equal-area projection onto the 3-D surface using texture mapping. Finally the textured bladder model can be freely moved in a virtual environment for inspection. Using a two-hemisphere bladder representation, references between panoramic image regions and their corresponding space coordinates within the bladder model are reconstructed. This additional spatial 3-D information thus assists the surgeon in navigation, documentation, as well as surgical planning.

Fragile X syndrome: panoramic radiographic evaluation of dental anomalies, dental mineralization stage, and mandibular angle

PubMed Central

Sabbagh-Haddad, Aida; Haddad, Denise Sabbagh; Michel-Crosato, Edgard; Arita, Emiko Saito

2016-01-01

ABSTRACT Fragile X syndrome (FXS) is a disorder linked to the chromosome X long arm (Xq27.3), which is identified by a constriction named fragile site. It determines various changes, such as behavioral or emotional problems, learning difficulties, and intellectual disabilities. Craniofacial abnormalities such as elongated and narrow face, prominent forehead, broad nose, large and prominent ear pavilions, strabismus, and myopia are frequent characteristics. Regarding the oral aspects, deep and high-arched palate, mandibular prognathism, and malocclusion are also observed. Objective: The purpose of this study was to evaluate the dental radiographic characteristics as described in 40 records of patients with panoramic radiography. Material and Methods: The patients were in the range of 6–17 years old, and were divided into two groups (20 subjects who were compatible with the normality standard and 20 individuals diagnosed with the FXS), which were matched for gender and age. Analysis of the panoramic radiographic examination involved the evaluation of dental mineralization stage, mandibular angle size, and presence of dental anomalies in both deciduous and permanent dentitions. Results: The results of radiographic evaluation demonstrated that the chronology of tooth eruption of all third and second lower molars is anticipated in individuals with FXS (p<0.05). In this group, supernumerary deciduous teeth (2.83%), giroversion of permanent teeth (2.31%), and partial anodontia (1.82%) were the most frequent dental anomalies. In addition, an increase was observed in the mandibular angle size in the FXS group (p<0.05). Conclusion: We conclude that knowledge of dental radiographic changes is of great importance for dental surgeons to plan the treatment of these individuals. PMID:27812623

Quality metric for spherical panoramic video

NASA Astrophysics Data System (ADS)

Zakharchenko, Vladyslav; Choi, Kwang Pyo; Park, Jeong Hoon

2016-09-01

Virtual reality (VR)/ augmented reality (AR) applications allow users to view artificial content of a surrounding space simulating presence effect with a help of special applications or devices. Synthetic contents production is well known process form computer graphics domain and pipeline has been already fixed in the industry. However emerging multimedia formats for immersive entertainment applications such as free-viewpoint television (FTV) or spherical panoramic video require different approaches in content management and quality assessment. The international standardization on FTV has been promoted by MPEG. This paper is dedicated to discussion of immersive media distribution format and quality estimation process. Accuracy and reliability of the proposed objective quality estimation method had been verified with spherical panoramic images demonstrating good correlation results with subjective quality estimation held by a group of experts.

TU-FG-209-09: Mathematical Estimation and Experimental Measurement of Patient Free-In-Air Skin Entrance Exposure During a Panoramic Dental X-Ray Procedure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Errico, A; Behrman, R; Li, B

Purpose: To develop a simple mathematical model for estimating the patient free-in-air skin entrance exposure (SEE) during a panoramic dental x-ray that does not require the use of a head phantom. This eliminates issues associated with phantom centering and the mounting of a detector on the phantom for routine QC testing. Methods: We used a Sirona Orthophos XG panoramic radiographic unit and a Radcal Accu-Gold system for this study. A solid state detector was attached over the slit of the Orthophos’ sensor with the help of a custom-built jig. A single measurement of the free-in-air exposure at this position wasmore » taken over a full panoramic scan. A mathematical model for estimating the SEE was developed based upon this measurement, the system geometry, x-ray field beam width, and x-ray sweep angle. To validate the model, patient geometry was simulated by a 16 cm diameter PMMA CTDI phantom centered at the machine’s isocenter. Measurements taken on the phantom’s surface were made using a solid state detector with lead backing, an ion chamber, and the ion chamber with the phantom wrapped in lead to mitigate backscatter. Measurements were taken near the start position of the tube and at 90 degrees from the start position. Results: Using the solid state detector, the average SEE was 23.5+/−0.02 mR and 55.5+/−0.08 mR at 64 kVp and 73 kVp, respectively. With the lead-wrapping, the measurements from the ion chamber matched those of the solid state detector to within 0.1%. Preliminary results gave the difference between the mathematical model and the phantom measurements to be approximately 5% at both kVps. Conclusion: Reasonable estimates of patient SEE for panoramic dental radiography can be made using a simple mathematical model without the need for a head phantom.« less

Proton radiography based on near-threshold Cerenkov radiation

DOEpatents

van Bibber, Karl A.; Dietrich, Frank S.

2003-01-01

A Cerenkov imaging system for charged particle radiography that determines the energy loss of the charged particle beam passing through an object. This energy loss information provides additional detail on target densities when used with traditional radiographic techniques like photon or x-ray radiography. In this invention a probe beam of 800 MeV to 50 GeV/c charged particles is passed through an object to be imaged, an imaging magnetic spectrometer, to a silicon aerogel Cerenkov radiator where the charged particles emitted Cerenkov light proportional to their velocity. At the same beam focal plane, a particle scintillator produces a light output proportional to the incident beam flux. Optical imaging systems relay the Cerenkov and scintillator information to CCD's or other measurement equipment. A ratio between the Cerenkov and scintillator is formed, which is directly proportional to the line density of the object for each pixel measured. By rotating the object, tomographic radiography may be performed. By applying pulses of beam, discrete time-step movies of dynamic objects may be made.

Real-time radiography at the NECTAR facility

NASA Astrophysics Data System (ADS)

Bücherl, T.; Lierse von Gostomski, Ch.

2011-09-01

A feasibility study has shown that real-time radiography using fission neutrons is possible at the NECTAR facility, when using an improved detection system for fast variations (Bücherl et al., 2009 [1]). Continuing this study, real-time measurements of slowly varying processes like the water uptake in medium sized trunks (diameter about 12 cm) and of slow periodic processes (e.g. a slowly rotating iron disk) are investigated successfully using the existing detection system.

Automatic Synthesis of Panoramic Radiographs from Dental Cone Beam Computed Tomography Data.

PubMed

Luo, Ting; Shi, Changrong; Zhao, Xing; Zhao, Yunsong; Xu, Jinqiu

2016-01-01

In this paper, we propose an automatic method of synthesizing panoramic radiographs from dental cone beam computed tomography (CBCT) data for directly observing the whole dentition without the superimposition of other structures. This method consists of three major steps. First, the dental arch curve is generated from the maximum intensity projection (MIP) of 3D CBCT data. Then, based on this curve, the long axial curves of the upper and lower teeth are extracted to create a 3D panoramic curved surface describing the whole dentition. Finally, the panoramic radiograph is synthesized by developing this 3D surface. Both open-bite shaped and closed-bite shaped dental CBCT datasets were applied in this study, and the resulting images were analyzed to evaluate the effectiveness of this method. With the proposed method, a single-slice panoramic radiograph can clearly and completely show the whole dentition without the blur and superimposition of other dental structures. Moreover, thickened panoramic radiographs can also be synthesized with increased slice thickness to show more features, such as the mandibular nerve canal. One feature of the proposed method is that it is automatically performed without human intervention. Another feature of the proposed method is that it requires thinner panoramic radiographs to show the whole dentition than those produced by other existing methods, which contributes to the clarity of the anatomical structures, including the enamel, dentine and pulp. In addition, this method can rapidly process common dental CBCT data. The speed and image quality of this method make it an attractive option for observing the whole dentition in a clinical setting.

Registration of Panoramic/Fish-Eye Image Sequence and LiDAR Points Using Skyline Features

PubMed Central

Zhu, Ningning; Jia, Yonghong; Ji, Shunping

2018-01-01

We propose utilizing a rigorous registration model and a skyline-based method for automatic registration of LiDAR points and a sequence of panoramic/fish-eye images in a mobile mapping system (MMS). This method can automatically optimize original registration parameters and avoid the use of manual interventions in control point-based registration methods. First, the rigorous registration model between the LiDAR points and the panoramic/fish-eye image was built. Second, skyline pixels from panoramic/fish-eye images and skyline points from the MMS’s LiDAR points were extracted, relying on the difference in the pixel values and the registration model, respectively. Third, a brute force optimization method was used to search for optimal matching parameters between skyline pixels and skyline points. In the experiments, the original registration method and the control point registration method were used to compare the accuracy of our method with a sequence of panoramic/fish-eye images. The result showed: (1) the panoramic/fish-eye image registration model is effective and can achieve high-precision registration of the image and the MMS’s LiDAR points; (2) the skyline-based registration method can automatically optimize the initial attitude parameters, realizing a high-precision registration of a panoramic/fish-eye image and the MMS’s LiDAR points; and (3) the attitude correction values of the sequences of panoramic/fish-eye images are different, and the values must be solved one by one. PMID:29883431

Line-Based Registration of Panoramic Images and LiDAR Point Clouds for Mobile Mapping.

PubMed

Cui, Tingting; Ji, Shunping; Shan, Jie; Gong, Jianya; Liu, Kejian

2016-12-31

For multi-sensor integrated systems, such as the mobile mapping system (MMS), data fusion at sensor-level, i.e., the 2D-3D registration between an optical camera and LiDAR, is a prerequisite for higher level fusion and further applications. This paper proposes a line-based registration method for panoramic images and a LiDAR point cloud collected by a MMS. We first introduce the system configuration and specification, including the coordinate systems of the MMS, the 3D LiDAR scanners, and the two panoramic camera models. We then establish the line-based transformation model for the panoramic camera. Finally, the proposed registration method is evaluated for two types of camera models by visual inspection and quantitative comparison. The results demonstrate that the line-based registration method can significantly improve the alignment of the panoramic image and the LiDAR datasets under either the ideal spherical or the rigorous panoramic camera model, with the latter being more reliable.

Line-Based Registration of Panoramic Images and LiDAR Point Clouds for Mobile Mapping

PubMed Central

Cui, Tingting; Ji, Shunping; Shan, Jie; Gong, Jianya; Liu, Kejian

2016-01-01

For multi-sensor integrated systems, such as the mobile mapping system (MMS), data fusion at sensor-level, i.e., the 2D-3D registration between an optical camera and LiDAR, is a prerequisite for higher level fusion and further applications. This paper proposes a line-based registration method for panoramic images and a LiDAR point cloud collected by a MMS. We first introduce the system configuration and specification, including the coordinate systems of the MMS, the 3D LiDAR scanners, and the two panoramic camera models. We then establish the line-based transformation model for the panoramic camera. Finally, the proposed registration method is evaluated for two types of camera models by visual inspection and quantitative comparison. The results demonstrate that the line-based registration method can significantly improve the alignment of the panoramic image and the LiDAR datasets under either the ideal spherical or the rigorous panoramic camera model, with the latter being more reliable. PMID:28042855

Enhancement of panoramic image resolution based on swift interpolation of Bezier surface

NASA Astrophysics Data System (ADS)

Xiao, Xiao; Yang, Guo-guang; Bai, Jian

2007-01-01

Panoramic annular lens project the view of the entire 360 degrees around the optical axis onto an annular plane based on the way of flat cylinder perspective. Due to the infinite depth of field and the linear mapping relationship between an object and an image, the panoramic imaging system plays important roles in the applications of robot vision, surveillance and virtual reality. An annular image needs to be unwrapped to conventional rectangular image without distortion, in which interpolation algorithm is necessary. Although cubic splines interpolation can enhance the resolution of unwrapped image, it occupies too much time to be applied in practices. This paper adopts interpolation method based on Bezier surface and proposes a swift interpolation algorithm for panoramic image, considering the characteristic of panoramic image. The result indicates that the resolution of the image is well enhanced compared with the image by cubic splines and bilinear interpolation. Meanwhile the time consumed is shortened up by 78% than the time consumed cubic interpolation.

Research on the framework and key technologies of panoramic visualization for smart distribution network

NASA Astrophysics Data System (ADS)

Du, Jian; Sheng, Wanxing; Lin, Tao; Lv, Guangxian

2018-05-01

Nowadays, the smart distribution network has made tremendous progress, and the business visualization becomes even more significant and indispensable. Based on the summarization of traditional visualization technologies and demands of smart distribution network, a panoramic visualization application is proposed in this paper. The overall architecture, integrated architecture and service architecture of panoramic visualization application is firstly presented. Then, the architecture design and main functions of panoramic visualization system are elaborated in depth. In addition, the key technologies related to the application is discussed briefly. At last, two typical visualization scenarios in smart distribution network, which are risk warning and fault self-healing, proves that the panoramic visualization application is valuable for the operation and maintenance of the distribution network.

Range and Panoramic Image Fusion Into a Textured Range Image for Culture Heritage Documentation

NASA Astrophysics Data System (ADS)

Bila, Z.; Reznicek, J.; Pavelka, K.

2013-07-01

This paper deals with a fusion of range and panoramic images, where the range image is acquired by a 3D laser scanner and the panoramic image is acquired with a digital still camera mounted on a panoramic head and tripod. The fused resulting dataset, called "textured range image", provides more reliable information about the investigated object for conservators and historians, than using both datasets separately. A simple example of fusion of a range and panoramic images, both obtained in St. Francis Xavier Church in town Opařany, is given here. Firstly, we describe the process of data acquisition, then the processing of both datasets into a proper format for following fusion and the process of fusion. The process of fusion can be divided into a two main parts: transformation and remapping. In the first, transformation, part, both images are related by matching similar features detected on both images with a proper detector, which results in transformation matrix enabling transformation of the range image onto a panoramic image. Then, the range data are remapped from the range image space into a panoramic image space and stored as an additional "range" channel. The process of image fusion is validated by comparing similar features extracted on both datasets.

Achieving real-time capsule endoscopy (CE) video visualization through panoramic imaging

NASA Astrophysics Data System (ADS)

Yi, Steven; Xie, Jean; Mui, Peter; Leighton, Jonathan A.

2013-02-01

In this paper, we mainly present a novel and real-time capsule endoscopy (CE) video visualization concept based on panoramic imaging. Typical CE videos run about 8 hours and are manually reviewed by physicians to locate diseases such as bleedings and polyps. To date, there is no commercially available tool capable of providing stabilized and processed CE video that is easy to analyze in real time. The burden on physicians' disease finding efforts is thus big. In fact, since the CE camera sensor has a limited forward looking view and low image frame rate (typical 2 frames per second), and captures very close range imaging on the GI tract surface, it is no surprise that traditional visualization method based on tracking and registration often fails to work. This paper presents a novel concept for real-time CE video stabilization and display. Instead of directly working on traditional forward looking FOV (field of view) images, we work on panoramic images to bypass many problems facing traditional imaging modalities. Methods on panoramic image generation based on optical lens principle leading to real-time data visualization will be presented. In addition, non-rigid panoramic image registration methods will be discussed.

A Comparison of the AVS-9 and the Panoramic Night Vision Goggles During Rotorcraft Hover and Landing

NASA Technical Reports Server (NTRS)

Szoboszlay, Zoltan; Haworth, Loran; Simpson, Carol

2000-01-01

A flight test was conducted to assess any differences in pilot-vehicle performance and pilot opinion between the use of a current generation night vision goggle (the AVS-9) and one variant of the prototype panoramic night vision goggle (the PNVGII). The panoramic goggle has more than double the horizontal field-of-view of the AVS-9, but reduced image quality. Overall the panoramic goggles compared well to the AVS-9 goggles. However, pilot comment and data are consistent with the assertion that some of the benefits of additional field-of-view with the panoramic goggles were negated by the reduced image quality of the particular variant of the panoramic goggles tested.

Panoramic autofluorescence: highlighting retinal pathology.

PubMed

Slotnick, Samantha; Sherman, Jerome

2012-05-01

Recent technological advances in fundus autofluorescence (FAF) are providing new opportunities for insight into retinal physiology and pathophysiology. FAF provides distinctly different imaging information than standard photography or color separation. A review of the basis for this imaging technology is included to help the clinician understand how to interpret FAF images. Cases are presented to illustrate image interpretation. Optos, which manufactures equipment for simultaneous panoramic imaging, has recently outfitted several units with AF capabilities. Six cases are presented in which panoramic autofluorescent (PAF) images highlight retinal pathology, using Optos' Ultra-Widefield technology. Supportive imaging technologies, such as Optomap® images and spectral domain optical coherence tomography (SD-OCT), are used to assist in the clinical interpretation of retinal pathology detected on PAF. Hypofluorescent regions on FAF are identified to occur along with a disruption in the photoreceptors and/or retinal pigment epithelium, as borne out on SD-OCT. Hyperfluorescent regions on FAF occur at the advancing zones of retinal degeneration, indicating impending damage. PAF enables such inferences to be made in retinal areas which lie beyond the reach of SD-OCT imaging. PAF also enhances clinical pattern recognition over a large area and in comparison with the fellow eye. Symmetric retinal degenerations often occur with genetic conditions, such as retinitis pigmentosa, and may impel the clinician to recommend genetic testing. Autofluorescent ophthalmoscopy is a non-invasive procedure that can detect changes in metabolic activity at the retinal pigment epithelium before clinical ophthalmoscopy. Already, AF is being used as an adjunct technology to fluorescein angiography in cases of age-related macular degeneration. Both hyper- and hypoautofluorescent changes are indicative of pathology. Peripheral retinal abnormalities may precede central retinal impacts, potentially

Evaluation of the diagnostic yield of dental radiography and cone-beam computed tomography for the identification of dental disorders in small to medium-sized brachycephalic dogs.

PubMed

Döring, Sophie; Arzi, Boaz; Hatcher, David C; Kass, Philip H; Verstraete, Frank J M

2018-01-01

OBJECTIVE To evaluate the diagnostic yield of dental radiography (Rad method) and cone-beam CT (CBCT) methods for the identification of 31 predefined dental disorders in brachycephalic dogs. ANIMALS 19 client-owned brachycephalic dogs admitted for evaluation and treatment of dental disease. PROCEDURES 31 predefined dental disorders were evaluated separately and scored by use of dental radiography and 3 CBCT software modules (serial CBCT slices and custom cross sections, tridimensional rendering, and reconstructed panoramic views). A qualitative scoring system was used. Dental disorders were grouped into 10 categories for statistical analysis. Point of reference for presence or absence of a dental disorder was determined as the method that could be used to clearly identify the disorder as being present. Accuracy, sensitivity, specificity, and positive and negative predictive values were calculated with the McNemar χ 2 test of marginal homogeneity of paired data. RESULTS When all 3 CBCT methods were used in combination, the diagnostic yield of CBCT was significantly higher than that of dental radiography for 4 of 10 categories (abnormal eruption, abnormally shaped roots, periodontitis, and tooth resorption) and higher, although not significantly so, for all categories, except for 1 (loss of tooth integrity). CONCLUSIONS AND CLINICAL RELEVANCE CBCT provided more detailed information than did dental radiography. Therefore, CBCT would be better suited for use in diagnosing dental disorders in brachycephalic dogs.

An in vitro comparison of subjective image quality of panoramic views acquired via 2D or 3D imaging.

PubMed

Pittayapat, P; Galiti, D; Huang, Y; Dreesen, K; Schreurs, M; Souza, P Couto; Rubira-Bullen, I R F; Westphalen, F H; Pauwels, R; Kalema, G; Willems, G; Jacobs, R

2013-01-01

The objective of this study is to compare subjective image quality and diagnostic validity of cone-beam CT (CBCT) panoramic reformatting with digital panoramic radiographs. Four dry human skulls and two formalin-fixed human heads were scanned using nine different CBCTs, one multi-slice CT (MSCT) and one standard digital panoramic device. Panoramic views were generated from CBCTs in four slice thicknesses. Seven observers scored image quality and visibility of 14 anatomical structures. Four observers repeated the observation after 4 weeks. Digital panoramic radiographs showed significantly better visualization of anatomical structures except for the condyle. Statistical analysis of image quality showed that the 3D imaging modalities (CBCTs and MSCT) were 7.3 times more likely to receive poor scores than the 2D modality. Yet, image quality from NewTom VGi® and 3D Accuitomo 170® was almost equivalent to that of digital panoramic radiographs with respective odds ratio estimates of 1.2 and 1.6 at 95% Wald confidence limits. A substantial overall agreement amongst observers was found. Intra-observer agreement was moderate to substantial. While 2D-panoramic images are significantly better for subjective diagnosis, 2/3 of the 3D-reformatted panoramic images are moderate or good for diagnostic purposes. Panoramic reformattings from particular CBCTs are comparable to digital panoramic images concerning the overall image quality and visualization of anatomical structures. This clinically implies that a 3D-derived panoramic view can be generated for diagnosis with a recommended 20-mm slice thickness, if CBCT data is a priori available for other purposes.

Registration of Vehicle-Borne Point Clouds and Panoramic Images Based on Sensor Constellations

PubMed Central

Yao, Lianbi; Wu, Hangbin; Li, Yayun; Meng, Bin; Qian, Jinfei; Liu, Chun; Fan, Hongchao

2017-01-01

A mobile mapping system (MMS) is usually utilized to collect environmental data on and around urban roads. Laser scanners and panoramic cameras are the main sensors of an MMS. This paper presents a new method for the registration of the point clouds and panoramic images based on sensor constellation. After the sensor constellation was analyzed, a feature point, the intersection of the connecting line between the global positioning system (GPS) antenna and the panoramic camera with a horizontal plane, was utilized to separate the point clouds into blocks. The blocks for the central and sideward laser scanners were extracted with the segmentation feature points. Then, the point clouds located in the blocks were separated from the original point clouds. Each point in the blocks was used to find the accurate corresponding pixel in the relative panoramic images via a collinear function, and the position and orientation relationship amongst different sensors. A search strategy is proposed for the correspondence of laser scanners and lenses of panoramic cameras to reduce calculation complexity and improve efficiency. Four cases of different urban road types were selected to verify the efficiency and accuracy of the proposed method. Results indicate that most of the point clouds (with an average of 99.7%) were successfully registered with the panoramic images with great efficiency. Geometric evaluation results indicate that horizontal accuracy was approximately 0.10–0.20 m, and vertical accuracy was approximately 0.01–0.02 m for all cases. Finally, the main factors that affect registration accuracy, including time synchronization amongst different sensors, system positioning and vehicle speed, are discussed. PMID:28398256

Registration of Vehicle-Borne Point Clouds and Panoramic Images Based on Sensor Constellations.

PubMed

Yao, Lianbi; Wu, Hangbin; Li, Yayun; Meng, Bin; Qian, Jinfei; Liu, Chun; Fan, Hongchao

2017-04-11

A mobile mapping system (MMS) is usually utilized to collect environmental data on and around urban roads. Laser scanners and panoramic cameras are the main sensors of an MMS. This paper presents a new method for the registration of the point clouds and panoramic images based on sensor constellation. After the sensor constellation was analyzed, a feature point, the intersection of the connecting line between the global positioning system (GPS) antenna and the panoramic camera with a horizontal plane, was utilized to separate the point clouds into blocks. The blocks for the central and sideward laser scanners were extracted with the segmentation feature points. Then, the point clouds located in the blocks were separated from the original point clouds. Each point in the blocks was used to find the accurate corresponding pixel in the relative panoramic images via a collinear function, and the position and orientation relationship amongst different sensors. A search strategy is proposed for the correspondence of laser scanners and lenses of panoramic cameras to reduce calculation complexity and improve efficiency. Four cases of different urban road types were selected to verify the efficiency and accuracy of the proposed method. Results indicate that most of the point clouds (with an average of 99.7%) were successfully registered with the panoramic images with great efficiency. Geometric evaluation results indicate that horizontal accuracy was approximately 0.10-0.20 m, and vertical accuracy was approximately 0.01-0.02 m for all cases. Finally, the main factors that affect registration accuracy, including time synchronization amongst different sensors, system positioning and vehicle speed, are discussed.

Low-cost panoramic infrared surveillance system

NASA Astrophysics Data System (ADS)

Kecskes, Ian; Engel, Ezra; Wolfe, Christopher M.; Thomson, George

2017-05-01

A nighttime surveillance concept consisting of a single surface omnidirectional mirror assembly and an uncooled Vanadium Oxide (VOx) longwave infrared (LWIR) camera has been developed. This configuration provides a continuous field of view spanning 360° in azimuth and more than 110° in elevation. Both the camera and the mirror are readily available, off-the-shelf, inexpensive products. The mirror assembly is marketed for use in the visible spectrum and requires only minor modifications to function in the LWIR spectrum. The compactness and portability of this optical package offers significant advantages over many existing infrared surveillance systems. The developed system was evaluated on its ability to detect moving, human-sized heat sources at ranges between 10 m and 70 m. Raw camera images captured by the system are converted from rectangular coordinates in the camera focal plane to polar coordinates and then unwrapped into the users azimuth and elevation system. Digital background subtraction and color mapping are applied to the images to increase the users ability to extract moving items from background clutter. A second optical system consisting of a commercially available 50 mm f/1.2 ATHERM lens and a second LWIR camera is used to examine the details of objects of interest identified using the panoramic imager. A description of the components of the proof of concept is given, followed by a presentation of raw images taken by the panoramic LWIR imager. A description of the method by which these images are analyzed is given, along with a presentation of these results side-by-side with the output of the 50 mm LWIR imager and a panoramic visible light imager. Finally, a discussion of the concept and its future development are given.

A panoramic imaging system based on fish-eye lens

NASA Astrophysics Data System (ADS)

Wang, Ye; Hao, Chenyang

2017-10-01

Panoramic imaging has been closely watched as one of the major technologies of AR and VR. Mainstream panoramic imaging techniques lenses include fish-eye lenses, image splicing, and catadioptric imaging system. Meanwhile, fish-eyes are widely used in the big picture video surveillance. The advantage of fish-eye lenses is that they are easy to operate and cost less, but how to solve the image distortion of fish-eye lenses has always been a very important topic. In this paper, the image calibration algorithm of fish-eye lens is studied by comparing the method of interpolation, bilinear interpolation and double three interpolation, which are used to optimize the images.

Photographic technology development project: Timber typing in the Tahoe Basin using high altitude panoramic photography

NASA Technical Reports Server (NTRS)

Ward, J. F.

1981-01-01

Procedures were developed and tested for using KA-80A optical bar camera panoramic photography for timber typing forest land and classifying nonforest land. The study area was the south half of the Lake Tahoe Basin Management Unit. Final products from this study include four timber type map overlays on 1:24,000 orthophoto maps. The following conclusions can be drawn from this study: (1) established conventional timber typing procedures can be used on panoramic photography if the necessary equipment is available, (2) The classification and consistency results warrant further study in using panoramic photography for timber typing; and (3) timber type mapping can be done as fast or faster with panoramic photography than with resource photography while maintaining comparable accuracy.

Femoral neck radiography: effect of flexion on visualization.

PubMed

Garry, Steven C; Jhangri, Gian S; Lambert, Robert G W

2005-06-01

To determine whether flexion improves radiographic visualization of the femoral neck when the femur is externally rotated. Five human femora, with varying neck-shaft and anteversion angles, were measured and immobilized. Degree of flexion required to bring the femoral neck horizontal was measured, varying the rotation. Next, one bone was radiographed in 16 positions, varying rotation in 15 degrees and flexion in 10 degrees increments. Radiographs were presented in randomized blinded fashion to 15 staff radiologists for scoring of femoral neck visualization. Following this, all 5 bones were radiographed in 4 positions of rotation and at 0 degree and 20 degrees flexion, and blinded randomized review of radiographs was repeated. Comparisons between angles and rotations were made using the Mann-Whitney test. The flexion angle required to bring the long axis of the femoral neck horizontal correlated directly with the degree of external rotation (p < 0.05). Visualization of the femoral neck in the extended position progressively deteriorated from 15 degrees internal rotation to 30 degrees external rotation (p < 0.01). However, when 20 degrees flexion was applied to bones in external rotation, visualization significantly improved at 15 degrees (p < 0.05) and 30 degrees (p < 0.01). Flexion of the externally rotated femur can bring the femoral neck into horizontal alignment, and a relatively small amount (20 degrees) of flexion can significantly improve radiographic visualization. This manoeuvre could be useful for radiography of the femoral neck when initial radiographs are inadequate because of external rotation of the leg.

Panoramic radiographic predictors of mandibular third molar eruption.

PubMed

Niedzielska, Iwona Anna; Drugacz, Jan; Kus, Nina; Kreska, Joanna

2006-08-01

Third molar (M3) eruption can be problematic. According to some orthodontic surgeons, the teeth are capable of aggravating the average crowding level in the dental arch. The question is whether it might be possible to give a prognosis for ultimate M3 position in the arch and make an early decision to extract or retain them. The purpose of the study was to determine which measurements made on panoramic tomograms might facilitate prognosis for M3 position in the dental arch over the years. The investigation involved 64 patients who had been enrolled to the study group 10 years earlier, ie, in 1993, when an analysis had been carried out regarding M3 effect on dental arch crowding. At that time panoramic tomograms had been taken, and dental casts made. The procedures were repeated in 2003. The following measurements were taken at baseline (1993) and at the end of the study (2003): (1)/the retromolar space to lower third molar crown width, (2) third molar angulation to the base of the mandible, and (3) third molar to second molar inclination. At some defined values of the Ganss ratio, and M3 inclination to mandibular base and second molar, it is possible to predict potential lower third molar alignment in the dental arch using a panoramic radiograph.

Mobile Panoramic Video Applications for Learning

ERIC Educational Resources Information Center

Multisilta, Jari

2014-01-01

The use of videos on the internet has grown significantly in the last few years. For example, Khan Academy has a large collection of educational videos, especially on STEM subjects, available for free on the internet. Professional panoramic video cameras are expensive and usually not easy to carry because of the large size of the equipment.…

Panoramic 3D Reconstruction by Fusing Color Intensity and Laser Range Data

NASA Astrophysics Data System (ADS)

Jiang, Wei; Lu, Jian

Technology for capturing panoramic (360 degrees) three-dimensional information in a real environment have many applications in fields: virtual and complex reality, security, robot navigation, and so forth. In this study, we examine an acquisition device constructed of a regular CCD camera and a 2D laser range scanner, along with a technique for panoramic 3D reconstruction using a data fusion algorithm based on an energy minimization framework. The acquisition device can capture two types of data of a panoramic scene without occlusion between two sensors: a dense spatio-temporal volume from a camera and distance information from a laser scanner. We resample the dense spatio-temporal volume for generating a dense multi-perspective panorama that has equal spatial resolution to that of the original images acquired using a regular camera, and also estimate a dense panoramic depth-map corresponding to the generated reference panorama by extracting trajectories from the dense spatio-temporal volume with a selecting camera. Moreover, for determining distance information robustly, we propose a data fusion algorithm that is embedded into an energy minimization framework that incorporates active depth measurements using a 2D laser range scanner and passive geometry reconstruction from an image sequence obtained using the CCD camera. Thereby, measurement precision and robustness can be improved beyond those available by conventional methods using either passive geometry reconstruction (stereo vision) or a laser range scanner. Experimental results using both synthetic and actual images show that our approach can produce high-quality panoramas and perform accurate 3D reconstruction in a panoramic environment.

Design, demonstration and testing of low F-number LWIR panoramic imaging relay optics

NASA Astrophysics Data System (ADS)

Furxhi, Orges; Frascati, Joe; Driggers, Ronald

2018-04-01

Panoramic imaging is inherently wide field of view. High sensitivity uncooled Long Wave Infrared (LWIR) imaging requires low F-number optics. These two requirements result in short back working distance designs that, in addition to being costly, are challenging to integrate with commercially available uncooled LWIR cameras and cores. Common challenges include the relocation of the shutter flag, custom calibration of the camera dynamic range and NUC tables, focusing, and athermalization. Solutions to these challenges add to the system cost and make panoramic uncooled LWIR cameras commercially unattractive. In this paper, we present the design of Panoramic Imaging Relay Optics (PIRO) and show imagery and test results with one of the first prototypes. PIRO designs use several reflective surfaces (generally two) to relay a panoramic scene onto a real, donut-shaped image. The PIRO donut is imaged on the focal plane of the camera using a commercially-off-the-shelf (COTS) low F-number lens. This approach results in low component cost and effortless integration with pre-calibrated commercially available cameras and lenses.

Diagnostic Accuracy of Cone-beam Computed Tomography and Conventional Radiography on Apical Periodontitis: A Systematic Review and Meta-analysis.

PubMed

Leonardi Dutra, Kamile; Haas, Letícia; Porporatti, André Luís; Flores-Mir, Carlos; Nascimento Santos, Juliana; Mezzomo, Luis André; Corrêa, Márcio; De Luca Canto, Graziela

2016-03-01

Endodontic diagnosis depends on accurate radiographic examination. Assessment of the location and extent of apical periodontitis (AP) can influence treatment planning and subsequent treatment outcomes. Therefore, this systematic review and meta-analysis assessed the diagnostic accuracy of conventional radiography and cone-beam computed tomographic (CBCT) imaging on the discrimination of AP from no lesion. Eight electronic databases with no language or time limitations were searched. Articles in which the primary objective was to evaluate the accuracy (sensitivity and specificity) of any type of radiographic technique to assess AP in humans were selected. The gold standard was the histologic examination for actual AP (in vivo) or in situ visualization of bone defects for induced artificial AP (in vitro). Accuracy measurements described in the studies were transformed to construct receiver operating characteristic curves and forest plots with the aid of Review Manager v.5.2 (The Nordic Cochrane Centre, Copenhagen, Denmark) and MetaDisc v.1.4. software (Unit of Clinical Biostatistics Team of the Ramón y Cajal Hospital, Madrid, Spain). The methodology of the selected studies was evaluated using the Quality Assessment Tool for Diagnostic Accuracy Studies-2. Only 9 studies met the inclusion criteria and were subjected to a qualitative analysis. A meta-analysis was conducted on 6 of these articles. All of these articles studied artificial AP with induced bone defects. The accuracy values (area under the curve) were 0.96 for CBCT imaging, 0.73 for conventional periapical radiography, and 0.72 for digital periapical radiography. No evidence was found for panoramic radiography. Periapical radiographs (digital and conventional) reported good diagnostic accuracy on the discrimination of artificial AP from no lesions, whereas CBCT imaging showed excellent accuracy values. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Axial Tomography from Digitized Real Time Radiography

DOE R&D Accomplishments Database

Zolnay, A. S.; McDonald, W. M.; Doupont, P. A.; McKinney, R. L.; Lee, M. M.

1985-01-18

Axial tomography from digitized real time radiographs provides a useful tool for industrial radiography and tomography. The components of this system are: x-ray source, image intensifier, video camera, video line extractor and digitizer, data storage and reconstruction computers. With this system it is possible to view a two dimensional x-ray image in real time at each angle of rotation and select the tomography plane of interest by choosing which video line to digitize. The digitization of a video line requires less than a second making data acquisition relatively short. Further improvements on this system are planned and initial results are reported.

A note on digital dental radiography in forensic odontology.

PubMed

Chiam, Sher-Lin

2014-09-01

Digital dental radiography, intraoral and extraoral, is becoming more popular in dental practice. It offers convenience, such as lower exposure to radiation, ease of storing of images, and elimination of chemical processing. However, it also has disadvantages and drawbacks. One of these is the potential for confusion of the orientation of the image. This paper outlines one example of this, namely, the lateral inversion of the image. This source of confusion is partly inherent in the older model of phosphor storage plates (PSPs), as they allow both sides to be exposed without clue to the fact that the image is acquired on the wrong side. The native software allows digital manipulation of the X-ray image, permitting both rotation and inversion. Attempts to orientate the X-ray according to the indicator incorporated on the plate can then sometimes lead to inadvertent lateral inversion of the image. This article discusses the implications of such mistakes in dental digital radiography to forensic odontology and general dental practice.

Matching Real and Synthetic Panoramic Images Using a Variant of Geometric Hashing

NASA Astrophysics Data System (ADS)

Li-Chee-Ming, J.; Armenakis, C.

2017-05-01

This work demonstrates an approach to automatically initialize a visual model-based tracker, and recover from lost tracking, without prior camera pose information. These approaches are commonly referred to as tracking-by-detection. Previous tracking-by-detection techniques used either fiducials (i.e. landmarks or markers) or the object's texture. The main contribution of this work is the development of a tracking-by-detection algorithm that is based solely on natural geometric features. A variant of geometric hashing, a model-to-image registration algorithm, is proposed that searches for a matching panoramic image from a database of synthetic panoramic images captured in a 3D virtual environment. The approach identifies corresponding features between the matched panoramic images. The corresponding features are to be used in a photogrammetric space resection to estimate the camera pose. The experiments apply this algorithm to initialize a model-based tracker in an indoor environment using the 3D CAD model of the building.

The Panoramic Camera (PanCam) Instrument for the ESA ExoMars Rover

NASA Astrophysics Data System (ADS)

Griffiths, A.; Coates, A.; Jaumann, R.; Michaelis, H.; Paar, G.; Barnes, D.; Josset, J.

The recently approved ExoMars rover is the first element of the ESA Aurora programme and is slated to deliver the Pasteur exobiology payload to Mars by 2013. The 0.7 kg Panoramic Camera will provide multispectral stereo images with 65° field-of- view (1.1 mrad/pixel) and high resolution (85 µrad/pixel) monoscopic "zoom" images with 5° field-of-view. The stereo Wide Angle Cameras (WAC) are based on Beagle 2 Stereo Camera System heritage. The Panoramic Camera instrument is designed to fulfil the digital terrain mapping requirements of the mission as well as providing multispectral geological imaging, colour and stereo panoramic images, solar images for water vapour abundance and dust optical depth measurements and to observe retrieved subsurface samples before ingestion into the rest of the Pasteur payload. Additionally the High Resolution Camera (HRC) can be used for high resolution imaging of interesting targets detected in the WAC panoramas and of inaccessible locations on crater or valley walls.

8. VIEW OF RADIOGRAPHY EQUIPMENT, TEST METHODS INCLUDED RADIOGRAPHY AND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. VIEW OF RADIOGRAPHY EQUIPMENT, TEST METHODS INCLUDED RADIOGRAPHY AND BETA BACKSCATTERING. (7/13/56) - Rocky Flats Plant, Non-Nuclear Production Facility, South of Cottonwood Avenue, west of Seventh Avenue & east of Building 460, Golden, Jefferson County, CO

INDUSTRIAL RADIOGRAPHY INSTRUCTOR'S GUIDE.

ERIC Educational Resources Information Center

Bureau of Adult, Vocational, and Technical Education (DHEW/OE), Washington, DC. Div. of Vocational and Technical Education.

THIS LABORATORY GUIDE WAS DEVELOPED FOR AN 80-HOUR COURSE IN INDUSTRIAL RADIOGRAPHY FOR HIGH SCHOOL GRADUATES TRAINING TO BECOME BEGINNING RADIOGRAPHERS. IT IS USED IN CONJUNCTION WITH TWO OTHER VOLUMES--(1) INDUSTRIAL RADIOGRAPHY INSTRUCTOR'S GUIDE, AND (2) INUDSTRIAL RADIOGRAPHY MANUAL. THE PROGRAM WAS DEVELOPED BY A COMMITTEE OF REPRESENTATIVES…

Panoramic Sinai Peninsula, Red Sea

NASA Image and Video Library

1984-10-13

An excellent panoramic view of the entire Sinai Peninsula (29.0N, 34.0E) and the nearby Nile River Delta and eastern Mediterranean coastal region. The Suez Canal, at the top of the scene just to the right of the Delta, connects the Mediterranean Sea with the Gulf of Suez on the west side of the Sinai Peninsula and the Gulf of Aqaba is on the west where they both flow into the Red Sea. At upper right, is the Dead Sea, Jordan River and Lake Tiberius.

Research diagnostic criteria for temporomandibular disorders (RDC/TMD): development of image analysis criteria and examiner reliability for image analysis.

PubMed

Ahmad, Mansur; Hollender, Lars; Anderson, Quentin; Kartha, Krishnan; Ohrbach, Richard; Truelove, Edmond L; John, Mike T; Schiffman, Eric L

2009-06-01

As part of the Multisite Research Diagnostic Criteria For Temporomandibular Disorders (RDC/TMD) Validation Project, comprehensive temporomandibular joint diagnostic criteria were developed for image analysis using panoramic radiography, magnetic resonance imaging (MRI), and computerized tomography (CT). Interexaminer reliability was estimated using the kappa (kappa) statistic, and agreement between rater pairs was characterized by overall, positive, and negative percent agreement. Computerized tomography was the reference standard for assessing validity of other imaging modalities for detecting osteoarthritis (OA). For the radiologic diagnosis of OA, reliability of the 3 examiners was poor for panoramic radiography (kappa = 0.16), fair for MRI (kappa = 0.46), and close to the threshold for excellent for CT (kappa = 0.71). Using MRI, reliability was excellent for diagnosing disc displacements (DD) with reduction (kappa = 0.78) and for DD without reduction (kappa = 0.94) and good for effusion (kappa = 0.64). Overall percent agreement for pairwise ratings was >or=82% for all conditions. Positive percent agreement for diagnosing OA was 19% for panoramic radiography, 59% for MRI, and 84% for CT. Using MRI, positive percent agreement for diagnoses of any DD was 95% and of effusion was 81%. Negative percent agreement was >or=88% for all conditions. Compared with CT, panoramic radiography and MRI had poor and marginal sensitivity, respectively, but excellent specificity in detecting OA. Comprehensive image analysis criteria for the RDC/TMD Validation Project were developed, which can reliably be used for assessing OA using CT and for disc position and effusion using MRI.

Optics to rectify CORONA panoramic photographs for map making

NASA Astrophysics Data System (ADS)

Hilbert, Robert S.

2006-08-01

In the 1960's, accurate maps of the United States were available to all, from the U.S. Government, but maps of the Soviet Union were not, and in fact were classified. Maps of the Soviet Union were needed by the U.S. Government, including for U.S. targeting of Soviet ICBM sites, and for negotiating the SALT ICBM disarmament treaty. Although mapping cameras were historically frame cameras with low distortion, the CORONA panoramic film coverage was used to identify any ICBM sites. If distortion-free photographs could be produced from this inherently distorted panoramic material, accurate maps could be produced that would be valuable. Use of the stereo photographs from CORONA, for developing accurate topographical maps, was the mission of Itek's Gamma Rectifier. Bob Shannon's department at Itek was responsible for designing the optics for the Gamma Rectifier. He assigned the design to the author. The optical requirements of this system are described along with the optical design solution, which allowed the inherent panoramic distortion of the original photographs to be "rectified" to a very high level of accuracy, in enlarged photographs. These rectifiers were used three shifts a day, for over a decade, and produced the most accurate maps of the earth's surface, that existed at that time. The results facilitated the success of the Strategic Arms Limitation Talks (SALT) Treaty signed by the US and the Soviet Union in 1972, which were verified by "national means of verification" (i.e. space reconnaissance).

63. PANORAMIC VIEW OF HEADWORKS FROM WEST SIDE OF RIVER, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

63. PANORAMIC VIEW OF HEADWORKS FROM WEST SIDE OF RIVER, LOOKING UPSTREAM, Prints No. 173, 174 and 175, November 1903 - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA

Measurement methods and accuracy analysis of Chang'E-5 Panoramic Camera installation parameters

NASA Astrophysics Data System (ADS)

Yan, Wei; Ren, Xin; Liu, Jianjun; Tan, Xu; Wang, Wenrui; Chen, Wangli; Zhang, Xiaoxia; Li, Chunlai

2016-04-01

Chang'E-5 (CE-5) is a lunar probe for the third phase of China Lunar Exploration Project (CLEP), whose main scientific objectives are to implement lunar surface sampling and to return the samples back to the Earth. To achieve these goals, investigation of lunar surface topography and geological structure within sampling area seems to be extremely important. The Panoramic Camera (PCAM) is one of the payloads mounted on CE-5 lander. It consists of two optical systems which installed on a camera rotating platform. Optical images of sampling area can be obtained by PCAM in the form of a two-dimensional image and a stereo images pair can be formed by left and right PCAM images. Then lunar terrain can be reconstructed based on photogrammetry. Installation parameters of PCAM with respect to CE-5 lander are critical for the calculation of exterior orientation elements (EO) of PCAM images, which is used for lunar terrain reconstruction. In this paper, types of PCAM installation parameters and coordinate systems involved are defined. Measurement methods combining camera images and optical coordinate observations are studied for this work. Then research contents such as observation program and specific solution methods of installation parameters are introduced. Parametric solution accuracy is analyzed according to observations obtained by PCAM scientifically validated experiment, which is used to test the authenticity of PCAM detection process, ground data processing methods, product quality and so on. Analysis results show that the accuracy of the installation parameters affects the positional accuracy of corresponding image points of PCAM stereo images within 1 pixel. So the measurement methods and parameter accuracy studied in this paper meet the needs of engineering and scientific applications. Keywords: Chang'E-5 Mission; Panoramic Camera; Installation Parameters; Total Station; Coordinate Conversion

Panoramic ECG display versus conventional ECG: ischaemia detection by critical care nurses.

PubMed

Wilson, Nick; Hassani, Aimen; Gibson, Vanessa; Lightfoot, Timothy; Zizzo, Claudio

2012-01-01

To compare accuracy and certainty of diagnosis of cardiac ischaemia using the Panoramic ECG display tool plus conventional 12-lead electrocardiogram (ECG) versus 12-lead ECG alone by UK critical care nurses who were members of the British Association of Critical Care Nurses (BACCN). Critically ill patients are prone to myocardial ischaemia. Symptoms may be masked by sedation or analgesia, and ECG changes may be the only sign. Critical care nurses have an essential role in detecting ECG changes promptly. Despite this, critical care nurses may lack expertise in interpreting ECGs and myocardial ischaemia often goes undetected by critical care staff. British Association of Critical Care Nurses (BACCN) members were invited to complete an online survey to evaluate the analysis of two sets of eight ECGs displayed alone and with the new display device. Data from 82 participants showed diagnostic accuracy improved from 67·1% reading ECG traces alone, to 96·0% reading ECG plus Panoramic ECG display tool (P < 0·01, significance level α = 0·05). Participants' diagnostic certainty score rose from 41·7% reading ECG alone to 66·8% reading ECG plus Panoramic ECG display tool (P < 0·01, α = 0·05). The Panoramic ECG display tool improves both accuracy and certainty of detecting ST segment changes among critical care nurses, when compared to conventional 12-lead ECG alone. This benefit was greatest with early ischaemic changes. Critical care nurses who are least confident in reading conventional ECGs benefit the most from the new display. Critical care nurses have an essential role in the monitoring of critically ill patients. However, nurses do not always have the expertise to detect subtle ischaemic ECG changes promptly. Introduction of the Panoramic ECG display tool into clinical practice could lead to patients receiving treatment for myocardial ischaemia sooner with the potential for reduction in morbidity and mortality. © 2012 The Authors. Nursing in Critical Care �

Relationship between calcified carotid atheromas in digital panoramic radiographs and underlying systemic diseases in implant patients.

PubMed

Ngamsom, Supak; Arayasantiparb, Raweewan; Pornprasertsuk-Damrongsri, Suchaya; Sureephong, Boonchoo

2015-11-01

The aim of the present study was to evaluate the correlation between calcified carotid atheromas (CCA) detected on digital panoramic radiographs and underlying systemic diseases. Panoramic radiographs and underlying systemic diseases of retained mandibular denture implants in 265 patients (56 males, 209 females) aged over 50 years were retrospectively evaluated at the Dental Unit of Prasat Neurological Institute, Bangkok, Thailand. The mean age of the patients was 71 ± 7.1 years. The prevalence of CCA was 38.49%. The major underlying systemic diseases were hypertension, hyperlipidemia, diabetes mellitus, and cardiovascular diseases (CVD), respectively. No relationship was found among these four systemic diseases in detecting CCA on panoramic radiographs. Similar findings were also observed in patients with only one systemic disease versus in combination with other diseases. The presence of CCA on dental panoramic radiographs was not found to be related to the presence of underlying systemic diseases, including hypertension, hyperlipidemia, diabetes mellitus, and CVD. © 2014 Wiley Publishing Asia Pty Ltd.

31. Panoramic shot, Huber Breaker (left), Retail Coal Storage Bins ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

31. Panoramic shot, Huber Breaker (left), Retail Coal Storage Bins (center), Boney Elevator (right) Photographs taken by Joseph E.B. Elliot - Huber Coal Breaker, 101 South Main Street, Ashley, Luzerne County, PA

A new screening pathway for identifying asymptomatic patients using dental panoramic radiographs

NASA Astrophysics Data System (ADS)

Hayashi, Tatsuro; Matsumoto, Takuya; Sawagashira, Tsuyoshi; Tagami, Motoki; Katsumata, Akitoshi; Hayashi, Yoshinori; Muramatsu, Chisako; Zhou, Xiangrong; Iida, Yukihiro; Matsuoka, Masato; Katagi, Kiyoji; Fujita, Hiroshi

2012-03-01

To identify asymptomatic patients is the challenging task and the essential first step in diagnosis. Findings of dental panoramic radiographs include not only dental conditions but also radiographic signs that are suggestive of possible systemic diseases such as osteoporosis, arteriosclerosis, and maxillary sinusitis. Detection of such signs on panoramic radiographs has a potential to provide supplemental benefits for patients. However, it is not easy for general dental practitioners to pay careful attention to such signs. We addressed the development of a computer-aided detection (CAD) system that detects radiographic signs of pathology on panoramic images, and the design of the framework of new screening pathway by cooperation of dentists and our CAD system. The performance evaluation of our CAD system showed the sensitivity and specificity in the identification of osteoporotic patients were 92.6 % and 100 %, respectively, and those of the maxillary sinus abnormality were 89.6 % and 73.6 %, respectively. The detection rate of carotid artery calcifications that suggests the need for further medical evaluation was approximately 93.6 % with 4.4 false-positives per image. To validate the utility of the new screening pathway, preliminary clinical trials by using our CAD system were conducted. To date, 223 panoramic images were processed and 4 asymptomatic patients with suspected osteoporosis, 7 asymptomatic patients with suspected calcifications, and 40 asymptomatic patients with suspected maxillary sinusitis were detected in our initial trial. It was suggested that our new screening pathway could be useful to identify asymptomatic patients with systemic diseases.

High-resolution panoramic images with megapixel MWIR FPA

NASA Astrophysics Data System (ADS)

Leboucher, Vincent; Aubry, Gilles

2014-06-01

In the continuity of its current strategy, HGH maintains a deep effort in developing its most recent product family: the infrared (IR) panoramic 360-degree surveillance sensors. During the last two years, HGH optimized its prototype Middle Wave IR (MWIR) panoramic sensor IR Revolution 360 HD that gave birth to Spynel-S product. Various test campaigns proved its excellent image quality. Cyclope, the software associated with Spynel, benefitted from recent image processing improvements and new functionalities such as target geolocalization, long range sensor slue to cue and facilitated forensics analysis. In the frame of the PANORAMIR project sustained by the DGA (Délégation Générale de l'Armement), HGH designed a new extra large resolution sensor including a MWIR megapixel Focal Plane Array (FPA) detector (1280×1024 pixels). This new sensor is called Spynel-X. It provides outstanding resolution 360-degree images (with more than 100 Mpixels). The mechanical frame of Spynel (-S and -X) was designed with the collaboration of an industrial design agency. Spynel got the "Observeur du Design 2013" label.

Student Incivility in Radiography Education.

PubMed

Clark, Kevin R

2017-07-01

To examine student incivility in radiography classrooms by exploring the prevalence of uncivil behaviors along with the classroom management strategies educators use to manage and prevent classroom disruptions. A survey was designed to collect data on the severity and frequency of uncivil student behaviors, classroom management strategies used to address minor and major behavioral issues, and techniques to prevent student incivility. The participants were educators in radiography programs accredited by the Joint Review Committee on Education in Radiologic Technology. Findings indicated that severe uncivil student behaviors in radiography classrooms do not occur as often as behaviors classified as less severe. Radiography educators in this study used a variety of strategies and techniques to manage and prevent student incivility; however, radiography educators who received formal training in classroom management reported fewer incidents of student incivility than those who had not received formal training. The participants in this study took a proactive approach to addressing severe behavioral issues in the classroom. Many radiography educators transition from the clinical environment to the classroom setting with little to no formal training in classroom management. Radiography educators are encouraged to attend formal training sessions to learn how to manage the higher education classroom effectively. Student incivility is present in radiography classrooms. This study provides a foundation for future research on incivility. ©2017 American Society of Radiologic Technologists.

Evaluation of the radiation dose in the thyroid gland using different protective collars in panoramic imaging.

PubMed

Hafezi, Ladan; Arianezhad, S Marjan; Hosseini Pooya, Seyed Mahdi

2018-04-25

The value for the use of thyroid shield is one of the issues in radiation protection of patients in dental panoramic imaging. The objective of this research is to investigate the attenuation characteristics of some models of thyroid shielding in dental panoramic examinations. The effects of five different types of lead and lead-free (Pb-equivalent) shields on dose reduction of thyroid gland were investigated using implanted Thermoluminescence Dosemeters (TLDs) in head-neck parts of a Rando phantom. The results show that frontal lead and Pb-equivalent shields can reduce the thyroid dose around 50% and 19%, respectively. It can be concluded that the effective shielding area is an important parameter in thyroid gland dose reduction. Lead frontal collars with large effective shielding areas (>~300 cm 2 but not necessarily very large) are appropriate for an optimized thyroid gland dose reduction particularly for the critical patients in dental panoramic imaging. Regardless of the shape and thickness, using the Pb-equivalent shields is not justifiable in dental panoramic imaging.

Applications of Panoramic Images: from 720° Panorama to Interior 3d Models of Augmented Reality

NASA Astrophysics Data System (ADS)

Lee, I.-C.; Tsai, F.

2015-05-01

A series of panoramic images are usually used to generate a 720° panorama image. Although panoramic images are typically used for establishing tour guiding systems, in this research, we demonstrate the potential of using panoramic images acquired from multiple sites to create not only 720° panorama, but also three-dimensional (3D) point clouds and 3D indoor models. Since 3D modeling is one of the goals of this research, the location of the panoramic sites needed to be carefully planned in order to maintain a robust result for close-range photogrammetry. After the images are acquired, panoramic images are processed into 720° panoramas, and these panoramas which can be used directly as panorama guiding systems or other applications. In addition to these straightforward applications, interior orientation parameters can also be estimated while generating 720° panorama. These parameters are focal length, principle point, and lens radial distortion. The panoramic images can then be processed with closerange photogrammetry procedures to extract the exterior orientation parameters and generate 3D point clouds. In this research, VisaulSFM, a structure from motion software is used to estimate the exterior orientation, and CMVS toolkit is used to generate 3D point clouds. Next, the 3D point clouds are used as references to create building interior models. In this research, Trimble Sketchup was used to build the model, and the 3D point cloud was added to the determining of locations of building objects using plane finding procedure. In the texturing process, the panorama images are used as the data source for creating model textures. This 3D indoor model was used as an Augmented Reality model replacing a guide map or a floor plan commonly used in an on-line touring guide system. The 3D indoor model generating procedure has been utilized in two research projects: a cultural heritage site at Kinmen, and Taipei Main Station pedestrian zone guidance and navigation system. The

Sex Determination of Adult Human Maxillary Sinuses on Panoramic Radiographs

PubMed Central

Leao de Queiroz, Cristhiane; Terada, Andrea Sayuri Silveira Dias; Dezem, Thais Uenoyama; Gomes de Araújo, Lais; Galo, Rodrigo; Oliveira-Santos, Christiano

2016-01-01

Absract The purpose of this study was to evaluate dimensions of adult human maxillary sinuses on panoramic radiographs and their possible application on the sex determination for forensic purposes. The sample comprised 64 database panoramic radiographs from individuals aged 20 years or older (32 male and 32 female subjects), with complete permanent dentition (or absence of third molars). One examiner measured the width and height of the right and left maxillary sinuses using the software Image J 1.47v (National Institutes of Health, Bethesda, USA). Measurements were repeated to calculate intra-observer agreement. Chi-Square test, Kappa, ANOVA and T-Student were used for results analysis for p≤ 0.05. Intra-observer agreement with correlation Kappa ranged between 0.38 and 0.96. For female subjects, the mean height and width of the left maxillary sinus were 28.7856mm and 44.6178mm, respectively. And right maxillary sinus was 27.7163mm for height and 45.1850mm for width. Male subjects were found to have the mean height and width of the left maxillary sinus 30.9981mm and 48.7753mm, respectively. And right maxillary sinus was 30.7403mm for height and 48.5753mm for width. There was a statistically significant difference in the height and width of maxillary sinuses between males and females. It can be concluded that maxillary sinuses height and width on panoramic radiographs can be used to determine the gender of adult human subjects. PMID:27847394

Genotoxic effects of X-rays in buccal mucosal cells in children subjected to dental radiographs

PubMed Central

Preethi, Naveena; Chikkanarasaiah, Nagarathna; Bethur, Shakuntala S

2016-01-01

Objectives/Aims: Bitewing and digital dental panoramic radiographs have become important adjuvants for successful dental practice in pediatric dentistry. Both methods lead to genetic changes in the oral buccal epithelium that have not yet been satisfactorily explored. The aim of the present study was to evaluate the genotoxic effects induced by X-ray radiation from bitewing and panoramic dental radiography in exfoliated buccal epithelial cells of children, using the Buccal Micronucleus Cytome assay. Materials and Methods: Children (n=40) who met the inclusion criteria and provided signed informed consent were included in the study. Children were selected for undergoing bitewing radiographs (group 1; n=20) or digital dental panoramic radiographs (group 2; n=20). Exfoliated buccal mucosal cells were obtained by scraping the right/left buccal mucosa with a wooden spatula immediately before the X-ray exposure and 10±2 days after exposure. Results: The frequency of micronuclei increases significantly post exposure to both bitewing and digital dental panoramic radiography in children, but the frequency was higher in bitewing radiographs. Conclusion: It was concluded that the frequency of micronuclei increases post exposure to both bitewing and digital panoramic radiographs. Increased radiation exposure results in an increase in micronuclei frequency. PMID:29607062

An infrared modular panoramic imaging objective

NASA Astrophysics Data System (ADS)

Palmer, Troy A.; Alexay, Christopher C.

2004-08-01

We describe the optical and mechanical design of an athermal infrared objective lens with an afocal anamorphic adapter. The lens presented consists of two modules: an athermal 25mm F/2.3 mid-wave IR objective lens and an optional panoramic adapter. The adapter utilizes anamorphic lenses to create unique image control. The result of which enables an independent horizontal wide field of view, while preserving the original narrow vertical field. We have designed, fabricated and tested two such lenses. A summary of the assembly and testing process is also presented.

Mandibular incisive canal: cone beam computed tomography.

PubMed

Pires, Carlos A; Bissada, Nabil F; Becker, Jeffery J; Kanawati, Ali; Landers, Michael A

2012-03-01

Panoramic radiography is often used to analyze the anatomical structure of the teeth, jaws, and temporomandibular joints. Cone beam computed tomography (CBCT) imaging allows multiple axial slices of the image to be obtained through these anatomical structures. The aim of this study was to assess CBCT compared with panoramic radiography to verify the presence, location, and dimensions of the mandibular incisive canal. CBCT scan images and panoramic radiographs of 89 subjects were compared for the presence of the mandibular incisive canal, its location, size, and anterior-posterior length. The distance between the incisive canal and the buccal and lingual plate of the alveolar bone, and the distance from the canal to the inferior border of the mandible and the tooth apex were also measured. A paired t-test was used to calculate any significant difference between the two imaging techniques. Eighty-three percent of the CBCT scans showed the presence of the incisive canal, as did 11% of the panoramic radiographs. The range of the incisive canal diameter, as seen in the CBCT scans, was from 0.4 × 0.4 mm to 4.6 × 3.2 mm. The mean length of the canal was 7 ± 3.8 mm. The distance from the inferior border of the mandible to the canal was 10.2 ± 2.4 mm, and the mean distance to the buccal plate was 2.4 mm. The apex-canal distance (in dentate subjects) was 5.3 mm. The presence, location, and dimensions of the mandibular incisive canal are better determined by CBCT imaging than by panoramic radiography. © 2009 Wiley Periodicals, Inc.

60. PANORAMIC VIEW OF DOWNSTREAM FACE. No date, but believed ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

60. PANORAMIC VIEW OF DOWNSTREAM FACE. No date, but believed to be just subsequent to construction. Photograph by C.G. Duffey, Long Beach, California. (38' x 11' framed print). - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

Comparison of computed radiography and conventional radiography in detection of small volume pneumoperitoneum.

PubMed

Marolf, Angela; Blaik, Margaret; Ackerman, Norman; Watson, Elizabeth; Gibson, Nicole; Thompson, Margret

2008-01-01

The role of digital imaging is increasing as these systems are becoming more affordable and accessible. Advantages of computed radiography compared with conventional film/screen combinations include improved contrast resolution and postprocessing capabilities. Computed radiography's spatial resolution is inferior to conventional radiography; however, this limitation is considered clinically insignificant. This study prospectively compared digital imaging and conventional radiography in detecting small volume pneumoperitoneum. Twenty cadaver dogs (15-30 kg) were injected with 0.25, 0.25, and 0.5 ml for 1 ml total of air intra-abdominally, and radiographed sequentially using computed and conventional radiographic technologies. Three radiologists independently evaluated the images, and receiver operating curve (ROC) analysis compared the two imaging modalities. There was no statistical difference between computed and conventional radiography in detecting free abdominal air, but overall computed radiography was relatively more sensitive based on ROC analysis. Computed radiographic images consistently and significantly demonstrated a minimal amount of 0.5 ml of free air based on ROC analysis. However, no minimal air amount was consistently or significantly detected with conventional film. Readers were more likely to detect free air on lateral computed images than the other projections, with no significant increased sensitivity between film/screen projections. Further studies are indicated to determine the differences or lack thereof between various digital imaging systems and conventional film/screen systems.

Multidirectional Image Sensing for Microscopy Based on a Rotatable Robot.

PubMed

Shen, Yajing; Wan, Wenfeng; Zhang, Lijun; Yong, Li; Lu, Haojian; Ding, Weili

2015-12-15

Image sensing at a small scale is essentially important in many fields, including microsample observation, defect inspection, material characterization and so on. However, nowadays, multi-directional micro object imaging is still very challenging due to the limited field of view (FOV) of microscopes. This paper reports a novel approach for multi-directional image sensing in microscopes by developing a rotatable robot. First, a robot with endless rotation ability is designed and integrated with the microscope. Then, the micro object is aligned to the rotation axis of the robot automatically based on the proposed forward-backward alignment strategy. After that, multi-directional images of the sample can be obtained by rotating the robot within one revolution under the microscope. To demonstrate the versatility of this approach, we view various types of micro samples from multiple directions in both optical microscopy and scanning electron microscopy, and panoramic images of the samples are processed as well. The proposed method paves a new way for the microscopy image sensing, and we believe it could have significant impact in many fields, especially for sample detection, manipulation and characterization at a small scale.

Pre- and postoperative assessment of sinus grafting procedures using cone-beam computed tomography compared with panoramic radiographs.

PubMed

Baciut, Mihaela; Hedesiu, Mihaela; Bran, Simion; Jacobs, Reinhilde; Nackaerts, Olivia; Baciut, Grigore

2013-05-01

The present study evaluated the clinical validity of cone-beam computed tomography (CBCT) scans in comparison to panoramic radiographs regarding preoperative implant planning in combination with sinus grafting procedures. Preoperative assessment of the maxillary sinuses and implant planning using panoramic radiographs and CBCT scans was performed on 16 sinuses (13 patients) and comprised choice of treatment, timing of implant placement, sinus morphology, level of confidence, complication prediction and graft volume assessment. Six examiners were involved in the study. In the majority of cases there was a concordance between the treatment type based on either panoramic radiographs or CBCT. If any difference was found, this was due to an overestimation of bone quantity and quality on panoramic radiographs. The assessment of sinus morphology showed a significantly higher detection rate of sinus mucosal hypertrophy on CBCT. The most appealing result is a significant increase in surgical confidence and a significantly better prediction of complications when using CBCT. A preoperative planning based on CBCT seems to improve sinus diagnostics and surgical confidence. © 2012 John Wiley & Sons A/S.

Virtual environments from panoramic images

NASA Astrophysics Data System (ADS)

Chapman, David P.; Deacon, Andrew

1998-12-01

A number of recent projects have demonstrated the utility of Internet-enabled image databases for the documentation of complex, inaccessible and potentially hazardous environments typically encountered in the petrochemical and nuclear industries. Unfortunately machine vision and image processing techniques have not, to date, enabled the automatic extraction geometrical data from such images and thus 3D CAD modeling remains an expensive and laborious manual activity. Recent developments in panoramic image capture and presentation offer an alternative intermediate deliverable which, in turn, offers some of the benefits of a 3D model at a fraction of the cost. Panoramic image display tools such as Apple's QuickTime VR (QTVR) and Live Spaces RealVR provide compelling and accessible digital representations of the real world and justifiably claim to 'put the reality in Virtual Reality.' This paper will demonstrate how such technologies can be customized, extended and linked to facility management systems delivered over a corporate intra-net to enable end users to become familiar with remote sites and extract simple dimensional data. In addition strategies for the integration of such images with documents gathered from 2D or 3D CAD and Process and Instrumentation Diagrams (P&IDs) will be described as will techniques for precise 'As-Built' modeling using the calibrated images from which panoramas have been derived and the use of textures from these images to increase the realism of rendered scenes. A number of case studies relating to both nuclear and process engineering will demonstrate the extent to which such solution are scaleable in order to deal with the very large volumes of image data required to fully document the large, complex facilities typical of these industry sectors.

Visualization of oil behavior in a small 4-cycle engine with electrical motoring by neutron radiography

NASA Astrophysics Data System (ADS)

Nakamura, M.; Sugimoto, K.; Asano, H.; Murakawa, H.; Takenaka, N.; Mochiki, K.

2009-06-01

Neutron radiography is suitable for the visualization of liquid behavior in a metallic machine. Observation of oil behavior in a small 4-cycle engine on operating was carried out by using the neutron radiography facility at JRR-3 in JAEA. The engine was not fired but operated by an electrical motor. Movies were taken by a neutron image intensifier with a color CCD camera of 8-bit resolution, 30 frames/s and 640×480 pixels developed by Toshiba Corp. The engine was placed on a turn table and was rotated, so the movie could be taken from any angle. Numbers of revolution of the engine were changed from 260 to 1200 rpm. Visualized images of the mechanism and the oil behavior in the engine were obtained.

Localization and Mapping Using Only a Rotating FMCW Radar Sensor

PubMed Central

Vivet, Damien; Checchin, Paul; Chapuis, Roland

2013-01-01

Rotating radar sensors are perception systems rarely used in mobile robotics. This paper is concerned with the use of a mobile ground-based panoramic radar sensor which is able to deliver both distance and velocity of multiple targets in its surrounding. The consequence of using such a sensor in high speed robotics is the appearance of both geometric and Doppler velocity distortions in the collected data. These effects are, in the majority of studies, ignored or considered as noise and then corrected based on proprioceptive sensors or localization systems. Our purpose is to study and use data distortion and Doppler effect as sources of information in order to estimate the vehicle's displacement. The linear and angular velocities of the mobile robot are estimated by analyzing the distortion of the measurements provided by the panoramic Frequency Modulated Continuous Wave (FMCW) radar, called IMPALA. Without the use of any proprioceptive sensor, these estimates are then used to build the trajectory of the vehicle and the radar map of outdoor environments. In this paper, radar-only localization and mapping results are presented for a ground vehicle moving at high speed. PMID:23567523

Localization and mapping using only a rotating FMCW radar sensor.

PubMed

Vivet, Damien; Checchin, Paul; Chapuis, Roland

2013-04-08

Rotating radar sensors are perception systems rarely used in mobile robotics. This paper is concerned with the use of a mobile ground-based panoramic radar sensor which is able to deliver both distance and velocity of multiple targets in its surrounding. The consequence of using such a sensor in high speed robotics is the appearance of both geometric and Doppler velocity distortions in the collected data. These effects are, in the majority of studies, ignored or considered as noise and then corrected based on proprioceptive sensors or localization systems. Our purpose is to study and use data distortion and Doppler effect as sources of information in order to estimate the vehicle's displacement. The linear and angular velocities of the mobile robot are estimated by analyzing the distortion of the measurements provided by the panoramic Frequency Modulated Continuous Wave (FMCW) radar, called IMPALA. Without the use of any proprioceptive sensor, these estimates are then used to build the trajectory of the vehicle and the radar map of outdoor environments. In this paper, radar-only localization and mapping results are presented for a ground vehicle moving at high speed.

Dosimetry in Diagnostic Radiology: A Guide for Meeting JCAHO and ACR requirements and ICRP Recommendations

DTIC Science & Technology

1998-01-01

C-Arms and Digital Fluorscopy ....... ............................. 6 Image Intensifier III) Input Exposure Rates and Exposures...Setup for ESE Measurements in Conventional Radiography .................. 3 Figure 2: Setup tor IP ;R M easurem ents...exposure from dental procedures. An area of dental radiography which has not been well addressed is the dose received during panoramic or panalipse

Condylar guidance: correlation between protrusive interocclusal record and panoramic radiographic image: a pilot study.

PubMed

Tannamala, Pavan Kumar; Pulagam, Mahesh; Pottem, Srinivas R; Swapna, B

2012-04-01

The purpose of this study was to compare the sagittal condylar angles set in the Hanau articulator by use of a method of obtaining an intraoral protrusive record to those angles found using a panoramic radiographic image. Ten patients, free of signs and symptoms of temporomandibular disorder and with intact dentition were selected. The dental stone casts of the subjects were mounted on a Hanau articulator with a springbow and poly(vinyl siloxane) interocclusal records. For all patients, the protrusive records were obtained when the mandible moved forward by approximately 6 mm. All procedures for recording, mounting, and setting were done in the same session. The condylar guidance angles obtained were tabulated. A panoramic radiographic image of each patient was made with the Frankfurt horizontal plane parallel to the floor of the mouth. Tracings of the radiographic images were made. The horizontal reference line was marked by joining the orbitale and porion. The most superior and most inferior points of the curvatures were identified. These two lines were connected by a straight line representing the mean curvature line. Angles made by the intersection of the mean curvature line and the horizontal reference line were measured. The results were subjected to statistical analysis with a significance level of p < 0.05. The radiographic values were on average 4° greater than the values obtained by protrusive interocclusal record method. The mean condylar guidance angle between the right and left side by both the methods was not statistically significant. The comparison of mean condylar guidance angles between the right side of the protrusive record method and the right side of the panoramic radiographic method and the left side of the protrusive record method and the left side of the panoramic radiographic method (p= 0.071 and p= 0.057, respectively) were not statistically significant. Within the limitations of this study, it was concluded that the protrusive condylar

3. Panoramic view of Broad Street bridge in foreground and ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. Panoramic view of Broad Street bridge in foreground and a major portion of the historic bridge. As seem from the top of the American Electric Power building looking south. - Broad Street Bridge, Spanning Scioto River at U.S. Route 40 (Broad Street), Columbus, Franklin County, OH

Panoramic Measurement and Analysis of Strain Distribution in the Human ACL Using a Photoelastic Coating Method

NASA Astrophysics Data System (ADS)

Hirokawa, Shunji; Yamamoto, Kouji; Kawada, Takashi

Large and highly variable deformations of the ACL cannot be adequately quantified by one-dimensional and/or localized measurements. Since the complex anatomy of the ACL makes uniform loading of all fiber bundles almost impossible, strains on specific portions being tested are considerably altered during knee movement. To observe the ACL's entire surface, we propose a photoelastic coating method. A simulator jig was used to allow a natural motion of the knee whose medial and lateral femoral bone parts were removed in order to expose the ACL for observation. The simulator jig with the knee was mounted on a universal stand which allows tilt and swivel rotations, so that the exposed ACL might be viewed from any direction. Measurements were performed on the strain distributions over the ACL at various knee angles. The panoramic images of the photoelastic fringe patterns yielded significant results. Special attention was paid for insight into the relation between strain distribution and the directions of fiber run.

Dental Students' Interpretations of Digital Panoramic Radiographs on Completely Edentate Patients.

PubMed

Kratz, Richard J; Nguyen, Caroline T; Walton, Joanne N; MacDonald, David

2018-03-01

The ability of dental students to interpret digital panoramic radiographs (PANs) of edentulous patients has not been documented. The aim of this retrospective study was to compare the ability of second-year (D2) dental students with that of third- and fourth-year (D3-D4) dental students to interpret and identify positional errors in digital PANs obtained from patients with complete edentulism. A total of 169 digital PANs from edentulous patients were assessed by D2 (n=84) and D3-D4 (n=85) dental students at one Canadian dental school. The correctness of the students' interpretations was determined by comparison to a gold standard established by assessments of the same PANs by two experts (a graduate student in prosthodontics and an oral and maxillofacial radiologist). Data collected were from September 1, 2006, when digital radiography was implemented at the university, to December 31, 2012. Nearly all (95%) of the PANs were acceptable diagnostically despite a high proportion (92%) of positional errors detected. A total of 301 positional errors were identified in the sample. The D2 students identified significantly more (p=0.002) positional errors than the D3-D4 students. There was no significant difference (p=0.059) in the distribution of radiographic interpretation errors between the two student groups when compared to the gold standard. Overall, the category of extragnathic findings had the highest number of false negatives (43) reported. In this study, dental students interpreted digital PANs of edentulous patients satisfactorily, but they were more adept at identifying radiographic findings compared to positional errors. Students should be reminded to examine the entire radiograph thoroughly to ensure extragnathic findings are not missed and to recognize and report patient positional errors.

Problems associated with digital luminescence radiography in the neonate and young infant. Problems with digital radiography.

PubMed

Arthur, R J; Pease, J N

1992-01-01

An evaluation of the Siemens Digiscan has been undertaken to determine whether digital luminescence radiography (DLR) could replace conventional radiography in the examination of the neonate and young infant. Whilst the overall image quality of the digital radiograph was consistently higher than for conventional radiography the difference was less marked than we had expected. Furthermore, the potential for reduction in radiation dose by reducing the repeat rate due to incorrect exposure was limited. The potential advantages of DLR have been critically examined in relationship to neonatal radiography and a number of problems encountered during the evaluation have been highlighted.

Panoramic optical-servoing for industrial inspection and repair

NASA Astrophysics Data System (ADS)

Sallinger, Christian; O'Leary, Paul; Retschnig, Alexander; Kammerhofer, Martin

2004-05-01

Recently specialized robots were introduced to perform the task of inspection and repair in large cylindrical structures such as ladles, melting furnaces and converters. This paper reports on the image processing system and optical servoing for one such a robot. A panoramic image of the vessels inner surface is produced by performing a coordinated robot motion and image acquisition. The level of projective distortion is minimized by acquiring a high density of images. Normalized phase correlation calculated via the 2D Fourier transform is used to calculate the shift between the single images. The narrow strips from the dense image map are then stitched together to build the panorama. The mapping between the panoramic image and the positioning of the robot is established during the stitching of the images. This enables optical feedback. The robots operator can locate a defect on the surface by selecting the area of the image. Calculation of the forward and inverse kinematics enable the robot to automatically move to the location on the surface requiring repair. Experimental results using a standard 6R industrial robot have shown the full functionality of the system concept. Finally, were test measurements carried out successfully, in a ladle at a temperature of 1100° C.

The Image Gently pediatric digital radiography safety checklist: tools for improving pediatric radiography.

PubMed

John, Susan D; Moore, Quentin T; Herrmann, Tracy; Don, Steven; Powers, Kevin; Smith, Susan N; Morrison, Greg; Charkot, Ellen; Mills, Thalia T; Rutz, Lois; Goske, Marilyn J

2013-10-01

Transition from film-screen to digital radiography requires changes in radiographic technique and workflow processes to ensure that the minimum radiation exposure is used while maintaining diagnostic image quality. Checklists have been demonstrated to be useful tools for decreasing errors and improving safety in several areas, including commercial aviation and surgical procedures. The Image Gently campaign, through a competitive grant from the FDA, developed a checklist for technologists to use during the performance of digital radiography in pediatric patients. The checklist outlines the critical steps in digital radiography workflow, with an emphasis on steps that affect radiation exposure and image quality. The checklist and its accompanying implementation manual and practice quality improvement project are open source and downloadable at www.imagegently.org. The authors describe the process of developing and testing the checklist and offer suggestions for using the checklist to minimize radiation exposure to children during radiography. Copyright © 2013 American College of Radiology. All rights reserved.

[High-contrast resolution of film-screen systems in oral and maxillofacial radiology].

PubMed

Kaeppler, G; Reinert, S

2007-11-01

The aim was to determine differences in high-contrast resolution of film-screen systems used in dental panoramic and cephalometric radiography by calculating the modulation transfer function (MTF). The radiographs used to determine the MTF should be taken by the same x-ray units as those used for patient radiographs. The MTF was determined using a lead grid and according to DIN 6867-2 for 11 film-screen systems (speed 250, speed class 200 and 400) used in dental radiographic diagnostics. The optical density was measured using a microdensitometer developed by PTB. With 10% of the modulation transfer factor, newly developed film-screen systems (speed class 200 and 400) demonstrated a resolution of 4.9 to 6 line pairs per mm (panoramic radiography). In cephalometric radiography a film-screen system (speed class 400 and green-sensitive film) had a resolution of 4.2 line pairs per mm and surpassed two film-screen systems (speed class 400, resolution of 3 line pairs per mm, blue-sensitive films). The relevance of this study is underlined by the diagnostic reference doses defined in the German X-ray Ordinance (RöV) which are also intended for dentistry. Film-screen systems (speed 250, speed class 200) previously used in dental panoramic and cephalometric radiography can be replaced by newly developed film-screen systems (speed class 400). In dental radiography dose reductions are possible with film-screen systems (speed class 400) without impairing diagnostic accuracy. The introduction of newly developed film-screen systems (speed class 400) requires lower milliampere-seconds and therefore an adjustment of the x-ray units to lower milliampere settings.

Evaluation and nonsurgical management of rotator cuff calcific tendinopathy.

PubMed

Greis, Ari C; Derrington, Stephen M; McAuliffe, Matthew

2015-04-01

Rotator cuff calcific tendinopathy is a common finding that accounts for about 7% of patients with shoulder pain. There are numerous theories on the pathogenesis of rotator cuff calcific tendinopathy. The diagnosis is confirmed with radiography, MRI or ultrasound. There are numerous conservative treatment options available and most patients can be managed successfully without surgical intervention. Nonsteroidal anti-inflammatory drugs and multiple modalities are often used to manage pain and inflammation; physical therapy can help improve scapular mechanics and decrease dynamic impingement; ultrasound-guided needle aspiration and lavage techniques can provide long-term improvement in pain and function in these patients. Copyright © 2015 Elsevier Inc. All rights reserved.

Pit above the lesser tuberosity in axial view radiography.

PubMed

Cho, Jae-Ho; Han, Kyeong-Jin; Lee, Doo-Hyung; Chung, Nam-Su; Park, Do Young

2015-02-01

This study examined the relationship between the presence of a pit above the lesser tuberosity on axial view radiographs and rotator cuff tears and compared the demographic data between groups according to the presence of a pit above the lesser tuberosity. The hypothesis of this study was that the radiographic finding of a pit above the lesser tuberosity is related to rotator cuff tears. For 112 patients with a symptomatic rotator cuff tear, plain radiographs of the symptomatic shoulder (tear side radiographs) and plain radiographs of the asymptomatic contralateral shoulder (no-tear side radiographs) were assessed. Seventeen radiological findings, including a pit above the lesser tuberosity, osteophytes, subchondral cysts, and sclerosis, were recorded by one blinded observer. Demographic data such as age, duration of symptoms, sex, arm dominance, smoking history, trauma history, American Shoulder and Elbow Surgeons score, Constant score, and involved tendon were collected. A pit above the lesser tuberosity was noted on tear side radiographs of 40 patients (35.7 %) and on the no-tear side radiographs of 27 patients (24.1 %), representing a significant difference (P = 0.040). A pit associated with a rotator cuff tear was observed more often in the dominant arm (P = 0.040) and more often in patients with less previous trauma (P = 0.024). A pit above the lesser tuberosity on axial view radiography was associated with a rotator cuff tear and occurred more often in the dominant arm of patients who had no trauma history. Prognostic study, Level III.

Image Acquisition and Quality in Digital Radiography.

PubMed

Alexander, Shannon

2016-09-01

Medical imaging has undergone dramatic changes and technological breakthroughs since the introduction of digital radiography. This article presents information on the development of digital radiography and types of digital radiography systems. Aspects of image quality and radiation exposure control are highlighted as well. In addition, the article includes related workplace changes and medicolegal considerations in the digital radiography environment. ©2016 American Society of Radiologic Technologists.

RenderView: physics-based multi- and hyperspectral rendering using measured background panoramics

NASA Astrophysics Data System (ADS)

Talcott, Denise M.; Brown, Wade W.; Thomas, David J.

2003-09-01

As part of the survivability engineering process it is necessary to accurately model and visualize the vehicle signatures in multi- or hyperspectral bands of interest. The signature at a given wavelength is a function of the surface optical properties, reflection of the background and, in the thermal region, the emission of thermal radiation. Currently, it is difficult to obtain and utilize background models that are of sufficient fidelity when compared with the vehicle models. In addition, the background models create an additional layer of uncertainty in estimating the vehicles signature. Therefore, to meet exacting rendering requirements we have developed RenderView, which incorporates the full bidirectional reflectance distribution function (BRDF). Instead of using a modeled background we have incorporated a measured calibrated background panoramic image to provide the high fidelity background interaction. Uncertainty in the background signature is reduced to the error in the measurement which is considerably smaller than the uncertainty inherent in a modeled background. RenderView utilizes a number of different descriptions of the BRDF, including the Sandford-Robertson. In addition, it provides complete conservation of energy with off axis sampling. A description of RenderView will be presented along with a methodology developed for collecting background panoramics. Examples of the RenderView output and the background panoramics will be presented along with our approach to handling the solar irradiance problem.

An investigation into dental digital radiography in dental practices in West Kent following the introduction of the 2006 NHS General Dental Services contract.

PubMed

Mauthe, Peter W; Eaton, Kenneth A

2011-04-01

The primary aims of the study were to investigate the use of digital radiography within primary dental care practices in the West Kent Primary Care Trust (PCT) area and general dental practitioners' (GDPs) self-reported change in radiographic prescribing patterns following the introduction of the nGDS contract in 2006. Data were gathered via a piloted, self-completed questionnaire, and circulated to all GDPs listed on the National Health Service (NHS) Choices website as practising in the West Kent PCT area. There were three mailings and follow-up telephone calls. The resulting data were entered into a statistical software database and, where relevant, statistically tested, using the chi-square test and Pearson correlation coefficient. Of 223 GDPs, 168 (75%) responded. There were 163 usable questionnaires. The respondents represented 85% of the general dental practices in West Kent. Eighty (49%) respondents were using digital intra-oral radiography. Of those who used digital radiography, 44 (55%) reported that they used phosphor plate systems and 36 (45%) that they used direct digital sensors. Eighty-three (51%) had a panoramic machine in their practice, 46 of whom (55%) were using digital systems; of these, 32 (67%) were using a direct digital system. Seventy-one GDPs reported that they worked exclusively or mainly in private practice. Forty (56%) of these 'mainly private' GDPs reported that they used digital radiographic systems, whereas only 40 (44%) of the 89 'mainly NHS' GDPs reported using digital radio-graphic systems. On average, mainly private GDPs made the transition to a digital radiographic system six months before mainly NHS GDPs. Of those who provided NHS dentistry before and after April 2006, only 18 (14%) reported taking fewer radiographs and seven (6%) taking more. In February 2010, of the West Kent GDPs who responded to the questionnaire, just under 50% used digital radio graphy. Mainly private GDPs were more likely to use digital radiography than

Clinical feline dental radiography.

PubMed

Lemmons, Matthew

2013-05-01

Dental radiography is a necessary diagnostic modality in small animal practice. It is not possible to accurately assess and diagnose tooth resorption, periodontal disease, endodontic disease, neoplasia and injury without it. Dental radiography is also necessary for treatment and assessment of the patient postoperatively. Copyright © 2013 Elsevier Inc. All rights reserved.

Radiography of the Paranasal Sinuses

MedlinePlus

... your back or over your lap. This head. Radiography of the paranasal sinuses apron will protect your ... face, especially when lowering his or her head. Radiography of sitting and others while you are standing. ...

The Panoramic Camera (Pancam) Investigation on the NASA 2003 Mars Exploration Rover Mission

NASA Technical Reports Server (NTRS)

Bell, J. F., III; Squyres, S. W.; Herkenhoff, K. E.; Maki, J.; Schwochert, M.; Dingizian, A.; Brown, D.; Morris, R. V.; Arneson, H. M.; Johnson, M. J.

2003-01-01

The Panoramic Camera System (Pancam) is part of the Athena science payload to be launched to Mars in 2003 on NASA's twin Mars Exploration Rover (MER) missions. The Pancam imaging system on each rover consists of two major components: a pair of digital CCD cameras, and the Pancam Mast Assembly (PMA), which provides the azimuth and elevation actuation for the cameras as well as a 1.5 meter high vantage point from which to image. Pancam is a multispectral, stereoscopic, panoramic imaging system, with a field of regard provided by the PMA that extends across 360 of azimuth and from zenith to nadir, providing a complete view of the scene around the rover.

Dental radiography in New Zealand: digital versus film.

PubMed

Ting, N A; Broadbent, J M; Duncan, W J

2013-09-01

Digital x-ray systems offer advantages over conventional film systems, yet many dentists have not adopted digital technology. To assess New Zealand dental practitioners' use of--and preferences for--dental radiography systems. Cross-sectional survey. General and specialist dental practice. Postal questionnaire survey of a sample of 770 dentists (520 randomly selected general dental practitioners and all 250 specialists) listed in the 2012 NZ Dental Council Register. Type of radiography systems used by dentists. Dentists' experiences and opinions of conventional film and digital radiography. The participation rate was 55.2%. Digital radiography systems were used by 58.0% of participating dentists, most commonly among those aged 31-40 years. Users of digital radiography tended to report greater satisfaction with their radiography systems than users conventional films. Two-thirds of film users were interested in switching to digital radiography in the near future. Reasons given by conventional film users for not using digital radiography included cost, difficulty in integrating with other software systems, concern about potential technical errors, and the size and nature of the intra-oral sensors. Many dental practitioners have still not adopted digital radiography, yet its users are more satisfied with their radiography systems than are conventional film users. The latter may find changing to a digital system to be satisfying and rewarding.

Panoramic-image-based rendering solutions for visualizing remote locations via the web

NASA Astrophysics Data System (ADS)

Obeysekare, Upul R.; Egts, David; Bethmann, John

2000-05-01

With advances in panoramic image-based rendering techniques and the rapid expansion of web advertising, new techniques are emerging for visualizing remote locations on the WWW. Success of these techniques depends on how easy and inexpensive it is to develop a new type of web content that provides pseudo 3D visualization at home, 24-hours a day. Furthermore, the acceptance of this new visualization medium depends on the effectiveness of the familiarization tools by a segment of the population that was never exposed to this type of visualization. This paper addresses various hardware and software solutions available to collect, produce, and view panoramic content. While cost and effectiveness of building the content is being addressed using a few commercial hardware solutions, effectiveness of familiarization tools is evaluated using a few sample data sets.

Panoramic, large-screen, 3-D flight display system design

NASA Technical Reports Server (NTRS)

Franklin, Henry; Larson, Brent; Johnson, Michael; Droessler, Justin; Reinhart, William F.

1995-01-01

The report documents and summarizes the results of the required evaluations specified in the SOW and the design specifications for the selected display system hardware. Also included are the proposed development plan and schedule as well as the estimated rough order of magnitude (ROM) cost to design, fabricate, and demonstrate a flyable prototype research flight display system. The thrust of the effort was development of a complete understanding of the user/system requirements for a panoramic, collimated, 3-D flyable avionic display system and the translation of the requirements into an acceptable system design for fabrication and demonstration of a prototype display in the early 1997 time frame. Eleven display system design concepts were presented to NASA LaRC during the program, one of which was down-selected to a preferred display system concept. A set of preliminary display requirements was formulated. The state of the art in image source technology, 3-D methods, collimation methods, and interaction methods for a panoramic, 3-D flight display system were reviewed in depth and evaluated. Display technology improvements and risk reductions associated with maturity of the technologies for the preferred display system design concept were identified.

PANORAMIC VIEW OF SHIPYARD NO. 3, LOOKING SOUTH. FROM LEFT ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

PANORAMIC VIEW OF SHIPYARD NO. 3, LOOKING SOUTH. FROM LEFT TO CENTER ARE THE FORGE SHOP, MACHINE SHOP, GENERAL WAREHOUSE, AND RIGGERS LOFT/PAINT SHOP/SHEET METAL SHOP. FROM CENTER TO RIGHT ARE THE FIVE BASINS - Rosie the Riveter National Historical Park, Richmond Shipyard No. 3, Point Potrero, Richmond, Contra Costa County, CA

9. PANORAMIC VIEW WEST, FERNOW EXPERIMENTAL FOREST RESIDENCE, CHEAT DISTRICT ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. PANORAMIC VIEW WEST, FERNOW EXPERIMENTAL FOREST RESIDENCE, CHEAT DISTRICT RANGER RESIDENCE AND GARAGE, IMPLEMENT BUILDING, SEED EXTRACTOR BUILDING, CONE DRYING SHED, PUMP HOUSE, OIL HOUSE, CHEAT DISTRICT RANGER OFFICE, WASH HOUSE, AND NURSERY MANAGER'S RESIDENCE. PLANTING BEDS IN BACKGROUND. - Parsons Nursery, South side of U.S. Route 219, Parsons, Tucker County, WV

From Panoramic Photos to a Low-Cost Photogrammetric Workflow for Cultural Heritage 3d Documentation

NASA Astrophysics Data System (ADS)

D'Annibale, E.; Tassetti, A. N.; Malinverni, E. S.

2013-07-01

The research aims to optimize a workflow of architecture documentation: starting from panoramic photos, tackling available instruments and technologies to propose an integrated, quick and low-cost solution of Virtual Architecture. The broader research background shows how to use spherical panoramic images for the architectural metric survey. The input data (oriented panoramic photos), the level of reliability and Image-based Modeling methods constitute an integrated and flexible 3D reconstruction approach: from the professional survey of cultural heritage to its communication in virtual museum. The proposed work results from the integration and implementation of different techniques (Multi-Image Spherical Photogrammetry, Structure from Motion, Imagebased Modeling) with the aim to achieve high metric accuracy and photorealistic performance. Different documentation chances are possible within the proposed workflow: from the virtual navigation of spherical panoramas to complex solutions of simulation and virtual reconstruction. VR tools make for the integration of different technologies and the development of new solutions for virtual navigation. Image-based Modeling techniques allow 3D model reconstruction with photo realistic and high-resolution texture. High resolution of panoramic photo and algorithms of panorama orientation and photogrammetric restitution vouch high accuracy and high-resolution texture. Automated techniques and their following integration are subject of this research. Data, advisably processed and integrated, provide different levels of analysis and virtual reconstruction joining the photogrammetric accuracy to the photorealistic performance of the shaped surfaces. Lastly, a new solution of virtual navigation is tested. Inside the same environment, it proposes the chance to interact with high resolution oriented spherical panorama and 3D reconstructed model at once.

Prevalence of Dental Anomalies in Odisha Population: A Panoramic Radiographic Study.

PubMed

Goutham, Balasubramanya; Bhuyan, Lipsa; Chinnannavar, Sangamesh N; Kundu, Madhurima; Jha, Kunal; Behura, Shyam S

2017-07-01

The aim of this study was to evaluate the prevalence of dental anomalies (DAs) in Odisha population using panoramic radiographs. In this study, 1,080 panoramic radiographs were evaluated for DAs. Dental records were reviewed for diagnostic confirmation. Anomalies related to the shape, size, position of teeth, and number of roots (supernumerary roots) were evaluated. The study results showed the prevalence of DAs to be 35.27%. The most prevalent was dilaceration, which was seen in 46.71% cases followed by peg laterals in 20.99%. Dental anomalies were present in more than one-third of the study group, which was mostly related to shape of the teeth. Early diagnosis of these DAs helps in avoiding complications. Identification of DAs requires proper examination and thereby subsequent correct diagnosis. These anomalies can pose complications in normal functioning of orofacial complex. The knowledge of the prevalence of such anomalies aids dental practitioners for a proper treatment plan.

A Neutron Radiography System for Field Use

DTIC Science & Technology

1989-06-01

provoked a major renewal of interest in neutron radiography because it promises to bring neutron radiography to the workplace , a convenience provided...II I~F I C II i IiH i ii MTL TR 89-52 I-AD A NEUTRON RADIOGRAPHY SYSTEM N FOR FIELD USE e~m JOHN J. ANTAL and ALFRED S. MAROTTA, and LOUIS J. FARESE...COVERED A NEUTRON RADIOGRAPHY SYSTEM FOR FIELD USE Final Report 6. PERFORMING OR1. REPORT NUMBER 7. AUTHOR(s) S. CONTRACT OR GRANT NUMBER(s) John J

Mars Cameras Make Panoramic Photography a Snap

NASA Technical Reports Server (NTRS)

2008-01-01

If you wish to explore a Martian landscape without leaving your armchair, a few simple clicks around the NASA Web site will lead you to panoramic photographs taken from the Mars Exploration Rovers, Spirit and Opportunity. Many of the technologies that enable this spectacular Mars photography have also inspired advancements in photography here on Earth, including the panoramic camera (Pancam) and its housing assembly, designed by the Jet Propulsion Laboratory and Cornell University for the Mars missions. Mounted atop each rover, the Pancam mast assembly (PMA) can tilt a full 180 degrees and swivel 360 degrees, allowing for a complete, highly detailed view of the Martian landscape. The rover Pancams take small, 1 megapixel (1 million pixel) digital photographs, which are stitched together into large panoramas that sometimes measure 4 by 24 megapixels. The Pancam software performs some image correction and stitching after the photographs are transmitted back to Earth. Different lens filters and a spectrometer also assist scientists in their analyses of infrared radiation from the objects in the photographs. These photographs from Mars spurred developers to begin thinking in terms of larger and higher quality images: super-sized digital pictures, or gigapixels, which are images composed of 1 billion or more pixels. Gigapixel images are more than 200 times the size captured by today s standard 4 megapixel digital camera. Although originally created for the Mars missions, the detail provided by these large photographs allows for many purposes, not all of which are limited to extraterrestrial photography.

Is there a relation between local bone quality as assessed on panoramic radiographs and alveolar bone level?

PubMed

Nackaerts, Olivia; Gijbels, Frieda; Sanna, Anna-Maria; Jacobs, Reinhilde

2008-03-01

The aim was to explore the relation between radiographic bone quality on panoramic radiographs and relative alveolar bone level. Digital panoramic radiographs of 94 female patients were analysed (mean age, 44.5; range, 35-74). Radiographic density of the alveolar bone in the premolar region was determined using Agfa Musica software. Alveolar bone level and bone quality index (BQI) were also assessed. Relationships between bone density and BQI on one hand and the relative loss of alveolar bone level on the other were assessed. Mandibular bone density and loss of alveolar bone level were weakly but significantly negatively correlated for the lower premolar area (r = -.27). The BQI did not show a statistically significant relation to alveolar bone level. Radiographic mandibular bone density on panoramic radiographs shows a weak but significant relation to alveolar bone level, with more periodontal breakdown for less dense alveolar bone.

Artefacts found in computed radiography.

PubMed

Cesar, L J; Schueler, B A; Zink, F E; Daly, T R; Taubel, J P; Jorgenson, L L

2001-02-01

Artefacts on radiographic images are distracting and may compromise accurate diagnosis. Although most artefacts that occur in conventional radiography have become familiar, computed radiography (CR) systems produce artefacts that differ from those found in conventional radiography. We have encountered a variety of artefacts in CR images that were produced from four different models plate reader. These artefacts have been identified and traced to the imaging plate, plate reader, image processing software or laser printer or to operator error. Understanding the potential sources of CR artefacts will aid in identifying and resolving problems quickly and help prevent future occurrences.

Using athletic training clinical education standards in radiography.

PubMed

Giordano, Shelley; Harris, Katherine

2012-01-01

The selection of clinical education sites for radiography students is based on availability, access to radiographic examinations, and appropriate student-to-technologist ratio. Radiography program directors are not required to evaluate sites based on their educational validity (eg, the clinical instructor's knowledge of basic teaching and learning principles, how well the site communicates with the program, or the clinical instructor's involvement in professional organizations). The purpose of this study was to determine if a set of 12 clinical education standards used in athletic training would be applicable and beneficial to radiography program directors when selecting clinical sites for students. A survey concerning the applicability of the athletic training standards to radiography site selection was completed by 270 directors of radiography programs accredited by the Joint Review Committee on Education in Radiologic Technology. The survey results indicated the athletic training clinical education standards were considered applicable to the selection of clinical sites for radiography students and would be beneficial to radiography program directors when selecting sites.

Design and implementation of three-dimension texture mapping algorithm for panoramic system based on smart platform

NASA Astrophysics Data System (ADS)

Liu, Zhi; Zhou, Baotong; Zhang, Changnian

2017-03-01

Vehicle-mounted panoramic system is important safety assistant equipment for driving. However, traditional systems only render fixed top-down perspective view of limited view field, which may have potential safety hazard. In this paper, a texture mapping algorithm for 3D vehicle-mounted panoramic system is introduced, and an implementation of the algorithm utilizing OpenGL ES library based on Android smart platform is presented. Initial experiment results show that the proposed algorithm can render a good 3D panorama, and has the ability to change view point freely.

8. SECOND IMAGE OF THE PANORAMIC SERIES LOOKING WEST FROM ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. SECOND IMAGE OF THE PANORAMIC SERIES LOOKING WEST FROM THE UPHILL SIDE OF THE MILL. THE ORE RECEIVING HOUSE AND THE ORE DELIVERY TRESTLE IS IMAGE RIGHT, THE MILL BUILDING AND ANCILLARY STRUCTURE ARE IMAGE CENTER AND THE TOWN OF BODIE IS IMAGE BACKGROUND RIGHT. - Standard Gold Mill, East of Bodie Creek, Northeast of Bodie, Bodie, Mono County, CA

WE-G-209-01: Digital Radiography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schueler, B.

Digital radiography, CT, PET, and MR are complicated imaging modalities which are composed of many hardware and software components. These components work together in a highly coordinated chain of events with the intent to produce high quality images. Acquisition, processing and reconstruction of data must occur in a precise way for optimum image quality to be achieved. Any error or unexpected event in the entire process can produce unwanted pixel intensities in the final images which may contribute to visible image artifacts. The diagnostic imaging physicist is uniquely qualified to investigate and contribute to resolution of image artifacts. This coursemore » will teach the participant to identify common artifacts found clinically in digital radiography, CT, PET, and MR, to determine the causes of artifacts, and to make recommendations for how to resolve artifacts. Learning Objectives: Identify common artifacts found clinically in digital radiography, CT, PET and MR. Determine causes of various clinical artifacts from digital radiography, CT, PET and MR. Describe how to resolve various clinical artifacts from digital radiography, CT, PET and MR.« less

Panoramic Okavango Swamp, Botswana and Fires in Angola, Africa

NASA Image and Video Library

1991-08-11

In this panoramic view of the Okavango Swamp, Botswana, (19.0S, 22.0E), the Okavango River, seen in sunglint, flows into a topographic trough to form an inland delta. Water, trapped in the meandering delta distributaries is evaporated or transpired by vegetation. In Angola to the north, the many fires of the seasonal burning of savannah vegetation for land clearing, in preparation for agriculture, has filled the atmosphere with haze and smoke.

Panoramic 3d Vision on the ExoMars Rover

NASA Astrophysics Data System (ADS)

Paar, G.; Griffiths, A. D.; Barnes, D. P.; Coates, A. J.; Jaumann, R.; Oberst, J.; Gao, Y.; Ellery, A.; Li, R.

The Pasteur payload on the ESA ExoMars Rover 2011/2013 is designed to search for evidence of extant or extinct life either on or up to ˜2 m below the surface of Mars. The rover will be equipped by a panoramic imaging system to be developed by a UK, German, Austrian, Swiss, Italian and French team for visual characterization of the rover's surroundings and (in conjunction with an infrared imaging spectrometer) remote detection of potential sample sites. The Panoramic Camera system consists of a wide angle multispectral stereo pair with 65° field-of-view (WAC; 1.1 mrad/pixel) and a high resolution monoscopic camera (HRC; current design having 59.7 µrad/pixel with 3.5° field-of-view) . Its scientific goals and operational requirements can be summarized as follows: • Determination of objects to be investigated in situ by other instruments for operations planning • Backup and Support for the rover visual navigation system (path planning, determination of subsequent rover positions and orientation/tilt within the 3d environment), and localization of the landing site (by stellar navigation or by combination of orbiter and ground panoramic images) • Geological characterization (using narrow band geology filters) and cartography of the local environments (local Digital Terrain Model or DTM). • Study of atmospheric properties and variable phenomena near the Martian surface (e.g. aerosol opacity, water vapour column density, clouds, dust devils, meteors, surface frosts,) 1 • Geodetic studies (observations of Sun, bright stars, Phobos/Deimos). The performance of 3d data processing is a key element of mission planning and scientific data analysis. The 3d Vision Team within the Panoramic Camera development Consortium reports on the current status of development, consisting of the following items: • Hardware Layout & Engineering: The geometric setup of the system (location on the mast & viewing angles, mutual mounting between WAC and HRC) needs to be optimized w

Industrial Radiography | Radiation Protection | US EPA

EPA Pesticide Factsheets

2017-08-07

Manufacturers use a method called industrial radiography to check for cracks or flaws in materials. Radiation is used in industrial radiography to show problems not visible from the outside without damaging the material.

Particle Beam Radiography

NASA Astrophysics Data System (ADS)

Peach, Ken; Ekdahl, Carl

2014-02-01

Particle beam radiography, which uses a variety of particle probes (neutrons, protons, electrons, gammas and potentially other particles) to study the structure of materials and objects noninvasively, is reviewed, largely from an accelerator perspective, although the use of cosmic rays (mainly muons but potentially also high-energy neutrinos) is briefly reviewed. Tomography is a form of radiography which uses multiple views to reconstruct a three-dimensional density map of an object. There is a very wide range of applications of radiography and tomography, from medicine to engineering and security, and advances in instrumentation, specifically the development of electronic detectors, allow rapid analysis of the resultant radiographs. Flash radiography is a diagnostic technique for large high-explosive-driven hydrodynamic experiments that is used at many laboratories. The bremsstrahlung radiation pulse from an intense relativistic electron beam incident onto a high-Z target is the source of these radiographs. The challenge is to provide radiation sources intense enough to penetrate hundreds of g/cm2 of material, in pulses short enough to stop the motion of high-speed hydrodynamic shocks, and with source spots small enough to resolve fine details. The challenge has been met with a wide variety of accelerator technologies, including pulsed-power-driven diodes, air-core pulsed betatrons and high-current linear induction accelerators. Accelerator technology has also evolved to accommodate the experimenters' continuing quest for multiple images in time and space. Linear induction accelerators have had a major role in these advances, especially in providing multiple-time radiographs of the largest hydrodynamic experiments.

Reduction of radiation dose and imaging costs in scoliosis radiography. Application of large-screen image intensifier photofluorography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Manninen, H.; Kiekara, O.; Soimakallio, S.

1988-04-01

Photofluorography using a large-field image intensifier (Siemens Optilux 57) was applied to scoliosis radiography and compared with a full-size rare-earth screen/film technique. When scoliosis radiography (PA-projection) was performed on 25 adolescent patients, the photofluorographs were found to be of comparable diagnostic quality with full-size films. A close correspondence between the imaging techniques was found in the Cobb angle measurements as well as in the grading of rotation with the pedicle method. The use of photofluorography results in a radiation dose reduction of about one-half and considerable savings in direct imaging costs and archive space. In our opinion the method ismore » particularly well-suited for follow-up and screening evaluation of scoliosis, but in tall patients the image field size of 40 x 40 cm restricts its usefulness as initial examination.« less

Effect of bone chip orientation on quantitative estimates of changes in bone mass using digital subtraction radiography.

PubMed

Mol, André; Dunn, Stanley M

2003-06-01

To assess the effect of the orientation of arbitrarily shaped bone chips on the correlation between radiographic estimates of bone loss and true mineral loss using digital subtraction radiography. Twenty arbitrarily shaped bone chips (dry weight 1-10 mg) were placed individually on the superior lingual aspect of the interdental alveolar bone of a dry dentate hemi-mandible. After acquiring the first baseline image, each chip was rotated 90 degrees and a second radiograph was captured. Follow-up images were created without the bone chips and after rotating the mandible 0, 1, 2, 4, and 6 degrees around a vertical axis. Aluminum step tablet intensities were used to normalize image intensities for each image pair. Follow-up images were registered and geometrically standardized using projective standardization. Bone chips were dry ashed and analyzed for calcium content using atomic absorption. No significant difference was found between the radiographic estimates of bone loss from the different bone chip orientations (Wilcoxon: P > 0.05). The correlation between the two series of estimates for all rotations was 0.93 (Spearman: P < 0.05). Linear regression analysis indicated that both correlates did not differ appreciably ( and ). It is concluded that the spatial orientation of arbitrarily shaped bone chips does not have a significant impact on quantitative estimates of changes in bone mass in digital subtraction radiography. These results were obtained in the presence of irreversible projection errors of up to six degrees and after application of projective standardization for image reconstruction and image registration.

Prevalence of calcified carotid artery on panoramic radiographs in postmenopausal women.

PubMed

Taheri, Jamileh Beigom; Moshfeghi, Mahkameh

2009-01-01

This study was designed to evaluate the prevalence of calcified carotid artery in 50 year-old and older postmenopausal dental outpatients for early diagnosis of individuals at risk of stroke. This is a descriptive study of 200 panoramic radiographs. These radiographs included post-menopausal women referring to the Department of Oral Medicine at Shahid Beheshti Faculty of Dentistry during 2006-2007. The x-ray machine, developer and film type were the same for all the radiographs. Statistical analysis included chi-square test and Fisher's exact test. We found 22 calcified carotid arteries. The left and right carotid arteries were involved in 7 and 9 cases, respec-tively. In 6 cases both carotid arteries were calcified. Four individuals had no vascular risk factor excluding age and others had at least one risk factor. We found significant statistical correlation between hypertension, past history of myocardial infarction, and hypercholesterolemia with calcified carotid artery on panoramic radiographs. Under the limitations of the present study, prevalence of calcified carotid arteries is 11.0 % in 50 year-old and older postmenopausal dental outpatients.

Visualization of cavitation phenomena in a Diesel engine fuel injection nozzle by neutron radiography

NASA Astrophysics Data System (ADS)

Takenaka, N.; Kadowaki, T.; Kawabata, Y.; Lim, I. C.; Sim, C. M.

2005-04-01

Visualization of cavitation phenomena in a Diesel engine fuel injection nozzle was carried out by using neutron radiography system at KUR in Research Reactor Institute in Kyoto University and at HANARO in Korea Atomic Energy Research Institute. A neutron chopper was synchronized to the engine rotation for high shutter speed exposures. A multi-exposure method was applied to obtain a clear image as an ensemble average of the synchronized images. Some images were successfully obtained and suggested new understanding of the cavitation phenomena in a Diesel engine fuel injection nozzle.

Mandibular Inferior Cortical Bone Thickness on Panoramic Radiographs in Patients using Bisphosphonates

PubMed Central

Torres, Sandra R.; Chen, Curtis S. K.; Leroux, Brian G.; Lee, Peggy P.; Hollender, Lars G.; Lloid, Michelle; Drew, Shane Patrick; Schubert, Mark M.

2015-01-01

Objective To detect dimensional changes in the mandibular cortical bone associated with bisphosphonate (BP) use and to correlate the measurements of the cortical bone with the cumulative dose of BP therapy. Methods Mandibular inferior cortical bone thickness (MICBT) was measured under the mental foramen from panoramic radiographs of subjects using BP with and without bisphosphonate related osteonecrosis of the jaws (BRONJ) and controls. Results The highest mean MICBT was observed in BRONJ subjects 6.81 (± 1.35 mm), when compared to subjects using BP 5.44 (± 1.09 mm) and controls 4.79 (± 0.85 mm; p<0.01). The mean MICBT of BRONJ subjects was significantly higher than that of subjects using BP without BRONJ. There was a correlation between MICBT and cumulative dose of zolendronate. Conclusion The MICBT on panoramic radiograph is a potentially useful tool for the detection of dimensional changes associated with BP therapy. PMID:25864820

Transitioning to digital radiography.

PubMed

Drost, Wm Tod

2011-04-01

To describe the different forms of digital radiography (DR), image file formats, supporting equipment and services required for DR, storage of digital images, and teleradiology. Purchasing a DR system is a major investment for a veterinary practice. Types of DR systems include computed radiography, charge coupled devices, and direct or indirect DR. Comparison of workflow for analog and DR is presented. On the surface, switching to DR involves the purchase of DR acquisition hardware. The X-ray machine, table and grids used in analog radiography are the same for DR. Realistically, a considerable infrastructure supports the image acquisition hardware. This infrastructure includes monitors, computer workstations, a robust computer network and internet connection, a plan for storage and back up of images, and service contracts. Advantages of DR compared with analog radiography include improved image quality (when used properly), ease of use (more forgiving to the errors of radiographic technique), speed of making a complete study (important for critically ill patients), fewer repeat radiographs, less time looking for imaging studies, less physical storage space, and the ability to easily send images for consultation. With an understanding of the infrastructure requirements, capabilities and limitations of DR, an informed veterinary practice should be better able to make a sound decision about transitioning to DR. © Veterinary Emergency and Critical Care Society 2011.

Correlation of Condylar Guidance Determined by Panoramic Radiographs to One Determined by Conventional Methods.

PubMed

Godavarthi, A Sowjanya; Sajjan, M C Suresh; Raju, A V Rama; Rajeshkumar, P; Premalatha, Averneni; Chava, Narayana

2015-08-01

To evaluate the feasibility of using panoramic radiographs as an alternative to an interocclusal recording method for determining the condylar guidance in dentate and edentulous conditions. 20 dentulous individuals with an age range of 20-30 years and 20 edentulous patients of 40-65 years were selected. An interocclusal bite registration was done in protrusive position for all the subjects. Orthopantomographs were made for all patients in open mouth position. Hanau articulator was modified to record the angulations to the accuracy of 1°. Tracing of glenoid fossa on radiograph was done to measure the condylar guidance angles. Readings were recorded and analyzed by Freidman's test and t-test. Condylar guidance values obtained by the interocclusal method and radiographic method in dentate individuals on the right side and left side 40.55°, and 37.1°, and 40.15°, and 34.75°, respectively. In the edentulous individuals, the values on the right side and left side was 36.7° and 36.1° and 35.95° and 33.6,° respectively. The difference was statistically significant (P = < 0.001) in dentate group and was not statistically significant (P = 0.6493) in edentulous group. Panoramic radiograph can be used as an alternative to interocclusal technique only in edentulous patients. Further studies comparing panoramic radiograph to jaw tracking devices would substantiate the results of this study.

Using Vertical Panoramic Images to Record a Historic Cemetery

NASA Astrophysics Data System (ADS)

Tommaselli, A. M. G.; Polidori, L.; Hasegawa, J. K.; Camargo, P. O.; Hirao, H.; Moraes, M. V. A.; Rissate, E. A., Jr.; Henrique, G. R.; Abreu, P. A. G.; Berveglieri, A.; Marcato, J., Jr.

2013-07-01

In 1919, during colonization of the West Region of São Paulo State, Brazil, the Ogassawara family built a cemetery and a school with donations received from the newspaper Osaka Mainichi Shimbum, in Osaka, Japan. The cemetery was closed by President Getúlio Vargas in 1942, during the Second World War. The architecture of the Japanese cemetery is a unique feature in Latin America. Even considering its historical and cultural relevance, there is a lack of geometric documentation about the location and features of the tombs and other buildings within the cemetery. As an alternative to provide detailed and fast georeferenced information about the area, it is proposed to use near vertical panoramic images taken with a digital camera with fisheye lens as the primary data followed by bundle adjustment and photogrammetric restitution. The aim of this paper is to present a feasibility study on the proposed technique with the assessment of the results with a strip of five panoramic images, taken over some graves in the Japanese cemetery. The results showed that a plant in a scale of 1 : 200 can be produced with photogrammetric restitution at a very low cost, when compared to topographic surveying or laser scanning. The paper will address the main advantages of this technique as well as its drawbacks, with quantitative analysis of the results achieved in this experiment.

Design of a panoramic long-wave infrared athermal system

NASA Astrophysics Data System (ADS)

Yao, Yuan; Geng, Anbing; Bai, Jian; Wang, Haitao; Guo, Jie; Xiong, Tao; Luo, Yujie; Huang, Zhi; Hou, Xiyun

2016-12-01

A panoramic long-wave infrared athermal system is introduced in this paper. The proposed system includes a panoramic annular lens (PAL) block providing a stereo field of view of (30 deg - 100 deg) × 360 deg without the need to move its components. Moreover, to ensure the imaging quality at different temperatures, a refractive/diffractive hybrid lens is introduced to achieve optical passive athermalization. The system operates in a spectral band between 8 and 12 μm, with a total length of 175 mm and a focal length of 3.4 mm. To get a bright and clear image, the aperture of the system was set to f/1.15. The introduction of aspherical surface and even-order diffractive surface not only eliminates the differential thermal but also makes the structure simple and lightweight and improves the image quality. The results show that the modulation transfer function below 20 lp/mm of the system is above 0.2 at each temperature ranging from -20°C to +60°C, which is close to the diffraction limit. The system is suitable to be applied in an uncooled infrared focal plane array detector and will serve as a static alert system. It has a number of pixels of 640×480, and the pixel size is 25 μm.

Sex estimation based on tooth measurements using panoramic radiographs.

PubMed

Capitaneanu, Cezar; Willems, Guy; Jacobs, Reinhilde; Fieuws, Steffen; Thevissen, Patrick

2017-05-01

Sex determination is an important step in establishing the biological profile of unidentified human remains. The aims of the study were, firstly, to assess the degree of sexual dimorphism in permanent teeth, based on digital tooth measurements performed on panoramic radiographs. Secondly, to identify sex-related tooth position-specific measurements or combinations of such measurements, and to assess their applicability for potential sex determination. Two hundred digital panoramic radiographs (100 males, 100 females; age range 22-34 years) were retrospectively collected from the dental clinic files of the Dentomaxillofacial Radiology Center of the University Hospitals Leuven, Belgium, and imported in image enhancement software. Tooth length- and width-related variables were measured on all teeth in upper and lower left quadrant, and ratios of variables were calculated. Univariate and multivariate analyses were performed to quantify the sex discriminative value of the tooth position-specific variables and their combinations. The mandibular and maxillary canine showed the greatest sexual dimorphism, and tooth length variables had the highest discriminative potential. Compared to single variables, combining variables or ratios of variables did not improve substantially the discrimination between males and females. Considering that the discriminative ability values (area under the curve (AUC)) were not higher than 0.80, it is not advocated to use the currently studied dental variables for accurate sex estimation in forensic practice.

2. A panoramic view of the historical district as seen ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. A panoramic view of the historical district as seen from the top of the Waterford Towers. This picture shows the Town Street bridge in the foreground, the Broad Street bridge in the background, Central High School on the left and the Columbus skyline on the right (facing north), and Bicentennial Park just below. - Broad Street Bridge, Spanning Scioto River at U.S. Route 40 (Broad Street), Columbus, Franklin County, OH

Panoramic view of the electrical Department & Boiler House Complex, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Panoramic view of the electrical Department & Boiler House Complex, looking southwest from the roof of the lower shops. Originally constructed in 1888, only sections of original walls remain. In the right foreground is the no. 2 steel foundry, originally constructed in 1888 and converted many times as different furnaces were added. Behind the buildings (to the south and west) is the Stony Creek River. - Johnson Steel Street Rail Company, Electrical Department & Boiler House, 525 Central Avenue, Johnstown, Cambria County, PA

3D reconstruction based on compressed-sensing (CS)-based framework by using a dental panoramic detector.

PubMed

Je, U K; Cho, H M; Hong, D K; Cho, H S; Park, Y O; Park, C K; Kim, K S; Lim, H W; Kim, G A; Park, S Y; Woo, T H; Cho, S I

2016-01-01

In this work, we propose a practical method that can combine the two functionalities of dental panoramic and cone-beam CT (CBCT) features in one by using a single panoramic detector. We implemented a CS-based reconstruction algorithm for the proposed method and performed a systematic simulation to demonstrate its viability for 3D dental X-ray imaging. We successfully reconstructed volumetric images of considerably high accuracy by using a panoramic detector having an active area of 198.4 mm × 6.4 mm and evaluated the reconstruction quality as a function of the pitch (p) and the angle step (Δθ). Our simulation results indicate that the CS-based reconstruction almost completely recovered the phantom structures, as in CBCT, for p≤2.0 and θ≤6°, indicating that it seems very promising for accurate image reconstruction even for large-pitch and few-view data. We expect the proposed method to be applicable to developing a cost-effective, volumetric dental X-ray imaging system. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Three-dimensional analysis of cervical spine segmental motion in rotation.

PubMed

Zhao, Xiong; Wu, Zi-Xiang; Han, Bao-Jun; Yan, Ya-Bo; Zhang, Yang; Lei, Wei

2013-06-20

The movements of the cervical spine during head rotation are too complicated to measure using conventional radiography or computed tomography (CT) techniques. In this study, we measure three-dimensional segmental motion of cervical spine rotation in vivo using a non-invasive measurement technique. Sixteen healthy volunteers underwent three-dimensional CT of the cervical spine during head rotation. Occiput (Oc) - T1 reconstructions were created of volunteers in each of 3 positions: supine and maximum left and right rotations of the head with respect to the bosom. Segmental motions were calculated using Euler angles and volume merge methods in three major planes. Mean maximum axial rotation of the cervical spine to one side was 1.6° to 38.5° at each level. Coupled lateral bending opposite to lateral bending was observed in the upper cervical levels, while in the subaxial cervical levels, it was observed in the same direction as axial rotation. Coupled extension was observed in the cervical levels of C5-T1, while coupled flexion was observed in the cervical levels of Oc-C5. The three-dimensional cervical segmental motions in rotation were accurately measured with the non-invasive measure. These findings will be helpful as the basis for understanding cervical spine movement in rotation and abnormal conditions. The presented data also provide baseline segmental motions for the design of prostheses for the cervical spine.

Optics of wide-angle panoramic viewing system-assisted vitreous surgery.

PubMed

Chalam, Kakarla V; Shah, Vinay A

2004-01-01

The purpose of the article is to describe the optics of the contact wide-angle lens system with stereo-reinverter for vitreous surgery. A panoramic viewing system is made up of two components; an indirect ophthalmoscopy lens system for fundus image viewing, which is placed on the patient's cornea as a contact lens, and a separate removable prism system for reinversion of the image mounted on the microscope above the zooming system. The system provides a 104 degrees field of view in a phakic emmetropic eye with minification, which can be magnified by the operating microscope. It permits a binocular stereoptic view even through a small pupil (3 mm) or larger. In an air-filled phakic eye, field of view increases to approximately 130 degrees. The obtained image of the patient's fundus is reinverted to form true, erect, stereoscopic image by the reinversion system. In conclusion, this system permits wide-angle panoramic view of the surgical field. The contact lens neutralizes the optical irregularities of the corneal surface and allows improved visualization in eyes with irregular astigmatism induced by corneal scars. Excellent visualization is achieved in complex clinical situations such as miotic pupils, lenticular opacities, and in air-filled phakic eyes.

A panoramic coded aperture gamma camera for radioactive hotspots localization

NASA Astrophysics Data System (ADS)

Paradiso, V.; Amgarou, K.; Blanc De Lanaute, N.; Schoepff, V.; Amoyal, G.; Mahe, C.; Beltramello, O.; Liénard, E.

2017-11-01

A known disadvantage of the coded aperture imaging approach is its limited field-of-view (FOV), which often results insufficient when analysing complex dismantling scenes such as post-accidental scenarios, where multiple measurements are needed to fully characterize the scene. In order to overcome this limitation, a panoramic coded aperture γ-camera prototype has been developed. The system is based on a 1 mm thick CdTe detector directly bump-bonded to a Timepix readout chip, developed by the Medipix2 collaboration (256 × 256 pixels, 55 μm pitch, 14.08 × 14.08 mm2 sensitive area). A MURA pattern coded aperture is used, allowing for background subtraction without the use of heavy shielding. Such system is then combined with a USB color camera. The output of each measurement is a semi-spherical image covering a FOV of 360 degrees horizontally and 80 degrees vertically, rendered in spherical coordinates (θ,phi). The geometrical shapes of the radiation-emitting objects are preserved by first registering and stitching the optical images captured by the prototype, and applying, subsequently, the same transformations to their corresponding radiation images. Panoramic gamma images generated by using the technique proposed in this paper are described and discussed, along with the main experimental results obtained in laboratories campaigns.

Sensitometric properties of Agfa Dentus OrthoLux, Agfa Dentus ST8G, and Kodak Ektavision panoramic radiographic film.

PubMed

Wakoh, M; Nishikawa, K; Kobayashi, N; Farman, A G; Kuroyanagi, K

2001-02-01

The purpose of this study was to compare the sensitometric properties of and visualization of anatomical structures with Agfa OrthoLux green-sensitive panoramic radiographic film, Agfa ST8G green sensitive panoramic radiographic film, and Kodak Ektavision green-sensitive panoramic radiographic film used in combination with an Agfa Ortho Regular 400 imaging screen, Kodak Ektavision imaging screen, and Kodak Lanex Regular imaging screen. The density response and resolution of panoramic radiographic film/intensifying screen combinations was evaluated by means of Hunter and Driffield curves, modulation transfer functions, and noise-equivalent number of quanta. Image clarity of selected anatomical structures was rated independently by 6 oral and maxillofacial radiologists. The ISO speed for the Agfa OrthoLux panoramic radiographic film combinations was the fastest, and the ISO speed for the Kodak Ektavision green-sensitive panoramic radiographic film combinations was the slowest. The average gradient for the Agfa ST8G systems was relatively steep in comparison with those for the other film/screen combinations. The modulation transfer functions for the Kodak Ektavision film were higher than those for the other films, irrespective of the screen combination used, and those for Agfa OrthoLux film were slightly higher than those for Agfa ST8G film. The noise-equivalent number of quanta for the Agfa ST8G film/screen combinations was lower than those for the other film/screen combinations. The noise-equivalent number of quanta for the Kodak Ektavision film/screen combinations was well within the high-frequency range, whereas Agfa OrthoLux combined with either the Kodak Ektavision imaging screen or the Kodak Lanex Regular imaging screen produced a noise-equivalent number of quanta similar to those of the Kodak Ektavision film/screen combinations in the low-frequency range. Agfa OrthoLux was perceived to provide clearer images of the selected anatomical details than Agfa ST8G

Panoramic View of the Andes Mountains, Chile and Argentina

NASA Technical Reports Server (NTRS)

1992-01-01

This panoramic view of the Andes Mountains of Chile and Argentina (24.5S, 69.5W) is dominated by the yellows and browns of the coastal Atacama Desert and the full width of the Andes altiplano, about 300 miles. Winter snow can be seen capping the 22,000 to 23,000 ft. peaks of the Andes. Wisps of cirrus clouds lie over the altiplano and offshore fog obscures the coast. In the distance, the low Chaco Plain appears green with pastures and agriculture.

In-vivo measurement of dynamic joint motion using high speed biplane radiography and CT: application to canine ACL deficiency.

PubMed

Tashman, Scott; Anderst, William

2003-04-01

Dynamic assessment of three-dimensional (3D) skeletal kinematics is essential for understanding normal joint function as well as the effects of injury or disease. This paper presents a novel technique for measuring in-vivo skeletal kinematics that combines data collected from high-speed biplane radiography and static computed tomography (CT). The goals of the present study were to demonstrate that highly precise measurements can be obtained during dynamic movement studies employing high frame-rate biplane video-radiography, to develop a method for expressing joint kinematics in an anatomically relevant coordinate system and to demonstrate the application of this technique by calculating canine tibio-femoral kinematics during dynamic motion. The method consists of four components: the generation and acquisition of high frame rate biplane radiographs, identification and 3D tracking of implanted bone markers, CT-based coordinate system determination, and kinematic analysis routines for determining joint motion in anatomically based coordinates. Results from dynamic tracking of markers inserted in a phantom object showed the system bias was insignificant (-0.02 mm). The average precision in tracking implanted markers in-vivo was 0.064 mm for the distance between markers and 0.31 degree for the angles between markers. Across-trial standard deviations for tibio-femoral translations were similar for all three motion directions, averaging 0.14 mm (range 0.08 to 0.20 mm). Variability in tibio-femoral rotations was more dependent on rotation axis, with across-trial standard deviations averaging 1.71 degrees for flexion/extension, 0.90 degree for internal/external rotation, and 0.40 degree for varus/valgus rotation. Advantages of this technique over traditional motion analysis methods include the elimination of skin motion artifacts, improved tracking precision and the ability to present results in a consistent anatomical reference frame.

Towards System Calibration of Panoramic Laser Scanners from a Single Station

PubMed Central

Medić, Tomislav; Holst, Christoph; Kuhlmann, Heiner

2017-01-01

Terrestrial laser scanner measurements suffer from systematic errors due to internal misalignments. The magnitude of the resulting errors in the point cloud in many cases exceeds the magnitude of random errors. Hence, the task of calibrating a laser scanner is important for applications with high accuracy demands. This paper primarily addresses the case of panoramic terrestrial laser scanners. Herein, it is proven that most of the calibration parameters can be estimated from a single scanner station without a need for any reference information. This hypothesis is confirmed through an empirical experiment, which was conducted in a large machine hall using a Leica Scan Station P20 panoramic laser scanner. The calibration approach is based on the widely used target-based self-calibration approach, with small modifications. A new angular parameterization is used in order to implicitly introduce measurements in two faces of the instrument and for the implementation of calibration parameters describing genuine mechanical misalignments. Additionally, a computationally preferable calibration algorithm based on the two-face measurements is introduced. In the end, the calibration results are discussed, highlighting all necessary prerequisites for the scanner calibration from a single scanner station. PMID:28513548

Correlation of Condylar Guidance Determined by Panoramic Radiographs to One Determined by Conventional Methods

PubMed Central

Godavarthi, A Sowjanya; Sajjan, M C Suresh; Raju, A V Rama; Rajeshkumar, P; Premalatha, Averneni; Chava, Narayana

2015-01-01

Background: To evaluate the feasibility of using panoramic radiographs as an alternative to an interocclusal recording method for determining the condylar guidance in dentate and edentulous conditions. Materials and Methods: 20 dentulous individuals with an age range of 20-30 years and 20 edentulous patients of 40-65 years were selected. An interocclusal bite registration was done in protrusive position for all the subjects. Orthopantomographs were made for all patients in open mouth position. Hanau articulator was modified to record the angulations to the accuracy of 1°. Tracing of glenoid fossa on radiograph was done to measure the condylar guidance angles. Readings were recorded and analyzed by Freidman’s test and t-test. Results: Condylar guidance values obtained by the interocclusal method and radiographic method in dentate individuals on the right side and left side 40.55°, and 37.1°, and 40.15°, and 34.75°, respectively. In the edentulous individuals, the values on the right side and left side was 36.7° and 36.1° and 35.95° and 33.6,° respectively. The difference was statistically significant (P = < 0.001) in dentate group and was not statistically significant (P = 0.6493) in edentulous group. Conclusion: Panoramic radiograph can be used as an alternative to interocclusal technique only in edentulous patients. Further studies comparing panoramic radiograph to jaw tracking devices would substantiate the results of this study. PMID:26464554

An automatic early stage alveolar-bone-resorption evaluation method on digital dental panoramic radiographs

NASA Astrophysics Data System (ADS)

Zhang, Min; Katsumata, Akitoshi; Muramatsu, Chisako; Hara, Takeshi; Suzuki, Hiroki; Fujita, Hiroshi

2014-03-01

Periodontal disease is a kind of typical dental diseases, which affects many adults. The presence of alveolar bone resorption, which can be observed from dental panoramic radiographs, is one of the most important signs of the progression of periodontal disease. Automatically evaluating alveolar-bone resorption is of important clinic meaning in dental radiology. The purpose of this study was to propose a novel system for automated alveolar-bone-resorption evaluation from digital dental panoramic radiographs for the first time. The proposed system enables visualization and quantitative evaluation of alveolar bone resorption degree surrounding the teeth. It has the following procedures: (1) pre-processing for a test image; (2) detection of tooth root apices with Gabor filter and curve fitting for the root apex line; (3) detection of features related with alveolar bone by using image phase congruency map and template matching and curving fitting for the alveolar line; (4) detection of occlusion line with selected Gabor filter; (5) finally, evaluation of the quantitative alveolar-bone-resorption degree in the area surrounding teeth by simply computing the average ratio of the height of the alveolar bone and the height of the teeth. The proposed scheme was applied to 30 patient cases of digital panoramic radiographs, with alveolar bone resorption of different stages. Our initial trial on these test cases indicates that the quantitative evaluation results are correlated with the alveolar-boneresorption degree, although the performance still needs further improvement. Therefore it has potential clinical practicability.

10 CFR 34.13 - Specific license for industrial radiography.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 1 2014-01-01 2014-01-01 false Specific license for industrial radiography. 34.13 Section 34.13 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY... safety responsibilities in industrial radiography, including specified delegation of authority and...

10 CFR 34.13 - Specific license for industrial radiography.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 1 2013-01-01 2013-01-01 false Specific license for industrial radiography. 34.13 Section 34.13 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY... safety responsibilities in industrial radiography, including specified delegation of authority and...

10 CFR 34.13 - Specific license for industrial radiography.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 1 2011-01-01 2011-01-01 false Specific license for industrial radiography. 34.13 Section 34.13 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY... safety responsibilities in industrial radiography, including specified delegation of authority and...

10 CFR 34.13 - Specific license for industrial radiography.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 1 2012-01-01 2012-01-01 false Specific license for industrial radiography. 34.13 Section 34.13 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY... safety responsibilities in industrial radiography, including specified delegation of authority and...

The Mars NetLander panoramic camera

NASA Astrophysics Data System (ADS)

Jaumann, Ralf; Langevin, Yves; Hauber, Ernst; Oberst, Jürgen; Grothues, Hans-Georg; Hoffmann, Harald; Soufflot, Alain; Bertaux, Jean-Loup; Dimarellis, Emmanuel; Mottola, Stefano; Bibring, Jean-Pierre; Neukum, Gerhard; Albertz, Jörg; Masson, Philippe; Pinet, Patrick; Lamy, Philippe; Formisano, Vittorio

2000-10-01

The panoramic camera (PanCam) imaging experiment is designed to obtain high-resolution multispectral stereoscopic panoramic images from each of the four Mars NetLander 2005 sites. The main scientific objectives to be addressed by the PanCam experiment are (1) to locate the landing sites and support the NetLander network sciences, (2) to geologically investigate and map the landing sites, and (3) to study the properties of the atmosphere and of variable phenomena. To place in situ measurements at a landing site into a proper regional context, it is necessary to determine the lander orientation on ground and to exactly locate the position of the landing site with respect to the available cartographic database. This is not possible by tracking alone due to the lack of on-ground orientation and the so-called map-tie problem. Images as provided by the PanCam allow to determine accurate tilt and north directions for each lander and to identify the lander locations based on landmarks, which can also be recognized in appropriate orbiter imagery. With this information, it will be further possible to improve the Mars-wide geodetic control point network and the resulting geometric precision of global map products. The major geoscientific objectives of the PanCam lander images are the recognition of surface features like ripples, ridges and troughs, and the identification and characterization of different rock and surface units based on their morphology, distribution, spectral characteristics, and physical properties. The analysis of the PanCam imagery will finally result in the generation of precise map products for each of the landing sites. So far comparative geologic studies of the Martian surface are restricted to the timely separated Mars Pathfinder and the two Viking Lander Missions. Further lander missions are in preparation (Beagle-2, Mars Surveyor 03). NetLander provides the unique opportunity to nearly double the number of accessible landing site data by providing

Embossed radiography utilizing energy subtraction.

PubMed

Osawa, Akihiro; Watanabe, Manabu; Sato, Eiichi; Matsukiyo, Hiroshi; Enomoto, Toshiyuki; Nagao, Jiro; Abderyim, Purkhet; Aizawa, Katsuo; Tanaka, Etsuro; Mori, Hidezo; Kawai, Toshiaki; Ehara, Shigeru; Sato, Shigehiro; Ogawa, Akira; Onagawa, Jun

2009-01-01

Currently, it is difficult to carry out refraction-contrast radiography by using a conventional X-ray generator. Thus, we developed an embossed radiography system utilizing dual-energy subtraction for decreasing the absorption contrast in unnecessary regions, and the contrast resolution of a target region was increased by use of image-shifting subtraction and a linear-contrast system in a flat panel detector (FPD). The X-ray generator had a 100-microm-focus tube. Energy subtraction was performed at tube voltages of 45 and 65 kV, a tube current of 0.50 mA, and an X-ray exposure time of 5.0 s. A 1.0-mm-thick aluminum filter was used for absorbing low-photon-energy bremsstrahlung X-rays. Embossed radiography was achieved with cohesion imaging by use of the FPD with pixel sizes of 48 x 48 microm, and the shifting dimension of an object in the horizontal direction ranged from 100 to 200 microm. At a shifting distance of 100 mum, the spatial resolutions in the horizontal and vertical directions measured with a lead test chart were both 83 microm. In embossed radiography of non-living animals, we obtained high-contrast embossed images of fine bones, gadolinium oxide particles in the kidney, and coronary arteries approximately 100 microm in diameter.

Multi-Institutional Evaluation of Digital Tomosynthesis, Dual-Energy Radiography, and Conventional Chest Radiography for the Detection and Management of Pulmonary Nodules.

PubMed

Dobbins, James T; McAdams, H Page; Sabol, John M; Chakraborty, Dev P; Kazerooni, Ella A; Reddy, Gautham P; Vikgren, Jenny; Båth, Magnus

2017-01-01

Purpose To conduct a multi-institutional, multireader study to compare the performance of digital tomosynthesis, dual-energy (DE) imaging, and conventional chest radiography for pulmonary nodule detection and management. Materials and Methods In this binational, institutional review board-approved, HIPAA-compliant prospective study, 158 subjects (43 subjects with normal findings) were enrolled at four institutions. Informed consent was obtained prior to enrollment. Subjects underwent chest computed tomography (CT) and imaging with conventional chest radiography (posteroanterior and lateral), DE imaging, and tomosynthesis with a flat-panel imaging device. Three experienced thoracic radiologists identified true locations of nodules (n = 516, 3-20-mm diameters) with CT and recommended case management by using Fleischner Society guidelines. Five other radiologists marked nodules and indicated case management by using images from conventional chest radiography, conventional chest radiography plus DE imaging, tomosynthesis, and tomosynthesis plus DE imaging. Sensitivity, specificity, and overall accuracy were measured by using the free-response receiver operating characteristic method and the receiver operating characteristic method for nodule detection and case management, respectively. Results were further analyzed according to nodule diameter categories (3-4 mm, >4 mm to 6 mm, >6 mm to 8 mm, and >8 mm to 20 mm). Results Maximum lesion localization fraction was higher for tomosynthesis than for conventional chest radiography in all nodule size categories (3.55-fold for all nodules, P < .001; 95% confidence interval [CI]: 2.96, 4.15). Case-level sensitivity was higher with tomosynthesis than with conventional chest radiography for all nodules (1.49-fold, P < .001; 95% CI: 1.25, 1.73). Case management decisions showed better overall accuracy with tomosynthesis than with conventional chest radiography, as given by the area under the receiver operating characteristic curve

Photocopy of panoramic photograph entitled "Ground Breaking, April 27, 1918, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Photocopy of panoramic photograph entitled "Ground Breaking, April 27, 1918, U.S.A. General Hospital no. 21…". Photograph by Rocky Mountain photo and is in the Fitzsimons Army Medical Center Public Affairs Office, building 120. Photograph in public domain as it is not copyrighted. - Fitzsimons General Hospital, Bounded by East Colfax to south, Peoria Street to west, Denver City/County & Adams County Line to north, & U.S. Route 255 to east, Aurora, Adams County, CO

TREAT neutron-radiography facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harrison, L.J.

1981-01-01

The TREAT reactor was built as a transient irradiation test reactor. By taking advantage of built-in system features, it was possible to add a neutron-radiography facility. This facility has been used over the years to radiograph a wide variety and large number of preirradiated fuel pins in many different configurations. Eight different specimen handling casks weighing up to 54.4 t (60 T) can be accommodated. Thermal, epithermal, and track-etch radiographs have been taken. Neutron-radiography service can be provided for specimens from other reactor facilities, and the capacity for storing preirradiated specimens also exists.

Digital radiography: a survey of pediatric dentists.

PubMed

Russo, Julie M; Russo, James A; Guelmann, Marcio

2006-01-01

The purpose of this study was to: (1) determine the popularity of digital radiography among members of the American Academy of Pediatric Dentistry (AAPD); and (2) report the most common systems in use. An AAPD-approved, voluntary, and anonymous electronic survey was developed and sent to 923 board certified pediatric dentists. Years in practice and in-office x-ray technology (digital or conventional) were inquired about initially. If negative for the use of digital radiography, future consideration for converting to digital radiography was ascertained. For positive responses, more in-depth information was requested. Information on type of system (sensor or phosphor plate), user friendliness, diagnostic ability, patient's comfort, general costs, durability, and parental and overall satisfaction was collected. For most of the questions, a 5-point assessment scale was used. Opportunity for additional comments was provided upon survey completion. Data was analyzed using descriptive statistics. A 32% (296/923) response rate was obtained. Twenty-six percent of practitioners (78/296) implemented digital radiography in their practices, whereas 71% considered future acquisition. Similar distribution for sensor and phosphor plate users was found. Sensor technology was reported to produce faster images, but was less tolerable by young children due to size and thickness. Phosphor plates were considered more children friendly, less expensive, and less durable. Parental satisfaction was very high with great marketing value. Picture quality was comparable to conventional film. Overall, digital radiography users would recommend it to other pediatric dentists. Digital radiography is not yet popular among pediatric dentists. Cost reduction and technology advancement may enhance utilization.

Simultaneous wood and metal particle detection on dark-field radiography.

PubMed

Braig, Eva-Maria; Birnbacher, Lorenz; Schaff, Florian; Gromann, Lukas; Fingerle, Alexander; Herzen, Julia; Rummeny, Ernst; Noël, Peter; Pfeiffer, Franz; Muenzel, Daniela

2018-01-01

Currently, the detection of retained wood is a frequent but challenging task in emergency care. The purpose of this study is to demonstrate improved foreign-body detection with the novel approach of preclinical X-ray dark-field radiography. At a preclinical dark-field x-ray radiography, setup resolution and sensitivity for simultaneous detection of wooden and metallic particles have been evaluated in a phantom study. A clinical setting has been simulated with a formalin fixated human hand where different typical foreign-body materials have been inserted. Signal-to-noise ratios (SNR) have been determined for all test objects. On the phantom, the SNR value for wood in the dark-field channel was strongly improved by a factor 6 compared to conventional radiography and even compared to the SNR of an aluminium structure of the same size in conventional radiography. Splinters of wood < 300 μm in diameter were clearly detected on the dark-field radiography. Dark-field radiography of the formalin-fixated human hand showed a clear signal for wooden particles that could not be identified on conventional radiography. x-ray dark-field radiography enables the simultaneous detection of wooden and metallic particles in the extremities. It has the potential to improve and simplify the current state-of-the-art foreign-body detection.

Multi-Institutional Evaluation of Digital Tomosynthesis, Dual-Energy Radiography, and Conventional Chest Radiography for the Detection and Management of Pulmonary Nodules

PubMed Central

McAdams, H. Page; Sabol, John M.; Chakraborty, Dev P.; Kazerooni, Ella A.; Reddy, Gautham P.; Vikgren, Jenny; Båth, Magnus

2017-01-01

Purpose To conduct a multi-institutional, multireader study to compare the performance of digital tomosynthesis, dual-energy (DE) imaging, and conventional chest radiography for pulmonary nodule detection and management. Materials and Methods In this binational, institutional review board–approved, HIPAA-compliant prospective study, 158 subjects (43 subjects with normal findings) were enrolled at four institutions. Informed consent was obtained prior to enrollment. Subjects underwent chest computed tomography (CT) and imaging with conventional chest radiography (posteroanterior and lateral), DE imaging, and tomosynthesis with a flat-panel imaging device. Three experienced thoracic radiologists identified true locations of nodules (n = 516, 3–20-mm diameters) with CT and recommended case management by using Fleischner Society guidelines. Five other radiologists marked nodules and indicated case management by using images from conventional chest radiography, conventional chest radiography plus DE imaging, tomosynthesis, and tomosynthesis plus DE imaging. Sensitivity, specificity, and overall accuracy were measured by using the free-response receiver operating characteristic method and the receiver operating characteristic method for nodule detection and case management, respectively. Results were further analyzed according to nodule diameter categories (3–4 mm, >4 mm to 6 mm, >6 mm to 8 mm, and >8 mm to 20 mm). Results Maximum lesion localization fraction was higher for tomosynthesis than for conventional chest radiography in all nodule size categories (3.55-fold for all nodules, P < .001; 95% confidence interval [CI]: 2.96, 4.15). Case-level sensitivity was higher with tomosynthesis than with conventional chest radiography for all nodules (1.49-fold, P < .001; 95% CI: 1.25, 1.73). Case management decisions showed better overall accuracy with tomosynthesis than with conventional chest radiography, as given by the area under the receiver operating characteristic

National reference doses for dental cephalometric radiography.

PubMed

Holroyd, J R

2011-12-01

Diagnostic reference levels (DRLs) are an important tool in the optimisation of clinical radiography. Although national DRLs are provided for many diagnostic procedures including dental intra-oral radiography, there are currently no national DRLs set for cephalometric radiography. In the absence of formal national DRLs, the Health Protection Agency (HPA) has previously published National Reference Doses (NRDs) covering a wide range of diagnostic X-ray examinations. The aim of this study was to determine provisional NRDs for cephalometric radiography. Measurements made by the Dental X-ray Protection Service (DXPS) of the HPA, as part of the cephalometric X-ray equipment testing service provided to dentists and dental trade companies throughout the UK, were used to derive provisional NRDs. Dose-area product measurements were made on 42 X-ray sets. Third quartile dose-area product values for adult and child lateral cephalometric radiography were found to be 41 mGy cm² and 25 mGy cm², respectively, with individual measurements ranging from 3 mGy cm² to 108 mGy cm². This report proposes provisional NRDs of 40 mGy cm² and 25 mGy cm² for adult and child lateral cephalometric radiographs, respectively; these doses could be considered by employers when establishing their local DRLs.

Vertebral rotation measurement: a summary and comparison of common radiographic and CT methods

PubMed Central

Lam, Gabrielle C; Hill, Doug L; Le, Lawrence H; Raso, Jim V; Lou, Edmond H

2008-01-01

Current research has provided a more comprehensive understanding of Adolescent Idiopathic Scoliosis (AIS) as a three-dimensional spinal deformity, encompassing both lateral and rotational components. Apart from quantifying curve severity using the Cobb angle, vertebral rotation has become increasingly prominent in the study of scoliosis. It demonstrates significance in both preoperative and postoperative assessment, providing better appreciation of the impact of bracing or surgical interventions. In the past, the need for computer resources, digitizers and custom software limited studies of rotation to research performed after a patient left the scoliosis clinic. With advanced technology, however, rotation measurements are now more feasible. While numerous vertebral rotation measurement methods have been developed and tested, thorough comparisons of these are still relatively unexplored. This review discusses the advantages and disadvantages of six common measurement techniques based on technology most pertinent in clinical settings: radiography (Cobb, Nash-Moe, Perdriolle and Stokes' method) and computer tomography (CT) imaging (Aaro-Dahlborn and Ho's method). Better insight into the clinical suitability of rotation measurement methods currently available is presented, along with a discussion of critical concerns that should be addressed in future studies and development of new methods. PMID:18976498

Automatic Molar Extraction from Dental Panoramic Radiographs for Forensic Personal Identification

NASA Astrophysics Data System (ADS)

Samopa, Febriliyan; Asano, Akira; Taguchi, Akira

Measurement of an individual molar provides rich information for forensic personal identification. We propose a computer-based system for extracting an individual molar from dental panoramic radiographs. A molar is obtained by extracting the region-of-interest, separating the maxilla and mandible, and extracting the boundaries between teeth. The proposed system is almost fully automatic; all that the user has to do is clicking three points on the boundary between the maxilla and the mandible.

Accuracy of imaging methods for detection of bone tissue invasion in patients with oral squamous cell carcinoma

PubMed Central

Uribe, S; Rojas, LA; Rosas, CF

2013-01-01

The objective of this review is to evaluate the diagnostic accuracy of imaging methods for detection of mandibular bone tissue invasion by squamous cell carcinoma (SCC). A systematic review was carried out of studies in MEDLINE, SciELO and ScienceDirect, published between 1960 and 2012, in English, Spanish or German, which compared detection of mandibular bone tissue invasion via different imaging tests against a histopathology reference standard. Sensitivity and specificity data were extracted from each study. The outcome measure was diagnostic accuracy. We found 338 articles, of which 5 fulfilled the inclusion criteria. Tests included were: CT (four articles), MRI (four articles), panoramic radiography (one article), positron emission tomography (PET)/CT (one article) and cone beam CT (CBCT) (one article). The quality of articles was low to moderate and the evidence showed that all tests have a high diagnostic accuracy for detection of mandibular bone tissue invasion by SCC, with sensitivity values of 94% (MRI), 91% (CBCT), 83% (CT) and 55% (panoramic radiography), and specificity values of 100% (CT, MRI, CBCT), 97% (PET/CT) and 91.7% (panoramic radiography). Available evidence is scarce and of only low to moderate quality. However, it is consistently shown that current imaging methods give a moderate to high diagnostic accuracy for the detection of mandibular bone tissue invasion by SCC. Recommendations are given for improving the quality of future reports, in particular provision of a detailed description of the patients' conditions, the imaging instrument and both imaging and histopathological invasion criteria. PMID:23420854

9. THIRD IMAGE OF THE PANORAMIC SERIES WITH CONSIDERABLE OVERLAP. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. THIRD IMAGE OF THE PANORAMIC SERIES WITH CONSIDERABLE OVERLAP. A SETTLING TANK, SMOKESTACK FROM THE MILL'S BOILER ROOM, MILL ANNEX AND OTHER MILL OUT BUILDINGS ARE IN THE MIDDLE RIGHT OF THE IMAGE THE SUPERINTENDENTS HOUSE IS IN THE MIDDLE LEFT OF THE IMAGE SPANNING FROM LEFT TO RIGHT IN THE BACKGROUND IS THE TOWN OF BODIE. IN THE FAR BACKGROUND LEFT IS THE ROAD THAT IS THE ACCESS PARK. - Standard Gold Mill, East of Bodie Creek, Northeast of Bodie, Bodie, Mono County, CA

Trochoidal X-ray Vector Radiography: Directional dark-field without grating stepping

NASA Astrophysics Data System (ADS)

Sharma, Y.; Bachche, S.; Kageyama, M.; Kuribayashi, M.; Pfeiffer, F.; Lasser, T.; Momose, A.

2018-03-01

X-ray Vector Radiography (XVR) is an imaging technique that reveals the orientations of sub-pixel sized structures within a sample. Several dark-field radiographs are acquired by rotating the sample around the beam propagation direction and stepping one of the gratings to several positions for every pose of the sample in an X-ray grating interferometry setup. In this letter, we present a method of performing XVR of a continuously moving sample without the need of any grating motion. We reconstruct the orientations within a sample by analyzing the change in the background moire fringes caused by the sample moving and simultaneously rotating in plane (trochoidal trajectory) across the detector field-of-view. Avoiding the motion of gratings provides significant advantages in terms of stability and repeatability, while the continuous motion of the sample makes this kind of system adaptable for industrial applications such as the scanning of samples on a conveyor belt. Being the first step in the direction of utilizing advanced sample trajectories to replace grating motion, this work also lays the foundations for a full three dimensional reconstruction of scattering function without grating motion.

Digital radiography in space.

PubMed

Hart, Rob; Campbell, Mark R

2002-06-01

With the permanent habitation of the International Space Station, the planning of longer duration exploration missions, and the possibility of space tourism, it is likely that digital radiography will be needed in the future to support medical care in space. Ultrasound is currently the medical imaging modality of choice for spaceflight. Digital radiography in space is limited because of prohibitive launch costs (in the region of $20,000/kg) that severely restrict the volume, weight, and power requirements of medical care hardware. Technological increases in radiography, a predicted ten-fold decrease in future launch costs, and an increasing clinical need for definitive medical care in space will drive efforts to expand the ability to provide medical care in space including diagnostic imaging. Normal physiological responses to microgravity, in conjunction with the high-risk environment of spaceflight, increase the risk of injury and could imply an extended recovery period for common injuries. The advantages of gravity on Earth, such as the stabilization of patients undergoing radiography and the drainage of fluids, which provide radiographic contrast, are unavailable in space. This creates significant difficulties in patient immobilization and radiographic positioning. Gravity-dependent radiological signs, such as lipohemarthrosis in knee and shoulder trauma, air or fluid levels in pneumoperitoneum, pleural effusion, or bowel obstruction, and the apical pleural edge in pneumothorax become unavailable. Impaired healing processes such as delayed callus formation following fracture will have implications on imaging, and recovery time lines are unknown. The confined nature of spacecraft and the economic impossibility of launching lead-based personal protective equipment present significant challenges to crew radiation safety. A modified, free-floating radiographic C-arm device equipped with a digital detector and utilizing teleradiology support is proposed as a

Complications of rotator cuff surgery—the role of post-operative imaging in patient care

PubMed Central

Thakkar, R S; Thakkar, S C; Srikumaran, U; Fayad, L M

2014-01-01

When pain or disability occurs after rotator cuff surgery, post-operative imaging is frequently performed. Post-operative complications and expected post-operative imaging findings in the shoulder are presented, with a focus on MRI, MR arthrography (MRA) and CT arthrography. MR and CT techniques are available to reduce image degradation secondary to surgical distortions of native anatomy and implant-related artefacts and to define complications after rotator cuff surgery. A useful approach to image the shoulder after surgery is the standard radiography, followed by MRI/MRA for patients with low “metal presence” and CT for patients who have a higher metal presence. However, for the assessment of patients who have undergone surgery for rotator cuff injuries, imaging findings should always be correlated with the clinical presentation because post-operative imaging abnormalities do not necessarily correlate with symptoms. PMID:24734935

INDUSTRIAL RADIOGRAPHY STUDENT GUIDE AND LABORATORY EXERCISES.

ERIC Educational Resources Information Center

Bureau of Adult, Vocational, and Technical Education (DHEW/OE), Washington, DC. Div. of Vocational and Technical Education.

THIS INSTRUCTOR'S GUIDE TO AN 80-HOUR COURSE IN INDUSTRIAL RADIOGRAPHY IS COORDINATED WITH LESSONS IN THE STUDENT GUIDE AND LABORATORY EXERCISES AND IS BASED ON MATERIAL IN THE COURSE MANUAL, INDUSTRIAL RADIOGRAPHY. THE COURSE IS INTENDED TO TRAIN HIGH SCHOOL GRADUATES AS BEGINNING RADIOGRAPHERS WHO ARE EXPECTED TO BE ABLE TO EXTEND THEIR…

7. THE BEGINNING OF A PANORAMIC SERIES VIEW LOOKING WEST ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. THE BEGINNING OF A PANORAMIC SERIES VIEW LOOKING WEST NORTHWEST FROM THE UPHILL SIDE OF THE MILL. THE ORE RECEIVING HOUSE IS IN THE IMAGE CENTER, THE ORE DELIVERY TRESTLE EXTENDS FROM THE RECEIVING HOUSE TO THE MILL BUILDING IN THE BACKGROUND LEFT. IN THE MID-GROUND LEFT IS A CYLINDRICAL STRUCTURE BELIEVE TO BE A SETTLING TANK FROM A LATER CHEMICAL RETREATMENT OF THE TAILINGS IN THE FOREGROUND RIGHT IS AN EXTANT ORE BUCKET. - Standard Gold Mill, East of Bodie Creek, Northeast of Bodie, Bodie, Mono County, CA

Assessment of medial elbow laxity by gravity stress radiography: comparison of valgus stress radiography with gravity and a Telos stress device.

PubMed

Harada, Mikio; Takahara, Masatoshi; Maruyama, Masahiro; Nemoto, Tadanobu; Koseki, Kazuhiko; Kato, Yoshihiro

2014-04-01

Valgus instability was reported to be higher with the elbow in 60° of flexion, rather than in 30° of flexion, although there are no studies using valgus stress radiography by gravity (gravity radiography) with the elbow in 60° of flexion. Fifty-seven patients with medial elbow pain participated. For both elbows, valgus stress radiography by use of a Telos device (Telos radiography) and gravity radiography, with the elbow in 60° of flexion, were performed for the assessment of medial elbow laxity. In both radiographs, the medial elbow joint space (MJS) on the affected side was compared with that on the opposite side, and the increase in the MJS on the affected side was assessed. For the Telos radiographs, the mean MJS was 4.7 mm on the affected side and 4.0 mm on the opposite side, with the mean increase in the MJS on the affected side being 0.7 mm. For the gravity radiographs, the mean MJS was 5.0 mm on the affected side and 4.2 mm on the opposite side, with the mean increase in the MJS on the affected side being 0.8 mm. There were significant correlations between the Telos and gravity radiographs in the MJS on the affected side, the MJS on the opposite side, and the increase in the MJS on the affected side (respectively, P < .0001). There was also a high level of intraobserver and interobserver reliability for the assessment of the gravity radiographs. Gravity radiography is useful for assessment of medial elbow laxity, similar to Telos radiography. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

Neutron radiography of irradiated nuclear fuel at Idaho National Laboratory

DOE PAGES

Craft, Aaron E.; Wachs, Daniel M.; Okuniewski, Maria A.; ...

2015-09-10

Neutron radiography of irradiated nuclear fuel provides more comprehensive information about the internal condition of irradiated nuclear fuel than any other non-destructive technique to date. Idaho National Laboratory (INL) has multiple nuclear fuels research and development programs that routinely evaluate irradiated fuels using neutron radiography. The Neutron Radiography reactor (NRAD) sits beneath a shielded hot cell facility where neutron radiography and other evaluation techniques are performed on these highly radioactive objects. The NRAD currently uses the foil-film transfer technique for imaging fuel that is time consuming but provides high spatial resolution. This study describes the NRAD and hot cell facilities,more » the current neutron radiography capabilities available at INL, planned upgrades to the neutron imaging systems, and new facilities being brought online at INL related to neutron imaging.« less

Display modes for CT colonography. Part II. Blinded comparison of axial CT and virtual endoscopic and panoramic endoscopic volume-rendered studies.

PubMed

Beaulieu, C F; Jeffrey, R B; Karadi, C; Paik, D S; Napel, S

1999-07-01

To determine the sensitivity of radiologist observers for detecting colonic polyps by using three different data review (display) modes for computed tomographic (CT) colonography, or "virtual colonoscopy." CT colonographic data in a patient with a normal colon were used as base data for insertion of digitally synthesized polyps. Forty such polyps (3.5, 5, 7, and 10 mm in diameter) were randomly inserted in four copies of the base data. Axial CT studies, volume-rendered virtual endoscopic movies, and studies from a three-dimensional mode termed "panoramic endoscopy" were reviewed blindly and independently by two radiologists. Detection improved with increasing polyp size. Trends in sensitivity were dependent on whether all inserted lesions or only visible lesions were considered, because modes differed in how completely the colonic surface was depicted. For both reviewers and all polyps 7 mm or larger, panoramic endoscopy resulted in significantly greater sensitivity (90%) than did virtual endoscopy (68%, P = .014). For visible lesions only, the sensitivities were 85%, 81%, and 60% for one reader and 65%, 62%, and 28% for the other for virtual endoscopy, panoramic endoscopy, and axial CT, respectively. Three-dimensional displays were more sensitive than two-dimensional displays (P < .05). The sensitivity of panoramic endoscopy is higher than that of virtual endoscopy, because the former displays more of the colonic surface. Higher sensitivities for three-dimensional displays may justify the additional computation and review time.

Evaluation of a Noise Reduction Procedure for Chest Radiography

PubMed Central

Fukui, Ryohei; Ishii, Rie; Kodani, Kazuhiko; Kanasaki, Yoshiko; Suyama, Hisashi; Watanabe, Masanari; Nakamoto, Masaki; Fukuoka, Yasushi

2013-01-01

Background The aim of this study was to evaluate the usefulness of noise reduction procedure (NRP), a function in the new image processing for chest radiography. Methods A CXDI-50G Portable Digital Radiography System (Canon) was used for X-ray detection. Image noise was analyzed with a noise power spectrum (NPS) and a burger phantom was used for evaluation of density resolution. The usefulness of NRP was evaluated by chest phantom images and clinical chest radiography. We employed the Bureau of Radiological Health Method for scoring chest images while carrying out our observations. Results NPS through the use of NRP was improved compared with conventional image processing (CIP). The results in image quality showed high-density resolution through the use of NRP, so that chest radiography examination can be performed with a low dose of radiation. Scores were significantly higher than for CIP. Conclusion In this study, use of NRP led to a high evaluation in these so we are able to confirm the usefulness of NRP for clinical chest radiography. PMID:24574577

Comparison of ultrasonography and radiography in diagnosis of rib fractures.

PubMed

Pishbin, Elham; Ahmadi, Koorosh; Foogardi, Molood; Salehi, Maryam; Seilanian Toosi, Farrokh; Rahimi-Movaghar, Vafa

2017-08-01

Rib fractures are the most common skeletal thoracic injuries resulting from blunt chest trauma. Half of the rib fractures are not detected upon a precise physical evaluation and radiographs. Recently ultrasonography (USG) has been investigated to detect rib fractures. But based on literature the usefulness of USG varies widely. This study was conducted to investigate the role of USG in the detection of possible rib fractures in comparison with radiography. In this cross-sectional study, consecutive patients with minor blunt chest trauma and suspected rib fractures presenting in Imam Reza Hospital located in Mashhad-Iran, between April 2013 and October 2013 were assessed by USG and radiography. The radiography was performed in a posteroanterior (PA) chest projection and oblique rib view centered over the area of trauma. The time duration spent in taking USG and radiography were recorded. The prevalence and location of fractures revealed by USG and radiography were compared. Sixty-one suspected patients were assessed. The male to female ratio was 2.4:1 (43 men and 18 women) with a mean ± SD age of (44.3 ± 19.7) years. There were totally 59 rib fractures in 38 (62.3%) patients based on radiography and USG, while 23 (37.7%) patients had no diagnostic evidence of rib lesions. USG revealed 58 rib fractures in 33 (54.1%) of 61 suspected patients and radiographs revealed 32 rib fractures in 20 (32.8%) of 61 patients. A total of 58 (98.3%) rib fractures were detected by USG, whereas oblique rib view and PA chest radiography showed 27 (45.8%) and 24 (40.7%) rib fractures, respectively. The average duration of USG was (12 ± 3) min (range 7-17 min), whereas the duration of radiography was (27 ± 6) min (range 15-37 min). The kappa coefficient showed a low level of agreement between both USG and PA chest radiography (kappa coefficient = 0.28), and between USG and oblique rib view (kappa coefficient = 0.32). USG discloses more fractures than radiography in

Proton Radiography Peers into Metal Solidification

DOE PAGES

Clarke, Amy J.; Imhoff, Seth D.; Gibbs, Paul J.; ...

2013-06-19

Historically, metals are cut up and polished to see the structure and to infer how processing influences the evolution. We can now peer into a metal during processing without destroying it using proton radiography. Understanding the link between processing and structure is important because structure profoundly affects the properties of engineering materials. Synchrotron x-ray radiography has enabled real-time glimpses into metal solidification. However, x-ray energies favor the examination of small volumes and low density metals. In this study, we use high energy proton radiography for the first time to image a large metal volume (>10,000 mm 3) during melting andmore » solidification. We also show complementary x-ray results from a small volume (<1mm 3), bridging four orders of magnitude. In conclusion, real-time imaging will enable efficient process development and the control of the structure evolution to make materials with intended properties; it will also permit the development of experimentally informed, predictive structure and process models.« less

Abdomen X-Ray (Radiography)

MedlinePlus

... News Physician Resources Professions Site Index A-Z X-ray (Radiography) - Abdomen Abdominal x-ray uses a ... of an abdominal x-ray? What is abdominal x-ray? An x-ray (radiograph) is a noninvasive ...

Panoramic radiographic survey of hypodontia in Australian Defence Force recruits.

PubMed

Lynham, A

1990-02-01

Comprehensive dental examinations and panoramic radiographs were used to determine the prevalence of hypodontia in 662 Australian Defence Force recruits. Of the sampled population, 6.3 per cent exhibited some degree of hypodontia (third molar agenesis excluded). Previous studies produced similar results. Third molar agenesis occurred in 22.7 per cent of the sample which again is in agreement with other studies. There was no statistical difference between the sexes in third molar agenesis; however, there was a significant difference with upper second premolars. Females exhibited an extremely low incidence of absence of maxillary lateral incisors.

Apparatus for proton radiography

DOEpatents

Martin, Ronald L.

1976-01-01

An apparatus for effecting diagnostic proton radiography of patients in hospitals comprises a source of negative hydrogen ions, a synchrotron for accelerating the negative hydrogen ions to a predetermined energy, a plurality of stations for stripping extraction of a radiography beam of protons, means for sweeping the extracted beam to cover a target, and means for measuring the residual range, residual energy, or percentage transmission of protons that pass through the target. The combination of information identifying the position of the beam with information about particles traversing the subject and the back absorber is performed with the aid of a computer to provide a proton radiograph of the subject. In an alternate embodiment of the invention, a back absorber comprises a plurality of scintillators which are coupled to detectors.

Mars Exploration Rover Athena Panoramic Camera (Pancam) investigation

USGS Publications Warehouse

Bell, J.F.; Squyres, S. W.; Herkenhoff, K. E.; Maki, J.N.; Arneson, H.M.; Brown, D.; Collins, S.A.; Dingizian, A.; Elliot, S.T.; Hagerott, E.C.; Hayes, A.G.; Johnson, M.J.; Johnson, J. R.; Joseph, J.; Kinch, K.; Lemmon, M.T.; Morris, R.V.; Scherr, L.; Schwochert, M.; Shepard, M.K.; Smith, G.H.; Sohl-Dickstein, J. N.; Sullivan, R.J.; Sullivan, W.T.; Wadsworth, M.

2003-01-01

The Panoramic Camera (Pancam) investigation is part of the Athena science payload launched to Mars in 2003 on NASA's twin Mars Exploration Rover (MER) missions. The scientific goals of the Pancam investigation are to assess the high-resolution morphology, topography, and geologic context of each MER landing site, to obtain color images to constrain the mineralogic, photometric, and physical properties of surface materials, and to determine dust and aerosol opacity and physical properties from direct imaging of the Sun and sky. Pancam also provides mission support measurements for the rovers, including Sun-finding for rover navigation, hazard identification and digital terrain modeling to help guide long-term rover traverse decisions, high-resolution imaging to help guide the selection of in situ sampling targets, and acquisition of education and public outreach products. The Pancam optical, mechanical, and electronics design were optimized to achieve these science and mission support goals. Pancam is a multispectral, stereoscopic, panoramic imaging system consisting of two digital cameras mounted on a mast 1.5 m above the Martian surface. The mast allows Pancam to image the full 360?? in azimuth and ??90?? in elevation. Each Pancam camera utilizes a 1024 ?? 1024 active imaging area frame transfer CCD detector array. The Pancam optics have an effective focal length of 43 mm and a focal ratio f/20, yielding an instantaneous field of view of 0.27 mrad/pixel and a field of view of 16?? ?? 16??. Each rover's two Pancam "eyes" are separated by 30 cm and have a 1?? toe-in to provide adequate stereo parallax. Each eye also includes a small eight position filter wheel to allow surface mineralogic studies, multispectral sky imaging, and direct Sun imaging in the 400-1100 nm wavelength region. Pancam was designed and calibrated to operate within specifications on Mars at temperatures from -55?? to +5??C. An onboard calibration target and fiducial marks provide the capability

First Panoramic View From The Surface Of Mars

NASA Image and Video Library

1996-12-30

First panoramic view by NASA's Viking 1 from the surface of Mars. The out of focus spacecraft component toward left center is the housing for the Viking sample arm, which is not yet deployed. Parallel lines in the sky are an artifact and are not real features. However, the change of brightness from horizon towards zenith and towards the right (west) is accurately reflected in this picture, taken in late Martian afternoon. At the horizon to the left is a plateau-like prominence much brighter than the foreground material between the rocks. The horizon features are approximately three kilometers (1.8 miles) away. At left is a collection of fine-grained material reminiscent of sand dunes. The dark sinuous markings in left foreground are of unknown origin. Some unidentified shapes can be perceived on the hilly eminence at the horizon towards the right. A horizontal cloud stratum can be made out halfway from the horizon to the top of the picture. At left is seen the low gain antenna for receipt of commands from the Earth. The projections on or near the horizon may represent the rims distant impact craters. In right foreground are color charts for Lander camera calibration, a mirror for the Viking magnetic properties experiment and part of a grid on the top of the Lander body. At upper right is the high gain dish antenna for direct communication between landed spacecraft and Earth. Toward the right edge is an array of smooth fine-grained material which shows some hint of ripple structure and may be the beginning of a large dune field off to the right of the picture, which joins with dunes seen at the top left in this 300 degree panoramic view. Some of the rocks appear to be undercut on one side and partially buried by drifting sand on the other. http://photojournal.jpl.nasa.gov/catalog/PIA00383

Imaging of Rabbit VX-2 Hepatic Cancer by Cold and Thermal Neutron Radiography

NASA Astrophysics Data System (ADS)

Tsuchiya, Yoshinori; Matsubayashi, Masahito; Takeda, Tohoru; Lwin, Thet Thet; Wu, Jin; Yoneyama, Akio; Matsumura, Akira; Hori, Tomiei; Itai, Yuji

2003-11-01

Neutron radiography is based on differences in neutron mass attenuation coefficients among the elements and is a non-destructive imaging method. To investigate biomedical applications of neutron radiography, imaging of rabbit VX-2 liver cancer was performed using thermal and cold neutron radiography with a neutron imaging plate. Hepatic vessels and VX-2 tumor were clearly observed by neutron radiography, especially by cold neutron imaging. The image contrast of this modality was better than that of absorption-contrast X-ray radiography.

Radiography Student Participation in Professional Organizations.

PubMed

Michael, Kimberly; Tran, Xuan; Keller, Shelby; Sayles, Harlan; Custer, Tanya

2017-09-01

To gather data on educational program requirements for student membership in a state or national professional society, organization, or association. A 10-question online survey about student involvement in professional societies was emailed to 616 directors of Joint Review Committee on Education in Radiologic Technology (JRCERT)-accredited radiography programs. A total of 219 responses were received, for a 36% response rate. Of these, 89 respondents (41%) answered that their programs require students to join a professional organization. The society respondents most often required (70%) was a state radiography society. Sixty respondents (68%) answered that students join a society at the beginning of the radiography program (from matriculation to 3 months in). Of programs requiring student membership in professional societies, 42 (49%) reported that their students attend the state or national society annual conference; however, participation in activities at the conferences and in the society throughout the year is lower than conference attendance. Some directors stated that although their programs' policies do not allow membership mandates, they encourage students to become members, primarily so that they can access webinars and other educational materials or information related to the profession. Survey data showed that most JRCERT-accredited radiography programs support but do not require student membership in professional organizations. The data reveal that more programs have added those requirements in recent years. Increased student participation could be realized if programs mandated membership and supported it financially. ©2017 American Society of Radiologic Technologists.

The viability of ADVANTG deterministic method for synthetic radiography generation

NASA Astrophysics Data System (ADS)

Bingham, Andrew; Lee, Hyoung K.

2018-07-01

Fast simulation techniques to generate synthetic radiographic images of high resolution are helpful when new radiation imaging systems are designed. However, the standard stochastic approach requires lengthy run time with poorer statistics at higher resolution. The investigation of the viability of a deterministic approach to synthetic radiography image generation was explored. The aim was to analyze a computational time decrease over the stochastic method. ADVANTG was compared to MCNP in multiple scenarios including a small radiography system prototype, to simulate high resolution radiography images. By using ADVANTG deterministic code to simulate radiography images the computational time was found to decrease 10 to 13 times compared to the MCNP stochastic approach while retaining image quality.

Radiography Capabilities for Matter-Radiation Interactions in Extremes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walstrom, Peter Lowell; Garnett, Robert William; Chapman, Catherine A. B

The Matter-Radiation Interactions in Extremes (MaRIE) experimental facility will be used to discover and design the advanced materials needed to meet 21st century national security and energy security challenges. This new facility will provide the new tools scientists need to develop next-generation materials that will perform predictably and on-demand for currently unattainable lifetimes in extreme environments. The MaRIE facility is based on upgrades to the existing LANSCE 800-MeV proton linac and a new 12-GeV electron linac and associated X-ray FEL to provide simultaneous multiple probe beams, and new experimental areas. In addition to the high-energy photon probe beam, both electronmore » and proton radiography capabilities will be available at the MaRIE facility. Recently, detailed radiography system studies have been performed to develop conceptual layouts of high-magnification electron and proton radiography systems that can meet the experimental requirements for the expected first experiments to be performed at the facility. A description of the radiography systems, their performance requirements, and a proposed facility layout are presented.« less

Feline dental radiography and radiology: A primer.

PubMed

Niemiec, Brook A

2014-11-01

Information crucial to the diagnosis and treatment of feline oral diseases can be ascertained using dental radiography and the inclusion of this technology has been shown to be the best way to improve a dental practice. Becoming familar with the techniques required for dental radiology and radiography can, therefore, be greatly beneficial. Novices to dental radiography may need some time to adjust and become comfortable with the techniques. If using dental radiographic film, the generally recommended 'E' or 'F' speeds may be frustrating at first, due to their more specific exposure and image development requirements. Although interpreting dental radiographs is similar to interpreting a standard bony radiograph, there are pathologic states that are unique to the oral cavity and several normal anatomic structures that may mimic pathologic changes. Determining which teeth have been imaged also requires a firm knowledge of oral anatomy as well as the architecture of dental films/digital systems. This article draws on a range of dental radiography and radiology resources, and the benefit of the author's own experience, to review the basics of taking and interpreting intraoral dental radiographs. A simplified method for positioning the tubehead is explained and classic examples of some common oral pathologies are provided. © ISFM and AAFP 2014.

Second of three panoramic views of North Base as seen ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Second of three panoramic views of North Base as seen from top of Building 4500, Control Tower. View looks west (268°) at North Base complex. In foreground is taxiway, with Building 4456 (Fire House No. 4) at right. Building 4452 (Utility Vault) appears in extreme left foreground, with Building 4412 (Liquid Oxygen Repair Facility) and Building 4410 (Liquid Oxygen Storage) in extreme left background. In view over Building 4456 is the "loop" bound by Third, Fourth, A, and B Streets. Concrete slabs are all that remain of military housing constructed in the 1940s. - Edwards Air Force Base, North Base, North Base Road, Boron, Kern County, CA

Super-resolution fusion of complementary panoramic images based on cross-selection kernel regression interpolation.

PubMed

Chen, Lidong; Basu, Anup; Zhang, Maojun; Wang, Wei; Liu, Yu

2014-03-20

A complementary catadioptric imaging technique was proposed to solve the problem of low and nonuniform resolution in omnidirectional imaging. To enhance this research, our paper focuses on how to generate a high-resolution panoramic image from the captured omnidirectional image. To avoid the interference between the inner and outer images while fusing the two complementary views, a cross-selection kernel regression method is proposed. First, in view of the complementarity of sampling resolution in the tangential and radial directions between the inner and the outer images, respectively, the horizontal gradients in the expected panoramic image are estimated based on the scattered neighboring pixels mapped from the outer, while the vertical gradients are estimated using the inner image. Then, the size and shape of the regression kernel are adaptively steered based on the local gradients. Furthermore, the neighboring pixels in the next interpolation step of kernel regression are also selected based on the comparison between the horizontal and vertical gradients. In simulation and real-image experiments, the proposed method outperforms existing kernel regression methods and our previous wavelet-based fusion method in terms of both visual quality and objective evaluation.

A Comparison of Web Page and Slide/Tape for Instruction in Periapical and Panoramic Radiographic Anatomy.

ERIC Educational Resources Information Center

Ludlow, John B.; Platin, Enrique

2000-01-01

Compared self-guided slide/tape (ST) and Web page (WP) instruction in normal radiographic anatomy of periapical and panoramic images using objective test performance and subjective preferences of 74 freshman dental students. Test performance was not different between image types or presentation technologies, but students preferred WP for…

Application of segmented dental panoramic tomography among children: positive effect of continuing education in radiation protection.

PubMed

Pakbaznejad Esmaeili, Elmira; Waltimo-Sirén, Janna; Laatikainen, Tuula; Haukka, Jari; Ekholm, Marja

2016-05-23

Dental panoramic tomography is the most frequent examination among 7-12-year olds, according to the Radiation Safety and Nuclear Authority of Finland. At those ages, dental panoramic tomographs (DPTs) are mostly obtained for orthodontic reasons. Children's dose reduction by trimming the field size to the area of interest is important because of their high radiosensitivity. Yet, the majority of DPTs in this age group are still taken by using an adult programme and never by using a segmented programme. The purpose of the present study was to raise the awareness of dental staff with respect to children's radiation safety, to increase the application of segmented and child DPT programmes by further educating the whole dental team and to evaluate the outcome of the educational intervention. A five-step intervention programme, focusing on DPT field limitation possibilities, was carried out in community-based dental care as a part of mandatory continuing education in radiation protection. Application of segmented and child DPT programmes was thereafter prospectively followed up during a 1-year period and compared with our similar data from 2010 using a logistic regression analysis. Application of the child programme increased by 9% and the segmented programme by 2%, reaching statistical significance (odds ratios 1.68; 95% confidence interval 1.23-2.30; p-value < 0.001). The number of repeated exposures remained at an acceptable level. The segmented DPTs were most frequently taken from the maxillary lateral incisor-canine area. The educational intervention resulted in improvement of radiological practice in respect to radiation safety of children during dental panoramic tomography. Segmented and child DPT programmes can be applied successfully in dental practice for children.

Spherical rotation orientation indication for HEVC and JEM coding of 360 degree video

NASA Astrophysics Data System (ADS)

Boyce, Jill; Xu, Qian

2017-09-01

Omnidirectional (or "360 degree") video, representing a panoramic view of a spherical 360° ×180° scene, can be encoded using conventional video compression standards, once it has been projection mapped to a 2D rectangular format. Equirectangular projection format is currently used for mapping 360 degree video to a rectangular representation for coding using HEVC/JEM. However, video in the top and bottom regions of the image, corresponding to the "north pole" and "south pole" of the spherical representation, is significantly warped. We propose to perform spherical rotation of the input video prior to HEVC/JEM encoding in order to improve the coding efficiency, and to signal parameters in a supplemental enhancement information (SEI) message that describe the inverse rotation process recommended to be applied following HEVC/JEM decoding, prior to display. Experiment results show that up to 17.8% bitrate gain (using the WS-PSNR end-to-end metric) can be achieved for the Chairlift sequence using HM16.15 and 11.9% gain using JEM6.0, and an average gain of 2.9% for HM16.15 and 2.2% for JEM6.0.

Satisfaction of Search in Chest Radiography 2015.

PubMed

Berbaum, Kevin S; Krupinski, Elizabeth A; Schartz, Kevin M; Caldwell, Robert T; Madsen, Mark T; Hur, Seung; Laroia, Archana T; Thompson, Brad H; Mullan, Brian F; Franken, Edmund A

2015-11-01

Two decades have passed since the publication of laboratory studies of satisfaction of search (SOS) in chest radiography. Those studies were performed using film. The current investigation tests for SOS effects in computed radiography of the chest. Sixty-four chest computed radiographs half demonstrating various "test" abnormalities were read twice by 20 radiologists, once with and once without the addition of a simulated pulmonary nodule. Receiver-operating characteristic detection accuracy and decision thresholds were analyzed to study the effects of adding the nodule on detecting the test abnormalities. Results of previous studies were reanalyzed using similar modern techniques. In the present study, adding nodules did not influence detection accuracy for the other abnormalities (P = .93), but did induce a reluctance to report them (P < .001). Adding nodules did not affect inspection time (P = .58) so the reluctance to report was not associated with reduced search. Reanalysis revealed a similar decision threshold shift that had not been recognized in the early studies of SOS in chest radiography (P < .01) in addition to reduced detection accuracy (P < .01). The nature of SOS in chest radiography has changed, but it is not clear why. SOS may be changing as a function of changes in radiology education and practice. Copyright © 2015 AUR. Published by Elsevier Inc. All rights reserved.

Comprehensive optimization process of paranasal sinus radiography.

PubMed

Saarakkala, S; Nironen, K; Hermunen, H; Aarnio, J; Heikkinen, J O

2009-04-01

The optimization of radiological examinations is important in order to reduce unnecessary patient radiation exposure. To perform a comprehensive optimization process for paranasal sinus radiography at Mikkeli Central Hospital, Finland. Patients with suspicion of acute sinusitis were imaged with a Kodak computed radiography (CR) system (n=20) and with a Philips digital radiography (DR) system (n=30) using focus-detector distances (FDDs) of 110 cm, 150 cm, or 200 cm. Patients' radiation exposure was determined in terms of entrance surface dose and dose-area product. Furthermore, an anatomical phantom was used for the estimation of point doses inside the head. Clinical image quality was evaluated by an experienced radiologist, and physical image quality was evaluated from the digital radiography phantom. Patient doses were significantly lower and image quality better with the DR system compared to the CR system. The differences in patient dose and physical image quality were small with varying FDD. Clinical image quality of the DR system was lowest with FDD of 200 cm. Further, imaging with FDD of 150 cm was technically easier for the technologist to perform than with FDD of 110 cm. After optimization, it was recommended that the DR system with FDD of 150 cm should always be used at Mikkeli Central Hospital. We recommend this kind of comprehensive approach in all optimization processes of radiological examinations.

A comparison between conventional and digital radiography in root canal working length determination.

PubMed

Farida, Abesi; Maryam, Ehsani; Ali, Mirzapour; Ehsan, Moudi; Sajad, Yousefi; Soraya, Khafri

2013-01-01

Obtaining a correct working length is necessary for successful root canal treatment. The aim of this study was to compare conventional and digital radiography in measuring root canal working length. In this in vitro study 20 mesio buccal canal from maxillary first molars with moderate and severe curvature and 20 canal form anterior teeth with mild curvature were chosen and their working length were measured with number 15 k file (Maillefer, DENTSPLY, Germany). Then for each canal five radiographies were taken, three conventional radiographies using three methods of processing: Manual, automatic, and monobath solution; in addition to two other digital radiographies using CCD and PSP receptors. Two independent observers measured working length in each technique. Finally, the mean of working length in each group was compared with real working length using a paired T-test. Also a one-way ANOVA test was used for comparing the two groups. The level of statistical significance was P < 0.05. The results have shown that there was a high interobserver agreement on the measurements of the working length in conventional and digital radiography (P ≤ 0.001). Also there was no significant difference between conventional and digital radiography in measuring working length (P > 0.05). Therefore it was concluded that the accuracy of digital radiography is comparable with conventional radiography in measuring working length, so considering the advantages of the digital radiography, it can be used for working length determination.

Rank distributions: A panoramic macroscopic outlook

NASA Astrophysics Data System (ADS)

Eliazar, Iddo I.; Cohen, Morrel H.

2014-01-01

This paper presents a panoramic macroscopic outlook of rank distributions. We establish a general framework for the analysis of rank distributions, which classifies them into five macroscopic "socioeconomic" states: monarchy, oligarchy-feudalism, criticality, socialism-capitalism, and communism. Oligarchy-feudalism is shown to be characterized by discrete macroscopic rank distributions, and socialism-capitalism is shown to be characterized by continuous macroscopic size distributions. Criticality is a transition state between oligarchy-feudalism and socialism-capitalism, which can manifest allometric scaling with multifractal spectra. Monarchy and communism are extreme forms of oligarchy-feudalism and socialism-capitalism, respectively, in which the intrinsic randomness vanishes. The general framework is applied to three different models of rank distributions—top-down, bottom-up, and global—and unveils each model's macroscopic universality and versatility. The global model yields a macroscopic classification of the generalized Zipf law, an omnipresent form of rank distributions observed across the sciences. An amalgamation of the three models establishes a universal rank-distribution explanation for the macroscopic emergence of a prevalent class of continuous size distributions, ones governed by unimodal densities with both Pareto and inverse-Pareto power-law tails.

Rank distributions: a panoramic macroscopic outlook.

PubMed

Eliazar, Iddo I; Cohen, Morrel H

2014-01-01

This paper presents a panoramic macroscopic outlook of rank distributions. We establish a general framework for the analysis of rank distributions, which classifies them into five macroscopic "socioeconomic" states: monarchy, oligarchy-feudalism, criticality, socialism-capitalism, and communism. Oligarchy-feudalism is shown to be characterized by discrete macroscopic rank distributions, and socialism-capitalism is shown to be characterized by continuous macroscopic size distributions. Criticality is a transition state between oligarchy-feudalism and socialism-capitalism, which can manifest allometric scaling with multifractal spectra. Monarchy and communism are extreme forms of oligarchy-feudalism and socialism-capitalism, respectively, in which the intrinsic randomness vanishes. The general framework is applied to three different models of rank distributions-top-down, bottom-up, and global-and unveils each model's macroscopic universality and versatility. The global model yields a macroscopic classification of the generalized Zipf law, an omnipresent form of rank distributions observed across the sciences. An amalgamation of the three models establishes a universal rank-distribution explanation for the macroscopic emergence of a prevalent class of continuous size distributions, ones governed by unimodal densities with both Pareto and inverse-Pareto power-law tails.

Unified Database for Rejected Image Analysis Across Multiple Vendors in Radiography.

PubMed

Little, Kevin J; Reiser, Ingrid; Liu, Lili; Kinsey, Tiffany; Sánchez, Adrian A; Haas, Kateland; Mallory, Florence; Froman, Carmen; Lu, Zheng Feng

2017-02-01

Reject rate analysis has been part of radiography departments' quality control since the days of screen-film radiography. In the era of digital radiography, one might expect that reject rate analysis is easily facilitated because of readily available information produced by the modality during the examination procedure. Unfortunately, this is not always the case. The lack of an industry standard and the wide variety of system log entries and formats have made it difficult to implement a robust multivendor reject analysis program, and logs do not always include all relevant information. The increased use of digital detectors exacerbates this problem because of higher reject rates associated with digital radiography compared with computed radiography. In this article, the authors report on the development of a unified database for vendor-neutral reject analysis across multiple sites within an academic institution and share their experience from a team-based approach to reduce reject rates. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Digital radiography: are the manufacturers' settings too high? Optimisation of the Kodak digital radiography system with aid of the computed radiography dose index.

PubMed

Peters, Sinead E; Brennan, Patrick C

2002-09-01

Manufacturers offer exposure indices as a safeguard against overexposure in computed radiography, but the basis for recommended values is unclear. This study establishes an optimum exposure index to be used as a guideline for a specific CR system to minimise radiation exposures for computed mobile chest radiography, and compares this with manufacturer guidelines and current practice. An anthropomorphic phantom was employed to establish the minimum milliamperes consistent with acceptable image quality for mobile chest radiography images. This was found to be 2 mAs. Consecutively, 10 patients were exposed with this optimised milliampere value and 10 patients were exposed with the 3.2 mAs routinely used in the department of the study. Image quality was objectively assessed using anatomical criteria. Retrospective analyses of 717 exposure indices recorded over 2 months from mobile chest examinations were performed. The optimised milliampere value provided a significant reduction of the average exposure index from 1840 to 1570 ( p<0.0001). This new "optimum" exposure index is substantially lower than manufacturer guidelines of 2000 and significantly lower than exposure indices from the retrospective study (1890). Retrospective data showed a significant increase in exposure indices if the examination was performed out of hours. The data provided by this study emphasise the need for clinicians and personnel to consider establishing their own optimum exposure indices for digital investigations rather than simply accepting manufacturers' guidelines. Such an approach, along with regular monitoring of indices, may result in a substantial reduction in patient exposure.

Ulnar Rotation Osteotomy for Congenital Radial Head Dislocation.

PubMed

Liu, Ruiyu; Miao, Wusheng; Mu, Mingchao; Wu, Ge; Qu, Jining; Wu, Yongtao

2015-09-01

To evaluate an ulnar rotation osteotomy for congenital anterior dislocation of the radial head. Nine patients (5 boys and 4 girls aged 6 to 13 years) with congenital anterior dislocation of the radial head were treated with ulnar rotation osteotomy. Magnetic resonance imaging of the elbow showed the proximal radioulnar joint on the anterior-lateral side of the ulna rather than on the lateral side in patients with congenital anterior dislocation of the radial head. On the basis of this finding, we performed an osteotomy on the ulna and laterally rotated the proximal radioulnar joint achieving radial head reduction and restoring the anatomical relationship between the radial head and the capitellum. Clinical and radiographical evaluation of the elbow was performed before surgery and at postoperative follow-up. All patients were followed for 13 to 45 months after surgery. Elbow radiography showed that the radiocapitellar joint was reduced in all patients at the last follow-up visit and that the carrying angle was decreased relative to that in the preoperative condition. Elbow stability and the range of elbow flexion motion were improved at the last follow-up. We did not observe ulnar osteotomy site nonunion or elbow osteoarthritis in these patients. Furthermore, radial head dislocation did not recur. At early follow-up, ulnar rotation osteotomy was a safe and effective method for the treatment of congenital anterior dislocation of the radial head. Therapeutic IV. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Using Google Streetview Panoramic Imagery for Geoscience Education

NASA Astrophysics Data System (ADS)

De Paor, D. G.; Dordevic, M. M.

2014-12-01

Google Streetview is a feature of Google Maps and Google Earth that allows viewers to switch from map or satellite view to 360° panoramic imagery recorded close to the ground. Most panoramas are recorded by Google engineers using special cameras mounted on the roofs of cars. Bicycles, snowmobiles, and boats have also been used and sometimes the camera has been mounted on a backpack for off-road use by hikers and skiers or attached to scuba-diving gear for "Underwater Streetview (sic)." Streetview panoramas are linked together so that the viewer can change viewpoint by clicking forward and reverse buttons. They therefore create a 4-D touring effect. As part of the GEODE project ("Google Earth for Onsite and Distance Education"), we are experimenting with the use of Streetview imagery for geoscience education. Our web-based test application allows instructors to select locations for students to study. Students are presented with a set of questions or tasks that they must address by studying the panoramic imagery. Questions include identification of rock types, structures such as faults, and general geological setting. The student view is locked into Streetview mode until they submit their answers, whereupon the map and satellite views become available, allowing students to zoom out and verify their location on Earth. Student learning is scaffolded by automatic computerized feedback. There are lots of existing Streetview panoramas with rich geological content. Additionally, instructors and members of the general public can create panoramas, including 360° Photo Spheres, by stitching images taken with their mobiles devices and submitting them to Google for evaluation and hosting. A multi-thousand-dollar, multi-directional camera and mount can be purchased from DIY-streetview.com. This allows power users to generate their own high-resolution panoramas. A cheaper, 360° video camera is soon to be released according to geonaute.com. Thus there are opportunities for

First Panoramic View From The Surface Of Mars

NASA Technical Reports Server (NTRS)

1976-01-01

First panoramic view by Viking 1 from the surface of Mars. (Top): The out-of-focus spacecraft component toward left center is the housing for the Viking sample arm, which is not yet deployed. Parallel lines in the sky are an artifact and are not real features. However, the change of brightness from horizon towards zenith and towards the right (west) is accurately reflected in this picture, taken in late Martian afternoon. At the horizon to the left is a plateau-like prominence much brighter than the foreground material between the rocks. The horizon features are approximately three kilometers (1.8 miles) away. At left is a collection of fine-grained material reminiscent of sand dunes. The dark sinuous markings in left foreground are of unknown origin. Some unidentified shapes can be perceived on the hilly eminence at the horizon towards the right. Patches of bright sand can be discerned among the rocks and boulders in middle distance. In right fore-ground are two peculiarly shaped rocks which may possibly be ventifacts produced by wind abrasion on Mars. A horizontal cloud stratum can be made out halfway from the horizon to the top of the picture. (Bottom): At left is seen the low gain antenna for receipt of commands from the Earth. The projections on or near the horizon may represent the rims distant impact craters. In right foreground are color charts for Lander camera calibration, a mirror for the Viking magnetic properties experiment and part of a grid on the top of the Lander body. At upper right is the high-gain dish antenna for direct communication between landed space-craft and Earth. Toward the right edge is an array of smooth fine-grained material which shows some hint of ripple structure and may be the beginning of a large dune field off to the right of the picture, which joins with dunes seen at the top left in this 300 panoramic view. Some of the rocks appear to be undercut on one side and partially buried by drifting sand on the other.

First Panoramic View From The Surface Of Mars

NASA Image and Video Library

1996-12-30

First panoramic view by Viking 1 from the surface of Mars. (Top): The out-of-focus spacecraft component toward left center is the housing for the Viking sample arm, which is not yet deployed. Parallel lines in the sky are an artifact and are not real features. However, the change of brightness from horizon towards zenith and towards the right (west) is accurately reflected in this picture, taken in late Martian afternoon. At the horizon to the left is a plateau-like prominence much brighter than the foreground material between the rocks. The horizon features are approximately three kilometers (1.8 miles) away. At left is a collection of fine-grained material reminiscent of sand dunes. The dark sinuous markings in left foreground are of unknown origin. Some unidentified shapes can be perceived on the hilly eminence at the horizon towards the right. Patches of bright sand can be discerned among the rocks and boulders in middle distance. In right fore-ground are two peculiarly shaped rocks which may possibly be ventifacts produced by wind abrasion on Mars. A horizontal cloud stratum can be made out halfway from the horizon to the top of the picture. (Bottom): At left is seen the low gain antenna for receipt of commands from the Earth. The projections on or near the horizon may represent the rims distant impact craters. In right foreground are color charts for Lander camera calibration, a mirror for the Viking magnetic properties experiment and part of a grid on the top of the Lander body. At upper right is the high-gain dish antenna for direct communication between landed space-craft and Earth. Toward the right edge is an array of smooth fine-grained material which shows some hint of ripple structure and may be the beginning of a large dune field off to the right of the picture, which joins with dunes seen at the top left in this 300 panoramic view. Some of the rocks appear to be undercut on one side and partially buried by drifting sand on the other. http

The shell game: a panoramic view of Fornax

NASA Astrophysics Data System (ADS)

Bate, N. F.; McMonigal, B.; Lewis, G. F.; Irwin, M. J.; Gonzalez-Solares, E.; Shanks, T.; Metcalfe, N.

2015-10-01

We present a panoramic study of the Fornax dwarf spheroidal galaxy, using data obtained as part of the VLT Survey Telescope (VST) ATLAS Survey. The data presented here - a subset of the full survey - uniformly cover a region of 25 deg2 centred on the galaxy, in g, r and i bands. This large area coverage reveals two key differences to previous studies of Fornax. First, data extending beyond the nominal tidal radius of the dwarf highlight the presence of a second distinct red giant branch population. This bluer red giant branch appears to be co-eval with the horizontal branch population. Secondly, a shell structure located approximately 1.4° from the centre of Fornax is shown to be a mis-identified background overdensity of galaxies. This last result casts further doubt on the hypothesis that Fornax underwent a gas-rich merger in its relatively recent past.

Computed radiography imaging plates and associated methods of manufacture

DOEpatents

Henry, Nathaniel F.; Moses, Alex K.

2015-08-18

Computed radiography imaging plates incorporating an intensifying material that is coupled to or intermixed with the phosphor layer, allowing electrons and/or low energy x-rays to impart their energy on the phosphor layer, while decreasing internal scattering and increasing resolution. The radiation needed to perform radiography can also be reduced as a result.

Radiation doses in examination of lower third molars with computed tomography and conventional radiography.

PubMed

Ohman, A; Kull, L; Andersson, J; Flygare, L

2008-12-01

To measure organ doses and calculate effective doses for pre-operative radiographic examination of lower third molars with CT and conventional radiography (CR). Measurements of organ doses were made on an anthropomorphic head phantom with lithium fluoride thermoluminescent dosemeters. The dosemeters were placed in regions corresponding to parotid and submandibular glands, mandibular bone, thyroid gland, skin, eye lenses and brain. The organ doses were used for the calculation of effective doses according to proposed International Commission on Radiological Protection 2005 guidelines. For the CT examination, a Siemens Somatom Plus 4 Volume Zoom was used and exposure factors were set to 120 kV and 100 mAs. For conventional radiographs, a Scanora unit was used and panoramic, posteroanterior, stereographic (scanogram) and conventional spiral tomographic views were exposed. The effective doses were 0.25 mSv, 0.060 mSv and 0.093 mSv for CT, CR without conventional tomography and CR with conventional spiral tomography, respectively. The effective dose is low when CT examination with exposure factors optimized for the examination of bone structures is performed. However, the dose is still about four times as high as for CR without tomography. CT should therefore not be a standard method for the examination of lower third molars. In cases where there is a close relationship between the tooth and the inferior alveolar nerve the advantages of true sectional imaging, such as CT, outweighs the higher effective dose and is recommended. Further reduction in the dose is feasible with further optimization of examination protocols and the development of newer techniques.

Application of segmented dental panoramic tomography among children: positive effect of continuing education in radiation protection

PubMed Central

Waltimo-Sirén, Janna; Laatikainen, Tuula; Haukka, Jari; Ekholm, Marja

2016-01-01

Objectives: Dental panoramic tomography is the most frequent examination among 7–12-year olds, according to the Radiation Safety and Nuclear Authority of Finland. At those ages, dental panoramic tomographs (DPTs) are mostly obtained for orthodontic reasons. Children's dose reduction by trimming the field size to the area of interest is important because of their high radiosensitivity. Yet, the majority of DPTs in this age group are still taken by using an adult programme and never by using a segmented programme. The purpose of the present study was to raise the awareness of dental staff with respect to children's radiation safety, to increase the application of segmented and child DPT programmes by further educating the whole dental team and to evaluate the outcome of the educational intervention. Methods: A five-step intervention programme, focusing on DPT field limitation possibilities, was carried out in community-based dental care as a part of mandatory continuing education in radiation protection. Application of segmented and child DPT programmes was thereafter prospectively followed up during a 1-year period and compared with our similar data from 2010 using a logistic regression analysis. Results: Application of the child programme increased by 9% and the segmented programme by 2%, reaching statistical significance (odds ratios 1.68; 95% confidence interval 1.23–2.30; p-value < 0.001). The number of repeated exposures remained at an acceptable level. The segmented DPTs were most frequently taken from the maxillary lateral incisor–canine area. Conclusions: The educational intervention resulted in improvement of radiological practice in respect to radiation safety of children during dental panoramic tomography. Segmented and child DPT programmes can be applied successfully in dental practice for children. PMID:27142159

10 CFR 34.42 - Radiation Safety Officer for industrial radiography.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 1 2012-01-01 2012-01-01 false Radiation Safety Officer for industrial radiography. 34.42 Section 34.42 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Radiation Safety Requirements § 34.42...

10 CFR 34.42 - Radiation Safety Officer for industrial radiography.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Radiation Safety Officer for industrial radiography. 34.42 Section 34.42 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Radiation Safety Requirements § 34.42...

10 CFR 34.42 - Radiation Safety Officer for industrial radiography.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 1 2013-01-01 2013-01-01 false Radiation Safety Officer for industrial radiography. 34.42 Section 34.42 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Radiation Safety Requirements § 34.42...

10 CFR 34.42 - Radiation Safety Officer for industrial radiography.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 1 2011-01-01 2011-01-01 false Radiation Safety Officer for industrial radiography. 34.42 Section 34.42 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Radiation Safety Requirements § 34.42...

10 CFR 34.42 - Radiation Safety Officer for industrial radiography.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 1 2014-01-01 2014-01-01 false Radiation Safety Officer for industrial radiography. 34.42 Section 34.42 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Radiation Safety Requirements § 34.42...

10 CFR 34.20 - Performance requirements for industrial radiography equipment.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 1 2014-01-01 2014-01-01 false Performance requirements for industrial radiography equipment. 34.20 Section 34.20 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Equipment § 34.20 Performance...

10 CFR 34.20 - Performance requirements for industrial radiography equipment.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 1 2012-01-01 2012-01-01 false Performance requirements for industrial radiography equipment. 34.20 Section 34.20 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Equipment § 34.20 Performance...

10 CFR 34.20 - Performance requirements for industrial radiography equipment.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Performance requirements for industrial radiography equipment. 34.20 Section 34.20 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Equipment § 34.20 Performance...

10 CFR 34.20 - Performance requirements for industrial radiography equipment.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 1 2011-01-01 2011-01-01 false Performance requirements for industrial radiography equipment. 34.20 Section 34.20 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Equipment § 34.20 Performance...

10 CFR 34.20 - Performance requirements for industrial radiography equipment.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 1 2013-01-01 2013-01-01 false Performance requirements for industrial radiography equipment. 34.20 Section 34.20 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Equipment § 34.20 Performance...

Low-Cost Optical Mapping Systems for Panoramic Imaging of Complex Arrhythmias and Drug-Action in Translational Heart Models.

PubMed

Lee, Peter; Calvo, Conrado J; Alfonso-Almazán, José M; Quintanilla, Jorge G; Chorro, Francisco J; Yan, Ping; Loew, Leslie M; Filgueiras-Rama, David; Millet, José

2017-02-27

Panoramic optical mapping is the primary method for imaging electrophysiological activity from the entire outer surface of Langendorff-perfused hearts. To date, it is the only method of simultaneously measuring multiple key electrophysiological parameters, such as transmembrane voltage and intracellular free calcium, at high spatial and temporal resolution. Despite the impact it has already had on the fields of cardiac arrhythmias and whole-heart computational modeling, present-day system designs precludes its adoption by the broader cardiovascular research community because of their high costs. Taking advantage of recent technological advances, we developed and validated low-cost optical mapping systems for panoramic imaging using Langendorff-perfused pig hearts, a clinically-relevant model in basic research and bioengineering. By significantly lowering financial thresholds, this powerful cardiac electrophysiology imaging modality may gain wider use in research and, even, teaching laboratories, which we substantiated using the lower-cost Langendorff-perfused rabbit heart model.

Low-Cost Optical Mapping Systems for Panoramic Imaging of Complex Arrhythmias and Drug-Action in Translational Heart Models

NASA Astrophysics Data System (ADS)

Lee, Peter; Calvo, Conrado J.; Alfonso-Almazán, José M.; Quintanilla, Jorge G.; Chorro, Francisco J.; Yan, Ping; Loew, Leslie M.; Filgueiras-Rama, David; Millet, José

2017-02-01

Panoramic optical mapping is the primary method for imaging electrophysiological activity from the entire outer surface of Langendorff-perfused hearts. To date, it is the only method of simultaneously measuring multiple key electrophysiological parameters, such as transmembrane voltage and intracellular free calcium, at high spatial and temporal resolution. Despite the impact it has already had on the fields of cardiac arrhythmias and whole-heart computational modeling, present-day system designs precludes its adoption by the broader cardiovascular research community because of their high costs. Taking advantage of recent technological advances, we developed and validated low-cost optical mapping systems for panoramic imaging using Langendorff-perfused pig hearts, a clinically-relevant model in basic research and bioengineering. By significantly lowering financial thresholds, this powerful cardiac electrophysiology imaging modality may gain wider use in research and, even, teaching laboratories, which we substantiated using the lower-cost Langendorff-perfused rabbit heart model.

A benchmark for comparison of dental radiography analysis algorithms.

PubMed

Wang, Ching-Wei; Huang, Cheng-Ta; Lee, Jia-Hong; Li, Chung-Hsing; Chang, Sheng-Wei; Siao, Ming-Jhih; Lai, Tat-Ming; Ibragimov, Bulat; Vrtovec, Tomaž; Ronneberger, Olaf; Fischer, Philipp; Cootes, Tim F; Lindner, Claudia

2016-07-01

Dental radiography plays an important role in clinical diagnosis, treatment and surgery. In recent years, efforts have been made on developing computerized dental X-ray image analysis systems for clinical usages. A novel framework for objective evaluation of automatic dental radiography analysis algorithms has been established under the auspices of the IEEE International Symposium on Biomedical Imaging 2015 Bitewing Radiography Caries Detection Challenge and Cephalometric X-ray Image Analysis Challenge. In this article, we present the datasets, methods and results of the challenge and lay down the principles for future uses of this benchmark. The main contributions of the challenge include the creation of the dental anatomy data repository of bitewing radiographs, the creation of the anatomical abnormality classification data repository of cephalometric radiographs, and the definition of objective quantitative evaluation for comparison and ranking of the algorithms. With this benchmark, seven automatic methods for analysing cephalometric X-ray image and two automatic methods for detecting bitewing radiography caries have been compared, and detailed quantitative evaluation results are presented in this paper. Based on the quantitative evaluation results, we believe automatic dental radiography analysis is still a challenging and unsolved problem. The datasets and the evaluation software will be made available to the research community, further encouraging future developments in this field. (http://www-o.ntust.edu.tw/~cweiwang/ISBI2015/). Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

The quality assessment of radial and tangential neutron radiography beamlines of TRR

NASA Astrophysics Data System (ADS)

Choopan Dastjerdi, M. H.; Movafeghi, A.; Khalafi, H.; Kasesaz, Y.

2017-07-01

To achieve a quality neutron radiographic image in a relatively short exposure time, the neutron radiography beam must be of good quality and relatively high neutron flux. Characterization of a neutron radiography beam, such as determination of the image quality and the neutron flux, is vital for producing quality radiographic images and also provides a means to compare the quality of different neutron radiography facilities. This paper provides a characterization of the radial and tangential neutron radiography beamlines at the Tehran research reactor. This work includes determination of the facilities category according to the American Society for Testing and Materials (ASTM) standards, and also uses the gold foils to determine the neutron beam flux. The radial neutron beam is a Category I neutron radiography facility, the highest possible quality level according to the ASTM. The tangential beam is a Category IV neutron radiography facility. Gold foil activation experiments show that the measured neutron flux for radial beamline with length-to-diameter ratio (L/D) =150 is 6.1× 106 n cm-2 s-1 and for tangential beamline with (L/D)=115 is 2.4× 104 n cm-2 s-1.

Is radiography justified for the evaluation of patients presenting with cervical spine trauma?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Theocharopoulos, Nicholas; Chatzakis, Georgios; Damilakis, John

2009-10-15

Conventional radiography has been for decades the standard method of evaluation for cervical spine trauma patients. However, currently available helical multidetector CT scanners allow multiplanar reconstruction of images, leading to increased diagnostic accuracy. The purpose of this study was to determine the relative benefit/risk ratio between cervical spine CT and cervical spine radiography and between cervical spine CT and cervical spine radiography, followed by CT as an adjunct for positive findings. A decision analysis model for the determination of the optimum imaging technique was developed. The sensitivity and specificity of CT and radiography were obtained by dedicated meta-analysis. Lifetime attributablemore » risk of mortal cancer from CT and radiography was calculated using updated organ-specific risk coefficients and organ-absorbed doses. Patient organ doses from radiography were calculated using Monte Carlo techniques, simulated exposures performed on an anthropomorphic phantom, and thermoluminescence dosimetry. A prospective patient study was performed regarding helical CT scans of the cervical spine. Patient doses were calculated based on the dose-length-product values and Monte Carlo-based CT dosimetry software program. Three groups of patient risk for cervical spine fracture were incorporated in the decision model on the basis of hypothetical trauma mechanism and clinical findings. Radiation effects were assessed separately for males and females for four age groups (20, 40, 60, and 80 yr old). Effective dose from radiography amounts to 0.050 mSv and from a typical CT scan to 3.8 mSv. The use of CT in a hypothetical cohort of 10{sup 6} patients prevents approximately 130 incidents of paralysis in the low risk group (a priori fracture probability of 0.5%), 500 in the moderate risk group (a priori fracture probability of 2%), and 5100 in the high risk group (a priori fracture probability of 20%). The expense of this CT-based prevention is 15

Utilization and costs of lumbar and full spine radiography by Ontario chiropractors from 1994 to 2001.

PubMed

Ammendolia, Carlo; Côté, Pierre; Hogg-Johnson, Sheilah; Bombardier, Claire

2009-07-01

In Ontario, chiropractors see one-third of patients who seek care for low back pain. Previous studies suggest that chiropractors have high utilization rates of lumbar and full spine radiography. There has been a proliferation of evidence-based guidelines recommending that plain film radiography be used only to assess high-risk patients with low back pain. Evidence for the use of full spine radiography, except for the evaluation of scoliosis is lacking. It is uncertain what impact the growing evidence against their use has had on radiography utilization by Ontario chiropractors. To describe the annual costs and use of lumbar and full spine plain film radiography among Ontario chiropractors between 1994 and 2001. Time-trend analysis of radiography utilization by Ontario chiropractors. Chiropractic claims data submitted to the Ontario Health Insurance Plan or the Workplace Safety & Insurance Board from 1994/1995 to 2000/2001. Change in the annual cost and proportion of claimants receiving lumbar and full spine radiography. Time-trend analysis of chiropractic claims submitted to the Ontario Health Insurance Plan (OHIP) or Workplace Safety & Insurance Board (WSIB) from 1994/1995 to 2000/2001 fiscal years. During the 7-year period, the proportion of OHIP claimants receiving lumbar spine radiography decreased from 4.54% to 3.25% and for full spine radiography from 3.87% to 3.04%. For WSIB claimants, lumbar spine radiography deceased from 6.49% to 3.30% of claimants and full spine radiography from 1.51% to 0.94%. OHIP payments for lumbar spine radiography decreased 12.7% to $562,944, whereas full spine radiography payments decreased 5.3% to $1,071,408. WSIB lumbar and full spine radiography payments decreased 44.2% and 34.3% to $31,202 and $11,713 respectively. Claims data from the two largest third-party payers of chiropractic services in Ontario, suggest that lumbar and full spine radiography, and their associated costs decreased steadily between 1994 and 2001.

In Situ Real-Time Radiographic Study of Thin Film Formation Inside Rotating Hollow Spheres

DOE PAGES

Braun, Tom; Walton, Christopher C.; Dawedeit, Christoph; ...

2016-02-03

The hollow spheres with uniform coatings on the inner surface have applications in optical devices, time- or site-controlled drug release, heat storage devices, and target fabrication for inertial confinement fusion experiments. The fabrication of uniform coatings, which is often critical for the application performance, requires precise understanding and control over the coating process and its parameters. We report on in situ real-time radiography experiments that provide critical spatiotemporal information about the distribution of fluids inside hollow spheres during uniaxial rotation. Furthermore, image analysis and computer fluid dynamics simulations were used to explore the effect of liquid viscosity and rotational velocitymore » on the film uniformity. The data were then used to demonstrate the fabrication of uniform sol–gel chemistry derived porous polymer films inside 2 mm inner diameter diamond shells.« less

In Situ Real-Time Radiographic Study of Thin Film Formation Inside Rotating Hollow Spheres

DOE Office of Scientific and Technical Information (OSTI.GOV)

Braun, Tom; Walton, Christopher C.; Dawedeit, Christoph

2016-02-03

Hollow spheres with uniform coatings on the inner surface have applications in optical devices, time- or site controlled drug release, heat storage devices, and target fabrication for inertial confinement fusion experiments. The fabrication of uniform coatings, which is often critical for the application performance, requires precise understanding and control over the coating process and its parameters. Here, we report on in-situ real-time radiography experiments that provide critical spatio-temporal information about the distribution of fluids inside hollow spheres during uniaxial rotation. Image analysis and computer fluid dynamics simulations were used to explore the effect of liquid viscosity and rotational velocity onmore » the film uniformity. The data were then used to demonstrate the fabrication of uniform sol-gel chemistry derived porous polymer films inside 2mm inner diameter diamond shells.« less

Digital Radiography

NASA Technical Reports Server (NTRS)

1986-01-01

System One, a digital radiography system, incorporates a reusable image medium (RIM) which retains an image. No film is needed; the RIM is read with a laser scanner, and the information is used to produce a digital image on an image processor. The image is stored on an optical disc. System allows the radiologist to "dial away" unwanted images to compare views on three screens. It is compatible with existing equipment and cost efficient. It was commercialized by a Stanford researcher from energy selective technology developed under a NASA grant.

Dose audit for patients undergoing two common radiography examinations with digital radiology systems.

PubMed

İnal, Tolga; Ataç, Gökçe

2014-01-01

We aimed to determine the radiation doses delivered to patients undergoing general examinations using computed or digital radiography systems in Turkey. Radiographs of 20 patients undergoing posteroanterior chest X-ray and of 20 patients undergoing anteroposterior kidney-ureter-bladder radiography were evaluated in five X-ray rooms at four local hospitals in the Ankara region. Currently, almost all radiology departments in Turkey have switched from conventional radiography systems to computed radiography or digital radiography systems. Patient dose was measured for both systems. The results were compared with published diagnostic reference levels (DRLs) from the European Union and International Atomic Energy Agency. The average entrance surface doses (ESDs) for chest examinations exceeded established international DRLs at two of the X-ray rooms in a hospital with computed radiography. All of the other ESD measurements were approximately equal to or below the DRLs for both examinations in all of the remaining hospitals. Improper adjustment of the exposure parameters, uncalibrated automatic exposure control systems, and failure of the technologists to choose exposure parameters properly were problems we noticed during the study. This study is an initial attempt at establishing local DRL values for digital radiography systems, and will provide a benchmark so that the authorities can establish reference dose levels for diagnostic radiology in Turkey.

Optimisation and establishment of diagnostic reference levels in paediatric plain radiography

NASA Astrophysics Data System (ADS)

Paulo, Graciano do Nascimento Nobre

Purpose: This study aimed to propose Diagnostic Reference Levels (DRLs) in paediatric plain radiography and to optimise the most frequent paediatric plain radiography examinations in Portugal following an analysis and evaluation of current practice. Methods and materials: Anthropometric data (weight, patient height and thickness of the irradiated anatomy) was collected from 9,935 patients referred for a radiography procedure to one of the three dedicated paediatric hospitals in Portugal. National DRLs were calculated for the three most frequent X-ray procedures at the three hospitals: chest AP/PA projection; abdomen AP projection; pelvis AP projection. Exposure factors and patient dose were collected prospectively at the clinical sites. In order to analyse the relationship between exposure factors, the use of technical features and dose, experimental tests were made using two anthropomorphic phantoms: a) CIRSTM ATOM model 705; height: 110cm, weight: 19kg and b) Kyoto kagakuTM model PBU-60; height: 165cm, weight: 50kg. After phantom data collection, an objective image analysis was performed by analysing the variation of the mean value of the standard deviation, measured with OsiriX software (Pixmeo, Switzerland). After proposing new exposure criteria, a Visual Grading Characteristic image quality evaluation was performed blindly by four paediatric radiologists, each with a minimum of 10 years of professional experience, using anatomical criteria scoring. Results: DRLs by patient weight groups have been established for the first time. ESAKP75 DRLs for both patient age and weight groups were also obtained and are described in the thesis. Significant dose reduction was achieved through the implementation of an optimisation programme: an average reduction of 41% and 18% on KAPP75 and ESAKP75, respectively for chest plain radiography; an average reduction of 58% and 53% on KAPP75 and ESAKP75, respectively for abdomen plain radiography; and an average reduction of 47% and

Panoramic images of white and black post-menopausal females evidencing carotid calcifications are at high risk of comorbid osteopenia of the femoral neck

PubMed Central

Friedlander, AH; Chang, TI; Aghazadehsanai, N; Berenji, GR; Harada, ND; Garrett, NR

2013-01-01

Objectives: Femoral neck fractures in older females resulting from decreased bone mineral density (BMD; osteopenia) are associated with increased morbidity and mortality. Bone mineralization inhibition is probably controlled by proteins which also foster vascular calcification. Therefore, we evaluated the relationship between calcified carotid artery plaque (CCAP) on panoramic images and BMD on dual energy X-ray absorptiometry (DXA) bone scans. Methods: Images and hospital records identified by dentists defined two study groups (20 white females and 24 black females) having CCAP and an incidentally obtained bone scan. Ethnically matched (age±7 years, body mass index ±3 units) control groups with panoramic images devoid of CCAP and accompanying DXA scan were likewise constituted. A physician determined the BMD on the DXA. Results: Females with CCAP had significantly (p = 0.03) poorer BMD at the femoral neck than those without CCAP. Although mean femoral neck BMD was significantly lower (p = 0.009) for white than for black females, there was no significant interaction between race and CCAP (p = 0.80). Conclusion: We observed a significant inverse association between the CCAP on panoramic images and femoral neck BMD in post-menopausal white females. PMID:23571481

Panoramic images of white and black post-menopausal females evidencing carotid calcifications are at high risk of comorbid osteopenia of the femoral neck.

PubMed

Friedlander, A H; Chang, T I; Aghazadehsanai, N; Berenji, G R; Harada, N D; Garrett, N R

2013-01-01

Femoral neck fractures in older females resulting from decreased bone mineral density (BMD; osteopenia) are associated with increased morbidity and mortality. Bone mineralization inhibition is probably controlled by proteins which also foster vascular calcification. Therefore, we evaluated the relationship between calcified carotid artery plaque (CCAP) on panoramic images and BMD on dual energy X-ray absorptiometry (DXA) bone scans. Images and hospital records identified by dentists defined two study groups (20 white females and 24 black females) having CCAP and an incidentally obtained bone scan. Ethnically matched (age±7 years, body mass index ±3 units) control groups with panoramic images devoid of CCAP and accompanying DXA scan were likewise constituted. A physician determined the BMD on the DXA. Females with CCAP had significantly (p = 0.03) poorer BMD at the femoral neck than those without CCAP. Although mean femoral neck BMD was significantly lower (p = 0.009) for white than for black females, there was no significant interaction between race and CCAP (p = 0.80). We observed a significant inverse association between the CCAP on panoramic images and femoral neck BMD in post-menopausal white females.

Dynamic chest radiography: flat-panel detector (FPD) based functional X-ray imaging.

PubMed

Tanaka, Rie

2016-07-01

Dynamic chest radiography is a flat-panel detector (FPD)-based functional X-ray imaging, which is performed as an additional examination in chest radiography. The large field of view (FOV) of FPDs permits real-time observation of the entire lungs and simultaneous right-and-left evaluation of diaphragm kinetics. Most importantly, dynamic chest radiography provides pulmonary ventilation and circulation findings as slight changes in pixel value even without the use of contrast media; the interpretation is challenging and crucial for a better understanding of pulmonary function. The basic concept was proposed in the 1980s; however, it was not realized until the 2010s because of technical limitations. Dynamic FPDs and advanced digital image processing played a key role for clinical application of dynamic chest radiography. Pulmonary ventilation and circulation can be quantified and visualized for the diagnosis of pulmonary diseases. Dynamic chest radiography can be deployed as a simple and rapid means of functional imaging in both routine and emergency medicine. Here, we focus on the evaluation of pulmonary ventilation and circulation. This review article describes the basic mechanism of imaging findings according to pulmonary/circulation physiology, followed by imaging procedures, analysis method, and diagnostic performance of dynamic chest radiography.

Quality aspects of digital radiography in general dental practice.

PubMed

Hellén-Halme, Kristina

2007-01-01

The number of dentists who have converted from conventional film radiography to digital radiography continues to grow. A digital system has numerous advantages, but there are also many new aspects to consider. The overall aim of this thesis was to study how digital radiography was used in general dental practices. The specific aims were to study how different factors affected image quality. To determine whether there were any differences in image quality between conventional film radiographs and digital radiographs, 4863 images (540 cases) were evaluated. The cases had been sent to the Swedish Dental Insurance Office for prior treatment approval. The image quality of digital radiographs was found to be significantly lower than that of film radiographs. This result led to a questionnaire study of dentists experienced in digital radiography. In 2003, a questionnaire was sent to the 139 general practice dentists who worked with digital radiography in Skine, Sweden; the response rate was 94%. Many general practice dentists had experienced several problems (65%), and less than half of the digital systems (40%) underwent some kind of quality control. One of the weaker links in the technical chain of digital radiography appeared to be the monitor. A field study to 19 dentists at their clinics found that the brightness and contrast settings of the monitors had to be adjusted to obtain the subjectively best image quality. The ambient light in the evaluation room was also found to affect the diagnostic outcome of low-contrast patterns in radiographs. To evaluate the effects of ambient light and technical adjustments of the monitor, a study using standardised set-ups was designed. Seven observers evaluated radiographs of 100 extracted human teeth for approximal caries under five different combinations of brightness and contrast settings on two different occasions with high and low ambient light levels in the evaluation room. The ability to diagnose carious lesions was found

Magnifying lens for 800 MeV proton radiography.

PubMed

Merrill, F E; Campos, E; Espinoza, C; Hogan, G; Hollander, B; Lopez, J; Mariam, F G; Morley, D; Morris, C L; Murray, M; Saunders, A; Schwartz, C; Thompson, T N

2011-10-01

This article describes the design and performance of a magnifying magnetic-lens system designed, built, and commissioned at the Los Alamos National Laboratory (LANL) for 800 MeV flash proton radiography. The technique of flash proton radiography has been developed at LANL to study material properties under dynamic loading conditions through the analysis of time sequences of proton radiographs. The requirements of this growing experimental program have resulted in the need for improvements in spatial radiographic resolution. To meet these needs, a new magnetic lens system, consisting of four permanent magnet quadrupoles, has been developed. This new lens system was designed to reduce the second order chromatic aberrations, the dominant source of image blur in 800 MeV proton radiography, as well as magnifying the image to reduce the blur contribution from the detector and camera systems. The recently commissioned lens system performed as designed, providing nearly a factor of three improvement in radiographic resolution.

Magnifying lens for 800 MeV proton radiography

NASA Astrophysics Data System (ADS)

Merrill, F. E.; Campos, E.; Espinoza, C.; Hogan, G.; Hollander, B.; Lopez, J.; Mariam, F. G.; Morley, D.; Morris, C. L.; Murray, M.; Saunders, A.; Schwartz, C.; Thompson, T. N.

2011-10-01

This article describes the design and performance of a magnifying magnetic-lens system designed, built, and commissioned at the Los Alamos National Laboratory (LANL) for 800 MeV flash proton radiography. The technique of flash proton radiography has been developed at LANL to study material properties under dynamic loading conditions through the analysis of time sequences of proton radiographs. The requirements of this growing experimental program have resulted in the need for improvements in spatial radiographic resolution. To meet these needs, a new magnetic lens system, consisting of four permanent magnet quadrupoles, has been developed. This new lens system was designed to reduce the second order chromatic aberrations, the dominant source of image blur in 800 MeV proton radiography, as well as magnifying the image to reduce the blur contribution from the detector and camera systems. The recently commissioned lens system performed as designed, providing nearly a factor of three improvement in radiographic resolution.

Dose audit for patients undergoing two common radiography examinations with digital radiology systems

PubMed Central

İnal, Tolga; Ataç, Gökçe

2014-01-01

PURPOSE We aimed to determine the radiation doses delivered to patients undergoing general examinations using computed or digital radiography systems in Turkey. MATERIALS AND METHODS Radiographs of 20 patients undergoing posteroanterior chest X-ray and of 20 patients undergoing anteroposterior kidney-ureter-bladder radiography were evaluated in five X-ray rooms at four local hospitals in the Ankara region. Currently, almost all radiology departments in Turkey have switched from conventional radiography systems to computed radiography or digital radiography systems. Patient dose was measured for both systems. The results were compared with published diagnostic reference levels (DRLs) from the European Union and International Atomic Energy Agency. RESULTS The average entrance surface doses (ESDs) for chest examinations exceeded established international DRLs at two of the X-ray rooms in a hospital with computed radiography. All of the other ESD measurements were approximately equal to or below the DRLs for both examinations in all of the remaining hospitals. Improper adjustment of the exposure parameters, uncalibrated automatic exposure control systems, and failure of the technologists to choose exposure parameters properly were problems we noticed during the study. CONCLUSION This study is an initial attempt at establishing local DRL values for digital radiography systems, and will provide a benchmark so that the authorities can establish reference dose levels for diagnostic radiology in Turkey. PMID:24317331

Prediction of low bone mass using a combinational approach of cortical and trabecular bone measures from dental panoramic radiographs.

PubMed

Kathirvelu, D; Anburajan, M

2014-09-01

The aim of this study is to extract cortical and trabecular features of the mandible and to develop a novel combinational model of mandibular cortical thickness, trabecular bone area and age in order to predict low bone mineral density or osteoporosis from a dental panoramic radiograph. The study involved 64 south Indian women (age = 52.5 ± 12.7 years) categorised into two groups (normal and low bone mineral density) based on total femur bone mineral density. The dental panoramic radiographs were obtained by a digital scanner, and measurement of total bone mineral density at the right femur was performed by a dual-energy X-ray absorptiometry scanner. The mandibular cortical thickness and panoramic mandibular index were measured bilaterally, and the mean values were considered. The region of interest of 128 × 128 pixels around the mental foramen region was manually cropped and subjected to pre-processing, normalisation and average threshold-based segmentation to determine trabecular bone area. Multiple linear regression analyses of cortical and trabecular measures along with age were performed to develop a combinational model to classify subjects as normal and low bone mineral density. The proposed approach demonstrated strong correlation (r = 0.76; p < 0.01) against the total bone mineral density and resulted in accuracy, sensitivity and positive predictive values of 0.84, 0.92 and 0.85, respectively; the receiver operating characteristic outcomes disclosed that the area under the curve was 0.89.Our results suggest that the proposed combinational model could be useful to diagnose subjects with low bone mineral density. © IMechE 2014.

Radiography student perceptions of clinical stressors.

PubMed

Mason, Starla L

2006-01-01

Technological change and the increasingly rapid pace of life in the United States and globally have contributed to increased levels of stress and burnout experienced by workers and their families. Although studies are available on the levels of workplace stress and burnout affecting radiographers, little to no research has been conducted to assess the stressors encountered by radiography students in the clinical environment. This study was designed to pinpoint the primary sources of stress for radiography students and to determine the most effective measures to alleviate the stress that students experience in the clinical environment. It also sought to identify the clinical activities and practices that enhance learning. A convenience sample of radiography students attending an Association of Collegiate Educators in Radiologic Technology meeting was surveyed. Students were asked to rank their greatest stressors in the clinical environment, the most desired qualities in a clinical instructor and clinical environment, and the clinical practices and activities that best enhance their learning. Descriptive statistics were used to report the results. Data were collected for 82 first-year and second-year students. Students identified 7 primary clinical stressors: fear of making a mistake/repeat, feeling unprepared/inexperienced, intimidation by staff and by instructors, difficult/critical patients, hurtful criticism, too much supervision and negative responses to questions/requests for help. Students indicated that more frequent feedback, availability of the clinical instructor and other staff, assurance that mistakes happen and the opportunity to make mistakes were clinical practices that eased stress. The majority of students cited hands-on learning and repetition as the clinical activities that most reinforced their learning. Summary Radiography students in this survey experience some of the same clinical stressors as radiographers and other allied health workers

Outcome of recommendations for radiographic follow-up of pneumonia on outpatient chest radiography.

PubMed

Little, Brent P; Gilman, Matthew D; Humphrey, Kathryn L; Alkasab, Tarik K; Gibbons, Fiona K; Shepard, Jo-Anne O; Wu, Carol C

2014-01-01

Follow-up chest radiographs are frequently recommended by radiologists to document the clearing of radiographically suspected pneumonia. However, the clinical utility of follow-up radiography is not well understood. The purpose of this study was to examine the incidence of important pulmonary pathology revealed during follow-up imaging of suspected pneumonia on outpatient chest radiography. Reports of 29,138 outpatient chest radiography examinations performed at an academic medical center in 2008 were searched to identify cases in which the radiologist recommended follow-up chest radiography for presumed community-acquired pneumonia (n = 618). Descriptions of index radiographic abnormalities were recorded. Reports of follow-up imaging (radiography and CT) performed during the period from January 2008 to January 2010 were reviewed to assess the outcome of the index abnormality. Clinical history, demographics, microbiology, and pathology reports were reviewed and recorded. Compliance with follow-up imaging recommendations was 76.7%. In nine of 618 cases (1.5%), a newly diagnosed malignancy corresponded to the abnormality on chest radiography initially suspected to be pneumonia. In 23 of 618 cases (3.7%), an alternative nonmalignant disease corresponded with the abnormality on chest radiography initially suspected to be pneumonia. Therefore, in 32 of 618 patients (5.2%), significant new pulmonary diagnoses were established during follow-up imaging of suspected pneumonia. Follow-up imaging of radiographically suspected pneumonia leads to a small number of new diagnoses of malignancy and important nonmalignant diseases, which may alter patient management.

Grid artifact reduction for direct digital radiography detectors based on rotated stationary grids with homomorphic filtering

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Dong Sik; Lee, Sanggyun

2013-06-15

Purpose: Grid artifacts are caused when using the antiscatter grid in obtaining digital x-ray images. In this paper, research on grid artifact reduction techniques is conducted especially for the direct detectors, which are based on amorphous selenium. Methods: In order to analyze and reduce the grid artifacts, the authors consider a multiplicative grid image model and propose a homomorphic filtering technique. For minimal damage due to filters, which are used to suppress the grid artifacts, rotated grids with respect to the sampling direction are employed, and min-max optimization problems for searching optimal grid frequencies and angles for given sampling frequenciesmore » are established. The authors then propose algorithms for the grid artifact reduction based on the band-stop filters as well as low-pass filters. Results: The proposed algorithms are experimentally tested for digital x-ray images, which are obtained from direct detectors with the rotated grids, and are compared with other algorithms. It is shown that the proposed algorithms can successfully reduce the grid artifacts for direct detectors. Conclusions: By employing the homomorphic filtering technique, the authors can considerably suppress the strong grid artifacts with relatively narrow-bandwidth filters compared to the normal filtering case. Using rotated grids also significantly reduces the ringing artifact. Furthermore, for specific grid frequencies and angles, the authors can use simple homomorphic low-pass filters in the spatial domain, and thus alleviate the grid artifacts with very low implementation complexity.« less

System for uncollimated digital radiography

DOEpatents

Wang, Han; Hall, James M.; McCarrick, James F.; Tang, Vincent

2015-08-11

The inversion algorithm based on the maximum entropy method (MEM) removes unwanted effects in high energy imaging resulting from an uncollimated source interacting with a finitely thick scintillator. The algorithm takes as input the image from the thick scintillator (TS) and the radiography setup geometry. The algorithm then outputs a restored image which appears as if taken with an infinitesimally thin scintillator (ITS). Inversion is accomplished by numerically generating a probabilistic model relating the ITS image to the TS image and then inverting this model on the TS image through MEM. This reconstruction technique can reduce the exposure time or the required source intensity without undesirable object blurring on the image by allowing the use of both thicker scintillators with higher efficiencies and closer source-to-detector distances to maximize incident radiation flux. The technique is applicable in radiographic applications including fast neutron, high-energy gamma and x-ray radiography using thick scintillators.

Megavoltage cargo radiography with dual energy material decomposition

NASA Astrophysics Data System (ADS)

Shikhaliev, Polad M.

2018-02-01

Megavoltage (MV) radiography has important applications in imaging large cargos for detecting illicit materials. A useful feature of MV radiography is the possibility of decomposing and quantifying materials with different atomic numbers. This can be achieved by imaging cargo at two different X-ray energies, or dual energy (DE) radiography. The performance of both single energy and DE radiography depends on beam energy, beam filtration, radiation dose, object size, and object content. The purpose of this work was to perform comprehensive qualitative and quantitative investigations of the image quality in MV radiography depending on the above parameters. A digital phantom was designed including Fe background with thicknesses of 2cm, 6cm, and 18cm, and materials samples of Polyethylene, Fe, Pb, and U. The single energy images were generated at x-ray beam energies 3.5MV, 6MV, and 9MV. The DE material decomposed images were generated using interlaced low and high energy beams 3.5/6MV and 6/9MV. The X-ray beams were filtered by low-Z (Polyethylene) and high-Z (Pb) filters with variable thicknesses. The radiation output of the accelerator was kept constant for all beam energies. The image quality metrics was signal-to-noise ratio (SNR) of the particular sample over a particular background. It was found that the SNR depends on the above parameters in a complex way, but can be optimized by selecting a particular set of parameters. For some imaging setups increased filter thicknesses, while strongly absorbing the beams, increased the SNR of material decomposed images. Beam hardening due to polyenergetic x-ray spectra resulted in material decomposition errors, but this could be addressed using region of interest decomposition. It was shown that it is not feasible to separate the materials with close atomic numbers using the DE method. Particularly, Pb and U were difficult to decompose, at least at the dose levels allowed by radiation source and safety requirements.

A survey of digital radiography practice in four South African teaching hospitals: an illuminative study.

PubMed

Nyathi, T; Chirwa, Tf; van der Merwe, Dg

2010-01-01

The purpose of this study was to assess radiographer familiarity and preferences with digital radiography in four teaching hospitals and thereafter make recommendations in line with the migration from screen film to digital radiography. A questionnaire was designed to collect data from either qualified or student radiographers from four teaching hospitals. From the four teaching hospitals, there were a total of 205 potential respondents. Among other things, responses regarding experiences and preferences with digital radiography, quality control procedures, patient dose, advantages and disadvantages of digital radiography were sought. The information collected was based on self-reporting by the participants. The study is exploratory in nature and descriptive statistics were generated from the collected data using Microsoft Excel 2007 and StatsDirect software. Sixty-three out of 205 (31%) radiographers from all the four radiology centers responded to the circulated questionnaire. Only 15% (8) of the qualified radiographers had 4 or more years of experience with digital radiography compared to 68% (36) for the same amount of experience with screen-film radiography. Sixty-one percent (38) of the participants had been exposed to digital radiography during their lectures while at university. A small proportion, 16% (10) of the respondents underwent formal training in quality control procedures on the digital X-ray units they were using. Slightly more than half (55%) of the participants felt it was easier for them to retake an image in digital radiography than in screen film radiography. The results of this survey showed that the participants are familiar with digital radiography and have embraced this relatively new technology as shown by the fact that they can identify both its advantages and disadvantages as applied to clinical practice. However, there are minimal quality control procedures specific to digital radiography being undertaken as such there is need for

WE-EF-303-10: Single- Detector Proton Radiography as a Portal Imaging Equivalent for Proton Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Doolan, P; Bentefour, E; Testa, M

2015-06-15

Purpose: In proton therapy, patient alignment is of critical importance due to the sensitivity of the proton range to tissue heterogeneities. Traditionally proton radiography is used for verification of the water-equivalent path length (WEPL), which dictates the depth protons reach. In this work we propose its use for alignment. Additionally, many new proton centers have cone-beam computed tomography in place of beamline X-ray imaging and so proton radiography offers a unique patient alignment verification similar to portal imaging in photon therapy. Method: Proton radiographs of a CIRS head phantom were acquired using the Beam Imaging System (BIS) (IBA, Louvain-la-Neuve) inmore » a horizontal beamline. A scattered beam was produced using a small, dedicated, range modulator (RM) wheel fabricated out of aluminum. The RM wheel was rotated slowly (20 sec/rev) using a stepper motor to compensate for the frame rate of the BIS (120 ms). Dose rate functions (DRFs) over two RM wheel rotations were acquired. Calibration was made with known thicknesses of homogeneous solid water. For each pixel the time width, skewness and kurtosis of the DRFs were computed. The time width was used to compute the object WEPL. In the heterogeneous phantom, the excess skewness and excess kurtosis (i.e. difference from homogeneous cases) were computed and assessed for suitability for patient set up. Results: The technique allowed for the simultaneous production of images that can be used for WEPL verification, showing few internal details, and excess skewness and kurtosis images that can be used for soft tissue alignment. These latter images highlight areas where range mixing has occurred, correlating with phantom heterogeneities. Conclusion: The excess skewness and kurtosis images contain details that are not visible in the WET images. These images, unique to the time-resolved proton radiographic method, could be used for patient set up according to soft tissues.« less

Scatter in Cargo Radiography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Erin A. Miller; Joseph A. Caggiano; Robert C. Runkle

As a complement to passive detection systems, radiographic inspection of cargo is an increasingly important tool for homeland security because it has the potential to detect highly attenuating objects associated with special nuclear material or surrounding shielding, in addition to screening for items such as drugs or contraband. Radiographic detection of such threat objects relies on high image contrast between regions of different density and atomic number (Z). Threat detection is affected by scatter of the interrogating beamin the cargo, the radiographic system itself, and the surrounding environment, which degrades image contrast. Here, we estimate the extent to which scattermore » plays a role in radiographic imaging of cargo containers. Stochastic transport simulations were performed to determine the details of the radiography equipment and surrounding environment, which are important in reproducing measured data and to investigate scatter magnitudes for typical cargo. We find that scatter plays a stronger role in cargo radiography than in typicalmedical imaging scenarios, even for low-density cargo, with scatter-toprimary ratios ranging from 0.14 for very low density cargo, to between 0.20 and 0.40 for typical cargo, and higher yet for dense cargo.« less

General Dental Practitioners’ Concept towards Using Radiography and Apex-Locators in Endodontics

PubMed Central

Raoof, Maryam; Heidaripour, Maryam; Shahravan, Arash; Haghani, Jahangir; Afkham, Arash; Razifar, Mahsa; Mohammadizadeh, Sakineh

2014-01-01

Introduction: Despite being the gold standard as well as a routine technique in endodontics, radiographic working length (WL) determination owns many drawbacks. Electronic apex-locators (EALs) are recommended to complement radiographies. The aim of this study was to evaluate the perceptions of Iranian general dental practitioners (GDPs) towards using radiography and EAL. Methods and Materials: Three hundred and ninety one GDPs attending the 53th Iranian Dental Association Congress completed a questionnaire focusing on the use of radiography and EALs during the various stages of root canal treatment. The data was analyzed with the chi-square test with the level of significance set at 0.05. The results were then calculated as frequencies and percentages. Results: More than half of the GDPs reported using radiographs as the sole method for WL determination. A total of 30.4% of the practitioners were using the combined approach during root canal therapy of a single-rooted tooth, while 38.9% used this method in multi-rooted teeth. Approximately half of the respondents would not order follow-up radiographies after root canal treatment. Conclusion: Radiography continues to be the most common method for WL determination in Iran. PMID:25386209

Final-year diagnostic radiography students' perception of role models within the profession.

PubMed

Conway, Alinya; Lewis, Sarah; Robinson, John

2008-01-01

Within a clinical education setting, the value of role models and prescribed mentors can be seen as an important influence in shaping the student's future as a diagnostic radiographer. A study was undertaken to create a new understanding of how diagnostic radiography students perceive role models and professional behavior in the workforce. The study aimed to determine the impact of clinical education in determining modeling expectations, role model identification and attributes, and the integration of academic education and "hands-on" clinical practice in preparing diagnostic radiography students to enter the workplace. Thirteen final-year (third-year) diagnostic radiography students completed an hour-long interview regarding their experiences and perceptions of role models while on clinical placement. The key concepts that emerged illustrated that students gravitate toward radiographers who enjoy sharing practical experiences with students and are good communicators. Unique to diagnostic radiography, students made distinctions about the presence of role models in private versus public service delivery. This study gives insight to clinical educators in diagnostic radiography and wider allied health into how students perceive role models, interact with preceptors, and combine real-life experiences with formal learning.

Internal anatomy of the hornbill casque described by radiography, contrast radiography, and computed tomography.

PubMed

Gamble, Kathryn C

2007-03-01

Hornbills are distinguished from most other avian taxa by the presence of a casque on the dorsal maxillary beak, which, in all but 1 of the 54 extant hornbill species, is described as essentially an air-filled cavity enclosed by minimal cancellous bone. The external casque has been described in detail, but little has been described about its internal anatomy and the communications between the casque and the paranasal sinuses. In this study, 10 intact casque and skull specimens of 7 hornbill species were collected opportunistically at necropsy. The anatomy of the casque and the skull for each of the specimens was examined by radiography, contrast radiography, and computed tomography. After imaging, 8 specimens were submitted for osteologic preparation to directly visualize the casque and the skull interior. Through this standardized review, the baseline anatomy of the internal casque was described, including identification of a novel casque sinus within the paranasal sinus system. These observations will assist clinicians in the diagnosis and treatment of diseases of the casque in hornbill species.

Forensic Odontology: Automatic Identification of Persons Comparing Antemortem and Postmortem Panoramic Radiographs Using Computer Vision.

PubMed

Heinrich, Andreas; Güttler, Felix; Wendt, Sebastian; Schenkl, Sebastian; Hubig, Michael; Wagner, Rebecca; Mall, Gita; Teichgräber, Ulf

2018-06-18

 In forensic odontology the comparison between antemortem and postmortem panoramic radiographs (PRs) is a reliable method for person identification. The purpose of this study was to improve and automate identification of unknown people by comparison between antemortem and postmortem PR using computer vision.  The study includes 43 467 PRs from 24 545 patients (46 % females/54 % males). All PRs were filtered and evaluated with Matlab R2014b including the toolboxes image processing and computer vision system. The matching process used the SURF feature to find the corresponding points between two PRs (unknown person and database entry) out of the whole database.  From 40 randomly selected persons, 34 persons (85 %) could be reliably identified by corresponding PR matching points between an already existing scan in the database and the most recent PR. The systematic matching yielded a maximum of 259 points for a successful identification between two different PRs of the same person and a maximum of 12 corresponding matching points for other non-identical persons in the database. Hence 12 matching points are the threshold for reliable assignment.  Operating with an automatic PR system and computer vision could be a successful and reliable tool for identification purposes. The applied method distinguishes itself by virtue of its fast and reliable identification of persons by PR. This Identification method is suitable even if dental characteristics were removed or added in the past. The system seems to be robust for large amounts of data.   · Computer vision allows an automated antemortem and postmortem comparison of panoramic radiographs (PRs) for person identification.. · The present method is able to find identical matching partners among huge datasets (big data) in a short computing time.. · The identification method is suitable even if dental characteristics were removed or added.. · Heinrich A, Güttler F, Wendt S et al. Forensic Odontology

Repeat rates in digital chest radiography and strategies for improvement.

PubMed

Fintelmann, Florian; Pulli, Benjamin; Abedi-Tari, Faezeh; Trombley, Maureen; Shore, Mary-Theresa; Shepard, Jo-Anne; Rosenthal, Daniel I

2012-05-01

To determine the repeat rate (RR) of chest radiographs acquired with portable computed radiography (CR) and installed direct radiography (DR) and to develop and assess strategies designed to decrease the RR. The RR and reasons for repeated digital chest radiographs were documented over the course of 16 months while a task force of thoracic radiologists, technologist supervisors, technologists, and information technology specialists continued to examine the workflow for underlying causes. Interventions decreasing the RR were designed and implemented. The initial RR of digital chest radiographs was 3.6% (138/3818) for portable CR and 13.3% (476/3575) for installed DR systems. By combining RR measurement with workflow analysis, targets for technical and teaching interventions were identified. The interventions decreased the RR to 1.8% (81/4476) for portable CR and to 8.2% (306/3748) for installed DR. We found the RR of direct digital chest radiography to be significantly higher than that of computed chest radiography. We believe this is due to the ease with which repeat images can be obtained and discarded, and it suggests the need for ongoing surveillance of RR. We were able to demonstrate that strategies to lower the RR, which had been developed in the era of film-based imaging, can be adapted to the digital environment. On the basis of our findings, we encourage radiologists to assess their own departmental RRs for direct digital chest radiography and to consider similar interventions if necessary to achieve acceptable RRs for this modality.

A clinico-radiographic analysis of sagittal condylar guidance determined by protrusive interocclusal registration and panoramic radiographic images in humans

PubMed Central

Prasad, Krishna D.; Shah, Namrata; Hegde, Chethan

2012-01-01

Purpose: To evaluate the correlation between sagittal condylar guidance obtained by protrusive interocclusal records and panoramic radiograph tracing methods in human dentulous subjects. Materials and Methods: The sagittal condylar guidance was determined in 75 dentulous subjects by protrusive interocclusal records using Aluwax through a face bow transfer (HANAU™ Spring Bow, Whip Mix Corporation, USA) to a semi-adjustable articulator (HANAU™ Wide-Vue Articulator, Whip Mix Corporation, USA). In the same subjects, the sagittal outline of the articular eminence and glenoid fossa was traced in panoramic radiographs. The sagittal condylar path inclination was constructed by joining the heights of curvature in the glenoid fossa and the corresponding articular eminence. This was then related to the constructed Frankfurt's horizontal plane to determine the radiographic angle of sagittal condylar guidance. Results: A strong positive correlation existed between right and left condylar guidance by the protrusive interocclusal method (P 0.000) and similarly by the radiographic method (P 0.013). The mean difference between the condylar guidance obtained using both methods were 1.97° for the right side and 3.18° for the left side. This difference between the values by the two methods was found to be highly significant for the right (P 0.003) and left side (P 0.000), respectively. The sagittal condylar guidance obtained from both methods showed a significant positive correlation on right (P 0.000) and left side (P 0.015), respectively. Conclusion: Panoramic radiographic tracings of the sagittal condylar path guidance may be made relative to the Frankfurt's horizontal reference plane and the resulting condylar guidance angles used to set the condylar guide settings of semi-adjustable articulators. PMID:23633793

Radiography Students' Learning: A Literature Review.

PubMed

Holmström, Anneli; Ahonen, Sanna-Mari

2016-01-01

To describe research methodology and findings concerning radiography students' learning. Health sciences databases were searched to perform a traditional narrative literature review. Thirty-five peer-reviewed articles published between 2000 and 2014 were analyzed using thematic analysis. Specific methods of learning were found to be of the most interest. The studies focused primarily on the use and usability of a method or the students' general experiences of it. The most commonly studied methods were e-learning and interprofessional learning, which students perceived as positive methods for theoretical studies and clinical training. Students' learning regarding research was the focus of only one article reporting a wide variety of students' research interests. Most studies reported quantitative research gathered from questionnaires and surveys. Additional research, especially from a qualitative point of view, is needed to deepen the evidence-based knowledge of radiography student learning.

Simple methods to reduce patient exposure during scoliosis radiography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Butler, P.F.; Thomas, A.W.; Thompson, W.E.

1986-05-01

Radiation exposure to the breasts of adolescent females can be reduced significantly through the use of one or all of the following methods: fast, rare-earth screen-film combinations; specially designed compensating filters; and breast shielding. The importance of exposure reduction during scoliosis radiography as well as further details on the above described methods are discussed. In addition, the early results of a Center for Devices and Radiological Health study, which recorded exposure and technique data for scoliosis radiography, is presented.

Small-scale anomaly detection in panoramic imaging using neural models of low-level vision

NASA Astrophysics Data System (ADS)

Casey, Matthew C.; Hickman, Duncan L.; Pavlou, Athanasios; Sadler, James R. E.

2011-06-01

Our understanding of sensory processing in animals has reached the stage where we can exploit neurobiological principles in commercial systems. In human vision, one brain structure that offers insight into how we might detect anomalies in real-time imaging is the superior colliculus (SC). The SC is a small structure that rapidly orients our eyes to a movement, sound or touch that it detects, even when the stimulus may be on a small-scale; think of a camouflaged movement or the rustle of leaves. This automatic orientation allows us to prioritize the use of our eyes to raise awareness of a potential threat, such as a predator approaching stealthily. In this paper we describe the application of a neural network model of the SC to the detection of anomalies in panoramic imaging. The neural approach consists of a mosaic of topographic maps that are each trained using competitive Hebbian learning to rapidly detect image features of a pre-defined shape and scale. What makes this approach interesting is the ability of the competition between neurons to automatically filter noise, yet with the capability of generalizing the desired shape and scale. We will present the results of this technique applied to the real-time detection of obscured targets in visible-band panoramic CCTV images. Using background subtraction to highlight potential movement, the technique is able to correctly identify targets which span as little as 3 pixels wide while filtering small-scale noise.

Impact of chest radiography for children with lower respiratory tract infection: a propensity score approach.

PubMed

Ecochard-Dugelay, Emmanuelle; Beliah, Muriel; Boisson, Caroline; Perreaux, Francis; de Laveaucoupet, Jocelyne; Labrune, Philippe; Epaud, Ralph; Ducou-Lepointe, Hubert; Bouyer, Jean; Gajdos, Vincent

2014-01-01

Management of acute respiratory tract infection varies substantially despite this being a condition frequently encountered in pediatric emergency departments. Previous studies have suggested that the use of antibiotics was higher when chest radiography was performed. However none of these analyses had considered the inherent indication bias of observational studies. The aim of this work was to assess the relationship between performing chest radiography and prescribing antibiotics using a propensity score analysis to address the indication bias due to non-random radiography assignment. We conducted a prospective study of 697 children younger than 2 years of age who presented during the winter months of 2006-2007 for suspicion of respiratory tract infection at the Pediatric Emergency Department of an urban general hospital in France (Paris suburb). We first determined the individual propensity score (probability of having a chest radiography according to baseline characteristics). Then we assessed the relation between radiography and antibiotic prescription using two methods: adjustment and matching on the propensity score. We found that performing a chest radiography lead to more frequent antibiotic prescription that may be expressed as OR = 2.3, CI [1.3-4.1], or as an increased use of antibiotics of 18.6% [0.08-0.29] in the group undergoing chest radiography. Chest radiography has a significant impact on the management of infants admitted for suspicion of respiratory tract infection in a pediatric emergency department and may lead to unnecessary administration of antibiotics.

Panographic Survey of U. S. Army Recruits: Analysis of Dental Health Status.

DTIC Science & Technology

1981-09-16

pathoses which may not be evident on a routine periapical survey.3-6 The advantages of panoramic radiography make it particularly attractive for mass...perlapical radiolucencles. Radiolucent lesions, other than periapical or anatomical, were recorded separately. Folli- cular enlargements (over 3 m) surrounding...retention cysts . RESULTS Table I summarizes the findings. Dental Caries. A 58 percent incidence of carious lesions was noted overall. Many of these lesions

Repetitive compact flash x-ray generators for soft radiography

NASA Astrophysics Data System (ADS)

Sato, Eiichi; Shikoda, Arimitsu; Kimura, Shingo; Sagae, Michiaki; Oizumi, Teiji; Takahashi, Kei; Hayasi, Yasuomi; Shoji, Tetsuo; Shishido, Koro; Tamakawa, Yoshiharu; Yanagisawa, Toru

1993-01-01

The construction and the fundamental studies for the repetitive flash x-ray generators designed by Japan Impulse Laboratory in Iwate Medical University are described. These generators are classified to the following two major types: (1) generators having diodes, and (2) generators having triodes. In order to generate high-voltage impulses, we employed the following transmission lines (pulsers): (a) high-voltage-inversion type with a maximum output voltage Vom of about 80 kV, (b) high-voltage- inversion type having a coaxial cable (Vom equals 130 kV), (c) two-stage Marx pulser (Vom equals 150 kV), (d) two-cable-type Blumlein (Vom equals 120 kV), (e) modified Blumlein (Vom equals 120 kV), (f) fundamental transmission line for triode (Vom equals 100 kV), and (g) transmission line for an enclosed triode (Vom equals 100 kV). Using these generators we succeeded in performing high-speed radiography as follows: (a) delayed radiography; (b) multiple-shot radiography; and (c) cineradiography.

Plain abdominal radiography in acute abdominal pain; past, present, and future

PubMed Central

Gans, Sarah L; Stoker, Jaap; Boermeester, Marja A

2012-01-01

Several studies have demonstrated that a diagnosis based solely on a patient’s medical history, physical examination, and laboratory tests is not reliable enough, despite the fact that these aspects are essential parts of the workup of a patient presenting with acute abdominal pain. Traditionally, imaging workup starts with abdominal radiography. However, numerous studies have demonstrated low sensitivity and accuracy for plain abdominal radiography in the evaluation of acute abdominal pain as well as various specific diseases such as perforated viscus, bowel obstruction, ingested foreign body, and ureteral stones. Computed tomography, and in particular computed tomography after negative ultrasonography, provides a better workup than plain abdominal radiography alone. The benefits of computed tomography lie in decision-making for management, planning of a surgical strategy, and possibly even avoidance of negative laparotomies. Based on abundant available evidence, major advances in diagnostic imaging, and changes in the management of certain diseases, we can conclude that there is no place for plain abdominal radiography in the workup of adult patients with acute abdominal pain presenting in the emergency department in current practice. PMID:22807640

Adherence to radiography guidelines for low back pain: a survey of chiropractic schools worldwide.

PubMed

Ammendolia, Carlo; Taylor, John A M; Pennick, Victoria; Côté, Pierre; Hogg-Johnson, Sheilah; Bombardier, Claire

2008-01-01

This study describes instruction provided at chiropractic schools worldwide on the use of spine radiography and compares instruction with evidence-based guidelines for low back pain. Individuals responsible for radiology instruction at accredited chiropractic schools throughout the world were contacted and invited to participate in a Web-based survey. The survey included questions on the role of conventional radiography in chiropractic practice and instruction given to students for its use in patients with acute low back pain. Of the 33 chiropractic schools identified worldwide, 32 (97%) participated in the survey. Consistent with the guidelines, 25 (78%) respondents disagreed that "routine radiography should be used prior to spinal manipulative therapy," 29 (91%) disagreed that there "was a role for full spine radiography for assessing patients with low back pain," and 29 (91%) disagreed that "oblique views should be part of a standard radiographic series for low back pain." However, only 14 (44%) respondents concurred with the guidelines and disagreed with the statement that there "is a role for radiography in acute low back pain in the absence of 'red flags' for serious disease." This survey suggests that many aspects of radiology instruction provided by accredited chiropractic schools appear to be evidence based. However, there appears to be a disparity between some schools and existing evidence with respect to the role of radiography for patients with acute low back pain without "red flags" for serious disease. This may contribute to chiropractic overutilization of radiography for low back pain.

10 CFR 34.61 - Records of the specific license for industrial radiography.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 1 2013-01-01 2013-01-01 false Records of the specific license for industrial radiography. 34.61 Section 34.61 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Recordkeeping Requirements § 34.61...

10 CFR 34.61 - Records of the specific license for industrial radiography.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 1 2014-01-01 2014-01-01 false Records of the specific license for industrial radiography. 34.61 Section 34.61 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Recordkeeping Requirements § 34.61...

10 CFR 34.61 - Records of the specific license for industrial radiography.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 1 2011-01-01 2011-01-01 false Records of the specific license for industrial radiography. 34.61 Section 34.61 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Recordkeeping Requirements § 34.61...

10 CFR 34.61 - Records of the specific license for industrial radiography.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 1 2012-01-01 2012-01-01 false Records of the specific license for industrial radiography. 34.61 Section 34.61 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Recordkeeping Requirements § 34.61...

10 CFR 34.61 - Records of the specific license for industrial radiography.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Records of the specific license for industrial radiography. 34.61 Section 34.61 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Recordkeeping Requirements § 34.61...

An evaluation of author productivity in international radiography journals 2004–2011

DOE Office of Scientific and Technical Information (OSTI.GOV)

Snaith, Beverly A

Radiography, the allied health profession, has changed beyond recognition over the last century; however, in academic terms radiography is a relatively young profession. It is therefore still establishing its professional knowledge base. This article uses peer-review author productivity distribution to evaluate its scholarly maturity. Four peer-reviewed journals in medical radiation sciences were examined over an 8-year period (2004–2011) and author productivity was compared to Lotka's law. Further analysis of the most prolific authors provided an evaluation of their characteristics. The 1306 unique authors contributed 835 articles during the study period. Of these, 1012 (77.5%) contributed only one article to themore » journals studied, with an inverse power relationship of author productivity. At the 0.1 level of significance, radiography does not fit Lotka's law (n = −2.334; c = 0.712; D{sub max} = 0.0627; Critical threshold = 0.0337). There was a significant correlation between the most prolific authors and collaboration (P = 0.002), although variation was noted in author discipline and location. The results of this study add to the discussion of radiography scholarship and demonstrate that the radiography authors have similar productivity distribution to other professions, but do not follow Lotka's law.« less

Neutron Radiography and Computed Tomography at Oak Ridge National Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raine, Dudley A. III; Hubbard, Camden R.; Whaley, Paul M.

1997-12-31

The capability to perform neutron radiography and computed tomography is being developed at Oak Ridge National Laboratory. The facility will be located at the High Flux Isotope Reactor (HFIR), which has the highest steady state neutron flux of any reactor in the world. The Monte Carlo N-Particle transport code (MCNP), versions 4A and 4B, has been used extensively in the design phase of the facility to predict and optimize the operating characteristics, and to ensure the safety of personnel working in and around the blockhouse. Neutrons are quite penetrating in most engineering materials and can be useful to detect internalmore » flaws and features. Hydrogen atoms, such as in a hydrocarbon fuel, lubricant or a metal hydride, are relatively opaque to neutron transmission. Thus, neutron based tomography or radiography is ideal to image their presence. The source flux also provides unparalleled flexibility for future upgrades, including real time radiography where dynamic processes can be observed. A novel tomography detector has been designed using optical fibers and digital technology to provide a large dynamic range for reconstructions. Film radiography is also available for high resolution imaging applications. This paper summarizes the results of the design phase of this facility and the potential benefits to science and industry.« less

Reduction of radiation exposure during radiography for scoliosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gray, J.E.; Hoffman, A.D.; Peterson, H.A.

1983-01-01

To reduce the radiation exposure received by young scoliosis patients during treatment, six changes in technique were instituted: (1) a posteroanterior projection, (2) specially designed leaded acrylic filters, (3) a high-speed screen-film system, (4) a specially designed cassette-holder and grid, (5) a breast-shield, and (6) additional filtration in the x-ray tube the thyroid, breast, and abdominal areas were made on an Alderson phantom. They revealed an eightfold reduction in abdominal exposure for both the posteroanterior and the lateral radiographys. There was a twentyfold reduction in exposure to the thyroid for the posteroanterior radiography from 100 to less than five milliroentgensmore » and for the lateral radiograph there was a 100-fold reduction from 618 to six milliroentgens. For the breasts there was a sixty-ninefold reduction from 344 to less than five milliroentgens for the posteroanterior radiography and a fifty-fivefold reduction from 277 to less than five milliroentgens for the lateral radiograph. These reductions in exposure were obtained without significant loss in the quality of the radiographs and in most instances with an improvement in the over-all quality of the radiograph due to the more uniform exposure.« less

Applications of Neutron Radiography for the Nuclear Power Industry

NASA Astrophysics Data System (ADS)

Craft, Aaron E.; Barton, John P.

The World Conference on Neutron Radiography (WCNR) and International Topical Meeting on Neutron Radiography (ITMNR) series have been running over 35 years. The most recent event, ITMNR-8, focused on industrial applications and was the first time this series was hosted in China. In China, more than twenty new nuclear power plants are under construction and plans have been announced to increase the nuclear capacity by a factor of three within fifteen years. There are additional prospects in many other nations. Neutron tests were vital during previous developments of materials and components for nuclear power applications, as reported in the WCNR and ITMNR conference series. For example a majority of the 140 papers in the Proceedings of the First WCNR are for the benefit of the nuclear power industry. Many of those techniques are being utilized and advanced to the present time. Neutron radiography of irradiated nuclear fuel provides more comprehensive information about the internal condition of irradiated nuclear fuel than any other non-destructive technique to date. Applications include examination of nuclear waste, nuclear fuels, cladding, control elements, and other critical components. In this paper, applications of neutron radiography techniques developed and applied internationally for the nuclear power industry since the earliest years are reviewed, and the question is asked whether neutron test techniques, in general, can be of value in development of the present and future generations of nuclear power plants world-wide.

Electron radiography

DOEpatents

Merrill, Frank E.; Morris, Christopher

2005-05-17

A system capable of performing radiography using a beam of electrons. Diffuser means receive a beam of electrons and diffuse the electrons before they enter first matching quadrupoles where the diffused electrons are focused prior to the diffused electrons entering an object. First imaging quadrupoles receive the focused diffused electrons after the focused diffused electrons have been scattered by the object for focusing the scattered electrons. Collimator means receive the scattered electrons and remove scattered electrons that have scattered to large angles. Second imaging quadrupoles receive the collimated scattered electrons and refocus the collimated scattered electrons and map the focused collimated scattered electrons to transverse locations on an image plane representative of the electrons' positions in the object.

Pilot Study of Bovine Interdigital Cassetteless Computed Radiography

PubMed Central

EL-SHAFAEY, El-Sayed Ahmed Awad; AOKI, Takahiro; ISHII, Mitsuo; YAMADA, Kazutaka

2013-01-01

ABSTRACT Twenty-one limbs of bovine cadavers (42 digits) were exposed to interdigital cassetteless imaging plate using computed radiography. The radiographic findings included exostosis, a rough planta surface, osteolysis of the apex of the distal phalanx and widening of the laminar zone between the distal phalanx and the hoof wall. All these findings were confirmed by computed tomography. The hindlimbs (19 digits) showed more changes than the forelimbs (10 digits), particularly in the lateral distal phalanx. The cassetteless computed radiography technique is expected to be an easily applicable method for the distal phalanx rather than a conventional cassette-plate and/or the film-screen cassetteless methods. PMID:23782542

Impact of digital radiography on clinical workflow.

PubMed

May, G A; Deer, D D; Dackiewicz, D

2000-05-01

It is commonly accepted that digital radiography (DR) improves workflow and patient throughput compared with traditional film radiography or computed radiography (CR). DR eliminates the film development step and the time to acquire the image from a CR reader. In addition, the wide dynamic range of DR is such that the technologist can perform the quality-control (QC) step directly at the modality in a few seconds, rather than having to transport the newly acquired image to a centralized QC station for review. Furthermore, additional workflow efficiencies can be achieved with DR by employing tight radiology information system (RIS) integration. In the DR imaging environment, this provides for patient demographic information to be automatically downloaded from the RIS to populate the DR Digital Imaging and Communications in Medicine (DICOM) image header. To learn more about this workflow efficiency improvement, we performed a comparative study of workflow steps under three different conditions: traditional film/screen x-ray, DR without RIS integration (ie, manual entry of patient demographics), and DR with RIS integration. This study was performed at the Cleveland Clinic Foundation (Cleveland, OH) using a newly acquired amorphous silicon flat-panel DR system from Canon Medical Systems (Irvine, CA). Our data show that DR without RIS results in substantial workflow savings over traditional film/screen practice. There is an additional 30% reduction in total examination time using DR with RIS integration.

Josephson junction as the receiving and measuring element in panoramic receiver: frequencymeter in terahertz band

NASA Astrophysics Data System (ADS)

Denisov, Alexander; Gudkov, Alexander; Qiu, Jing Hui

2014-10-01

Josephson junction (JJ) can be used as the criterion in single-block super wide band frequency-meter and as the sensitive element in the super wide band panoramic receiver. There presented the theoretical and experimental investigations and described the innovation decision about to combine both devices in one new microwave device. JJ in this case works in self-pump mode regime. New device can be especially convenient for the experimental purposes with new generation structures when radiated power is small and frequency are unknown correctly.

What can be seen after rotator cuff repair: a brief review of diagnostic imaging findings.

PubMed

Barile, A; Bruno, F; Mariani, S; Arrigoni, F; Reginelli, A; De Filippo, M; Zappia, M; Splendiani, A; Di Cesare, E; Masciocchi, C

2017-03-01

Diagnostic imaging plays an important role in the postoperative evaluation of the rotator cuff, as pain and disability may occur or persist after treatment. Postoperative imaging is therefore of paramount importance for clinicians before planning additional treatments. Multimodality imaging of the postoperative shoulder includes radiography, magnetic resonance (MR) imaging, MR arthrography, computed tomography (CT), CT arthrography, and ultrasound. Correct interpretation of imaging findings of the postoperative shoulder necessitates that the radiologist be familiar with the various treatment strategies, their possible complications and sources of failure, knowledge of normal and abnormal postoperative findings, and awareness of the advantages and weaknesses of the different imaging techniques. Imaging findings, however, should always be correlated with the clinical presentation because postoperative imaging abnormalities do not necessarily correlate with symptoms. This manuscript is a review of some of the most common treatment strategies for rotator cuff pathology, with a focus on expected postoperative imaging findings and postoperative complications.

Comparison of the diagnostic value of ultrasonography and standing radiography for pelvic-femoral disorders in horses.

PubMed

Geburek, Florian; Rötting, Anna K; Stadler, Peter M

2009-04-01

To assess agreement between ultrasonography (transcutaneous and transrectal) and standing radiography in horses with fractures in the pelvic region and disorders of the coxofemoral joint. Case series. Warmblood horses (n=23) and 2 ponies. Medical records (1999-2008) of equids with pelvic or coxofemoral disorders that had pelvic radiography and ultrasonography were retrieved and results of both techniques compared. Radiography and ultrasonography each identified equal numbers of fractures of the tuber coxa (n=4), ilial shaft (2), ischium (3), femoral neck (2), and osteoarthritis/osis of the coxofemoral joint (6). Fractures of the ilial wing (4) were only identified by ultrasonography not by standing radiography. Of 9 acetabular fractures, 3 were identified on radiographs only, 5 were identified with both modalities. One pubic fracture was identified using ultrasonography and radiography. One acetabular and 1 pubic fracture were only diagnosed on necropsy. We found reasonable agreement (73%; 24/33) between ultrasonography and standing radiography for diagnosis of pelvic-femoral disorders. Ultrasonography was more useful for ilial wing fractures and radiography for acetabular fractures. Ultrasonography is a rapid, safe imaging technique for detecting disorders of the pelvic region with a high diagnostic yield and is a preferred initial approach in horses with severe hindlimb lameness.

Dentomaxillofacial characteristics of ectodermal dysplasia.

PubMed

Nakayama, Yumiko; Baba, Yoshiyuki; Tsuji, Michiko; Fukuoka, Hiroki; Ogawa, Takuya; Ohkuma, Mizue; Moriyama, Keiji

2015-02-01

The aim of this retrospective hospital-based study was to elucidate the dentomaxillofacial characteristics of ectodermal dysplasia. Six Japanese individuals (one male and five female; age range, 12.7-27.2 years) underwent comprehensive examinations, including history recording, cephalometric analysis, panoramic radiography, and analysis of dental models. All the subjects had two or more major manifestations for clinical diagnosis of ectodermal dysplasia (e.g., defects of hair, teeth, nails, and sweat glands). They presented hypodontia (mean number of missing teeth, 9.5; range, 5-14), especially in the premolar region, and enamel dysplasia. Five subjects had bilateral molar occlusion, whereas one subject had unilateral molar occlusion. The common skeletal features were small facial height, maxillary hypoplasia, counterclockwise rotation of the mandible, and mandibular protrusion. Interestingly, the maxillary first molars were located in higher positions and the upper anterior facial height was smaller than the Japanese norm. The results suggest that vertical and anteroposterior maxillary growth retardation, rather than lack of occlusal support due to hypodontia, leads to reduced anterior facial height in individuals with ectodermal dysplasia. © 2014 Japanese Teratology Society.

Geometrical modeling of complete dental shapes by using panoramic X-ray, digital mouth data and anatomical templates.

PubMed

Barone, Sandro; Paoli, Alessandro; Razionale, Armando Viviano

2015-07-01

In the field of orthodontic planning, the creation of a complete digital dental model to simulate and predict treatments is of utmost importance. Nowadays, orthodontists use panoramic radiographs (PAN) and dental crown representations obtained by optical scanning. However, these data do not contain any 3D information regarding tooth root geometries. A reliable orthodontic treatment should instead take into account entire geometrical models of dental shapes in order to better predict tooth movements. This paper presents a methodology to create complete 3D patient dental anatomies by combining digital mouth models and panoramic radiographs. The modeling process is based on using crown surfaces, reconstructed by optical scanning, and root geometries, obtained by adapting anatomical CAD templates over patient specific information extracted from radiographic data. The radiographic process is virtually replicated on crown digital geometries through the Discrete Radon Transform (DRT). The resulting virtual PAN image is used to integrate the actual radiographic data and the digital mouth model. This procedure provides the root references on the 3D digital crown models, which guide a shape adjustment of the dental CAD templates. The entire geometrical models are finally created by merging dental crowns, captured by optical scanning, and root geometries, obtained from the CAD templates. Copyright © 2015 Elsevier Ltd. All rights reserved.

Prevalence of dental anomalies on panoramic radiographs in a population of the state of Pará, Brazil.

PubMed

Goncalves-Filho, Antonio Jg; Moda, Larissa B; Oliveira, Roberta P; Ribeiro, Andre Luis Ribeiro; Pinheiro, João Jv; Alver-Junior, S Rgio M

2014-01-01

Dental anomalies (DAs) are the result of disorders that are able to modify the shape, number, size, and structure of teeth. This study aimed to evaluate the prevalence of DAs using panoramic radiographs in a population of the City of Belém, northern Brazil. In this study, 487 panoramic radiographs were evaluated searching for DAs. Dental records were reviewed for diagnostic confirmation. DAs related to the shape, number, size, and structure of teeth were investigated. Our results showed a DA prevalence of 56.9%. The most prevalent DA was taurodontism, which was present in 27.19% of cases. Root dilaceration was the second most prevalent DA in adults, whereas hypodontia was the second most prevalent DA in children. A total of 13 DAs were found. Dental anomalies were present in over half of the sample, and most of them were related to the shape of the teeth. Although there was a high prevalence of shape-related DAs, these alterations are generally of lower severity, and most do not require specific treatment. However, in 19.25% of cases, DAs were found involving the number, size and structure of the teeth. These DAs should be diagnosed and treated early, avoiding thus more serious complications.

A new star tracker concept for satellite attitude determination based on a multi-purpose panoramic camera

NASA Astrophysics Data System (ADS)

Opromolla, Roberto; Fasano, Giancarmine; Rufino, Giancarlo; Grassi, Michele; Pernechele, Claudio; Dionisio, Cesare

2017-11-01

This paper presents an innovative algorithm developed for attitude determination of a space platform. The algorithm exploits images taken from a multi-purpose panoramic camera equipped with hyper-hemispheric lens and used as star tracker. The sensor architecture is also original since state-of-the-art star trackers accurately image as many stars as possible within a narrow- or medium-size field-of-view, while the considered sensor observes an extremely large portion of the celestial sphere but its observation capabilities are limited by the features of the optical system. The proposed original approach combines algorithmic concepts, like template matching and point cloud registration, inherited from the computer vision and robotic research fields, to carry out star identification. The final aim is to provide a robust and reliable initial attitude solution (lost-in-space mode), with a satisfactory accuracy level in view of the multi-purpose functionality of the sensor and considering its limitations in terms of resolution and sensitivity. Performance evaluation is carried out within a simulation environment in which the panoramic camera operation is realistically reproduced, including perturbations in the imaged star pattern. Results show that the presented algorithm is able to estimate attitude with accuracy better than 1° with a success rate around 98% evaluated by densely covering the entire space of the parameters representing the camera pointing in the inertial space.

Imaging Algorithms for Evaluating Suspected Rotator Cuff Disease: Society of Radiologists in Ultrasound Consensus Conference Statement

PubMed Central

Jacobson, Jon A.; Benson, Carol B.; Bancroft, Laura W.; Bedi, Asheesh; McShane, John M.; Miller, Theodore T.; Parker, Laurence; Smith, Jay; Steinbach, Lynne S.; Teefey, Sharlene A.; Thiele, Ralf G.; Tuite, Michael J.; Wise, James N.; Yamaguchi, Ken

2013-01-01

The Society of Radiologists in Ultrasound convened a panel of specialists from a variety of medical disciplines to reach a consensus about the recommended imaging evaluation of painful shoulders with clinically suspected rotator cuff disease. The panel met in Chicago, Ill, on October 18 and 19, 2011, and created this consensus statement regarding the roles of radiography, ultrasonography (US), computed tomography (CT), CT arthrography, magnetic resonance (MR) imaging, and MR arthrography. The consensus panel consisted of two co-moderators, a facilitator, a statistician and health care economist, and 10 physicians who have specialty expertise in shoulder pain evaluation and/or treatment. Of the 13 physicians on the panel, nine were radiologists who were chosen to represent a broad range of skill sets in diagnostic imaging, different practice types (private and academic), and different geographical regions of the United States. Five of the radiologists routinely performed musculoskeletal US as part of their practice and four did not. There was also one representative from each of the following clinical specialties: rheumatology, physical medicine and rehabilitation, orthopedic surgery, and nonoperative sports medicine. The goal of this conference was to construct several algorithms with which to guide the imaging evaluation of suspected rotator cuff disease in patients with a native rotator cuff, patients with a repaired rotator cuff, and patients who have undergone shoulder replacement. The panel hopes that these recommendations will lead to greater uniformity in rotator cuff imaging and more cost-effective care for patients suspected of having rotator cuff abnormality. © RSNA, 2013 PMID:23401583

Characterization of optically stimulated luminescence dosemeters to measure organ doses in diagnostic radiology

PubMed Central

Endo, A; Katoh, T; Kobayashi, I; Joshi, R; Sur, J; Okano, T

2012-01-01

Objective The aim of this study was to assess the characteristics of an optically stimulated luminescence dosemeter (OSLD) for use in diagnostic radiology and to apply the OSLD in measuring the organ doses by panoramic radiography. Methods The dose linearity, energy dependency and angular dependency of aluminium oxide-based OSLDs were examined using an X-ray generator to simulate various exposure settings in diagnostic radiology. The organ doses were then measured by inserting the dosemeters into an anthropomorphic phantom while using three panoramic machines. Results The dosemeters demonstrated consistent dose linearity (coefficient of variation<1.5%) and no significant energy dependency (coefficient of variation<1.5%) under the applied exposure conditions. They also exhibited negligible angular dependency (≤10%). The organ doses of the X-ray as a result of panoramic imaging by three machines were calculated using the dosemeters. Conclusion OSLDs can be utilized to measure the organ doses in diagnostic radiology. The availability of these dosemeters in strip form proves to be reliably advantageous. PMID:22116136

Study of pipe thickness loss using a neutron radiography method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mohamed, Abdul Aziz; Wahab, Aliff Amiru Bin; Yazid, Hafizal B.

2014-02-12

The purpose of this preliminary work is to study for thickness changes in objects using neutron radiography. In doing the project, the technique for the radiography was studied. The experiment was done at NUR-2 facility at TRIGA research reactor in Malaysian Nuclear Agency, Malaysia. Test samples of varying materials were used in this project. The samples were radiographed using direct technique. Radiographic images were recorded using Nitrocellulose film. The films obtained were digitized to processed and analyzed. Digital processing is done on the images using software Isee!. The images were processed to produce better image for analysis. The thickness changesmore » in the image were measured to be compared with real thickness of the objects. From the data collected, percentages difference between measured and real thickness are below than 2%. This is considerably very low variation from original values. Therefore, verifying the neutron radiography technique used in this project.« less

Combining Public Domain and Professional Panoramic Imagery for the Accurate and Dense 3d Reconstruction of the Destroyed Bel Temple in Palmyra

NASA Astrophysics Data System (ADS)

Wahbeh, W.; Nebiker, S.; Fangi, G.

2016-06-01

This paper exploits the potential of dense multi-image 3d reconstruction of destroyed cultural heritage monuments by either using public domain touristic imagery only or by combining the public domain imagery with professional panoramic imagery. The focus of our work is placed on the reconstruction of the temple of Bel, one of the Syrian heritage monuments, which was destroyed in September 2015 by the so called "Islamic State". The great temple of Bel is considered as one of the most important religious buildings of the 1st century AD in the East with a unique design. The investigations and the reconstruction were carried out using two types of imagery. The first are freely available generic touristic photos collected from the web. The second are panoramic images captured in 2010 for documenting those monuments. In the paper we present a 3d reconstruction workflow for both types of imagery using state-of-the art dense image matching software, addressing the non-trivial challenges of combining uncalibrated public domain imagery with panoramic images with very wide base-lines. We subsequently investigate the aspects of accuracy and completeness obtainable from the public domain touristic images alone and from the combination with spherical panoramas. We furthermore discuss the challenges of co-registering the weakly connected 3d point cloud fragments resulting from the limited coverage of the touristic photos. We then describe an approach using spherical photogrammetry as a virtual topographic survey allowing the co-registration of a detailed and accurate single 3d model of the temple interior and exterior.

A method to optimize the processing algorithm of a computed radiography system for chest radiography.

PubMed

Moore, C S; Liney, G P; Beavis, A W; Saunderson, J R

2007-09-01

A test methodology using an anthropomorphic-equivalent chest phantom is described for the optimization of the Agfa computed radiography "MUSICA" processing algorithm for chest radiography. The contrast-to-noise ratio (CNR) in the lung, heart and diaphragm regions of the phantom, and the "system modulation transfer function" (sMTF) in the lung region, were measured using test tools embedded in the phantom. Using these parameters the MUSICA processing algorithm was optimized with respect to low-contrast detectability and spatial resolution. Two optimum "MUSICA parameter sets" were derived respectively for maximizing the CNR and sMTF in each region of the phantom. Further work is required to find the relative importance of low-contrast detectability and spatial resolution in chest images, from which the definitive optimum MUSICA parameter set can then be derived. Prior to this further work, a compromised optimum MUSICA parameter set was applied to a range of clinical images. A group of experienced image evaluators scored these images alongside images produced from the same radiographs using the MUSICA parameter set in clinical use at the time. The compromised optimum MUSICA parameter set was shown to produce measurably better images.

First steps towards real-time radiography at the NECTAR facility

NASA Astrophysics Data System (ADS)

Bücherl, T.; Wagner, F. M.; v. Gostomski, Ch. Lierse

2009-06-01

The beam tube SR10 at Forschungsneutronenquelle Heinz Maier-Leibnitz (FRM II) provides an intense beam of fission neutrons for medical application (MEDAPP) and for radiography and tomography of technical and other objects (NECTAR). The high neutron flux of up to 9.8E+07 cm -2 s -1 (depending on filters and collimation) with a mean energy of about 1.9 MeV at the sample position at the NECTAR facility prompted an experimental feasibility study to investigate the potential for real-time (RT) radiography.

Impact of age-related macular degeneration on object searches in realistic panoramic scenes.

PubMed

Thibaut, Miguel; Tran, Thi-Ha-Chau; Szaffarczyk, Sebastien; Boucart, Muriel

2018-05-01

This study investigated whether realistic immersive conditions with dynamic indoor scenes presented on a large, hemispheric panoramic screen covering 180° of the visual field improved the visual search abilities of participants with age-related macular degeneration (AMD). Twenty-one participants with AMD, 16 age-matched controls and 16 young observers were included. Realistic indoor scenes were presented on a panoramic five metre diameter screen. Twelve different objects were used as targets. The participants were asked to search for a target object, shown on paper before each trial, within a room composed of various objects. A joystick was used for navigation within the scene views. A target object was present in 24 trials and absent in 24 trials. The percentage of correct detection of the target, the percentage of false alarms (that is, the detection of the target when it was absent), the number of scene views explored and the search time were measured. The search time was slower for participants with AMD than for the age-matched controls, who in turn were slower than the young participants. The participants with AMD were able to accomplish the task with a performance of 75 per cent correct detections. This was slightly lower than older controls (79.2 per cent) while young controls were at ceiling (91.7 per cent). Errors were mainly due to false alarms resulting from confusion between the target object and another object present in the scene in the target-absent trials. The outcomes of the present study indicate that, under realistic conditions, although slower than age-matched, normally sighted controls, participants with AMD were able to accomplish visual searches of objects with high accuracy. © 2017 Optometry Australia.

Detection failure rate of chest radiography for the identification of nursing and healthcare-associated pneumonia.

PubMed

Miyashita, Naoyuki; Kawai, Yasuhiro; Tanaka, Takaaki; Akaike, Hiroto; Teranishi, Hideto; Wakabayashi, Tokio; Nakano, Takashi; Ouchi, Kazunobu; Okimoto, Niro

2015-07-01

To clarify the detection failure rate of chest radiography for the identification of nursing and healthcare-associated pneumonia (NHCAP), we compared high-resolution computed tomography (HRCT) with chest radiography simultaneously for patients with clinical symptoms and signs leading to a suspicion of NHCAP. We analyzed 208 NHCAP cases and compared them based on four groups defined using NHCAP criteria, patients who were: Group A) resident in an extended care facility or nursing home; Group B) discharged from a hospital within the preceding 90 days; Group C) receiving nursing care and had poor performance status; and Group D) receiving regular endovascular treatment. Chest radiography was inferior to HRCT for the identification of pneumonia (149 vs 208 cases, p < 0.0001). Among the designated NHCAP criteria, chest radiography identified pneumonia cases at a significantly lower frequency than HRCT in Group A (70 vs 97 cases, p = 0.0190) and Group C (86 vs 136 cases, p < 0.0001). The detection failure rate of chest radiography differed among NHCAP criteria; 27.8% in Group A, 26.5% in Group B, 36.7% in Group C and 5.8% in Group D. Cerebrovascular disease and poor functional status were significantly more frequent in patients in Groups A and C compared with those in Groups B and D. Physicians may underestimate pneumonia shadow in chest radiographs in patients with NHCAP, and the detection failure rate of chest radiography differed among NHCAP criteria. Poor functional status may correlate with the low accuracy of chest radiography in diagnosing pneumonia. Copyright © 2015. Published by Elsevier Ltd.

Using three-dimensional-computerized tomography as a diagnostic tool for temporo-mandibular joint ankylosis: a case report.

PubMed

Kao, S Y; Chou, J; Lo, J; Yang, J; Chou, A P; Joe, C J; Chang, R C

1999-04-01

Roentgenographic examination has long been a useful diagnostic tool for temporo-mandibular joint (TMJ) disease. The methods include TMJ tomography, panoramic radiography and computerized tomography (CT) scan with or without injection of contrast media. Recently, three-dimensional CT (3D-CT), reconstructed from the two-dimensional image of a CT scan to simulate the soft tissue or bony structure of the real target, was proposed. In this report, a case of TMJ ankylosis due to traumatic injury is presented. 3D-CT was employed as one of the presurgical roentgenographic diagnostic tools. The conventional radiographic examination including panoramic radiography and tomography showed lesions in both sides of the mandible. CT scanning further suggested that the right-sided lesion was more severe than that on the left. With 3D-CT image reconstruction the size and extent of the lesions were clearly observable. The decision was made to proceed with an initial surgical approach on the right side. With condylectomy and condylar replacement using an autogenous costochondral graft on the right side, the range of mouth opening improved significantly. In this case report, 3D-CT demonstrates its advantages as a tool for the correct and precise diagnosis of TMJ ankylosis.

Effect of Localizer Radiography Projection on Organ Dose at Chest CT with Automatic Tube Current Modulation.

PubMed

Saltybaeva, Natalia; Krauss, Andreas; Alkadhi, Hatem

2017-03-01

Purpose To calculate the effect of localizer radiography projections to the total radiation dose, including both the dose from localizer radiography and that from subsequent chest computed tomography (CT) with tube current modulation (TCM). Materials and Methods An anthropomorphic phantom was scanned with 192-section CT without and with differently sized breast attachments. Chest CT with TCM was performed after one localizer radiographic examination with anteroposterior (AP) or posteroanterior (PA) projections. Dose distributions were obtained by means of Monte Carlo simulations based on acquired CT data. For Monte Carlo simulations of localizer radiography, the tube position was fixed at 0° and 180°; for chest CT, a spiral trajectory with TCM was used. The effect of tube start angles on dose distribution was investigated with Monte Carlo simulations by using TCM curves with fixed start angles (0°, 90°, and 180°). Total doses for lungs, heart, and breast were calculated as the sum of the dose from localizer radiography and CT. Image noise was defined as the standard deviation of attenuation measured in 14 circular regions of interest. The Wilcoxon signed rank test, paired t test, and Friedman analysis of variance were conducted to evaluate differences in noise, TCM curves, and organ doses, respectively. Results Organ doses from localizer radiography were lower when using a PA instead of an AP projection (P = .005). The use of a PA projection resulted in higher TCM values for chest CT (P < .001) owing to the higher attenuation (P < .001) and thus resulted in higher total organ doses for all investigated phantoms and protocols (P < .001). Noise in CT images was lower with PA localizer radiography than with AP localizer radiography (P = .03). The use of an AP projection allowed for total dose reductions of 16%, 15%, and 12% for lungs, breast, and heart, respectively. Differences in organ doses were not related to tube start angles (P = .17). Conclusion The total

Effect of comfort pads and incubator design on neonatal radiography.

PubMed

Jiang, Xia; Baad, Michael; Reiser, Ingrid; Feinstein, Kate A; Lu, Zhengfeng

2016-01-01

There has been increasing interest in patient dose reduction in neonatal intensive care units. Removing comfort pads for radiography has been identified as a potential means to decrease patient dose. To assess the effect of comfort pads and support trays on detector entrance exposure (DEE) and image quality for neonatal radiography, and its implication for patient dose. Comfort pads and support trays from three incubator and warmer systems were examined. The attenuation of the primary beam by these structures was measured using a narrow beam geometry. Their effect on DEE and image quality was then assessed using typical neonatal chest radiography techniques with three configurations: 1) both the comfort pad and support included in the beam, 2) only the support tray included and 3) both the comfort pad and support tray removed. Comfort pads and support trays were found to attenuate the primary beam by 6-15%. Eliminating these structures from the X-ray beam's path was found to increase the detector entrance exposure by 28-36% and increase contrast-to-noise ratio by more than 21%, suggesting room for patient dose reduction when the same image quality is maintained. Comfort pads and tray support devices can have a considerable effect on DEE and image quality, with large variations among different incubator designs. Positioning the image detector directly underneath neonatal patients for radiography is a potential means for patient dose reduction. However, such benefit should be weighed against the risks of moving the patient.

Searching early bone metastasis on plain radiography by using digital imaging processing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jaramillo-Nunez, A.; Perez-Meza, M.; Universidad de la Sierra Sur, C. P. 70800, Miahuatlan, Oax.

2012-10-23

Some authors mention that it is not possible to detect early bone metastasis on plain radiography. In this work we use digital imaging processing to analyze three radiographs taken from a patient with bone metastasis discomfort on the right shoulder. The time period among the first and second radiography was approximately one month and between the first and the third one year. This procedure is a first approach in order to know if in this particular case it was possible to detect an early bone metastasis. The obtained results suggest that by carrying out a digital processing is possible tomore » detect the metastasis since the radiography contains the information although visually it is not possible to observe it.« less

[Detection of lung nodules. New opportunities in chest radiography].

PubMed

Pötter-Lang, S; Schalekamp, S; Schaefer-Prokop, C; Uffmann, M

2014-05-01

Chest radiography still represents the most commonly performed X-ray examination because it is readily available, requires low radiation doses and is relatively inexpensive. However, as previously published, many initially undetected lung nodules are retrospectively visible in chest radiographs. The great improvements in detector technology with the increasing dose efficiency and improved contrast resolution provide a better image quality and reduced dose needs. The dual energy acquisition technique and advanced image processing methods (e.g. digital bone subtraction and temporal subtraction) reduce the anatomical background noise by reduction of overlapping structures in chest radiography. Computer-aided detection (CAD) schemes increase the awareness of radiologists for suspicious areas. The advanced image processing methods show clear improvements for the detection of pulmonary lung nodules in chest radiography and strengthen the role of this method in comparison to 3D acquisition techniques, such as computed tomography (CT). Many of these methods will probably be integrated into standard clinical treatment in the near future. Digital software solutions offer advantages as they can be easily incorporated into radiology departments and are often more affordable as compared to hardware solutions.

Ultrafast table-top dynamic radiography of spontaneous or stimulated events

DOEpatents

Smilowitz, Laura; Henson, Bryan

2018-01-16

Disclosed herein are representative embodiments of methods, apparatus, and systems for performing radiography. For example, certain embodiments concern X-ray radiography of spontaneous events. Particular embodiments of the disclosed technology provide continuous high-speed x-ray imaging of spontaneous dynamic events, such as explosions, reaction-front propagation, and even material failure. Further, in certain embodiments, x-ray activation and data collection activation are triggered by the object itself that is under observation (e.g., triggered by a change of state detected by one or more sensors monitoring the object itself).

Implementation of a PACS for radiography training and clinical service in a university setting through a multinational effort

NASA Astrophysics Data System (ADS)

Tang, Fuk-hay; Law, Yuen Y.; Zhang, Jianguo; Liu, Hai L.; Chang, Tony; Matsuda, Koyo; Cao, Fei

2001-08-01

The Hong Kong Polytechnic University has a Radiography Division under the Development of Optometry and Radiography. The Division trains both diagnostic and therapeutic radiographers with 60 students/year and offers a B.Sc. degree. In addition the Division together with the University Health Service operates a radiography clinic with radiology consultation from radiologists from other hospitals and clinics. This paper describers the implementation of a PACS in the Division for radiography training, and for clinical service.

Integrating dynamic stereo-radiography and surface-based motion data for subject-specific musculoskeletal dynamic modeling.

PubMed

Zheng, Liying; Li, Kang; Shetye, Snehal; Zhang, Xudong

2014-09-22

This manuscript presents a new subject-specific musculoskeletal dynamic modeling approach that integrates high-accuracy dynamic stereo-radiography (DSX) joint kinematics and surface-based full-body motion data. We illustrate this approach by building a model in OpenSim for a patient who participated in a meniscus transplantation efficacy study, incorporating DSX data of the tibiofemoral joint kinematics. We compared this DSX-incorporated (DSXI) model to a default OpenSim model built using surface-measured data alone. The architectures and parameters of the two models were identical, while the differences in (time-averaged) tibiofemoral kinematics were of the order of magnitude of 10° in rotation and 10mm in translation. Model-predicted tibiofemoral compressive forces and knee muscle activations were compared against literature data acquired from instrumented total knee replacement components (Fregly et al., 2012) and the patient's EMG recording. The comparison demonstrated that the incorporation of DSX data improves the veracity of musculoskeletal dynamic modeling. Copyright © 2014 Elsevier Ltd. All rights reserved.

Integrating dynamic stereo-radiography and surface-based motion data for subject-specific musculoskeletal dynamic modeling

PubMed Central

Zheng, Liying; Li, Kang; Shetye, Snehal; Zhang, Xudong

2014-01-01

This paper presents a new subject-specific musculoskeletal dynamic modeling approach that integrates high-accuracy dynamic stereo-radiography (DSX) joint kinematics and surface-based full-body motion data. We illustrate this approach by building a model in OpenSim for a patient who participated in a meniscus transplantation efficacy study, incorporating DSX data of the tibiofemoral joint kinematics. We compared this DSX-incorporated (DSXI) model to a default OpenSim model built using surface-measured data alone. The architectures and parameters of the two models were identical, while the differences in (time-averaged) tibiofemoral kinematics were of the order of magnitude of 10° in rotation and 10 mm in translation. Model-predicted tibiofemoral compressive forces and knee muscle activations were compared against literature data acquired from instrumented total knee replacement components (Fregly et al., 2012) and the patient's EMG recording. The comparison demonstrated that the incorporation of DSX data improves the veracity of musculoskeletal dynamic modeling. PMID:25169658

Thoracic radiography in the cat: Identification of cardiomegaly and congestive heart failure.

PubMed

Guglielmini, Carlo; Diana, Alessia

2015-12-01

Thoracic radiography is one of the most commonly employed diagnostic tools for the clinical evaluation of cats with suspected heart disease and is the standard diagnostic method in the confirmation of cardiogenic pulmonary edema. In the past, interpretation of feline radiographs focused on a description of the qualitative radiographic features of feline heart disease or the measurement of the cardiac silhouette in healthy cats and cats with different cardiovascular disorders. More recently, studies have begun to critically address the issue of the diagnostic accuracy of thoracic radiography in the diagnostic work-up of cats with heart disease. In these studies, qualitative and quantitative radiographic parameters were compared to echocardiographic findings to evaluate the usefulness of thoracic radiography for the identification of cardiac enlargement and pulmonary edema in the cat. Thoracic radiography is reasonably specific but has a low sensitivity when identifying cardiomegaly in cats with mild structural heart disease. Feline cardiogenic pulmonary edema has a variable radiographic presentation and several specific radiographic findings (i.e., enlargement of the left atrium and the pulmonary veins) can be absent or non-recognizable in affected cats. Copyright © 2015 Elsevier B.V. All rights reserved.

Radiography on wheels arrives to nursing homes - an economic assessment of a new health care technology in southern Sweden.

PubMed

Dozet, Alexander; Ivarsson, Bodil; Eklund, Karin; Klefsgård, Rosemarie; Geijer, Mats

2016-12-01

The process of transferring older, vulnerable adults from an elder care facility to the hospital for medical care can be an emotionally and physically stressful experience. The recent development of modern mobile radiography may help to ease this anxiety by allowing for evaluation in the nursing home itself. Up until this point, no health economic evaluation of the technology has been attempted in a Swedish setting. The objective of this study was to determine whether examinations of patients in elder care facilities with mobile radiography were cost-effective from a societal perspective compared with hospital-based radiological examinations. This prospective study included two groups of nursing home residents in two different areas in southern Sweden. All residents in the nursing homes were targeted for the study. Seventy-one patients were examined with hospital-based radiography at two hospitals, and 312 patients were examined using mobile radiography in nursing homes. Given that the diagnostic effects are regarded as equivalent, a cost minimization method was applied. Direct costs were estimated using prices from the county council, Region Skåne, Sweden. From a societal perspective, mobile radiography was shown to have significantly lower costs per examination compared with hospital-based radiography. The difference in health care-related costs was also significant in favour of mobile radiography. Mobile radiography can be used to examine patients in nursing homes at a lower cost than hospital-based radiography. Patients benefit from not having to transfer to a hospital for radiography, resulting in reduced anxiety for patients. © 2016 John Wiley & Sons, Ltd.

A comparison of digital tomosynthesis and chest radiography in evaluating airway lesions using computed tomography as a reference.

PubMed

Choo, Ji Yung; Lee, Ki Yeol; Yu, Ami; Kim, Je-Hyeong; Lee, Seung Heon; Choi, Jung Won; Kang, Eun-Young; Oh, Yu Whan

2016-09-01

To compare the diagnostic performance of digital tomosynthesis (DTS) and chest radiography for detecting airway abnormalities, using computed tomography (CT) as a reference. We evaluated 161 data sets from 149 patients (91 with and 70 without airway abnormalities) who had undergone radiography, DTS, and CT to detect airway problems. Radiographs and DTS were evaluated to localize and score the severity of the airway abnormalities, and to score the image quality using CT as a reference. Receiver operating characteristics (ROC), McNemar's test, weighted kappa, and the paired t-test were used for statistical analysis. The sensitivity of DTS was higher (reader 1, 93.51 %; reader 2, 94.29 %) than chest radiography (68.83 %; 71.43 %) in detecting airway lesions. The diagnostic accuracy of DTS (90.91 %; 94.70 %) was also significantly better than that of radiography (78.03 %; 82.58 %, all p < 0.05). DTS image quality was significantly better than chest radiography (1.83, 2.74; p < 0.05) in the results of both readers. The inter-observer agreement with respect to DTS findings was moderate and superior when compared to radiography findings. DTS is a more accurate and sensitive modality than radiography for detecting airway lesions that are easily obscured by soft tissue structures in the mediastinum. • Digital tomosynthesis offers new diagnostic options for airway lesions. • Digital tomosynthesis is more sensitive and accurate than radiography for airway lesions. • Digital tomosynthesis shows better image quality than radiography. • Assessment of lesion severity, via tomosynthesis is comparable to computed tomography.

Rib Radiography versus Chest Computed Tomography in the Diagnosis of Rib Fractures.

PubMed

Sano, Atsushi

2018-05-01

 The accurate diagnosis of rib fractures is important in chest trauma. Diagnostic images following chest trauma are usually obtained via chest X-ray, chest computed tomography, or rib radiography. This study evaluated the diagnostic characteristics of rib radiography and chest computed tomography.  Seventy-five rib fracture patients who underwent both chest computed tomography and rib radiography between April 2008 and December 2013 were included. Rib radiographs, centered on the site of pain, were taken from two directions. Chest computed tomography was performed using a 16-row multidetector scanner with 5-mm slice-pitch without overlap, and axial images were visualized in a bone window.  In total, 217 rib fractures were diagnosed in 75 patients. Rib radiography missed 43 rib fractures in 24 patients. The causes were overlap with organs in 15 cases, trivial fractures in 21 cases, and injury outside the imaging range in 7 cases. Left lower rib fractures were often missed due to overlap with the heart, while middle and lower rib fractures were frequently not diagnosed due to overlap with abdominal organs. Computed tomography missed 21 rib fractures in 17 patients. The causes were horizontal fractures in 10 cases, trivial fractures in 9 cases, and insufficient breath holding in 1 case.  In rib radiography, overlap with organs and fractures outside the imaging range were characteristic reasons for missed diagnoses. In chest computed tomography, horizontal rib fractures and insufficient breath holding were often responsible. We should take these challenges into account when diagnosing rib fractures. Georg Thieme Verlag KG Stuttgart · New York.

Use of radiography in acute knee injuries: need for clinical decision rules.

PubMed

Stiell, I G; Wells, G A; McDowell, I; Greenberg, G H; McKnight, R D; Cwinn, A A; Quinn, J V; Yeats, A

1995-11-01

To study: 1) the efficiency of the current use of radiography in acute knee injuries, 2) the judgments and attitudes of experienced clinicians in their use of knee radiography, and 3) the potential for decision rules to improve efficiency. This two-stage study of adults with acute knee injuries involved: 1) a retrospective review of all 1,967 patients seen over a 12-month period in the EDs of one community and two teaching hospital, and 2) a prospective survey of another 1,040 patients seen by attending emergency physicians. The prospective survey assessed each clinician's estimate of the probability of a knee or patella fracture; 120 patients were independently assessed by two physicians. Of the 1,967 patients seen in the first stage, 74.1% underwent radiography but only 5.2% were found to have fractures. Of the 1,727 knee and patella radiographic series ordered, 92.4% were negative for fracture. In the second stage, experienced physicians predicted the probability of fracture to be 0 or 0.1 for 75.6% of the patients. The kappa value for this response was 0.51 (95% CI 0.34 to 0.68). The physicians also indicated that they would have been comfortable or very comfortable in not ordering radiography for 55.5% of the patients. The area under the receiver operating characteristics curve for the physicians' prediction of fracture was 0.87 (95% CI 0.82 to 0.91), reflecting good discrimination between fracture and nonfracture cases. Likelihood ratios for the physicians' prediction ranged from 0.09 at the 0 level to 42.9 at the 0.9-1.0 level. Emergency physicians order radiography for most patients with acute knee injuries, even though they can accurately discriminate between fracture and nonfracture cases and expect most of the radiographs to be normal. These findings suggest great potential for more efficient use of knee radiography, possibly through the use of a clinical decision rule.

Emergency physicians' attitudes toward and use of clinical decision rules for radiography.

PubMed

Graham, I D; Stiell, I G; Laupacis, A; O'Connor, A M; Wells, G A

1998-02-01

1) To assess Canadian emergency physicians' (EPs') use of and attitudes toward 2 radiographic clinical decision rules that have recently been developed and to identify physician characteristics associated with decision rule use; 2) to determine the use of CT head and cervical spine radiography by EPs and their beliefs about the appropriateness of expert recommendations supporting the routine use of these radiographic procedures; and 3) to determine the potential acceptance of clinical decision rules for CT scan in patients with minor head injury and cervical spine radiography in trauma patients. A cross-sectional anonymous mail survey of a random sample of 300 members of the Canadian Association of Emergency Physicians using Dillman's Total Design Method for mail surveys. Of 288 eligible physicians, 232 (81%) responded. More than 95% of the respondents stated they currently used the Ottawa Ankle Rules and were willing to consider using the newly developed Ottawa Knee Rule. Physician characteristics related to frequent use of the Ottawa Ankle Rules were younger age, fewer years since graduating from medical school, part time or resident employment status, working in a hospital without a CT scanner, and believing that decision rules are not oversimplified cookbook medicine or too rigid to apply. Eighty-five percent did not agree that all patients with minor head injuries should receive a CT head scan and only 3.5% stated they always refer such patients for CT scan. Similarly, 78.5% of the respondents did not agree that all trauma patients should receive cervical spine radiography and only 13.2% said they always refer such patients for cervical spine radiography. Ninety-seven and 98% stated they would be willing to consider using well-validated decision rules for CT scan of the head and cervical spine radiography, respectively. Fifty-two percent and 67% of the respondents required the proposed CT and C-spine to be 100% sensitive for identifying serious injuries

Infection control practices for dental radiography.

PubMed

Palenik, Charles John

2004-06-01

Infection control for dental radiography employs the same materials, processes, and techniques used in the operatory, yet unless proper procedures are established and followed, there is a definite potential for cross-contamination to clinical area surfaces and DHCP. In general, the aseptic practices used are relatively simple and inexpensive, yet they require complete application in every situation.

Videoscopic assessment of the maintenance status of gamma radiography exposure containers employed in Brazil.

PubMed

Candeias, J P; Estrada, J J S; Pinho, A S; D'Avila, R L; Ramalho, A T

2007-03-01

Industrial radiography is the most frequent method of non-destructive testing (NDT) used by Brazilian industrial facilities for investigating the material integrity of a test object. In Brazil, industrial radiography employs around 220 x-ray and 290 gamma radiography machines. About 90% of the latter uses iridium ((192)Ir) sources. The large majority of (192)Ir projectors in operation in Brazil have been in continuous usage for more than 25 years, which means that they are old and worn-out. Usually the majority of accidents concerning gamma radiography occur during the return of the source into the exposure container. Poor maintenance or imperfections of the internal channel of the exposure container can lead to accidental source exposure. In the present work the internal tube of 65 gamma machines from nine Brazilian companies that render gamma radiography services were analysed using an industrial videoscope. The internal images from the projectors were compared with the internal image of an apparatus that had never been used, i.e. has never received a radioactive source. From the 65 machines evaluated, nine showed irregularities of the internal tube. It was also observed that each company follows a different methodology for the maintenance and lubrication of the exposure containers and drive cables.

Intramodality and intermodality agreement in radiography and computed tomography of equine distal limb fractures.

PubMed

Crijns, C P; Martens, A; Bergman, H-J; van der Veen, H; Duchateau, L; van Bree, H J J; Gielen, I M V L

2014-01-01

Computed tomography (CT) is increasingly accessible in equine referral hospitals. To document the level of agreement within and between radiography and CT in characterising equine distal limb fractures. Retrospective descriptive study. Images from horses that underwent radiographic and CT evaluation for suspected distal limb fractures were reviewed, including 27 horses and 3 negative controls. Using Cohen's kappa and weighted kappa analysis, the level of agreement among 4 observers for a predefined set of diagnostic characteristics for radiography and CT separately and for the level of agreement between the 2 imaging modalities were documented. Both CT and radiography had very good intramodality agreement in identifying fractures, but intermodality agreement was lower. There was good intermodality and intramodality agreement for anatomical localisation and the identification of fracture displacement. Agreement for articular involvement, fracture comminution and fracture fragment number was towards the lower limit of good agreement. There was poor to fair intermodality agreement regarding fracture orientation, fracture width and coalescing cracks; intramodality agreement was higher for CT than for radiography for these features. Further studies, including comparisons with surgical and/or post mortem findings, are required to determine the sensitivity and specificity of CT and radiography in the diagnosis and characterisation of equine distal limb fractures. © 2013 EVJ Ltd.

Investigating the use of an antiscatter grid in chest radiography for average adults with a computed radiography imaging system

PubMed Central

Wood, T J; Avery, G; Balcam, S; Needler, L; Smith, A; Saunderson, J R; Beavis, A W

2015-01-01

Objective: The aim of this study was to investigate via simulation a proposed change to clinical practice for chest radiography. The validity of using a scatter rejection grid across the diagnostic energy range (60–125 kVp), in conjunction with appropriate tube current–time product (mAs) for imaging with a computed radiography (CR) system was investigated. Methods: A digitally reconstructed radiograph algorithm was used, which was capable of simulating CR chest radiographs with various tube voltages, receptor doses and scatter rejection methods. Four experienced image evaluators graded images with a grid (n = 80) at tube voltages across the diagnostic energy range and varying detector air kermas. These were scored against corresponding images reconstructed without a grid, as per current clinical protocol. Results: For all patients, diagnostic image quality improved with the use of a grid, without the need to increase tube mAs (and therefore patient dose), irrespective of the tube voltage used. Increasing tube mAs by an amount determined by the Bucky factor made little difference to image quality. Conclusion: A virtual clinical trial has been performed with simulated chest CR images. Results indicate that the use of a grid improves diagnostic image quality for average adults, without the need to increase tube mAs, even at low tube voltages. Advances in knowledge: Validated with images containing realistic anatomical noise, it is possible to improve image quality by utilizing grids for chest radiography with CR systems without increasing patient exposure. Increasing tube mAs by an amount determined by the Bucky factor is not justified. PMID:25571914

Comparison of Digital Imaging Systems for Neutron Radiography

NASA Astrophysics Data System (ADS)

Pugliesi, R.; Pugliesi, Fábio; Stanojev Pereira, M. A.

2011-09-01

The characteristics of three digital imaging systems for neutron radiography purposes have been compared. Two of them make use of films, CR-39 and Kodak AA, and the third makes use of a LiF scintillator, for image registration. The irradiations were performed in the neutron radiography facility installed at the IEA-R1 nuclear research reactor of IPEN-CNEN/SP. According to the obtained results, the system based on CR-39 is the slowest to obtain an image, and the best in terms of resolution but the worse in terms of contrast. The system based on Kodak AA is faster than the prior, exhibits good resolution and contrast. The system based on the scintillator is the fastest to obtain an image, and best in terms of contrast but the worse in terms of resolution.

Multispectral scanner system for ERTS: Four band scanner system. Volume 2: Engineering model panoramic pictures and engineering tests

NASA Technical Reports Server (NTRS)

1972-01-01

This document is Volume 2 of three volumes of the Final Report for the four band Multispectral Scanner System (MSS). The results are contained of an analysis of pictures of actual outdoor scenes imaged by the engineering model MSS for spectral response, resolution, noise, and video correction. Also included are the results of engineering tests on the MSS for reflectance and saturation from clouds. Finally, two panoramic pictures of Yosemite National Park are provided.

Tomosynthesis for the early detection of pulmonary emphysema: diagnostic performance compared with chest radiography, using multidetector computed tomography as reference.

PubMed

Yamada, Yoshitake; Jinzaki, Masahiro; Hashimoto, Masahiro; Shiomi, Eisuke; Abe, Takayuki; Kuribayashi, Sachio; Ogawa, Kenji

2013-08-01

To compare the diagnostic performance of tomosynthesis with that of chest radiography for the detection of pulmonary emphysema, using multidetector computed tomography (MDCT) as reference. Forty-eight patients with and 63 without pulmonary emphysema underwent chest MDCT, tomosynthesis and radiography on the same day. Two blinded radiologists independently evaluated the tomosynthesis images and radiographs for the presence of pulmonary emphysema. Axial and coronal MDCT images served as the reference standard and the percentage lung volume with attenuation values of -950 HU or lower (LAA-950) was evaluated to determine the extent of emphysema. Receiver-operating characteristic (ROC) analysis and generalised estimating equations model were used. ROC analysis revealed significantly better performance (P < 0.0001) of tomosynthesis than radiography for the detection of pulmonary emphysema. The average sensitivity, specificity, positive predictive value and negative predictive value of tomosynthesis were 0.875, 0.968, 0.955 and 0.910, respectively, whereas the values for radiography were 0.479, 0.913, 0.815 and 0.697, respectively. For both tomosynthesis and radiography, the sensitivity increased with increasing LAA-950. The diagnostic performance of tomosynthesis was significantly superior to that of radiography for the detection of pulmonary emphysema. In both tomosynthesis and radiography, the sensitivity was affected by the LAA-950. • Tomosynthesis showed significantly better diagnostic performance for pulmonary emphysema than radiography. • Interobserver agreement for tomosynthesis was significantly higher than that for radiography. • Sensitivity increased with increasing LAA -950 in both tomosynthesis and radiography. • Tomosynthesis imparts a similar radiation dose to two projection chest radiography. • Radiation dose and cost of tomosynthesis are lower than those of MDCT.

INDUSTRIAL RADIOGRAPHY COURSE, INSTRUCTORS' GUIDE. VOLUME 2.

ERIC Educational Resources Information Center

Texas A and M Univ., College Station. Engineering Extension Service.

INFORMATION RELATIVE TO THE LESSON PLANS IN "INDUSTRIAL RADIOGRAPHY COURSE, INSTRUCTOR'S GUIDE, VOLUME I" (VT 003 565) IS PRESENTED ON 52 INFORMATION SHEETS INCLUDING THE SUBJECTS SHIELDING EQUATIONS AND LOGARITHMS, METAL PROPERTIES, FIELD TRIP INSTRUCTIONS FOR STUDENTS, WELDING SYMBOLS AND SIZES, SAMPLE REPORT FORMS, AND TYPICAL SHIPPING…

Use of digital abdominal radiography for the diagnosis of enterolithiasis in equids: 238 cases (2008-2011).

PubMed

Kelleher, Maureen E; Puchalski, Sarah M; Drake, Christiana; le Jeune, Sarah S

2014-07-01

To evaluate the sensitivity and specificity of direct digital abdominal radiography for the diagnosis of enterolithiasis in equids and to assess the effect of the number and anatomic location of enteroliths and gas distention of the gastrointestinal tract on diagnostic sensitivity of the technique. Retrospective case series. 238 horses and ponies ≥ 1 year old that underwent digital abdominal radiography with subsequent exploratory celiotomy or postmortem examination. For each case, 3 reviewers independently evaluated radiographic views. Radiographic images were evaluated for presence or absence and location of enteroliths and the degree of gas distention. Signalment, definitive diagnosis based on exploratory celiotomy or postmortem examination findings, and number and anatomic location of enteroliths were obtained from the medical records. 70 of the 238 (29.4%) equids had confirmed enterolithiasis. With regard to diagnosis of enterolithiasis via digital radiography, overall sensitivity and specificity for the 3 reviewers were 84% and 96%, respectively. Sensitivity was lower for small colon enteroliths (61.5%) than for large colon enteroliths (88.9%) and was negatively affected by gas distention of the gastrointestinal tract. Sensitivity was not affected by the number of enteroliths. Sensitivity and specificity of digital radiography for the diagnosis of large colon enterolithiasis in equids was high. Sensitivity of digital radiography for detection of small colon enteroliths was lower than that for large colon enteroliths, but was higher than that typically associated with computed radiography. In geographic regions in which enterolithiasis in equids is endemic, digital abdominal radiography could be used as a diagnostic test for equids with colic.

Patient doses from chest radiography in Victoria.

PubMed

Cardillo, I; Boal, T J; Einsiedel, P F

1997-06-01

This survey examines doses from PA chest radiography at radiology practices, private hospitals and public hospitals throughout metropolitan and country Victoria. Data were collected from 111 individual X-ray units at 86 different practices. Entrance skin doses in air were measured for exposure factors used by the centre for a 23 cm thick male chest. A CDRH LucA1 chest phantom was used when making these measurements. About half of the centres used grid technique and half used non-grid technique. There was a factor of greater than 10 difference in the entrance dose delivered between the highest dose centre and the lowest dose centre for non-grid centres; and a factor of about 5 for centres using grids. Factors contributing to the high doses recorded at some centres were identified. Guidance levels for chest radiography based on the third quartile value of the entrance doses from this survey have been recommended and compared with guidance levels recommended in other countries.

Responses of neurons in the medial column of the inferior olive in pigeons to translational and rotational optic flowfields.

PubMed

Winship, I R; Wylie, D R

2001-11-01

The responses of neurons in the medial column of the inferior olive to translational and rotational optic flow were recorded from anaesthetized pigeons. Panoramic translational or rotational flowfields were produced by mechanical devices that projected optic flow patterns onto the walls, ceiling and floor of the room. The axis of rotation/translation could be positioned to any orientation in three-dimensional space such that axis tuning could be determined. Each neuron was assigned a vector representing the axis about/along which the animal would rotate/translate to produce the flowfield that elicited maximal modulation. Both translation-sensitive and rotation-sensitive neurons were found. For neurons responsive to translational optic flow, the preferred axis is described with reference to a standard right-handed coordinate system, where +x, +y and +z represent rightward, upward and forward translation of the animal, respectively (assuming that all recordings were from the right side of the brain). t(+y) neurons were maximally excited in response to a translational optic flowfield that results from self-translation upward along the vertical (y) axis. t(-y) neurons also responded best to translational optic flow along the vertical axis but showed the opposite direction preference. The two remaining groups, t(-x+z) and t(-x-z) neurons, responded best to translational optic flow along horizontal axes that were oriented 45 degrees to the midline. There were two types of neurons responsive to rotational optic flow: rVA neurons preferred rotation about the vertical axis, and rH135c neurons preferred rotation about a horizontal axis at 135 degrees contralateral azimuth. The locations of marking lesions indicated a clear topographical organization of the six response types. In summary, our results reinforce that the olivo-cerebellar system dedicated to the analysis of optic flow is organized according to a reference frame consisting of three approximately orthogonal axes

Electrode Slurry Particle Density Mapping Using X-ray Radiography

DOE PAGES

Higa, Kenneth; Zhao, Hui; Parkinson, Dilworth Y.; ...

2017-01-05

The internal structure of a porous electrode strongly influences battery performance. Understanding the dynamics of electrode slurry drying could aid in engineering electrodes with desired properties. For instance, one might monitor the dynamic, spatially-varying thickness near the edge of a slurry coating, as it should lead to non-uniform thickness of the dried film. This work examines the dynamic behavior of drying slurry drops consisting of SiO x and carbon black particles in a solution of carboxymethylcellulose and deionized water, as an experimental model of drying behavior near the edge of a slurry coating. An X-ray radiography-based procedure is developed tomore » calculate the evolving spatial distribution of active material particles from images of the drying slurry drops. To the authors’ knowledge, this study is the first to use radiography to investigate battery slurry drying, as well as the first to determine particle distributions from radiography images of drying suspensions. The dynamic results are consistent with tomography reconstructions of the static, fully-dried films. It is found that active material particles can rapidly become non-uniformly distributed within the drops. Heating can promote distribution uniformity, but seemingly must be applied very soon after slurry deposition. Higher slurry viscosity is found to strongly restrain particle redistribution.« less

High Resolution Neutron Radiography and Tomography of Hydrided Zircaloy-4 Cladding Materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, Tyler S; Bilheux, Hassina Z; Ray, Holly B

2015-01-01

Neutron radiography for hydrogen analysis was performed with several Zircaloy-4 cladding samples with controlled hydrogen concentrations up to 1100 ppm. Hydrogen charging was performed in a process tube that was heated to facilitate hydrogen absorption by the metal. A correlation between the hydrogen concentration in the hydrided tubes and the neutron intensity was established, by which hydrogen content can be determined precisely in a small area (55 m x 55 m). Radiography analysis was also performed to evaluate the heating rate and its correlation with the hydrogen distribution through hydrided materials. In addition to radiography analysis, tomography experiments were performedmore » on Zircaloy-4 tube samples to study the local hydrogen distribution. Through tomography analysis a 3D reconstruction of the tube was evaluated in which an uneven hydrogen distribution in the circumferential direction can be observed.« less

Spatial resolution measurements of the advanced radiographic capability x-ray imaging system at energies relevant to Compton radiography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hall, G. N.; Izumi, N.; Landen, O. L.

2016-08-03

Compton radiography provides a means to measure the integrity, ρR and symmetry of the DT fuel in an inertial confinement fusion implosion near peak compression. Upcoming experiments at the National Ignition Facility will use the ARC (Advanced Radiography Capability) laser to drive backlighter sources for Compton radiography experiments, and will use the newly commissioned AXIS (ARC X-ray Imaging System) instrument as the detector. AXIS uses a dual-MCP (micro channel plate) to provide gating and high DQE at the 40–200keV x-ray range required for Compton radiography, but introduces many effects that contribute to the spatial resolution. Here, experiments were performed atmore » energies relevant to Compton radiography to begin characterization of the spatial resolution of the AXIS diagnostic.« less

Comparison of radiation dose, workflow, patient comfort and financial break-even of standard digital radiography and a novel biplanar low-dose X-ray system for upright full-length lower limb and whole spine radiography.

PubMed

Dietrich, Tobias J; Pfirrmann, Christian W A; Schwab, Alexander; Pankalla, Katja; Buck, Florian M

2013-07-01

To compare the radiation dose, workflow, patient comfort, and financial break-even of a standard digital radiography and a biplanar low-dose X-ray system. A standard digital radiography system (Ysio, Siemens Healthcare, Erlangen, Germany) was compared with a biplanar X-ray unit (EOS, EOS imaging, Paris, France) consisting of two X-ray tubes and slot-scanning detectors, arranged at an angle of 90° allowing simultaneous vertical biplanar linear scanning in the upright patient position. We compared data of standing full-length lower limb radiographs and whole spine radiographs of both X-ray systems. Dose-area product was significantly lower for radiographs of the biplanar X-ray system than for the standard digital radiography system (e.g. whole spine radiographs; standard digital radiography system: 392.2 ± 231.7 cGy*cm(2) versus biplanar X-ray system: 158.4 ± 103.8 cGy*cm(2)). The mean examination time was significantly shorter for biplanar radiographs compared with standard digital radiographs (e.g. whole spine radiographs: 449 s vs 248 s). Patients' comfort regarding noise was significantly higher for the standard digital radiography system. The financial break-even point was 2,602 radiographs/year for the standard digital radiography system compared with 4,077 radiographs/year for the biplanar X-ray unit. The biplanar X-ray unit reduces radiation exposure and increases subjective noise exposure to patients. The biplanar X-ray unit demands a higher number of examinations per year for the financial break-even point, despite the lower labour cost per examination due to the shorter examination time.

An automated technique to stage lower third molar development on panoramic radiographs for age estimation: a pilot study.

PubMed

De Tobel, J; Radesh, P; Vandermeulen, D; Thevissen, P W

2017-12-01

Automated methods to evaluate growth of hand and wrist bones on radiographs and magnetic resonance imaging have been developed. They can be applied to estimate age in children and subadults. Automated methods require the software to (1) recognise the region of interest in the image(s), (2) evaluate the degree of development and (3) correlate this to the age of the subject based on a reference population. For age estimation based on third molars an automated method for step (1) has been presented for 3D magnetic resonance imaging and is currently being optimised (Unterpirker et al. 2015). To develop an automated method for step (2) based on lower third molars on panoramic radiographs. A modified Demirjian staging technique including ten developmental stages was developed. Twenty panoramic radiographs per stage per gender were retrospectively selected for FDI element 38. Two observers decided in consensus about the stages. When necessary, a third observer acted as a referee to establish the reference stage for the considered third molar. This set of radiographs was used as training data for machine learning algorithms for automated staging. First, image contrast settings were optimised to evaluate the third molar of interest and a rectangular bounding box was placed around it in a standardised way using Adobe Photoshop CC 2017 software. This bounding box indicated the region of interest for the next step. Second, several machine learning algorithms available in MATLAB R2017a software were applied for automated stage recognition. Third, the classification performance was evaluated in a 5-fold cross-validation scenario, using different validation metrics (accuracy, Rank-N recognition rate, mean absolute difference, linear kappa coefficient). Transfer Learning as a type of Deep Learning Convolutional Neural Network approach outperformed all other tested approaches. Mean accuracy equalled 0.51, mean absolute difference was 0.6 stages and mean linearly weighted kappa was

Tooth coronal index and pulp/tooth ratio in dental age estimation on digital panoramic radiographs-A comparative study.

PubMed

Jain, Supreet; Nagi, Ravleen; Daga, Minal; Shandilya, Ashutosh; Shukla, Aastha; Parakh, Abhinav; Laheji, Afshan; Singh, Rahul

2017-08-01

Assessment of an age of an individual whether living or dead through teeth is one of the most reliable and simple method to calculate age than skeletal remains especially when they are in poor conditions. The study was carried out with aim of (i) to evaluate reliability of dental age assessment through two different methods for adults i.e. tooth coronal index and pulp/tooth ratio using digital panoramic radiographs and (ii) to compare these methods for their accuracy in age determination. The digital panoramic radiographs of 180 subjects of Chhattisgarh aged 15-70 years were selected for the study. The measurements were performed on the JPEG images of selected panoramic radiographs by using Adobe Acrobat 7.0 professional software. For tooth coronal index (TCI), height of the crown i.e. coronal height (CH) and the height of the coronal pulp cavity i.e. coronal pulp cavity height (CPCH) of mandibular second premolars and first molars was measured in millimeter (mm) and then TCI was calculated for each tooth and calculated age was compared with chronological age. For pulp/tooth ratio, the measurements of pulp chamber height (PCH) and crown root trunk height (CRTH) were performed on the mandibular first and second molar teeth, the pulp chamber crown root trunk height ratios (PCTHR) of selected tooth were calculated. The acquired data were subjected to Pearson correlation test, unpaired t test and Analysis of Variance (ANOVA) analysis. Results suggested that TCI (mandibular first molar r=-0.178), second premolar (r=-0.187) and PCTHR(mandibular first molar r=-0.921, second molar r=-0.901) correlated negatively with chronological age suggesting decrease in size of pulp cavity. Mandibular first molar was found to be most reliable tooth to estimate dental age. The study showed that both PCTHR and TCI have negative association with chronological age. PCTHR showed slightly higher negative correlation and proved as a better tool for age estimation than TCI. Statistically

Dual Use Corrosion Inhibitor and Penetrant for Anomaly Detection in Neutron/X Radiography

NASA Technical Reports Server (NTRS)

Hall, Phillip B. (Inventor); Novak, Howard L. (Inventor)

2004-01-01

A dual purpose corrosion inhibitor and penetrant composition sensitive to radiography interrogation is provided. The corrosion inhibitor mitigates or eliminates corrosion on the surface of a substrate upon which the corrosion inhibitor is applied. In addition, the corrosion inhibitor provides for the attenuation of a signal used during radiography interrogation thereby providing for detection of anomalies on the surface of the substrate.

Retrospective comparison of abdominal ultrasonography and radiography in the investigation of feline abdominal disease

PubMed Central

Won, Wylen Wade; Sharma, Ajay; Wu, Wenbo

2015-01-01

Abdominal radiography and ultrasonography are commonly used as part of the initial diagnostic plan for cats with nonspecific signs of abdominal disease. This retrospective study compared the clinical usefulness of abdominal radiography and ultrasonography in 105 feline patients with signs of abdominal disease. The final diagnosis was determined more commonly with ultrasonography (59%) compared to radiography (25.7%). Ultrasonography was also able to provide additional clinically relevant information in 76% of cases, and changed or refined the diagnosis in 47% of cases. Based on these findings, ultrasonography may be sufficient as an initial diagnostic test for the investigation of feline abdominal disease. PMID:26483582

Impact of Clinical Decision Support on Radiography for Acute Ankle Injuries: A Randomized Trial

PubMed Central

Tajmir, Shahein; Raja, Ali S.; Ip, Ivan K.; Andruchow, James; Silveira, Patricia; Smith, Stacy; Khorasani, Ramin

2017-01-01

Introduction While only 15–20% of patients with foot and ankle injuries presenting to urgent care centers have clinically significant fractures, most undergo radiography. We examined the impact of electronic point-of-care clinical decision support (CDS) on adherence to the Ottawa Ankle Rules (OAR), as well as use and yield of foot and ankle radiographs in patients with acute ankle injury. Methods We obtained institutional review board approval for this randomized controlled study performed April 18, 2012—December 15, 2013. All ordering providers credentialed at an urgent care affiliated with a quaternary care academic hospital were randomized to either receive or not receive CDS, based on the OAR and integrated into the physician order-entry system, with feedback at the time of imaging order. If the patient met OAR low-risk criteria, providers were advised against imaging and could either cancel the order or ignore the alert. We identified patients with foot and ankle complaints via ICD-9 billing codes and electronic health records and radiology reports reviewed for those who were eligible. Chi-square was used to compare adherence to the OAR (primary outcome), radiography utilization rate and radiography yield of foot and ankle imaging (secondary outcomes) between the intervention and control groups. Results Of 14,642 patients seen at urgent care during the study period, 613 (4.2%, representing 632 visits) presented with acute ankle injury and were eligible for application of the OAR; 374 (59.2%) of these were seen by control-group providers. In the intervention group, CDS adherence was higher for both ankle (239/258=92.6% vs. 231/374=61.8%, p=0.02) and foot radiography (209/258=81.0% vs. 238/374=63.6%; p<0.01). However, ankle radiography use was higher in the intervention group (166/258=64.3% vs. 183/374=48.9%; p<0.01), while foot radiography use (141/258=54.6% vs. 202/374=54.0%; p=0.95) was not. Radiography yield was also higher in the intervention group (26

Immersive Virtual Moon Scene System Based on Panoramic Camera Data of Chang'E-3

NASA Astrophysics Data System (ADS)

Gao, X.; Liu, J.; Mu, L.; Yan, W.; Zeng, X.; Zhang, X.; Li, C.

2014-12-01

The system "Immersive Virtual Moon Scene" is used to show the virtual environment of Moon surface in immersive environment. Utilizing stereo 360-degree imagery from panoramic camera of Yutu rover, the system enables the operator to visualize the terrain and the celestial background from the rover's point of view in 3D. To avoid image distortion, stereo 360-degree panorama stitched by 112 images is projected onto inside surface of sphere according to panorama orientation coordinates and camera parameters to build the virtual scene. Stars can be seen from the Moon at any time. So we render the sun, planets and stars according to time and rover's location based on Hipparcos catalogue as the background on the sphere. Immersing in the stereo virtual environment created by this imaged-based rendering technique, the operator can zoom, pan to interact with the virtual Moon scene and mark interesting objects. Hardware of the immersive virtual Moon system is made up of four high lumen projectors and a huge curve screen which is 31 meters long and 5.5 meters high. This system which take all panoramic camera data available and use it to create an immersive environment, enable operator to interact with the environment and mark interesting objects contributed heavily to establishment of science mission goals in Chang'E-3 mission. After Chang'E-3 mission, the lab with this system will be open to public. Besides this application, Moon terrain stereo animations based on Chang'E-1 and Chang'E-2 data will be showed to public on the huge screen in the lab. Based on the data of lunar exploration，we will made more immersive virtual moon scenes and animations to help the public understand more about the Moon in the future.

Panoramic Electrophysiological Mapping but not Electrogram Morphology Identifies Stable Sources for Human Atrial Fibrillation

PubMed Central

Narayan, Sanjiv M.; Shivkumar, Kalyanam; Krummen, David E.; Miller, John M.; Rappel, Wouter-Jan

2013-01-01

Background The foundation for successful arrhythmia ablation is the mapping of electric propagation to identify underlying mechanisms. In atrial fibrillation (AF), however, mapping is difficult so that ablation has often targeted electrogram features, with mixed results. We hypothesized that wide field-of-view (panoramic) mapping of both atria would identify causal mechanisms for AF and allow interpretation of local electrogram features, including complex fractionated atrial electrograms (CFAE). Methods and Results Contact mapping was performed using biatrial multipolar catheters in 36 AF subjects (29 persistent). Stable AF rotors (spiral waves) or focal sources were seen in 35 of 36 cases and targeted for ablation (focal impulse and rotor modulation) before pulmonary vein isolation. In 31 of 36 subjects (86.1%), AF acutely terminated (n=20; 16 to sinus rhythm) or organized (n=11; 19±8% slowing) with 2.5 minutes focal impulse and rotor modulation (interquartile range, 1.0–3.1) at one source, defined as the primary source. Subjects exhibited 2.1±1.0 concurrent AF sources of which the primary, by phase mapping, precessed in limited areas (persistent 2.5±1.7 versus paroxysmal 1.7±0.5 cm2; P=0.30). Notably, source regions showed mixed electrogram amplitudes and CFAE grades that did not differ from surrounding atrium (P=NS). AF sources were not consistently surrounded by CFAE (P=0.67). Conclusions Stable rotors and focal sources for human AF were revealed by contact panoramic mapping (focal impulse and rotor modulation mapping), but not by electrogram footprints. AF sources precessed within areas of ≈2 cm2, with diverse voltage characteristics poorly correlated with CFAE. Most CFAE sites lie remote from AF sources and are not suitable targets for catheter ablation of AF. PMID:23392583

Can Chest Computed Tomography Be Replaced by Lung Ultrasonography With or Without Plain Chest Radiography in Pediatric Pneumonia?

PubMed

Hajalioghli, Parisa; Nemati, Masoud; Dinparast Saleh, Leila; Fouladi, Daniel F

2016-07-01

The purpose of this study was to answer the following question: can chest computed tomography (CT) requested by pediatricians be replaced by lung ultrasonography (US) with or without chest radiography in pediatric pneumonia? A total of 98 children with suspected pneumonia who were referred by pediatricians for CT examinations were prospectively studied. Levels of agreement between CT findings and plain radiography, lung US, and chest radiography plus lung US results were investigated. CT defined pneumonia in 84 patients, among which 26 cases were complicated. κ values between radiography and CT findings were 0.82 in complicated cases, 0.67 in uncomplicated cases, and 0.72 overall. The corresponding values between US and CT findings were 1, 0.52, and 0.62, respectively, and between radiography plus US and CT findings were 1, 0.86, and 0.88, respectively. CT can be replaced by US when complex effusions are present in children with pneumonia. In case of an ambiguous diagnosis of pediatric pneumonia with or without complex effusions, a combination of chest radiography and US is a reliable surrogate for chest CT.

The frequency of various indications for plain chest radiography in Nnamdi Azikiwe University Teaching Hospital, Nnewi (NAUTH).

PubMed

Okpala, O C; Okafor, C; Aronu, M E

2013-01-01

With soaring advances in the field of medicine, the place of older radiologic imaging modalities is being reduced to basic screening tools. Yet the modern imaging modalities like computerized tomography (CT), magnetic resonance imaging (MRI), ultrasound and nuclear medicine are hardly available. To study the frequency of various indications of plain chest radiography, remind us of its uses and to enhance the preparedness of the department to maximally accomplish the ideals of this investigation. A total of 1476 consecutive patients for chest radiography in the department of radiology, NAUTH, Nnewi from the period of February 2009 and whose request form contain adequate data were recruited for this study. These data were analyzed using SSPS. A total of 1476 patient were included in this study. There was female preponderance with male to female ratio of 1.3:1. Mean Age of the patients is 39.32 years (std19.56). The most frequent indication for chest radiography is certain infections and parasitic diseases (40.9% and the greatest source of referral for this study is General outpatient (GOPD)/family medicine department. The most frequent indications for chest radiography in the study are certain infection and parasitic diseases. Chest Radiography is the most frequent plain radiography study in our environment where infectious diseases are still very rampant. This makes chest radiography an important study for screening patient for possible diagnosis and classifying the need for further radiographic investigation of our patients.

Registration of pencil beam proton radiography data with X-ray CT.

PubMed

Deffet, Sylvain; Macq, Benoît; Righetto, Roberto; Vander Stappen, François; Farace, Paolo

2017-10-01

Proton radiography seems to be a promising tool for assessing the quality of the stopping power computation in proton therapy. However, range error maps obtained on the basis of proton radiographs are very sensitive to small misalignment between the planning CT and the proton radiography acquisitions. In order to be able to mitigate misalignment in postprocessing, the authors implemented a fast method for registration between pencil proton radiography data obtained with a multilayer ionization chamber (MLIC) and an X-ray CT acquired on a head phantom. The registration was performed by optimizing a cost function which performs a comparison between the acquired data and simulated integral depth-dose curves. Two methodologies were considered, one based on dual orthogonal projections and the other one on a single projection. For each methodology, the robustness of the registration algorithm with respect to three confounding factors (measurement noise, CT calibration errors, and spot spacing) was investigated by testing the accuracy of the method through simulations based on a CT scan of a head phantom. The present registration method showed robust convergence towards the optimal solution. For the level of measurement noise and the uncertainty in the stopping power computation expected in proton radiography using a MLIC, the accuracy appeared to be better than 0.3° for angles and 0.3 mm for translations by use of the appropriate cost function. The spot spacing analysis showed that a spacing larger than the 5 mm used by other authors for the investigation of a MLIC for proton radiography led to results with absolute accuracy better than 0.3° for angles and 1 mm for translations when orthogonal proton radiographs were fed into the algorithm. In the case of a single projection, 6 mm was the largest spot spacing presenting an acceptable registration accuracy. For registration of proton radiography data with X-ray CT, the use of a direct ray-tracing algorithm to compute

Video Completion in Digital Stabilization Task Using Pseudo-Panoramic Technique

NASA Astrophysics Data System (ADS)

Favorskaya, M. N.; Buryachenko, V. V.; Zotin, A. G.; Pakhirka, A. I.

2017-05-01

Video completion is a necessary stage after stabilization of a non-stationary video sequence, if it is desirable to make the resolution of the stabilized frames equalled the resolution of the original frames. Usually the cropped stabilized frames lose 10-20% of area that means the worse visibility of the reconstructed scenes. The extension of a view of field may appear due to the pan-tilt-zoom unwanted camera movement. Our approach deals with a preparing of pseudo-panoramic key frame during a stabilization stage as a pre-processing step for the following inpainting. It is based on a multi-layered representation of each frame including the background and objects, moving differently. The proposed algorithm involves four steps, such as the background completion, local motion inpainting, local warping, and seamless blending. Our experiments show that a necessity of a seamless stitching occurs often than a local warping step. Therefore, a seamless blending was investigated in details including four main categories, such as feathering-based, pyramid-based, gradient-based, and optimal seam-based blending.

Third of three panoramic views of North Base as seen ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Third of three panoramic views of North Base as seen from top of Building 4500, Control Tower. View looks west (268°) at ancillary structures surrounding Building 4505. In immediate foreground is Building 4499 Loading Ramp. To the far upper left is Building 4497 Guard House, adjacent to Building 4496 Security Facility. At the extreme right of the view is the chimney and western corner of Building 4505 to which is attached a large light-colored wing used as offices and workspaces; to the immediate southwest of this wing stands Building 4498 Supply Warehouse. In the background, just above Building 4498 in view, stands Building 4494 Cafeteria. The round drum to the right of Building 4494 is Building 4503, a 500,000 gallon water tank which supplies the firefighting system; to the immediate right of the tank is Building 4504 Deluge Water Pumping Station which contains large pumps for firefighting. Just visible above the water tank is Building 4493 Gymnasium. - Edwards Air Force Base, North Base, North Base Road, Boron, Kern County, CA

Flash radiography with 24 GeV/c protons

NASA Astrophysics Data System (ADS)

Morris, C. L.; Ables, E.; Alrick, K. R.; Aufderheide, M. B.; Barnes, P. D.; Buescher, K. L.; Cagliostro, D. J.; Clark, D. A.; Clark, D. J.; Espinoza, C. J.; Ferm, E. N.; Gallegos, R. A.; Gardner, S. D.; Gomez, J. J.; Greene, G. A.; Hanson, A.; Hartouni, E. P.; Hogan, G. E.; King, N. S. P.; Kwiatkowski, K.; Liljestrand, R. P.; Mariam, F. G.; Merrill, F. E.; Morgan, D. V.; Morley, K. B.; Mottershead, C. T.; Murray, M. M.; Pazuchanics, P. D.; Pearson, J. E.; Sarracino, J. S.; Saunders, A.; Scaduto, J.; Schach von Wittenau, A. E.; Soltz, R. A.; Sterbenz, S.; Thompson, R. T.; Vixie, K.; Wilke, M. D.; Wright, D. M.; Zumbro, J. D.

2011-05-01

The accuracy of density measurements and position resolution in flash (40 ns) radiography of thick objects with 24 Gev/c protons is investigated. A global model fit to step wedge data is shown to give a good description spanning the periodic table. The parameters obtained from the step wedge data are used to predict transmission through the French Test Object (FTO), a test object of nested spheres, to a precision better than 1%. Multiple trials have been used to show that the systematic errors are less than 2%. Absolute agreement between the average radiographic measurements of the density and the known density is 1%. Spatial resolution has been measured to be 200 μm at the center of the FTO. These data verify expectations of the benefits provided by high energy hadron radiography for thick objects.

Comparison of radiography and ultrasonography for the diagnosis of osteochondritis dissecans in the equine femoropatellar joint.

PubMed

Bourzac, C; Alexander, K; Rossier, Y; Laverty, S

2009-09-01

Osteochondritis dissecans (OCD) lesions of the femoropatellar (FP) joint are diagnosed routinely by radiography, but lesions located in the trochlear groove or without accompanying subchondral bone changes can be difficult to visualise. Ultrasonography allows evaluation of articular cartilage and subchondral bone in the FPjoint. To document the radiographic and ultrasonographic appearance of OCD lesions in the equine FP joint, grade ultrasonographic lesions and compare their accuracy in the diagnosis of these lesions. The medical records of all horses diagnosed with FP OCD between 1995 and 2006 were assessed. Inclusion criteria included availability of both radiographic and ultrasonographic images. Lesion characteristics were evaluated in each trochlear ridge and trochlear groove. For assessment of the accuracy (sensitivity and specificity) of both imaging techniques in the diagnosis of OCD, only cases with an arthroscopic or necropsy examination were studied. Twenty-one horses were included. OCD lesions were diagnosed by radiography (30/32 joints) and ultrasound (32/32 joints). The lateral trochlear ridge (LTR, 91%) and the medial trochlear ridge (MTR, 17%) were involved on radiography. The localisation on ultrasound examination was similar (97% LTR, 25% MTR). All but one lesion seen on radiography were also detected with ultrasound; 2 LTR and 3 MTR lesions, not seen on radiography were diagnosed by ultrasound and confirmed at arthroscopy or necropsy. The specificity was 100% regardless of the site and imaging procedure except for the distal third of the MTR (94% for ultrasound). The sensitivity varied, depending on lesion site. Ultrasonography is a valuable diagnostic tool to diagnose OCD lesions in the FP joint and more sensitive than radiography for lesions affecting the MTR of the distal femur. Ultrasound should be considered as a useful adjunct to radiography for diagnosing equine FP OCD, especially in cases of high clinical suspicion but equivocal

Correlation of the clinical and physical image quality in chest radiography for average adults with a computed radiography imaging system.

PubMed

Moore, C S; Wood, T J; Beavis, A W; Saunderson, J R

2013-07-01

The purpose of this study was to examine the correlation between the quality of visually graded patient (clinical) chest images and a quantitative assessment of chest phantom (physical) images acquired with a computed radiography (CR) imaging system. The results of a previously published study, in which four experienced image evaluators graded computer-simulated postero-anterior chest images using a visual grading analysis scoring (VGAS) scheme, were used for the clinical image quality measurement. Contrast-to-noise ratio (CNR) and effective dose efficiency (eDE) were used as physical image quality metrics measured in a uniform chest phantom. Although optimal values of these physical metrics for chest radiography were not derived in this work, their correlation with VGAS in images acquired without an antiscatter grid across the diagnostic range of X-ray tube voltages was determined using Pearson's correlation coefficient. Clinical and physical image quality metrics increased with decreasing tube voltage. Statistically significant correlations between VGAS and CNR (R=0.87, p<0.033) and eDE (R=0.77, p<0.008) were observed. Medical physics experts may use the physical image quality metrics described here in quality assurance programmes and optimisation studies with a degree of confidence that they reflect the clinical image quality in chest CR images acquired without an antiscatter grid. A statistically significant correlation has been found between the clinical and physical image quality in CR chest imaging. The results support the value of using CNR and eDE in the evaluation of quality in clinical thorax radiography.

Correlation of the clinical and physical image quality in chest radiography for average adults with a computed radiography imaging system

PubMed Central

Wood, T J; Beavis, A W; Saunderson, J R

2013-01-01

Objective: The purpose of this study was to examine the correlation between the quality of visually graded patient (clinical) chest images and a quantitative assessment of chest phantom (physical) images acquired with a computed radiography (CR) imaging system. Methods: The results of a previously published study, in which four experienced image evaluators graded computer-simulated postero-anterior chest images using a visual grading analysis scoring (VGAS) scheme, were used for the clinical image quality measurement. Contrast-to-noise ratio (CNR) and effective dose efficiency (eDE) were used as physical image quality metrics measured in a uniform chest phantom. Although optimal values of these physical metrics for chest radiography were not derived in this work, their correlation with VGAS in images acquired without an antiscatter grid across the diagnostic range of X-ray tube voltages was determined using Pearson’s correlation coefficient. Results: Clinical and physical image quality metrics increased with decreasing tube voltage. Statistically significant correlations between VGAS and CNR (R=0.87, p<0.033) and eDE (R=0.77, p<0.008) were observed. Conclusion: Medical physics experts may use the physical image quality metrics described here in quality assurance programmes and optimisation studies with a degree of confidence that they reflect the clinical image quality in chest CR images acquired without an antiscatter grid. Advances in knowledge: A statistically significant correlation has been found between the clinical and physical image quality in CR chest imaging. The results support the value of using CNR and eDE in the evaluation of quality in clinical thorax radiography. PMID:23568362

An update on dental imaging.

PubMed

Whaites, E; Brown, J

1998-08-22

This paper reviews recent advances and current trends in dental radiology. Developments in the design of dental x-ray equipment which improve both radiation hygiene and image quality are described. Also discussed are new features which broaden the scope of intra-oral and panoramic radiological diagnosis in the general dental practice setting. The article concludes with the main recommendations from the latest guidelines on quality standards for radiography, selection criteria and quality assurance in general practice.

Clinical evaluation of a mobile digital specimen radiography system for intraoperative specimen verification.

PubMed

Wang, Yingbing; Ebuoma, Lilian; Saksena, Mansi; Liu, Bob; Specht, Michelle; Rafferty, Elizabeth

2014-08-01

Use of mobile digital specimen radiography systems expedites intraoperative verification of excised breast specimens. The purpose of this study was to evaluate the performance of a such a system for verifying targets. A retrospective review included 100 consecutive pairs of breast specimen radiographs. Specimens were imaged in the operating room with a mobile digital specimen radiography system and then with a conventional digital mammography system in the radiology department. Two expert reviewers independently scored each image for image quality on a 3-point scale and confidence in target visualization on a 5-point scale. A target was considered confidently verified only if both reviewers declared the target to be confidently detected. The 100 specimens contained a total of 174 targets, including 85 clips (49%), 53 calcifications (30%), 35 masses (20%), and one architectural distortion (1%). Although a significantly higher percentage of mobile digital specimen radiographs were considered poor quality by at least one reviewer (25%) compared with conventional digital mammograms (1%), 169 targets (97%), were confidently verified with mobile specimen radiography; 172 targets (98%) were verified with conventional digital mammography. Three faint masses were not confidently verified with mobile specimen radiography, and conventional digital mammography was needed for confirmation. One faint mass and one architectural distortion were not confidently verified with either method. Mobile digital specimen radiography allows high diagnostic confidence for verification of target excision in breast specimens across target types, despite lower image quality. Substituting this modality for conventional digital mammography can eliminate delays associated with specimen transport, potentially decreasing surgical duration and increasing operating room throughput.

A maximum likelihood method for high resolution proton radiography/proton CT.

PubMed

Collins-Fekete, Charles-Antoine; Brousmiche, Sébastien; Portillo, Stephen K N; Beaulieu, Luc; Seco, Joao

2016-12-07

Multiple Coulomb scattering (MCS) is the largest contributor to blurring in proton imaging. In this work, we developed a maximum likelihood least squares estimator that improves proton radiography's spatial resolution. The water equivalent thickness (WET) through projections defined from the source to the detector pixels were estimated such that they maximizes the likelihood of the energy loss of every proton crossing the volume. The length spent in each projection was calculated through the optimized cubic spline path estimate. The proton radiographies were produced using Geant4 simulations. Three phantoms were studied here: a slanted cube in a tank of water to measure 2D spatial resolution, a voxelized head phantom for clinical performance evaluation as well as a parametric Catphan phantom (CTP528) for 3D spatial resolution. Two proton beam configurations were used: a parallel and a conical beam. Proton beams of 200 and 330 MeV were simulated to acquire the radiography. Spatial resolution is increased from 2.44 lp cm -1 to 4.53 lp cm -1 in the 200 MeV beam and from 3.49 lp cm -1 to 5.76 lp cm -1 in the 330 MeV beam. Beam configurations do not affect the reconstructed spatial resolution as investigated between a radiography acquired with the parallel (3.49 lp cm -1 to 5.76 lp cm -1 ) or conical beam (from 3.49 lp cm -1 to 5.56 lp cm -1 ). The improved images were then used as input in a photon tomography algorithm. The proton CT reconstruction of the Catphan phantom shows high spatial resolution (from 2.79 to 5.55 lp cm -1 for the parallel beam and from 3.03 to 5.15 lp cm -1 for the conical beam) and the reconstruction of the head phantom, although qualitative, shows high contrast in the gradient region. The proposed formulation of the optimization demonstrates serious potential to increase the spatial resolution (up by 65[Formula: see text]) in proton radiography and greatly accelerate proton computed tomography reconstruction.

Optimization of exposure factors for X-ray radiography non-destructive testing of pearl oyster

NASA Astrophysics Data System (ADS)

Susilo; Yulianti, I.; Addawiyah, A.; Setiawan, R.

2018-03-01

One of the processes in pearl oyster cultivation is detecting the pearl nucleus to gain information whether the pearl nucleus is still attached in the shell or vomited. The common tool used to detect pearl nucleus is an X-ray machine. However, an X-ray machine has a drawback that is the energy used is higher than that used by digital radiography. The high energy make the resulted image is difficult to be analysed. One of the advantages of digital radiography is the energy used can be adjusted so that the resulted image can be analysed easily. To obtain a high quality of pearl image using digital radiography, the exposure factors should be optimized. In this work, optimization was done by varying the voltage, current, and exposure time. Then, the radiography images were analysed using Contrast to Noise Ratio (CNR). From the analysis, it can be determined that the optimum exposure factors are 60 kV of voltage, 16 mA of current, and 0.125 s of exposure time which result in CNR of 5.71.

Evaluation of developmental dental anomalies in digital panoramic radiographs in Southeast Iranian Population.

PubMed

Saberi, Eshagh Ali; Ebrahimipour, Sediqe

2016-01-01

The objective of this study was to evaluate the prevalence of dental developmental anomalies in digital panoramic radiographs of the patients referred to the Zahedan medical imaging center and to evaluate the frequency of anomalies regarding the disorders in shape, position and number in the Southeast of Iran. A total of 1172 panoramic radiographs from 581 males and 586 females aged over 16 years were obtained from the files of the Zahedan medical imaging center between the years of 2014 and 2015. The selected radiographs were evaluated in terms of the anomalies such as dilacerations, taurodontism, supernumerary teeth, congenitally missing teeth, fusion, gemination, tooth impaction, tooth transposition, dens invagination, and peg lateral. Then, the anomalies were compared to each other regarding the frequency of the anomaly type (morphological, positional and numerical). Data were evaluated using descriptive statistics such as frequency and percent, and statistical tests such as X(2) at 0.05 significant level using the Statistical Package for the Social Sciences version 16.5. The prevalence of dental anomaly was 213 (18.17%), which was higher in females (9.90) than male, (8.28), however, this difference was not statistically significant (P > 0.05). The prevalence of dilacerated teeth was 62 (5.29%), taurodontism 63 (5.38%), supernumerary teeth 6 (0.51%), congenitally missing teeth 13 (1.11%), fusion 1 (0.09%), gemination 1 (0.09%), impaction 40 (3.41%), transposition 2 (0.18%), dens invagination 16 (1.37) and peg lateral was 9 (0.77%). The prevalence of morphological anomaly was 152 (71.36%), malposition 42 (19.72%) and numerous anomaly was 19 (8.92%). Dental anomalies are relatively common; although their occurrence is not symptomatic, they can lead to several clinical problems in patients. Detailed clinical and radiographic assessment and counseling during patient visits is a critical factor in assessing the patient's degree of difficulty to help the dentist for

Technique and interpretation in tree seed radiography

Treesearch

Howard B. Kriebel

1966-01-01

The study of internal seed structure by radiography requires techniques which will give good definition. To establish the best procedures, we conducted a series of experiments in which we manipulated the principal controllable variables affecting the quality of X-radiographs: namely, focus-to-film distance, film speed (grain), exposure time, kilovoltage, and...

Action research in radiography: What it is and how it can be conducted

PubMed Central

Munn, Zachary; Pearson, Alan; Jordan, Zoe; Murphy, Frederick; Pilkington, Diana

2013-01-01

Action research is a form of research that investigates and describes a social or work situation with the aim of achieving a change which results in improvement. This article emphasizes the potential for action research to be a useful research method in radiography. A search was conducted to determine the extent to which action research has been utilized in radiography. Although action research has been used in a number of health-care settings, there are no published examples of action research being utilized in a clinical medical imaging department. Action research is discussed in detail, along with an example guide for an action research study. Action research has been identified as a useful way to affect change, to involve radiographers in the research process, and to introduce evidence-based practice to radiography. PMID:26229607

Digital Radiography Using Digital Detector Arrays Fulfills Critical Applications for Offshore Pipelines

NASA Astrophysics Data System (ADS)

Moreira, EdsonVasques; Barbosa Rabello, JoséMaurício; Pereira, MarcelodosSantos; Lopes, RicardoTadeu; Zscherpel, Uwe

2010-12-01

Digital radiography in the inspection of welded pipes to be installed under deep water offshore gas and oil pipelines, like a presalt in Brazil, in the paper has been investigated. The aim is to use digital radiography for nondestructive testing of welds as it is already in use in the medical, aerospace, security, automotive, and petrochemical sectors. Among the current options, the DDA (Digital Detector Array) is considered as one of the best solutions to replace industrial films, as well as to increase the sensitivity to reduce the inspection cycle time. This paper shows the results of this new technique, comparing it to radiography with industrial films systems. In this paper, 20 test specimens of longitudinal welded pipe joints, specially prepared with artificial defects like cracks, lack of fusion, lack of penetration, and porosities and slag inclusions with varying dimensions and in 06 different base metal wall thicknesses, were tested and a comparison of the techniques was made. These experiments verified the purposed rules for parameter definitions and selections to control the required digital radiographic image quality as described in the draft international standard ISO/DIS 10893-7. This draft is first standard establishing the parameters for digital radiography on weld seam of welded steel pipes for pressure purposes to be used on gas and oil pipelines.

Problem-based learning for radiological technologists: a comparison of student attitudes toward plain radiography.

PubMed

Terashita, Takayoshi; Tamura, Naomi; Kisa, Kengo; Kawabata, Hidenobu; Ogasawara, Katsuhiko

2016-09-05

Knowledge and skill expected of healthcare providers continues to increase alongside developments in medicine and healthcare. Problem-based learning (PBL) is therefore increasingly necessary in training courses for radiological technologists. However, it is necessary to evaluate the effects of PBL to completely introduce it in our education programs. As a Hypothesis, it seems that a change occurs in the student's attitudes by participating in PBL practical training. There is the Semantic Differential (SeD) technique as a method to identify student's attitudes. We conceived that PBL could be appropriately evaluated by using SeD technique. In this paper, we evaluated PBL for plain radiography practical training using the SeD technique. Thirty-eight third-year students studying radiological technology participated. PBL was introduced to practical training in plain radiography positioning techniques. Five sessions lasting 5 h each were delivered over a 5-week period during November to December 2012. The clinical scenario was an emergency case with multiple trauma requiring plain radiography. Groups comprising approximately eight students created workflows for trauma radiography with consideration of diagnostic accuracy and patient safety. Furthermore, students groups conducted plain radiography on a patient phantom according to created workflows and were then guided by feedback from professional radiologists. All students answered SeD questionnaires to assess views on plain radiography before instruction to provide preliminary practical training reports and after completing practical training. The factors were identified using factor analysis of the questionnaires, which were answered before and after each practical training session. On evaluation of the relationships between factors and question items according to factor loading, we identified "reluctance", "confidence", and "exhaustion" as the predominant attitudes before practical training. Similarly, we identified

FliMax, a novel stimulus device for panoramic and highspeed presentation of behaviourally generated optic flow.

PubMed

Lindemann, J P; Kern, R; Michaelis, C; Meyer, P; van Hateren, J H; Egelhaaf, M

2003-03-01

A high-speed panoramic visual stimulation device is introduced which is suitable to analyse visual interneurons during stimulation with rapid image displacements as experienced by fast moving animals. The responses of an identified motion sensitive neuron in the visual system of the blowfly to behaviourally generated image sequences are very complex and hard to predict from the established input circuitry of the neuron. This finding suggests that the computational significance of visual interneurons can only be assessed if they are characterised not only by conventional stimuli as are often used for systems analysis, but also by behaviourally relevant input.

Enhancement of digital radiography image quality using a convolutional neural network.

PubMed

Sun, Yuewen; Li, Litao; Cong, Peng; Wang, Zhentao; Guo, Xiaojing

2017-01-01

Digital radiography system is widely used for noninvasive security check and medical imaging examination. However, the system has a limitation of lower image quality in spatial resolution and signal to noise ratio. In this study, we explored whether the image quality acquired by the digital radiography system can be improved with a modified convolutional neural network to generate high-resolution images with reduced noise from the original low-quality images. The experiment evaluated on a test dataset, which contains 5 X-ray images, showed that the proposed method outperformed the traditional methods (i.e., bicubic interpolation and 3D block-matching approach) as measured by peak signal to noise ratio (PSNR) about 1.3 dB while kept highly efficient processing time within one second. Experimental results demonstrated that a residual to residual (RTR) convolutional neural network remarkably improved the image quality of object structural details by increasing the image resolution and reducing image noise. Thus, this study indicated that applying this RTR convolutional neural network system was useful to improve image quality acquired by the digital radiography system.

The New Facilities for Neutron Radiography at the LVR-15 Reactor

NASA Astrophysics Data System (ADS)

Soltes, J.; Viererbl, L.; Vacik, J.; Tomandl, I.; Krejci, F.; Jakubek, J.

2016-09-01

Neutron radiography is an imaging method often used at research reactor sites. Back in 2011 a project was started with the goal to build a neutron radiography facility at the site of the LVR-15 research reactor in Rez, Czech Republic. In the scope of the project two horizontal channels were adapted for the needs of neutron radiography. This comprises the HC1 channel which offers an intense thermal neutron beam with a diameter of 10 cm, which can be used for imaging of larger samples, and the HC3 channel which beam is restricted just to 4x80 mm2, but is highly thermalized, collimated and reduced from gamma background, thus capable of providing better radiograph resolution. Both facilities are equipped with newest Timepix based detectors, with thin 6LiF converters for neutron detection capable of delivering high resolution. Both facilities offer a unique opportunity for non-destructive testing in the Czech region. In 2015 both facilities were put into test operation and several radiographs were acquired, which are presented in the following text.

Detection of gastritis by single- and double-contrast radiography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thoeni, R.F.; Goldberg, H.I.; Ominsky, S.

1983-09-01

Sixty-eight patients with various types of gastritis, 23 patients with normal stomachs, and four patients with other gastric diseases were examined in a prospective study to assess the sensitivity and specificity of single-contrast (SC) and double-contrast (DC) upper gastrointestinal examinations in the evaluation of gastritis. All patients underwent endoscopy with biopsy followed first by DC and then by SC radiography. The respective sensitivities of SC and DC radiography were 58% and 72% for all examinations and 59% and 77% for adequate examinations only. The respective specificities were 59% and 55% based on all examinations. Useful radiographic features included polypoid defectsmore » and erosions detected by both methods, abnormal folds and flattened margins detected by the SC technique, and narrowed lumen and crenulated margins detected by the DC technique. In 93% of all cases, the correct diagnosis was based on two or more of these radiographic features. According to this study, the radiographic sensitivity in the detection of gastritis is reliable only in cases of moderate-to-severe disease and only when based on findings of the DC examination. Neither SC nor DC radiography should be used as the primary screening method for patients with suspected gastritis, and the radiographic diagnosis should be restricted to the terms ''erosive'' or ''nonerosive gastritis.''« less

The phrenic nerve with accompanying vessels: a silent cause of cardiovascular border obliteration on chest radiography.

PubMed

Farhana, Shiri; Ashizawa, Kazuto; Hayashi, Hideyuki; Ogihara, Yukihiro; Aso, Nobuya; Hayashi, Kuniaki; Uetani, Masataka

2015-12-01

Our aim was to clarify the frequency of cardiovascular border obliteration on frontal chest radiography and to prove that the phrenic nerve with accompanying vessels can be considered as a cause of obliteration of cardiovascular border on an otherwise normal chest radiography. Two radiologists reviewed chest radiographs and computed tomography (CT) images of 100 individuals. CT confirmed the absence of intrapulmonary or extrapulmonary abnormalities in all of them. We examined the frequency of cardiovascular border obliteration on frontal chest radiography and summarized the causes of obliteration as pericardial fat pad, phrenic nerve, intrafissure fat, pulmonary vessels, and others, comparing them with CT in each case. Cardiovascular border was obliterated on frontal chest radiography in 46 cases on the right and in 61 on the left. The phrenic nerve with accompanying vessels was found to be a cause of obliteration in 34 of 46 cases (74%) on the right and 29 of 61 (48%) cases on the left. The phrenic nerve was the most frequent cause of cardiovascular border obliteration on both sides. The phrenic nerve with accompanying vessels, forming a prominent fold of parietal pleura, can be attributed as a cause of cardiovascular border obliteration on frontal chest radiography.

[TUBERCULOSIS SCREENING BY CHEST RADIOGRAPHY AMONG INTERNATIONAL STUDENTS AT JAPANESE LANGUAGE SCHOOLS IN OSAKA CITY].

PubMed

Tsuda, Yuko; Matsumoto, Kenji; Komukai, Jun; Furukawa, Kanae; Saito, Kazumi; Shimouchi, Akira

2015-10-01

With a broader aim of controlling pulmonary tuberculosis (TB) among foreigners, here, we have reported the findings of chest radiography screening for TB among international students at Japanese language schools in Osaka city. Between April 2011 and December 2013, 4,529 international students from 19 Japanese language schools in Osaka city underwent chest radiography for TB screening. The chest radiographs were studied in reference to the student's sex, age, nationality, and date of entry to Japan as well as any health conditions present at the time of screening. We further analyzed the bacterial information and pulmonary TB classification based on chest radiography findings of students who were identified to be positive for TB. Information on the implementation of health education was also gathered. The results revealed that 52.5% of the students who underwent chest radiography came from China, 20.3 % from South Korea, and 16.3% from Vietnam. Of the students, 52.9% were male and 47.1% were female. The median age of students was 23 years (range: 14-70 years). The median number of days from the first date of entry to Japan up until the radiography screening was 63 days. Based on the chest radiography findings, 71 students (1.6%) were suspected to have TB; however, further detailed examination confirmed that 19 students (0.4%) had active TB. This percentage is significantly higher than the 0.1% TB identification rate among residents in Osaka city of the same time period (P<0.001), which was also determined by chest radiography. The median age of the 19 TB positive patients was 23 years. Among them, 14 (73.7%) were male. The median time from the date of entry to Japan to the date of the chest radiography screening was 137 days. For 16 of those students, the entry to Japan was within 1 year of the radiography. Of the 19 TB positive patients, 16 (84.2%) did not have respiratory symptoms, 15 (79.0%) had sputum smear negative results, and 17 (89.5%) had no cavity. Health

Radiography with cosmic-ray and compact accelerator muons; Exploring inner-structure of large-scale objects and landforms

PubMed Central

NAGAMINE, Kanetada

2016-01-01

Cosmic-ray muons (CRM) arriving from the sky on the surface of the earth are now known to be used as radiography purposes to explore the inner-structure of large-scale objects and landforms, ranging in thickness from meter to kilometers scale, such as volcanic mountains, blast furnaces, nuclear reactors etc. At the same time, by using muons produced by compact accelerators (CAM), advanced radiography can be realized for objects with a thickness in the sub-millimeter to meter range, with additional exploration capability such as element identification and bio-chemical analysis. In the present report, principles, methods and specific research examples of CRM transmission radiography are summarized after which, principles, methods and perspective views of the future CAM radiography are described. PMID:27725469

Radiography with cosmic-ray and compact accelerator muons; Exploring inner-structure of large-scale objects and landforms.

PubMed

Nagamine, Kanetada

2016-01-01

Cosmic-ray muons (CRM) arriving from the sky on the surface of the earth are now known to be used as radiography purposes to explore the inner-structure of large-scale objects and landforms, ranging in thickness from meter to kilometers scale, such as volcanic mountains, blast furnaces, nuclear reactors etc. At the same time, by using muons produced by compact accelerators (CAM), advanced radiography can be realized for objects with a thickness in the sub-millimeter to meter range, with additional exploration capability such as element identification and bio-chemical analysis. In the present report, principles, methods and specific research examples of CRM transmission radiography are summarized after which, principles, methods and perspective views of the future CAM radiography are described.

Spectroscopic neutron radiography for a cargo scanning system

NASA Astrophysics Data System (ADS)

Rahon, Jill; Danagoulian, Areg; MacDonald, Thomas D.; Hartwig, Zachary S.; Lanza, Richard C.

2016-06-01

Detection of cross-border smuggling of illicit materials and contraband is a challenge that requires rapid, low-dose, and efficient radiographic technology. The work we describe here is derived from a technique which uses monoenergetic gamma rays from low energy nuclear reactions, such as 11B(d,nγ)12C, to perform radiographic analysis of shipping containers. Transmission ratios of multiple monoenergetic gamma lines resulting from several gamma producing nuclear reactions can be employed to detect materials of high atomic number (Z), the details of which will be described in a separate paper. Inherent in this particular nuclear reaction is the production of fast neutrons which could enable neutron radiography and further characterization of the effective-Z of the cargo, especially within the range of lower Z. Previous research efforts focused on the use of total neutron counts in combination with X-ray radiography to characterize the hydrogenous content of the cargo. We present a technique of performing transmitted neutron spectral analysis to reconstruct the effective Z and potentially the density of the cargo. This is made possible by the large differences in the energy dependence of neutron scattering cross-sections between hydrogenous materials and those of higher Z. These dependencies result in harder transmission spectra for hydrogenous cargoes than those of non-hydrogenous cargoes. Such observed differences can then be used to classify the cargo based on its hydrogenous content. The studies presented in this paper demonstrate that such techniques are feasible and can provide a contribution to cargo security, especially when used in concert with gamma radiography.

Comparison of three-view thoracic radiography and computed tomography for detection of pulmonary nodules in dogs with neoplasia.

PubMed

Armbrust, Laura J; Biller, David S; Bamford, Aubrey; Chun, Ruthanne; Garrett, Laura D; Sanderson, Michael W

2012-05-01

To compare the detection of pulmonary nodules by use of 3-view thoracic radiography and CT in dogs with confirmed neoplasia. Prospective case series. 33 dogs of various breeds. 3 interpreters independently evaluated 3-view thoracic radiography images. The location and size of pulmonary nodules were recorded. Computed tomographic scans of the thorax were obtained and evaluated by a single interpreter. The location, size, margin, internal architecture, and density of pulmonary nodules were recorded. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for thoracic radiography (with CT as the gold standard). 21 of 33 (64%) dogs had pulmonary nodules or masses detected on CT. Of the dogs that had positive CT findings, 17 of 21 (81%) had pulmonary nodules or masses detected on radiographs by at least 1 interpreter. Sensitivity of radiography ranged from 71% to 95%, and specificity ranged from 67% to 92%. Radiography had a positive predictive value of 83% to 94% and a negative predictive value of 65% to 89%. The 4 dogs that were negative for nodules on thoracic radiography but positive on CT were all large-breed to giant-breed dogs with osteosarcoma. CT was more sensitive than radiography for detection of pulmonary nodules. This was particularly evident in large-breed to giant-breed dogs. Thoracic CT is recommended in large-breed to giant-breed dogs with osteosarcoma if the detection of pulmonary nodules will change treatment.

Comparison of scatter rejection and low-contrast performance of scan equalization digital radiography (SEDR), slot-scan digital radiography, and full-field digital radiography systems for chest phantom imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu Xinming; Shaw, Chris C.; Lai, Chao-Jen

Purpose: To investigate and compare the scatter rejection properties and low-contrast performance of the scan equalization digital radiography (SEDR) technique to the slot-scan and conventional full-field digital radiography techniques for chest imaging. Methods: A prototype SEDR system was designed and constructed with an a-Se flat-panel (FP) detector to improve image quality in heavily attenuating regions of an anthropomorphic chest phantom. Slot-scanning geometry was used to reject scattered radiation without attenuating primary x rays. The readout scheme of the FP was modified to erase accumulated scatter signals prior to image readout. A 24-segment beam width modulator was developed to regulate x-raymore » exposures regionally and compensate for the low x-ray flux in heavily attenuating regions. To measure the scatter-to-primary ratios (SPRs), a 2 mm thick lead plate with a 2-D array of aperture holes was used to measure the primary signals, which were then subtracted from those obtained without the lead plate to determine scatter components. A 2-D array of aluminum beads (3 mm in diameter) was used as the low-contrast objects to measure the contrast ratios (CRs) and contrast-to-noise ratios (CNRs) for evaluating the low-contrast performance in chest phantom images. A set of two images acquired with the same techniques were subtracted from each other to measure the noise levels. SPRs, CRs, and CNRs of the SEDR images were measured in four anatomical regions of chest phantom images and compared to those of slot-scan images and full-field images acquired with and without antiscatter grid. Results: The percentage reduction of SPR (percentage of SPRs reduced with scatter removal/rejection methods relative to that for nongrid full-field imaging) averaged over four anatomical regions was measured to be 80%, 83%, and 71% for SEDR, slot-scan, and full-field with grid, respectively. The average CR over four regions was found to improve over that for nongrid full

Mobile radiography at a music festival.

PubMed

Walker, A; Brenchley, J; Hughes, N

2009-08-01

Limb injuries are common at music festival sites and traditionally patients seen by on-site medical services require referral to hospital emergency departments for radiographic exclusion of bony injury. This takes clinical personnel off site, increases demand on local emergency departments and is inconvenient for revellers. This is an audit of the use of a portable digital radiography system at the Virgin music festival in Staffordshire over a 3-year period.

Neurosensoric disturbances after surgical removal of the mandibular third molar based on either panoramic imaging or cone beam CT scanning: A randomized controlled trial (RCT).

PubMed

Petersen, Lars B; Vaeth, Michael; Wenzel, Ann

2016-01-01

Pre-surgical CBCT has been suggested before removal of the mandibular third molar. Currently, the standard-of-care is two-dimensional (2D) panoramic imaging. The aim of this randomized controlled trial was to analyse possible differences in neurosensoric disturbances of the inferior alveolar nerve between patients undergoing either panoramic imaging or CBCT before surgical removal of the mandibular third molar. Furthermore, the aim was to perform a sensitivity analysis to assess the statistical significance of different assumptions related to sample size calculations. 230 patients were randomized to a scan group and a non-scan group. All patients were referred from practicing dentists in the Copenhagen area. Inclusion criteria were overlap of the root complex and the mandibular canal on a 2D radiographic image. Central allocation of the randomization code and double blind settings were established. The surgical removal was performed in a specialized surgical practice geographically and personally separated from the study practice. Registration of neurosensoric anomalies was performed with a Semmes-Weinstein test and a visual analogue scale questionnaire pre- and post-surgically. In the scan group (n = 114), 21 episodes of neurosensoric disturbances were registered and in the non-scan group (n = 116), 13 episodes of neurosensoric disturbances were registered. There was no statistically significant difference between the two groups (p = 0.14). Performing a sensitivity analysis confirmed that CBCT was not superior to panoramic imaging in avoiding neurosensoric disturbances. The use of CBCT before removal of the mandibular third molar does not seem to reduce the number of neurosensoric disturbances.

Radiological age estimation: based on third molar mineralization and eruption in Turkish children and young adults.

PubMed

Karadayi, Beytullah; Kaya, Ahsen; Kolusayın, Melek Ozlem; Karadayi, Sükriye; Afsin, Hüseyin; Ozaslan, Abdi

2012-11-01

Radiographic evaluation of mineralization and eruption stages of third molars using dental panoramic radiographies can be an efficient tool for chronological age estimation in both forensic sciences and legal medicine. The third molar tooth is utilized for dental age estimation about the age span of 15-23 years because it represents the only tooth still in development. The aim of this study is to obtain and analyze data regarding third molar development and eruption in Turkish population for dental age estimation. A total of 744 dental panoramic radiographies of 394 female and 350 male subjects aged between 8 and 22 years were examined. Third molar development was determined according to the Nolla classification system, and eruption was assessed relative to the alveolar bone level. Mandibular and maxillary third molars were generally found at similar stages of development on both sides. Nolla stage 6 (completed crown calcification) was reached at around the age of 15 in both maxillary and mandibular third molars in both sexes. Alveolar emergence was at around the age of 16 in males and around age of 17 in females. Although third molars' eruption shows greater variability than development of third molars, data which were obtained from this study about eruption of these teeth can be supportive to development data for age estimation.

Chest radiography practice in critically ill patients: a postal survey in the Netherlands

PubMed Central

Graat, Marleen E; Hendrikse, Karin A; Spronk, Peter E; Korevaar, Johanna C; Stoker, Jaap; Schultz, Marcus J

2006-01-01

Background To ascertain current chest radiography practice in intensive care units (ICUs) in the Netherlands. Methods Postal survey: a questionnaire was sent to all ICUs with > 5 beds suitable for mechanical ventilation; pediatric ICUs were excluded. When an ICU performed daily-routine chest radiographs in any group of patients it was considered to be a "daily-routine chest radiography" ICU. Results From the number of ICUs responding, 63% practice a daily-routine strategy, in which chest radiographs are obtained on a daily basis without any specific reason. A daily-routine chest radiography strategy is practiced less frequently in university-affiliated ICUs (50%) as compared to other ICUs (68%), as well as in larger ICUs (> 20 beds, 50%) as compared to smaller ICUs (< 20 beds, 65%) (P > 0.05). Remarkably, physicians that practice a daily-routine strategy consider daily-routine radiographs helpful in guiding daily practice in less than 30% of all performed radiographs. Chest radiographs are considered essential for verification of the position of invasive devices (81%) and for diagnosing pneumothorax, pneumonia or acute respiratory distress syndrome (82%, 74% and 69%, respectively). On demand chest radiographs are obtained after introduction of thoracic drains, central venous lines and endotracheal tubes in 98%, 84% and 75% of responding ICUs, respectively. Chest films are also obtained in case of ventilatory deterioration (49% of responding ICUs), and after cardiopulmonary resuscitation (59%), tracheotomy (58%) and mini-tracheotomy (23%). Conclusion There is notable lack of consensus on chest radiography practice in the Netherlands. This survey suggests that a large number of intensivists may doubt the value of daily-routine chest radiography, but still practice a daily-routine strategy. PMID:16848892

The evaluation the magnitude radiation exposure dose rate in digital radiography room design

NASA Astrophysics Data System (ADS)

Dwiyanto, Agung; Setia Budi, Wahyu; Hardiman, Gagoek

2017-12-01

This study discusses the dose rate in digital radiography room, buit according to meet the provisions of KEMENKES No.1014 / Menkes / SK / XI / 2008 and Regulation of BAPETEN No. 8 / 2011. The provisions primary concern of radiation safety, not comfort, by considering the space design. There are five aspects to consider in designing the space: functionality, comfort, security, movement activities and aesthetics. However provisions only met three aspects of the design, which are a function, security and movement activity. Therefore, it is necessary to evaluate digital radiography room in terms of its ability to control external radiation exposure to be safe and comfortable The dose rate is measured by the range of primary and secondary radiation in the observation points by using Surveymeter. All data are obtained by the preliminary survey prior to the study. Furthermore, the review of digital radiography room is done based on architectural design theory. The dose rate for recommended improvement room is recalculated using the same method as the actual room with the help of computer modeling. The result of dose rate calculation at the inner and outer part of digital radiography observation room shows that in-room dose for a week at each measuring point exceeds the allowable dose limit both for staff and public. During a week of observation, the outdoor dose at some measuring points exceeds the dose limit set by the KEMENKES No.1014 / Menkes / SK / XI / 2008 and Regulation BEPETEN No 8/2011. Meanwhile, the result of dose rate calculation in the inner and outer part of the improved digital radiography room can meet the applicable regulations better.

X-ray backscatter imaging for radiography by selective detection and snapshot: Evolution, development, and optimization

NASA Astrophysics Data System (ADS)

Shedlock, Daniel

Compton backscatter imaging (CBI) is a single-sided imaging technique that uses the penetrating power of radiation and unique interaction properties of radiation with matter to image subsurface features. CBI has a variety of applications that include non-destructive interrogation, medical imaging, security and military applications. Radiography by selective detection (RSD), lateral migration radiography (LMR) and shadow aperture backscatter radiography (SABR) are different CBI techniques that are being optimized and developed. Radiography by selective detection (RSD) is a pencil beam Compton backscatter imaging technique that falls between highly collimated and uncollimated techniques. Radiography by selective detection uses a combination of single- and multiple-scatter photons from a projected area below a collimation plane to generate an image. As a result, the image has a combination of first- and multiple-scatter components. RSD techniques offer greater subsurface resolution than uncollimated techniques, at speeds at least an order of magnitude faster than highly collimated techniques. RSD scanning systems have evolved from a prototype into near market-ready scanning devices for use in a variety of single-sided imaging applications. The design has changed to incorporate state-of-the-art detectors and electronics optimized for backscatter imaging with an emphasis on versatility, efficiency and speed. The RSD system has become more stable, about 4 times faster, and 60% lighter while maintaining or improving image quality and contrast over the past 3 years. A new snapshot backscatter radiography (SBR) CBI technique, shadow aperture backscatter radiography (SABR), has been developed from concept and proof-of-principle to a functional laboratory prototype. SABR radiography uses digital detection media and shaded aperture configurations to generate near-surface Compton backscatter images without scanning, similar to how transmission radiographs are taken. Finally, a

42 CFR 37.42 - Chest radiograph specifications-digital radiography systems.

Code of Federal Regulations, 2014 CFR

2014-10-01

... resolution, modulation transfer function (MTF), image signal-to-noise and detective quantum efficiency must... Information Object Definitions, sections: Computed Radiography Image Information Object Definition; Digital X...

Investigation of time-resolved proton radiography using x-ray flat-panel imaging system

NASA Astrophysics Data System (ADS)

Jee, K.-W.; Zhang, R.; Bentefour, E. H.; Doolan, P. J.; Cascio, E.; Sharp, G.; Flanz, J.; Lu, H.-M.

2017-03-01

Proton beam therapy benefits from the Bragg peak and delivers highly conformal dose distributions. However, the location of the end-of-range is subject to uncertainties related to the accuracy of the relative proton stopping power estimates and thereby the water-equivalent path length (WEPL) along the beam. To remedy the range uncertainty, an in vivo measurement of the WEPL through the patient, i.e. a proton-range radiograph, is highly desirable. Towards that goal, we have explored a novel method of proton radiography based on the time-resolved dose measured by a flat panel imager (FPI). A 226 MeV pencil beam and a custom-designed range modulator wheel (MW) were used to create a time-varying broad beam. The proton imaging technique used exploits this time dependency by looking at the dose rate at the imager as a function of time. This dose rate function (DRF) has a unique time-varying dose pattern at each depth of penetration. A relatively slow rotation of the MW (0.2 revolutions per second) and a fast image acquisition (30 frames per second, ~33 ms sampling) provided a sufficient temporal resolution for each DRF. Along with the high output of the CsI:Tl scintillator, imaging with pixel binning (2  ×  2) generated high signal-to-noise data at a very low radiation dose (~0.1 cGy). Proton radiographs of a head phantom and a Gammex CT calibration phantom were taken with various configurations. The results of the phantom measurements show that the FPI can generate low noise and high spatial resolution proton radiographs. The WEPL values of the CT tissue surrogate inserts show that the measured relative stopping powers are accurate to ~2%. The panel did not show any noticeable radiation damage after the accumulative dose of approximately 3831 cGy. In summary, we have successfully demonstrated a highly practical method of generating proton radiography using an x-ray flat panel imager.

Investigation of time-resolved proton radiography using x-ray flat-panel imaging system.

PubMed

Jee, K-W; Zhang, R; Bentefour, E H; Doolan, P J; Cascio, E; Sharp, G; Flanz, J; Lu, H-M

2017-03-07

Proton beam therapy benefits from the Bragg peak and delivers highly conformal dose distributions. However, the location of the end-of-range is subject to uncertainties related to the accuracy of the relative proton stopping power estimates and thereby the water-equivalent path length (WEPL) along the beam. To remedy the range uncertainty, an in vivo measurement of the WEPL through the patient, i.e. a proton-range radiograph, is highly desirable. Towards that goal, we have explored a novel method of proton radiography based on the time-resolved dose measured by a flat panel imager (FPI). A 226 MeV pencil beam and a custom-designed range modulator wheel (MW) were used to create a time-varying broad beam. The proton imaging technique used exploits this time dependency by looking at the dose rate at the imager as a function of time. This dose rate function (DRF) has a unique time-varying dose pattern at each depth of penetration. A relatively slow rotation of the MW (0.2 revolutions per second) and a fast image acquisition (30 frames per second, ~33 ms sampling) provided a sufficient temporal resolution for each DRF. Along with the high output of the CsI:Tl scintillator, imaging with pixel binning (2  ×  2) generated high signal-to-noise data at a very low radiation dose (~0.1 cGy). Proton radiographs of a head phantom and a Gammex CT calibration phantom were taken with various configurations. The results of the phantom measurements show that the FPI can generate low noise and high spatial resolution proton radiographs. The WEPL values of the CT tissue surrogate inserts show that the measured relative stopping powers are accurate to ~2%. The panel did not show any noticeable radiation damage after the accumulative dose of approximately 3831 cGy. In summary, we have successfully demonstrated a highly practical method of generating proton radiography using an x-ray flat panel imager.

Comparing posteroanterior with lateral and anteroposterior chest radiography in the initial detection of parapneumonic effusions.

PubMed

Moffett, Bryan K; Panchabhai, Tanmay S; Nakamatsu, Raul; Arnold, Forest W; Peyrani, Paula; Wiemken, Timothy; Guardiola, Juan; Ramirez, Julio A

2016-12-01

It is unclear whether anteroposterior (AP) or posteroanterior with lateral (PA/Lat) chest radiographs are superior in the early detection of clinically relevant parapneumonic effusions (CR-PPEs). The objective of this study was to identify which technique is preferred for detection of PPEs using chest computed tomography (CCT) as a reference standard. A secondary analysis of a pneumonia database was conducted to identify patients who received a CCT within 24 hours of presentation and also received AP or PA/Lat chest radiographs within 24 hours of CCT. Sensitivity and specificity were then calculated by comparing the radiographic diagnosis of PPEs of both types of radiographs compared with CCT by using the existing attending radiologist interpretation. Clinical relevance of effusions was determined by CCT effusion measurement of >2.5 cm or presence of loculation. There was a statistically significant difference between the sensitivity of AP (67.3%) and PA/Lat (83.9%) chest radiography for the initial detection of CR-PPE. Of 16 CR-PPEs initially missed by AP radiography, 7 either required drainage initially or developed empyema within 30 days, whereas no complicated PPE or empyema was found in those missed by PA/Lat radiography. PA/Lat chest radiography should be the initial imaging of choice in pneumonia patients for detection of PPEs because it appears to be statistically superior to AP chest radiography. Published by Elsevier Inc.

The sensitivity of radiography of the postoperative stomach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ott, D.J.; Munitz, H.A.; Gelfand, D.W.

1982-09-01

The results of radiology and endoscopy were compared in 140 patients who had undergone gastric surgery for ulcer disease. Of 74 patients who were examined with single-contrast radiography, 37 had abnormalities that were demonstrated endoscopically. The radiographic sensitivities in these patients were: gastritis 2/22 (9%); ulcer 3/5 (60%); obstruction 8/8 (100%); and miscellaneous abnormalities 2/2 (100%). The predictive accuracy of a diagnois of ulcer was 38%. Of the 66 patients who were examined with double-contrast radiography, 33 abnormalities were found with endoscopy. The radiographic sensitivities were: gastritis 3/13 (23%); ulcer 7/10 (70%); obstruction 4/4 (100%); and miscellaneous abnormalities 6/6 (100%).more » The predictive accuracy of a diagnosis of ulcer was 44%. Radiology appears to be unreliable in diagnosing gastritis and recurrent ulceration in the post-operation stomach. The double-contrast technique does not offer significant improvement over the single-contrast method in evaluating these postoperative problems.« less

Continuous measurements of mandibular cortical width on dental panoramic radiographs for computer-aided diagnosis of osteoporosis

NASA Astrophysics Data System (ADS)

Kavitha, M. S.; Asano, Akira; Taguchi, Akira

2011-03-01

The aim of this study is to develop a computer-aided osteoporosis diagnosis system that automatically determines the inferior cortical width of the mandible continuously on dental panoramic radiographs to realize statistically more robust measurements than the conventional one-point measurements. The cortical width was continuously measured on dental panoramic radiographs by enhancing the original image, determining cortical boundaries, and finally evaluating the distance between boundaries continuously throughout the region of interest. The diagnostic performance using the average width calculated from the continuous measurement was compared with BMD at lumbar spine and femoral neck in 100 postmenopausal women of whom 50 to the development of the tool and 50 to its validation with no history of osteoporosis was evaluated. We experimentally showed the superiority of our method with improved sensitivity and specificity of identifying the development subjects were 90.0% and 75.0% in women with low spinal BMD and 81.8% and 69.2% in those with low femoral BMD, respectively. The corresponding values in the validation subjects were 93.3% and 82.9% at the lumbar spine and 92.3% and 75.7% at the femoral neck, respectively in terms of efficacy for diagnosing osteoporosis. We also assessed the diagnosis and classification of women with osteoporosis using support vector machine employing the average and variance of the continuous measurements gave excellent discrimination ability. It yields sensitivity and specificity of 90.9% and 83.8%, respectively with lumbar spine and 90.0% and 69.1%, respectively with femoral neck BMD. Performance comparison and simplicity of this method indicate that our computeraided system is readily applicable to clinical practice.

Dust deposition and removal at the MER landing sites from observations of the Panoramic Camera (Pancam) calibration targets

NASA Astrophysics Data System (ADS)

Kinch, K. M.; Bell, J. F.; Madsen, M. B.

2012-12-01

The Panoramic Cameras (Pancams) [1] on NASA's Mars Exploration Rovers have each returned in excess of 17000 images of their external calibration targets (caltargets), a set of optically well-characterized patches of materials with differing reflectance properties. During the mission dust deposition on the caltargets changed their optical reflectance properties [2]. The thickness of dust on the caltargets can be derived with high confidence from the contrast between brighter and darker colored patches. The dustier the caltarget the less contrast. We present a new history of dust deposition and removal at the two MER landing sites. Our data reveals two quite distinct dust environments. At the Spirit landing site half the Martian year is dominated by dust deposition, the other half by dust removal that usually happens during brief sharp wind events. At the Opportunity landing site the Martian year has a four-season cycle of deposition-removal-deposition-removal with dust removal happening gradually throughout the two removal seasons. Comparison to atmospheric optical depth measurements [3] shows that dust removals happen during dusty high-wind periods and that dust deposition rates are roughly proportional to the atmospheric dust load. We compare with dust deposition studies from other Mars landers and also present some early results from observation of dust on a similar camera calibration target on the Mars Science Laboratory mission. References: 1. Bell, J.F., III, et al., Mars Exploration Rover Athena Panoramic Camera (Pancam) investigation. J. Geophys. Res., 2003. 108(E12): p. 8063. 2. Kinch, K.M., et al., Dust Deposition on the Mars Exploration Rover Panoramic Camera (Pancam) Calibration Targets. J. Geophys. Res., 2007. 112(E06S03): p. doi:10.1029/2006JE002807. 3. Lemmon, M., et al., Atmospheric Imaging Results from the Mars Exploration Rovers: Spirit and Opportunity. Science, 2004. 306: p. 1753-1756. Deposited dust optical depth on the Pancam caltargets as a

Comparison of the accuracy of radiography and ultrasonography for detection of articular lesions in horses.

PubMed

Hinz, Antje; Fischer, Andrew T

2011-10-01

To compare the accuracy of ultrasonographic and radiographic examination for evaluation of articular lesions in horses. Cross-sectional study. Horses (n = 137) with articular lesions. Radiographic and ultrasonographic examinations of the affected joint(s) were performed before diagnostic or therapeutic arthroscopic surgery. Findings were recorded and compared to lesions identified during arthroscopy. In 254 joints, 432 lesions were identified by arthroscopy. The overall accuracy was 82.9% for ultrasonography and 62.2% for radiography (P < .0001) with a sensitivity of 91.4% for ultrasonography and 66.7% for radiography (P < .0001). The difference in specificity was not statistically significant (P = .2628). The negative predictive value for ultrasonography was 31.5% and 13.2% for radiography (P = .0022), the difference for the positive predictive value was not statistically significant (P = .3898). The accuracy for ultrasonography and radiography for left versus right joints was equal and corresponded with the overall results. Ultrasonographic evaluation of articular lesions was more accurate than radiographic evaluation. © Copyright 2011 by The American College of Veterinary Surgeons.

Mental Rotation, Pictured Rotation, and Tandem Rotation in Depth

DTIC Science & Technology

1997-01-01

field. Such an explanation by natural geometry conflates visual comparison with physical measurement. This application of geometry is called natural in...the theory of vision parasitic on geometry: it is unclear what could be meant by a ’mental operation of rotation’, except by reference to physical ...operation, a mental analogue of the physical operation of rotation in space. Since then the story of mental rotation has become far more complicated

A panoramic view of the Space Station Processing Facility with Unity connecting module

NASA Technical Reports Server (NTRS)

1998-01-01

In this panoramic view of the Space Station Processing Facility (SSPF) can be seen (left to right) Unity connecting module, the Rack Insertion Device and the first Multi-Purpose Launch Module, the Leonardo. Windows at the right above Leonardo allow visitors on tour to watch the activities in the SSPF. The Unity, scheduled to be launched on STS-88 in December 1998, will be mated to the Russian-built Zarya control module which will already be in orbit. STS-88 will be the first Space Shuttle launch for the International Space Station. The Italian-built MPLM, scheduled to be launched on STS-100 on Dec. 2, 1999, will be carried in the payload bay of the Shuttle orbiter, and will provide storage and additional work space for up to two astronauts when docked to the International Space Station.

Evaluation of exposure parameters in plain radiography: a comparative study with European guidelines.

PubMed

Lança, L; Silva, A; Alves, E; Serranheira, F; Correia, M

2008-01-01

Typical distribution of exposure parameters in plain radiography is unknown in Portugal. This study aims to identify exposure parameters that are being used in plain radiography in the Lisbon area and to compare the collected data with European references [Commission of European Communities (CEC) guidelines]. The results show that in four examinations (skull, chest, lumbar spine and pelvis), there is a strong tendency of using exposure times above the European recommendation. The X-ray tube potential values (in kV) are below the recommended values from CEC guidelines. This study shows that at a local level (Lisbon region), radiographic practice does not comply with CEC guidelines concerning exposure techniques. Further national/local studies are recommended with the objective to improve exposure optimisation and technical procedures in plain radiography. This study also suggests the need to establish national/local diagnostic reference levels and to proceed to effective measurements for exposure optimisation.

The “dirty chest”—correlations between chest radiography, multislice CT and tobacco burden

PubMed Central

Kirchner, J; Goltz, J P; Lorenz, F; Obermann, A; Kirchner, E M; Kickuth, R

2012-01-01

Objectives Cigarette smoking-induced airway disease commonly results in an overall increase of non-specific lung markings on chest radiography. This has been described as “dirty chest”. As the morphological substrate of this condition is similar to the anthracosilicosis of coal workers, we hypothesised that it is possible to quantify the radiological changes using the International Labour Organization (ILO) classification of pneumoconiosis. The aims of this study were to evaluate whether there is a correlation between the extent of cigarette smoking and increased lung markings on chest radiography and to correlate the chest radiographic scores with findings on CT studies. Methods In a prospective analysis a cohort of 85 smokers was examined. The cigarette consumption was evaluated in pack years (defined as 20 cigarettes per day over 1 year). Film reading was performed by two board-certified radiologists. Chest radiographs were evaluated for the presence of thickening of bronchial walls, the presence of linear or nodular opacities, and emphysema. To correlate the smoking habits with the increase of overall lung markings in chest radiography, the ILO profusion score was converted to numbers ranging from zero to nine. Chest radiographs were rated according to the complete set of standard films of the revised ILO classification. Results 63/85 (74%) of the smokers showed an increase in overall lung markings on chest radiography; 32 (37%) had an ILO profusion score of <1/1, 29 (34%) had an ILO profusion score of <2/2 and 2 (2%) had an ILO score of ≥2/2. There was a significant positive linear correlation between the increase of overall lung markings on chest radiography and the cigarette consumption quantified as pack years (r=0.68). The majority of the heavy smokers (>40 pack years) showed emphysema; there was no significant difference between the prevalence of emphysema as diagnosed by CT (62%) or chest radiography (71%) (p<0.05).The most common findings in CT

Neutron Radiography of Fluid Flow for Geothermal Energy Research

NASA Astrophysics Data System (ADS)

Bingham, P.; Polsky, Y.; Anovitz, L.; Carmichael, J.; Bilheux, H.; Jacobsen, D.; Hussey, D.

Enhanced geothermal systems seek to expand the potential for geothermal energy by engineering heat exchange systems within the earth. A neutron radiography imaging method has been developed for the study of fluid flow through rock under environmental conditions found in enhanced geothermal energy systems. For this method, a pressure vessel suitable for neutron radiography was designed and fabricated, modifications to imaging instrument setups were tested, multiple contrast agents were tested, and algorithms developed for tracking of flow. The method has shown success for tracking of single phase flow through a manufactured crack in a 3.81 cm (1.5 inch) diameter core within a pressure vessel capable of confinement up to 69 MPa (10,000 psi) using a particle tracking approach with bubbles of fluorocarbon-based fluid as the ;particles; and imaging with 10 ms exposures.

Relationship Between the Number of Clinical Sites in Radiography Programs and Job Placement Rates of Graduates.

PubMed

Harrell, Angela; Matthews, Eric

2016-07-01

To determine whether a relationship exists between the number of clinical sites available in radiography programs accredited by the Joint Review Committee on Education in Radiologic Technology and the job placement rates of graduates. We performed a secondary analysis of data on job placement rates and the number of clinical sites available in 438 degree-granting radiography programs from January 2015 to March 2015. A weak, negative, nonsignificant correlation existed between the number of clinical sites and the job placement rate (Spearman's rho = -.113, n = 438, P = .018). The coefficient of determination was 1.28%.Discussion Research evaluating factors contributing to graduate employability is limited but indicates no need for radiography program administrators to adjust clinical site numbers solely on the basis of improving graduate employability. The number of clinical sites available in a radiography program is not related to the job placement rate of its graduates. ©2016 American Society of Radiologic Technologists.

200 MeV Proton Radiography Studies with a Hand Phantom Using a Prototype Proton CT Scanner

PubMed Central

Plautz, Tia; Bashkirov, V.; Feng, V.; Hurley, F.; Johnson, R.P.; Leary, C.; Macafee, S.; Plumb, A.; Rykalin, V.; Sadrozinski, H.F.-W.; Schubert, K.; Schulte, R.; Schultze, B.; Steinberg, D.; Witt, M.; Zatserklyaniy, A.

2014-01-01

Proton radiography has applications in patient alignment and verification procedures for proton beam radiation therapy. In this paper, we report an experiment which used 200 MeV protons to generate proton energy-loss and scattering radiographs of a hand phantom. The experiment used the first-generation proton CT scanner prototype, which was installed on the research beam line of the clinical proton synchrotron at Loma Linda University Medical Center (LLUMC). It was found that while both radiographs displayed anatomical details of the hand phantom, the energy-loss radiograph had a noticeably higher resolution. Nonetheless, scattering radiography may yield more contrast between soft and bone tissue than energy-loss radiography, however, this requires further study. This study contributes to the optimization of the performance of the next-generation of clinical proton CT scanners. Furthermore, it demonstrates the potential of proton imaging (proton radiography and CT), which is now within reach of becoming available as a new, potentially low-dose medical imaging modality. PMID:24710156

Rotator cuff tendon connections with the rotator cable.

PubMed

Rahu, Madis; Kolts, Ivo; Põldoja, Elle; Kask, Kristo

2017-07-01

The literature currently contains no descriptions of the rotator cuff tendons, which also describes in relation to the presence and characteristics of the rotator cable (anatomically known as the ligamentum semicirculare humeri). The aim of the current study was to elucidate the detailed anatomy of the rotator cuff tendons in association with the rotator cable. Anatomic dissection was performed on 21 fresh-frozen shoulder specimens with an average age of 68 years. The rotator cuff tendons were dissected from each other and from the glenohumeral joint capsule, and the superior glenohumeral, coracohumeral, coracoglenoidal and semicircular (rotator cable) ligaments were dissected. Dissection was performed layer by layer and from the bursal side to the joint. All ligaments and tendons were dissected in fine detail. The rotator cable was found in all specimens. It was tightly connected to the supraspinatus (SSP) tendon, which was partly covered by the infraspinatus (ISP) tendon. The posterior insertion area of the rotator cable was located in the region between the middle and inferior facets of the greater tubercle of the humerus insertion areas for the teres minor (TM), and ISP tendons were also present and fibres from the SSP extended through the rotator cable to those areas. The connection between the rotator cable and rotator cuff tendons is tight and confirms the suspension bridge theory for rotator cuff tears in most areas between the SSP tendons and rotator cable. In its posterior insertion area, the rotator cable is a connecting structure between the TM, ISP and SSP tendons. These findings might explain why some patients with relatively large rotator cuff tears can maintain seamless shoulder function.

X-ray absorption radiography for high pressure shock wave studies

NASA Astrophysics Data System (ADS)

Antonelli, L.; Atzeni, S.; Batani, D.; Baton, S. D.; Brambrink, E.; Forestier-Colleoni, P.; Koenig, M.; Le Bel, E.; Maheut, Y.; Nguyen-Bui, T.; Richetta, M.; Rousseaux, C.; Ribeyre, X.; Schiavi, A.; Trela, J.

2018-01-01

The study of laser compressed matter, both warm dense matter (WDM) and hot dense matter (HDM), is relevant to several research areas, including materials science, astrophysics, inertial confinement fusion. X-ray absorption radiography is a unique tool to diagnose compressed WDM and HDM. The application of radiography to shock-wave studies is presented and discussed. In addition to the standard Abel inversion to recover a density map from a transmission map, a procedure has been developed to generate synthetic radiographs using density maps produced by the hydrodynamics code DUED. This procedure takes into account both source-target geometry and source size (which plays a non negligible role in the interpretation of the data), and allows to reproduce transmission data with a good degree of accuracy.

Automatic exposure for panoramic systems in uncontrolled lighting conditions: a football stadium case study

NASA Astrophysics Data System (ADS)

Gaddam, Vamsidhar Reddy; Griwodz, Carsten; Halvorsen, Pâl.

2014-02-01

One of the most common ways of capturing wide eld-of-view scenes is by recording panoramic videos. Using an array of cameras with limited overlapping in the corresponding images, one can generate good panorama images. Using the panorama, several immersive display options can be explored. There is a two fold synchronization problem associated to such a system. One is the temporal synchronization, but this challenge can easily be handled by using a common triggering solution to control the shutters of the cameras. The other synchronization challenge is the automatic exposure synchronization which does not have a straight forward solution, especially in a wide area scenario where the light conditions are uncontrolled like in the case of an open, outdoor football stadium. In this paper, we present the challenges and approaches for creating a completely automatic real-time panoramic capture system with a particular focus on the camera settings. One of the main challenges in building such a system is that there is not one common area of the pitch that is visible to all the cameras that can be used for metering the light in order to nd appropriate camera parameters. One approach we tested is to use the green color of the eld grass. Such an approach provided us with acceptable results only in limited light conditions.A second approach was devised where the overlapping areas between adjacent cameras are exploited, thus creating pairs of perfectly matched video streams. However, there still existed some disparity between di erent pairs. We nally developed an approach where the time between two temporal frames is exploited to communicate the exposures among the cameras where we achieve a perfectly synchronized array. An analysis of the system and some experimental results are presented in this paper. In summary, a pilot-camera approach running in auto-exposure mode and then distributing the used exposure values to the other cameras seems to give best visual results.

Dose measurements for dental cone-beam CT: a comparison with MSCT and panoramic imaging

NASA Astrophysics Data System (ADS)

Deman, P.; Atwal, P.; Duzenli, C.; Thakur, Y.; Ford, N. L.

2014-06-01

To date there is a lack of published information on appropriate methods to determine patient doses from dental cone-beam computed tomography (CBCT) equipment. The goal of this study is to apply and extend the methods recommended in the American Association of Physicists in Medicine (AAPM) Report 111 for CBCT equipment to characterize dose and effective dose for a range of dental imaging equipment. A protocol derived from the one proposed by Dixon et al (2010 Technical Report 111, American Association of Physicist in Medicine, MD, USA), was applied to dose measurements of multi-slice CT, dental CBCT (small and large fields of view (FOV)) and a dental panoramic system. The computed tomography dose index protocol was also performed on the MSCT to compare both methods. The dose distributions in a cylindrical polymethyl methacrylate phantom were characterized using a thimble ionization chamber and Gafchromic™ film (beam profiles). Gafchromic™ films were used to measure the dose distribution in an anthropomorphic phantom. A method was proposed to extend dose estimates to planes superior and inferior to the central plane. The dose normalized to 100 mAs measured in the center of the phantom for the large FOV dental CBCT (11.4 mGy/100 mAs) is two times lower than that of MSCT (20.7 mGy/100 mAs) for the same FOV, but approximately 15 times higher than for a panoramic system (0.6 mGy/100 mAs). The effective dose per scan (in clinical conditions) found for the dental CBCT are 167.60 ± 3.62, 61.30 ± 3.88 and 92.86 ± 7.76 mSv for the Kodak 9000 (fixed scan length of 3.7 cm), and the iCAT Next Generation for 6 cm and 13 cm scan lengths respectively. The method to extend the dose estimates from the central slice to superior and inferior slices indicates a good agreement between theory and measurement. The Gafchromic™ films provided useful beam profile data and 2D distributions of dose in phantom.

Neurosensoric disturbances after surgical removal of the mandibular third molar based on either panoramic imaging or cone beam CT scanning: A randomized controlled trial (RCT)

PubMed Central

Vaeth, Michael; Wenzel, Ann

2016-01-01

Objective: Pre-surgical CBCT has been suggested before removal of the mandibular third molar. Currently, the standard-of-care is two-dimensional (2D) panoramic imaging. The aim of this randomized controlled trial was to analyse possible differences in neurosensoric disturbances of the inferior alveolar nerve between patients undergoing either panoramic imaging or CBCT before surgical removal of the mandibular third molar. Furthermore, the aim was to perform a sensitivity analysis to assess the statistical significance of different assumptions related to sample size calculations. Methods: 230 patients were randomized to a scan group and a non-scan group. All patients were referred from practicing dentists in the Copenhagen area. Inclusion criteria were overlap of the root complex and the mandibular canal on a 2D radiographic image. Central allocation of the randomization code and double blind settings were established. The surgical removal was performed in a specialized surgical practice geographically and personally separated from the study practice. Registration of neurosensoric anomalies was performed with a Semmes–Weinstein test and a visual analogue scale questionnaire pre- and post-surgically. Results: In the scan group (n = 114), 21 episodes of neurosensoric disturbances were registered and in the non-scan group (n = 116), 13 episodes of neurosensoric disturbances were registered. There was no statistically significant difference between the two groups (p = 0.14). Performing a sensitivity analysis confirmed that CBCT was not superior to panoramic imaging in avoiding neurosensoric disturbances. Conclusions: The use of CBCT before removal of the mandibular third molar does not seem to reduce the number of neurosensoric disturbances. PMID:26648386

Time resolved analysis of water drainage in porous asphalt concrete using neutron radiography.

PubMed

Poulikakos, L D; Sedighi Gilani, M; Derome, D; Jerjen, I; Vontobel, P

2013-07-01

Porous asphalt as a road surface layer controls aquaplaning as rain water can drain through its highly porous structure. The process of water drainage through this permeable layer is studied using neutron radiography. Time-resolved water configuration and distribution within the porous structure are reported. It is shown that radiography depicts the process of liquid water transport within the complex geometry of porous asphalt, capturing water films, filled dead end pores and water islands. Copyright © 2013 Elsevier Ltd. All rights reserved.

Development of an interpretive simulation tool for the proton radiography technique

DOE Office of Scientific and Technical Information (OSTI.GOV)

Levy, M. C., E-mail: levymc@stanford.edu; Lawrence Livermore National Laboratory, Livermore, California 94551; Ryutov, D. D.

2015-03-15

Proton radiography is a useful diagnostic of high energy density (HED) plasmas under active theoretical and experimental development. In this paper, we describe a new simulation tool that interacts realistic laser-driven point-like proton sources with three dimensional electromagnetic fields of arbitrary strength and structure and synthesizes the associated high resolution proton radiograph. The present tool’s numerical approach captures all relevant physics effects, including effects related to the formation of caustics. Electromagnetic fields can be imported from particle-in-cell or hydrodynamic codes in a streamlined fashion, and a library of electromagnetic field “primitives” is also provided. This latter capability allows users tomore » add a primitive, modify the field strength, rotate a primitive, and so on, while quickly generating a high resolution radiograph at each step. In this way, our tool enables the user to deconstruct features in a radiograph and interpret them in connection to specific underlying electromagnetic field elements. We show an example application of the tool in connection to experimental observations of the Weibel instability in counterstreaming plasmas, using ∼10{sup 8} particles generated from a realistic laser-driven point-like proton source, imaging fields which cover volumes of ∼10 mm{sup 3}. Insights derived from this application show that the tool can support understanding of HED plasmas.« less

Does transitioning from computed radiography (CR) to direct radiography (DR) with portable imaging systems affect workflow efficiency?

NASA Astrophysics Data System (ADS)

Gali, Raja L.; Roth, Christopher G.; Smith, Elizabeth; Dave, Jaydev K.

2018-03-01

In digital radiography, computed radiography (CR) technology is based on latent image capture by storage phosphors whereas direct radiography (DR) technology is based either on indirect conversion using a scintillator or direct conversion using a photoconductor. DR-based portable imaging systems may enhance workflow efficiency. The purpose of this work was to investigate changes in workflow efficiency at a tertiary healthcare center after transitioning from CR to DR technology for imaging with portable x-ray units. An IRB exemption was obtained. Data for all inpatient-radiographs acquired with portable x-ray units from July-2014 till June-2015 (period 1) with CR technology (AMX4 or AMX4+ portable unit from GE Healthcare, NX workstation from Agfa Healthcare for digitization), from July-2015 till June-2016 (period 2) with DR technology (Carestream DRX-Revolution x-ray units and DRX-1C image receptors) and from July-2016 till January-2017 (period 3; same DR technology) were extracted using Centricity RIS-IC (GE Healthcare). Duration between the imaging-examination scheduled time and completed time (timesch-com) was calculated and compared using non-parametric tests (between the three time periods with corrections for multiple comparisons; three time periods were used to identify if there were any other potential temporal trends not related to transitioning from CR to DR). IBM's SPSS package was used for statistical analysis. Overall data was obtained from 33131, 32194, and 18015 cases in periods 1, 2 and 3, respectively. Independent-Samples Kruskal-Wallis test revealed a statistically significant difference in timesch-com across the three time periods (χ2(2, n= 83,340) = 2053, p < 0.001). The timesch-com was highest for period 1 i.e., radiographs acquired with CR technology (median: 64 minutes) and it decreased significantly for radiographs acquired with DR technology in periods 2 (median: 49 minutes; p < 0.001) and 3 (median∶ 44 minutes; p < 0.001). Overall

Conversion from film to image plates for transfer method neutron radiography of nuclear fuel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Craft, Aaron E.; Papaioannou, Glen C.; Chichester, David L.

This paper summarizes efforts to characterize and qualify a computed radiography (CR) system for neutron radiography of irradiated nuclear fuel at Idaho National Laboratory (INL). INL has multiple programs that are actively developing, testing, and evaluating new nuclear fuels. Irradiated fuel experiments are subjected to a number of sequential post-irradiation examination techniques that provide insight into the overall behavior and performance of the fuel. One of the first and most important of these exams is neutron radiography, which provides more comprehensive information about the internal condition of irradiated nuclear fuel than any other non-destructive technique to date. Results from neutronmore » radiography are often the driver for subsequent examinations of the PIE program. Features of interest that can be evaluated using neutron radiography include irradiation-induced swelling, isotopic and fuel-fragment redistribution, plate deformations, and fuel fracturing. The NRAD currently uses the foil-film transfer technique with film for imaging fuel. INL is pursuing multiple efforts to advance its neutron imaging capabilities for evaluating irradiated fuel and other applications, including conversion from film to CR image plates. Neutron CR is the current state-of-the-art for neutron imaging of highly-radioactive objects. Initial neutron radiographs of various types of nuclear fuel indicate that radiographs can be obtained of comparable image quality currently obtained using film. This paper provides neutron radiographs of representative irradiated fuel pins along with neutron radiographs of standards that informed the qualification of the neutron CR system for routine use. Additionally, this paper includes evaluations of some of the CR scanner parameters and their effects on image quality.« less

Yield of chest radiography after removal of esophageal foreign bodies.

PubMed

Fisher, Jeremy; Mittal, Rohit; Hill, Sarah; Wulkan, Mark L; Clifton, Matthew S

2013-05-01

The aim of this study was to determine the benefit of routine postoperative chest radiography after removal of esophageal foreign bodies in children. Medical records were reviewed of all patients evaluated with an esophageal foreign body at a single children's hospital over 10 years. Operative records and imaging reports were reviewed for evidence of esophageal injury. Of 803 records identified, 690 were included. All underwent rigid esophagoscopy and foreign body removal. The most common items removed were coins (94%), food boluses (3%), and batteries (2%). The rate of esophageal injury was 1.3% (9 patients). No injuries were identified on chest radiographs done as routine or for concern of injury. Patients with operative findings suggestive of an esophageal injury (n = 105) were significantly more likely to have an injury (8.6% vs 0%, P = .0001). Of the 585 children who did not have physical evidence of injury, 40% (n = 235) received a routine chest radiograph. Regardless of the indication, no injuries were identified on chest films. We conclude that intraoperative findings during rigid esophagoscopy suggestive of an injury are predictive of esophageal perforation. Routine chest radiography is not warranted in children who do not meet this criterion. In patients with a concern for injury, we suggest that chest radiography should be deferred in favor of esophagram.

Flash x-ray radiography of argon jets in ambient air

NASA Astrophysics Data System (ADS)

Geiswiller, J.; Robert, E.; Huré, L.; Cachoncinlle, C.; Viladrosa, R.; Pouvesle, J. M.

1998-09-01

This paper describes the development and application of a soft x-ray flash radiography technique. A very compact soft x-ray flash source has been specially designed for these studies. The table-top x-ray source developed in this work emits strong doses, up to one roentgen at the output window, of x-ray photons, with most of them in the characteristic lines of the anode material (photon energy in the energy range 5-10 keV), in pulse of 20 ns FWHM with an x-ray emission zone smaller than 0957-0233/9/9/024/img1. All these characteristics make this source attractive for the x-ray radiography of high-speed phenomena, down to ten nanoseconds duration and/or for the media presenting weak absorption for the harder x-ray photons emitted by more conventional flash x-ray systems. Argon streams in ambient air were chosen as a typical case to enlighten the potentialities of this method. Single-shot radiographs of such an argon jet through rectangular nozzles were obtained. No attempt of quantitative measurement of local density in the argon stream has yet been performed, only the qualitative structure of the jet has been investigated. Nevertheless, these preliminary results enable us to state that the diagnostics of gaseous or plasma media, even at rather low pressures, can proceed using soft x-ray flash radiography.

Strategies for Characterizing the Sensory Environment: Objective and Subjective Evaluation Methods using the VisiSonic Real Space 64/5 Audio-Visual Panoramic Camera

DTIC Science & Technology

2017-11-01

ARL-TR-8205 ● NOV 2017 US Army Research Laboratory Strategies for Characterizing the Sensory Environment: Objective and...Subjective Evaluation Methods using the VisiSonic Real Space 64/5 Audio-Visual Panoramic Camera By Joseph McArdle, Ashley Foots, Chris Stachowiak, and...return it to the originator. ARL-TR-8205 ● NOV 2017 US Army Research Laboratory Strategies for Characterizing the Sensory

Applications of neutron radiography for the nuclear power industry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Craft, Aaron E.; Barton, John P.

The World Conference on Neutron Radiography (WCNR) and International Topical Meeting on Neutron Radiography (ITMNR) series have been running over 35 years. The most recent event, ITMNR-8, focused on industrial applications and was the first time this series was hosted in China. In China, more than twenty new nuclear power plants are in construction and plans have been announced to increase the nuclear capacity further by a factor of three within fifteen years. There are additional prospects in many other nations. Neutron tests were vital during previous developments of materials and components for nuclear power applications, as reported in thismore » conference series. For example a majority of the 140 papers in the Proceedings of the First WCNR are for the benefit of the nuclear power industry. Included are reviews of the diverse techniques being applied in Europe, Japan, the United States, and at many other centers. Many of those techniques are being utilized and advanced to the present time. Neutron radiography of irradiated nuclear fuel provides more comprehensive information about the internal condition of irradiated nuclear fuel than any other non-destructive technique to date. Applications include examination of nuclear waste, nuclear fuels, cladding, control elements, and other critical components. In this paper, the techniques developed and applied internationally for the nuclear power industry since the earliest years are reviewed, and the question is asked whether neutron test techniques can be of value in development of the present and future generations of nuclear power plants world-wide.« less

Muon radiography in Russia with emulsion technique. First experiments future perspectives

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aleksandrov, A. B.; Bagulya, A. V.; Chernyavsky, M. M.

Cosmic ray muon radiography is a novel technique for imaging the internal structures of massive objects. It exploits the capability of high energy muons from cosmic-rays in order to obtain a density map of investigated object and trying to guess information on the variation in the density distribution. Nuclear emulsions are tracking detectors well suited to be employed in this context since they have an excellent angular resolution (few mrad), they are cheap, compact and robust, easily transportable, able to work in harsh environments, and do not require power supply. This work presents the first successful results in the fieldmore » of muon radiography in Russia with nuclear emulsions.« less

No Value for Routine Chest Radiography in the Work-Up of Early Stage Cervical Cancer Patients

PubMed Central

Hoogendam, Jacob P.; Zweemer, Ronald P.; Verkooijen, Helena M.; de Jong, Pim A.; van den Bosch, Maurice A. A. J.; Verheijen, René H. M.; Veldhuis, Wouter B.

2015-01-01

Aim Evidence supporting the recommendation to include chest radiography in the work-up of all cervical cancer patients is limited. We investigated the diagnostic value of routine chest radiography in cervical cancer staging. Methods All consecutive cervical cancer patients who presented at our tertiary referral center in the Netherlands (January 2006 – September 2013), and for whom ≥6 months follow-up was available, were included. As part of the staging procedure, patients underwent a routine two-directional digital chest radiograph. Findings were compared to a composite reference standard consisting of all imaging studies and histology obtained during the 6 months following radiography. Results Of the 402 women who presented with cervical cancer, 288 (71.6%) underwent chest radiography and had ≥6 months follow-up. Early clinical stage (I/II) cervical cancer was present in 244/288 (84.7%) women, while 44 (15.3%) presented with advanced disease (stage III/IV). The chest radiograph of 1 woman – with advanced pre-radiograph stage (IVA) disease – showed findings consistent with pulmonary metastases. Radiographs of 7 other women – 4 early, 3 advanced stage disease – were suspicious for pulmonary metastases which was confirmed by additional imaging in only 1 woman (with pre-radiograph advanced stage (IIIB) disease) and excluded in 6 cases, including all women with early stage disease. In none of the 288 women were thoracic skeletal metastases identified on imaging or during 6 months follow up. Radiography was unremarkable in 76.4% of the study population, and showed findings unrelated to the cervical carcinoma in 21.2%. Conclusion Routine chest radiography was of no value for any of the early stage cervical cancer patients presenting at our tertiary center over a period of 7.7 years. PMID:26135733

No Value for Routine Chest Radiography in the Work-Up of Early Stage Cervical Cancer Patients.

PubMed

Hoogendam, Jacob P; Zweemer, Ronald P; Verkooijen, Helena M; de Jong, Pim A; van den Bosch, Maurice A A J; Verheijen, René H M; Veldhuis, Wouter B

2015-01-01

Evidence supporting the recommendation to include chest radiography in the work-up of all cervical cancer patients is limited. We investigated the diagnostic value of routine chest radiography in cervical cancer staging. All consecutive cervical cancer patients who presented at our tertiary referral center in the Netherlands (January 2006 - September 2013), and for whom ≥6 months follow-up was available, were included. As part of the staging procedure, patients underwent a routine two-directional digital chest radiograph. Findings were compared to a composite reference standard consisting of all imaging studies and histology obtained during the 6 months following radiography. Of the 402 women who presented with cervical cancer, 288 (71.6%) underwent chest radiography and had ≥6 months follow-up. Early clinical stage (I/II) cervical cancer was present in 244/288 (84.7%) women, while 44 (15.3%) presented with advanced disease (stage III/IV). The chest radiograph of 1 woman - with advanced pre-radiograph stage (IVA) disease - showed findings consistent with pulmonary metastases. Radiographs of 7 other women - 4 early, 3 advanced stage disease - were suspicious for pulmonary metastases which was confirmed by additional imaging in only 1 woman (with pre-radiograph advanced stage (IIIB) disease) and excluded in 6 cases, including all women with early stage disease. In none of the 288 women were thoracic skeletal metastases identified on imaging or during 6 months follow up. Radiography was unremarkable in 76.4% of the study population, and showed findings unrelated to the cervical carcinoma in 21.2%. Routine chest radiography was of no value for any of the early stage cervical cancer patients presenting at our tertiary center over a period of 7.7 years.

Dose measurements in intraoral radiography using thermoluminescent dosimeters

NASA Astrophysics Data System (ADS)

Azorín, C.; Azorín, J.; Aguirre, F.; Rivera, T.

2015-01-01

The use of X-ray in medicine demands to expose the patient and the professional to the lowest radiation doses available in agreement with ALARA philosophy. The reference level for intraoral dental radiography is 7 mGy and, in Mexico, a number of examinations of this type are performed annually. It is considered that approximately 25% of all the X-rays examinations carried out in our country correspond to intraoral radiographies. In other hand, most of the intraoral X-ray equipment correspond to conventional radiological systems using film, which are developed as much manual as automatically. In this work the results of determining the doses received by the patients in intraoral radiological examinations made with different radiological systems using LiF:Mg,Cu,P+PTFE thermoluminescent dosimeters are presented. In some conventional radiological systems using film, when films are developed manual or automatically, incident kerma up to 10.61 ± 0.74 mGv were determined. These values exceed that reference level suggested by the IAEA and in the Mexican standards for intraoral examinations.

Optical velocimetry at the Los Alamos Proton Radiography Facility

NASA Astrophysics Data System (ADS)

Tupa, Dale; Tainter, Amy; Neukirch, Levi; Hollander, Brian; Buttler, William; Holtkamp, David; The Los Alamos Proton Radiography Team Team

2016-05-01

The Los Alamos Proton Radiography Facility (pRad) employs a high-energy proton beam to image the properties and behavior of materials driven by high explosives. We will discuss features of pRad and describe some recent experiments, highlighting optical diagnostics for surface velocity measurements.

Experimental investigation of dynamic fragmentation of laser shock-loaded by soft recovery and X-ray radiography

NASA Astrophysics Data System (ADS)

Xin, Jianting; He, Weihua; Chu, Genbai; Gu, Yuqiu

2017-06-01

Dynamic fragmentation of metal under shock pressure is an important issue for both fundamental science and practical applications. And in recent decades, laser provides a promising shock loading technique for investigating the process of dynamic fragmentation under extreme condition application of high strain rate. Our group has performed experimental investigation of dynamic fragmentation under laser shock loading by soft recovery and X-ray radiography at SGC / ó prototype laser facility. The fragments under different loading pressures were recovered by PMP foam and analyzed by X-ray micro-tomography and the improved watershed method. The experiment result showed that the bilinear exponential distribution is more appropriate for representing the fragment size distribution. We also developed X-ray radiography technique. Owing to its inherent advantage over shadowgraph technique, X-ray radiography can potentially determine quantitatively material densities by measuring the X-ray transmission. Our group investigated dynamic process of microjetting by X-ray radiography technique, the recorded radiographic images show clear microjetting from the triangular grooves in the free surface of tin sample.

Lung nodule detection by microdose CT versus chest radiography (standard and dual-energy subtracted).

PubMed

Ebner, Lukas; Bütikofer, Yanik; Ott, Daniel; Huber, Adrian; Landau, Julia; Roos, Justus E; Heverhagen, Johannes T; Christe, Andreas

2015-04-01

The purpose of this study was to investigate the feasibility of microdose CT using a comparable dose as for conventional chest radiographs in two planes including dual-energy subtraction for lung nodule assessment. We investigated 65 chest phantoms with 141 lung nodules, using an anthropomorphic chest phantom with artificial lung nodules. Microdose CT parameters were 80 kV and 6 mAs, with pitch of 2.2. Iterative reconstruction algorithms and an integrated circuit detector system (Stellar, Siemens Healthcare) were applied for maximum dose reduction. Maximum intensity projections (MIPs) were reconstructed. Chest radiographs were acquired in two projections with bone suppression. Four blinded radiologists interpreted the images in random order. A soft-tissue CT kernel (I30f) delivered better sensitivities in a pilot study than a hard kernel (I70f), with respective mean (SD) sensitivities of 91.1%±2.2% versus 85.6%±5.6% (p=0.041). Nodule size was measured accurately for all kernels. Mean clustered nodule sensitivity with chest radiography was 45.7%±8.1% (with bone suppression, 46.1%±8%; p=0.94); for microdose CT, nodule sensitivity was 83.6%±9% without MIP (with additional MIP, 92.5%±6%; p<10(-3)). Individual sensitivities of microdose CT for readers 1, 2, 3, and 4 were 84.3%, 90.7%, 68.6%, and 45.0%, respectively. Sensitivities with chest radiography for readers 1, 2, 3, and 4 were 42.9%, 58.6%, 36.4%, and 90.7%, respectively. In the per-phantom analysis, respective sensitivities of microdose CT versus chest radiography were 96.2% and 75% (p<10(-6)). The effective dose for chest radiography including dual-energy subtraction was 0.242 mSv; for microdose CT, the applied dose was 0.1323 mSv. Microdose CT is better than the combination of chest radiography and dual-energy subtraction for the detection of solid nodules between 5 and 12 mm at a lower dose level of 0.13 mSv. Soft-tissue kernels allow better sensitivities. These preliminary results indicate that

Reliability of panoramic radiograph for carotid atheroma detection: a study in patients who fulfill the criteria for carotid endarterectomy.

PubMed

Damaskos, Spyros; Griniatsos, John; Tsekouras, Nikolaos; Georgopoulos, Sotirios; Klonaris, Chris; Bastounis, Elias; Tsiklakis, Kostas

2008-11-01

To evaluate the reliability of panoramic radiograph (PR) for carotid artery atheroma detection, by comparing its results with the carotid-vertebral digital subtraction angiography (DSA) findings, as well as with the detected calcium deposition in the carotid plaques, which were surgically resected, using direct radiographs. Forty consecutive patients suffering from carotid artery atherosclerotic occlusive disease confirmed by preoperative DSA, fulfilling the criteria for carotid endarterectomy, were operated on. Preoperatively, all of the patients had undergone PR, while postoperatively all of the surgically resected carotid plaques were radiographed using radiographic films and submitted to histologic examination. Compared with the DSA and the radiographic film findings, the PR results were classified as: 1) true-positive; 2) true-negative; 3) false-positive; or 4) false-negative. Panoramic radiograph has low sensitivity and specificity compared with the DSA findings and the direct radiographs results. However, a positive predictive value (PPV) of 100% per patient as well as for luminal stenosis >80% was documented. Even in the subgroup of patients who fulfill the criteria for carotid endarterectomy, PR has a low sensitivity and specificity; therefore, it cannot be considered to be a useful screening tool for atheroma detection in the general dental population. However, the 100% PPV per patient and for luminal stenosis >80%, indicates that positive calcification PR findings at the C(3)-C(4) region are highly suggestive for carotid artery atherosclerotic occlusive disease. Therefore, especially asymptomatic patients should be referred for further examination.

Pleural ultrasonography versus chest radiography for the diagnosis of pneumothorax: review of the literature and meta-analysis.

PubMed

Alrajab, Saadah; Youssef, Asser M; Akkus, Nuri I; Caldito, Gloria

2013-09-23

Ultrasonography is being increasingly utilized in acute care settings with expanding applications. Pneumothorax evaluation by ultrasonography is a fast, safe, easy and inexpensive alternative to chest radiographs. In this review, we provide a comprehensive analysis of the current literature comparing ultrasonography and chest radiography for the diagnosis of pneumothorax. We searched English-language articles in MEDLINE, EMBASE and Cochrane Library dealing with both ultrasonography and chest radiography for diagnosis of pneumothorax. In eligible studies that met strict inclusion criteria, we conducted a meta-analysis to evaluate the diagnostic accuracy of pleural ultrasonography in comparison with chest radiography for the diagnosis of pneumothorax. We reviewed 601 articles and selected 25 original research articles for detailed review. Only 13 articles met all of our inclusion criteria and were included in the final analysis. One study used lung sliding sign alone, 12 studies used lung sliding and comet tail signs, and 6 studies searched for lung point in addition to the other two signs. Ultrasonography had a pooled sensitivity of 78.6% (95% CI, 68.1 to 98.1) and a specificity of 98.4% (95% CI, 97.3 to 99.5). Chest radiography had a pooled sensitivity of 39.8% (95% CI, 29.4 to 50.3) and a specificity of 99.3% (95% CI, 98.4 to 100). Our meta-regression and subgroup analyses indicate that consecutive sampling of patients compared to convenience sampling provided higher sensitivity results for both ultrasonography and chest radiography. Consecutive versus nonconsecutive sampling and trauma versus nontrauma settings were significant sources of heterogeneity. In addition, subgroup analysis showed significant variations related to operator and type of probe used. Our study indicates that ultrasonography is more accurate than chest radiography for detection of pneumothorax. The results support the previous investigations in this field, add new valuable information

Optimum angle-cut of collimator for dense objects in high-energy proton radiography

NASA Astrophysics Data System (ADS)

Xu, Hai-Bo; Zheng, Na

2016-02-01

The use of minus identity lenses with an angle-cut collimator can achieve high contrast images in high-energy proton radiography. This article presents the principles of choosing the angle-cut aperture of the collimator for different energies and objects. Numerical simulation using the Monte Carlo code Geant4 has been implemented to investigate the entire radiography for the French test object. The optimum angle-cut apertures of the collimators are also obtained for different energies. Supported by NSAF (11176001) and Science and Technology Developing Foundation of China Academy of Engineering Physics (2012A0202006)

First experience with x-ray dark-field radiography for human chest imaging (Conference Presentation)

NASA Astrophysics Data System (ADS)

Noel, Peter B.; Willer, Konstantin; Fingerle, Alexander A.; Gromann, Lukas B.; De Marco, Fabio; Scherer, Kai H.; Herzen, Julia; Achterhold, Klaus; Gleich, Bernhard; Münzel, Daniela; Renz, Martin; Renger, Bernhard C.; Fischer, Florian; Braun, Christian; Auweter, Sigrid; Hellbach, Katharina; Reiser, Maximilian F.; Schröter, Tobias; Mohr, Jürgen; Yaroshenko, Andre; Maack, Hanns-Ingo; Pralow, Thomas; van der Heijden, Hendrik; Proksa, Roland; Köhler, Thomas; Wieberneit, Nataly; Rindt, Karsten; Rummeny, Ernst J.; Pfeiffer, Franz

2017-03-01

Purpose: To evaluate the performance of an experimental X-ray dark-field radiography system for chest imaging in humans and to compare with conventional diagnostic imaging. Materials and Methods: The study was institutional review board (IRB) approved. A single human cadaver (52 years, female, height: 173 cm, weight: 84 kg, chest circumference: 97 cm) was imaged within 24 hours post mortem on the experimental x-ray dark-field system. In addition, the cadaver was imaged on a clinical CT system to obtain a reference scan. The grating-based dark-field radiography setup was equipped with a set of three gratings to enable grating-based dark-field contrast x-ray imaging. The prototype operates at an acceleration voltage of up to 70 kVp and with a field-of-view large enough for clinical chest x-ray (>35 x 35 cm2). Results: It was feasible to extract x-ray dark-field signal of the whole human thorax, clearly demonstrating that human x-ray dark-field chest radiography is feasible. Lung tissue produced strong scattering, reflected in a pronounced x-ray dark-field signal. The ribcage and the backbone are less prominent than the lung but are also distinguishable. Finally, the soft tissue is not present in the dark-field radiography. The regions of the lungs affected by edema, as verified by CT, showed less dark-field signal compared to healthy lung tissue. Conclusion: Our results reveal the current status of translating dark-field imaging from a micro (small animal) scale to a macro (patient) scale. The performance of the experimental x-ray dark-field radiography setup offers, for the first time, obtaining multi-contrast chest x-ray images (attenuation and dark-field signal) from a human cadaver.

Mobile radiography services in nursing homes: a systematic review of residents' and societal outcomes.

PubMed

Kjelle, Elin; Lysdahl, Kristin Bakke

2017-03-23

Demographic changes are leading to an ageing population in Europe, and predict an increase in the number of nursing home residents over the next 30 years. Nursing home residents need specialised healthcare services such as radiology due to both chronic and acute illnesses. Mobile radiography, x-ray examinations performed in the nursing homes, may be a good way of providing services to this population. The aim of this systematic review was to identify the outcomes of mobile radiography services for nursing home residents and society. A systematic review based on searches in the Medline, Cochrane, PubMed, Embase and Svemed + databases was performed. Titles and abstracts were screened according to a predefined set of inclusion criteria: empirical studies in the geriatric population, and reports of mobile radiography services in a clinical setting. All publications were quality appraised using MMAT or CASP appraisal tools. Data were extracted using a summary table and results were narratively synthesised. Ten publications were included. Three overarching outcomes were identified: 1) reduced number of hospitalisations and outpatient examinations or treatments, 2) reduced number of transfers between nursing homes and hospitals and 3) increased access to x-ray examinations. These outcomes were interlinked with the more specific outcomes for residents and society reported in the literature. For residents there was a reduction in burdensome transfers and waiting time and adequate treatment and care increased. For society, released resources could be used more efficiently, and overall costs were reduced substantially. This review indicates that mobile radiography services for nursing home residents in the western world are of comparable quality to hospital-based examinations and have clear potential benefits. Mobile radiography reduced transfers to and from hospital, increased the number of examinations carried out and facilitated timely diagnosis and access to

Rotational seismology

USGS Publications Warehouse

Lee, William H K.

2016-01-01

Rotational seismology is an emerging study of all aspects of rotational motions induced by earthquakes, explosions, and ambient vibrations. It is of interest to several disciplines, including seismology, earthquake engineering, geodesy, and earth-based detection of Einstein’s gravitation waves.Rotational effects of seismic waves, together with rotations caused by soil–structure interaction, have been observed for centuries (e.g., rotated chimneys, monuments, and tombstones). Figure 1a shows the rotated monument to George Inglis observed after the 1897 Great Shillong earthquake. This monument had the form of an obelisk rising over 19 metres high from a 4 metre base. During the earthquake, the top part broke off and the remnant of some 6 metres rotated about 15° relative to the base. The study of rotational seismology began only recently when sensitive rotational sensors became available due to advances in aeronautical and astronomical instrumentations.

Diagnostic Accuracy of Ultrasonography and Radiography in Initial Evaluation of Chest Trauma Patients.

PubMed

Vafaei, Ali; Hatamabadi, Hamid Reza; Heidary, Kamran; Alimohammadi, Hosein; Tarbiyat, Mohammad

2016-01-01

Application of chest radiography for all multiple trauma patients is associated with a significant increase in total costs, exposure to radiation, and overcrowding of the emergency department. Ultrasound has been introduced as an alternative diagnostic tool in this regard. The aim of the present study is to compare the diagnostic accuracy of chest ultrasonography and radiography in detection of traumatic intrathoracic injuries. In the present prospective cross-sectional study, patients with traumatic intrathoracic injuries, who were referred to the emergency department from December 2013 to December 2014, were assessed. The patients underwent bedside ultrasound, radiographic and computed tomography (CT) scan examinations based on ATLS recommendations. Screening performance characteristics of ultrasonography and radiography were compared using SPSS 21.0. Chest CT scan was considered as gold standard. 152 chest trauma patients with a mean age of 31.4 ± 13.8 years (range: 4 ‒ 67), were enrolled (77.6% male). Chest CT scan showed pulmonary contusion in 48 (31.6%) patients, hemothorax in 29 (19.1%), and pneumothorax in 55 (36.2%) cases. Area under the ROC curve of ultrasonography in detection of pneumothorax, hemothorax, and pulmonary contusion were 0.91 (95% CI: 0.86‒0.96), 0.86 (95% CI: 0.78‒0.94), and 0.80 (95% CI: 0.736‒0.88), respectively. Area under the ROC curve of radiography was 0.80 (95% CI: 0.736‒0.87) for detection of pneumothorax, 0.77 (95% CI: 0.68‒0.86) for hemothorax, and 0.58 (95% CI: 0.5‒0.67) for pulmonary contusion. Comparison of areas under the ROC curve declared the significant superiority of ultrasonography in detection of pneumothorax (p = 0.02) and pulmonary contusion (p < 0.001). However, the diagnostic value of the two tests was equal in detection of hemothorax (p = 0.08). The results of the present study showed that ultrasonography is preferable to radiography in the initial evaluation of patients with traumatic injuries to the

5. INTERIOR VIEW, SHOWING A CONTROL ROOM INSIDE THE RADIOGRAPHY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. INTERIOR VIEW, SHOWING A CONTROL ROOM INSIDE THE RADIOGRAPHY ROOM; PASS-THROUGH FOR EXPOSED FILM ON RIGHT - Fort McCoy, Building No. T-1031, North side of South Tenth Avenue, Block 10, Sparta, Monroe County, WI

Proton Radiography of a Thermal Explosion in PBX9501

NASA Astrophysics Data System (ADS)

Smilowitz, L.; Henson, B. F.; Romero, J. J.; Sandstrom, M. M.; Asay, B. W.; Schwartz, C.; Saunders, A.; Merrill, F.; Morris, C.; Murray, M. M.; McNeil, W. V.; Marr-Lyon, M.; Rightley, P. M.

2007-12-01

The understanding of thermal explosions and burn propagation lags that of detonations and shock propagation. Diagnostics such as high energy radiography have been used to image shocks, but have been previously precluded from use in thermal explosions due to their stringent timing requirements: shock propagation can be synchronized to an external diagnostic while thermal explosion can not. This issue is solved by following the evolution of the ignition volume in a thermal explosion and using a laser pulse to provide a temperature jump in that central volume during the final thermal runaway leading to ignition. Thermal explosion experiments have been conducted at the Los Alamos Proton Radiography facility and have yielded images of the evolution of ignition, post-ignition burn propagation, and case failure in a radially confined cylinder of PBX 9501. This paper presents images taken during the hours long quasistatic heating, the final minutes of thermal runaway, and the post ignition burn propagation.

Proton radiography and tomography with application to proton therapy

PubMed Central

Allinson, N M; Evans, P M

2015-01-01

Proton radiography and tomography have long promised benefit for proton therapy. Their first suggestion was in the early 1960s and the first published proton radiographs and CT images appeared in the late 1960s and 1970s, respectively. More than just providing anatomical images, proton transmission imaging provides the potential for the more accurate estimation of stopping-power ratio inside a patient and hence improved treatment planning and verification. With the recent explosion in growth of clinical proton therapy facilities, the time is perhaps ripe for the imaging modality to come to the fore. Yet many technical challenges remain to be solved before proton CT scanners become commonplace in the clinic. Research and development in this field is currently more active than at any time with several prototype designs emerging. This review introduces the principles of proton radiography and tomography, their historical developments, the raft of modern prototype systems and the primary design issues. PMID:26043157

Sensitometric and archival evaluation of Kodak RA films in dental automatic processing.

PubMed

Thunthy, K H; Yeadon, W R; Winberg, R

1994-04-01

The Kodak Rapid Access System is an extension of the T-grain technology (T-Mat film). Unlike the T-Mat film, the T-Mat/Rapid Access film is forehardened by the addition of more hardener to the film emulsion. It can thus be processed rapidly in a Kodak Rapid Access medical processor in only 45 seconds dry-to-dry cycle by using the Kodak X-Omat RA/30 developer that does not contain a hardener. The absence of the hardener, glutaraldehyde, in the developer also makes this solution environmentally safer. In medical radiography, the T-Mat film has been replaced by the T-Mat/Rapid Access film. However, in dental extraoral radiography the T-Mat film is still being used because the processing solutions and the comparatively low temperatures of dental automatic processors are different from those used in medical radiography. This report shows that, for panoramic and other dental extraoral radiography, T-Mat films can be replaced by T-Mat/RA films by processing them in conventional Kodak X-Omat RP solutions using a dental automatic processing cycle. The differences in the sensitometric properties of the T-Mat and T-Mat/rapid Access films were negligible and therefore clinically insignificant. All films tested well for archival quality.

The evaluation of MCI, MI, PMI and GT on both genders with different age and dental status.

PubMed

Bozdag, G; Sener, S

2015-01-01

The aim of this study was to measure the mandibular cortical index (MCI), mental index (MI), panoramic mandibular index (PMI) and cortical bone thickness in the zone of the gonial angle (GT) in panoramic radiographies from a large sample of males and females and to determine how they relate to patients' age, gender and dental status. 910 panoramic radiographs were obtained and grouped into age, dental status and gender. The MCI, MI, PMI and GT were analysed. Remarkable differences were observed for MCI and GT regarding gender, age groups and dental status on both sides (p < 0.05). While age and dental status had an effect on the MI and PMI in females, dental status had an effect on the MI and PMI in males (p < 0.05). Also, gender had an effect on the MI and PMI (p < 0.05). The effects of age and tooth loss are different in females and males. In females, the harmful effects of tooth loss and age are more prominent according to the PMI and MI measurements. The effects of age and tooth loss in the GT and MCI measurements are similar, and these indices can be accepted as more reliable in studies including both genders.

The evaluation of MCI, MI, PMI and GT on both genders with different age and dental status

PubMed Central

Sener, S

2015-01-01

Objectives: The aim of this study was to measure the mandibular cortical index (MCI), mental index (MI), panoramic mandibular index (PMI) and cortical bone thickness in the zone of the gonial angle (GT) in panoramic radiographies from a large sample of males and females and to determine how they relate to patients' age, gender and dental status. Methods: 910 panoramic radiographs were obtained and grouped into age, dental status and gender. The MCI, MI, PMI and GT were analysed. Results: Remarkable differences were observed for MCI and GT regarding gender, age groups and dental status on both sides (p < 0.05). While age and dental status had an effect on the MI and PMI in females, dental status had an effect on the MI and PMI in males (p < 0.05). Also, gender had an effect on the MI and PMI (p < 0.05). Conclusions: The effects of age and tooth loss are different in females and males. In females, the harmful effects of tooth loss and age are more prominent according to the PMI and MI measurements. The effects of age and tooth loss in the GT and MCI measurements are similar, and these indices can be accepted as more reliable in studies including both genders. PMID:26133366

Reliability of landmark identification in cephalometric radiography acquired by a storage phosphor imaging system.

PubMed

Chen, Y-J; Chen, S-K; Huang, H-W; Yao, C-C; Chang, H-F

2004-09-01

To compare the cephalometric landmark identification on softcopy and hardcopy of direct digital cephalography acquired by a storage-phosphor (SP) imaging system. Ten digital cephalograms and their conventional counterpart, hardcopy on a transparent blue film, were obtained by a SP imaging system and a dye sublimation printer. Twelve orthodontic residents identified 19 cephalometric landmarks on monitor-displayed SP digital images with computer-aided method and on their hardcopies with conventional method. The x- and y-coordinates for each landmark, indicating the horizontal and vertical positions, were analysed to assess the reliability of landmark identification and evaluate the concordance of the landmark locations in softcopy and hardcopy of SP digital cephalometric radiography. For each of the 19 landmarks, the location differences as well as the horizontal and vertical components were statistically significant between SP digital cephalometric radiography and its hardcopy. Smaller interobserver errors on SP digital images than those on their hardcopies were noted for all the landmarks, except point Go in vertical direction. The scatter-plots demonstrate the characteristic distribution of the interobserver error in both horizontal and vertical directions. Generally, the dispersion of interobserver error on SP digital cephalometric radiography is less than that on its hardcopy with conventional method. The SP digital cephalometric radiography could yield better or comparable level of performance in landmark identification as its hardcopy, except point Go in vertical direction.

Calculation of the cardiothoracic ratio from portable anteroposterior chest radiography.

PubMed

Chon, Sung Bin; Oh, Won Sup; Cho, Jun Hwi; Kim, Sam Soo; Lee, Seung-Joon

2011-11-01

Cardiothoracic ratio (CTR), the ratio of cardiac diameter (CD) to thoracic diameter (TD), is a useful screening method to detect cardiomegaly, but is reliable only on posteroanterior chest radiography (chest PA). We performed this cross-sectional 3-phase study to establish reliable CTR from anteroposterior chest radiography (chest AP). First, CD(Chest PA)/CD(Chest AP) ratios were determined at different radiation distances by manipulating chest computed tomography to simulate chest PA and AP. CD(Chest PA) was inferred from multiplying CD(Chest AP) by this ratio. Incorporating this CD and substituting the most recent TD(Chest PA), we calculated the 'corrected' CTR and compared it with the conventional one in patients who took both the chest radiographies. Finally, its validity was investigated among the critically ill patients who performed portable chest AP. CD(Chest PA)/CD(Chest AP) ratio was {0.00099 × (radiation distance [cm])} + 0.79 (n = 61, r = 1.00, P < 0.001). The corrected CTR was highly correlated with the conventional one (n = 34, difference: 0.00016 ± 0.029; r = 0.92, P < 0.001). It was higher in congestive than non-congestive patients (0.53 ± 0.085; n = 38 vs 0.49 ± 0.061; n = 46, P = 0.006). Its sensitivity and specificity was 61% and 54%. In summary, reliable CTR can be calculated from chest AP with an available previous chest PA. This might help physicians detect congestive cardiomegaly for patients undergoing portable chest AP.

[Gonad protective effect of radiation protective apron in chest radiography].

PubMed

Hashimoto, Masatoshi; Kato, Hideyuki; Fujibuchi, Toshiou; Ochi, Shigehiro; Morita, Fuminori

2004-12-01

Depending on the facility, a radiation protective apron (protector) is used to protect the gonad from radiation exposure in chest radiography. To determine the necessity of using a protector during chest radiography, we measured the effect of the protector on the gonad in this study. First, using a human body phantom, we measured the absorbed dose of the female gonad with and without the protector, using a thermoluminescence dosimeter (TLD), and confirmed its protective effect. Using the protector, the absorbed dose was reduced to 28+/-2% and 39+/-4% for field sizes of 14 x 17 inch and 14 x 14 inch, respectively. Next, we used Monte Carlo simulation and confirmed, not only the validity of the actual measurement values, but also the fact that the influence of radiation on the absorbed dose of the gonad was mostly from scattered radiation from inside the body for the 14 x 17 inch field size, and also from the X-ray tube for the 14 x 14 inch field size. Although a certain protective effect is achieved by using the protector, the radiation dose to the gonad is only a few microGy even without a protector. Thus, the risk of a genetic effect would be as small as 10(-8). Given that acceptable risk is below 10(-6), we conclude the use of a radiation protective apron is not necessary for diagnostic chest radiography.

Calculation of the Cardiothoracic Ratio from Portable Anteroposterior Chest Radiography

PubMed Central

Chon, Sung Bin; Oh, Won Sup; Cho, Jun Hwi; Kim, Sam Soo

2011-01-01

Cardiothoracic ratio (CTR), the ratio of cardiac diameter (CD) to thoracic diameter (TD), is a useful screening method to detect cardiomegaly, but is reliable only on posteroanterior chest radiography (chest PA). We performed this cross-sectional 3-phase study to establish reliable CTR from anteroposterior chest radiography (chest AP). First, CDChest PA/CDChest AP ratios were determined at different radiation distances by manipulating chest computed tomography to simulate chest PA and AP. CDChest PA was inferred from multiplying CDChest AP by this ratio. Incorporating this CD and substituting the most recent TDChest PA, we calculated the 'corrected' CTR and compared it with the conventional one in patients who took both the chest radiographies. Finally, its validity was investigated among the critically ill patients who performed portable chest AP. CDChest PA/CDChest AP ratio was {0.00099 × (radiation distance [cm])} + 0.79 (n = 61, r = 1.00, P < 0.001). The corrected CTR was highly correlated with the conventional one (n = 34, difference: 0.00016 ± 0.029; r = 0.92, P < 0.001). It was higher in congestive than non-congestive patients (0.53 ± 0.085; n = 38 vs 0.49 ± 0.061; n = 46, P = 0.006). Its sensitivity and specificity was 61% and 54%. In summary, reliable CTR can be calculated from chest AP with an available previous chest PA. This might help physicians detect congestive cardiomegaly for patients undergoing portable chest AP. PMID:22065900

Application of Digital Radiography to Weld Inspection for the Space Shuttle External Fuel Tank

NASA Technical Reports Server (NTRS)

Ussery, Warren

2009-01-01

This slide presentation reviews NASA's use of digital radiography to inspect the welds of the external tanks used to hold the cryogenic fuels for the Space Shuttle Main Engines. NASA has had a goal of replacing a significant portion of film used to inspect the welds, with digital radiography. The presentation reviews the objectives for converting to a digital system from film, the characteristics of the digital system, the Probability of detection study, the qualification and implementation of the system.

Development of CT and 3D-CT Using Flat Panel Detector Based Real-Time Digital Radiography System

NASA Astrophysics Data System (ADS)

Ravindran, V. R.; Sreelakshmi, C.; Vibin, Vibin

2008-09-01

The application of Digital Radiography in the Nondestructive Evaluation (NDE) of space vehicle components is a recent development in India. A Real-time DR system based on amorphous silicon Flat Panel Detector has been developed for the NDE of solid rocket motors at Rocket Propellant Plant of VSSC in a few years back. The technique has been successfully established for the nondestructive evaluation of solid rocket motors. The DR images recorded for a few solid rocket specimens are presented in the paper. The Real-time DR system is capable of generating sufficient digital X-ray image data with object rotation for the CT image reconstruction. In this paper the indigenous development of CT imaging based on the Realtime DR system for solid rocket motor is presented. Studies are also carried out to generate 3D-CT image from a set of adjacent CT images of the rocket motor. The capability of revealing the spatial location and characterisation of defect is demonstrated by the CT and 3D-CT images generated.

Development of CT and 3D-CT Using Flat Panel Detector Based Real-Time Digital Radiography System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ravindran, V. R.; Sreelakshmi, C.; Vibin

2008-09-26

The application of Digital Radiography in the Nondestructive Evaluation (NDE) of space vehicle components is a recent development in India. A Real-time DR system based on amorphous silicon Flat Panel Detector has been developed for the NDE of solid rocket motors at Rocket Propellant Plant of VSSC in a few years back. The technique has been successfully established for the nondestructive evaluation of solid rocket motors. The DR images recorded for a few solid rocket specimens are presented in the paper. The Real-time DR system is capable of generating sufficient digital X-ray image data with object rotation for the CTmore » image reconstruction. In this paper the indigenous development of CT imaging based on the Realtime DR system for solid rocket motor is presented. Studies are also carried out to generate 3D-CT image from a set of adjacent CT images of the rocket motor. The capability of revealing the spatial location and characterisation of defect is demonstrated by the CT and 3D-CT images generated.« less

Urethral Stenting for Obstructive Uropathy Utilizing Digital Radiography for Guidance: Feasibility and Clinical Outcome in 26 Dogs.

PubMed

Radhakrishnan, A

2017-03-01

Urethral stent placement is an interventional treatment option to alleviate urethral outflow obstruction. It has been described utilizing fluoroscopy, but fluoroscopy is not as readily available in private practice as digital radiography. To describe the use of digital radiography for urethral stent placement in dogs with obstructive uropathy. Twenty-six client-owned dogs presented for dysuria associated with benign and malignant causes of obstructive uropathy that underwent urethral stent placement. Retrospective study. Causes of obstructive uropathy included transitional cell carcinoma, prostatic carcinoma, hemangiosarcoma, obstructive proliferative urethritis, compressive vaginal leiomyosarcoma, and detrusor-sphincter dyssynergia. Survival time range was 1-48 months (median, 5 months). All dogs were discharged from the hospital with urine outflow restored. Intraprocedural complications included guide wire penetration of the urethral wall in 1 dog and improper stent placement in a second dog. Both complications were successfully managed at the time of the procedure with no follow-up problems noted in either patient. Urethral stent placement can be successfully performed utilizing digital radiography. The complications experienced can be avoided by more cautious progression with each step through the procedure and serial radiography. The application of digital radiography may allow treatment of urethral obstruction to become more readily available. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Flemish general dental practitioners' knowledge of dental radiology

PubMed Central

Aps, J K M

2010-01-01

The aim of this study was to assess general dental practitioners' knowledge of dental radiography and radiation protection in order to alert the Belgian authorities and dental professional societies. Prior to attending a postgraduate course on intraoral radiology, general dental practitioners in Flanders, Belgium, were asked to fill in a questionnaire regarding the radiological equipment and the techniques they used for intraoral radiography. The availability and type of dental panoramic equipment were also assessed. A total of 374 questionnaires were available for this study. 15% of the attendants used radiographic equipment that was more than 27 years old and 43% reported equipment that operated with a clockwork timer. 32% and 75% respectively had no idea what the kV or mA settings were on their intraoral equipment. 5% were unaware which cone geometry or geometric technique (paralleling or bisecting angle technique) they were using. 81% claimed to be using a short cone technique. 47% did not know what collimation meant, whereas 40% stated that they were using circular collimation. 38% used digital intraoral image detectors (63% were photostimulable storage phosphorplate (PSPP)), but 16% were not sure about the type of sensor they were using (PSPP or solid-state sensors). 61% also had dental panoramic equipment available, 25% of which was digital (10% charge coupled device (CCD) and 15% PSPP). These results clearly indicate the need for continued education on this subject. The latter is an important signal to Belgian authorities and dental professional societies. PMID:20100924

Neutron collimator design of neutron radiography based on the BNCT facility

NASA Astrophysics Data System (ADS)

Yang, Xiao-Peng; Yu, Bo-Xiang; Li, Yi-Guo; Peng, Dan; Lu, Jin; Zhang, Gao-Long; Zhao, Hang; Zhang, Ai-Wu; Li, Chun-Yang; Liu, Wan-Jin; Hu, Tao; Lü, Jun-Guang

2014-02-01

For the research of CCD neutron radiography, a neutron collimator was designed based on the exit of thermal neutron of the Boron Neutron Capture Therapy (BNCT) reactor. Based on the Geant4 simulations, the preliminary choice of the size of the collimator was determined. The materials were selected according to the literature data. Then, a collimator was constructed and tested on site. The results of experiment and simulation show that the thermal neutron flux at the end of the neutron collimator is greater than 1.0×106 n/cm2/s, the maximum collimation ratio (L/D) is 58, the Cd-ratio(Mn) is 160 and the diameter of collimator end is 10 cm. This neutron collimator is considered to be applicable for neutron radiography.

Factors affecting general practitioners' decisions about plain radiography for back pain: implications for classification of guideline barriers--a qualitative study.

PubMed

Espeland, Ansgar; Baerheim, Anders

2003-03-24

General practitioners often diverge from clinical guidelines regarding spine radiography. This study aimed to identify and describe A) factors general practitioners consider may affect their decisions about ordering plain radiography for back pain and B) barriers to guideline adherence suggested by such factors. Focus group interviews regarding factors affecting ordering decisions were carried out on a diverse sample of Norwegian general practitioners and were analysed qualitatively. Results of this study and two qualitative studies from the Netherlands and USA on use of spine radiography were interpreted for barriers to guideline adherence. These were compared with an existing barrier classification system described by Dr Cabana's group. The factors which Norwegian general practitioners considered might affect their decisions about ordering plain radiography for back pain concerned the following broader issues: clinical ordering criteria, patients' wishes for radiography and the general practitioner's response, uncertainty, professional dignity, access to radiology services, perception of whether the patient really was ill, sense of pressure from other health care providers/social security, and expectations about the consequences of ordering radiography. The three studies suggested several attitude-related and external barriers as classified in a previously reported system described by Dr Cabana in another study. Identified barriers not listed in this system were: lack of expectancy that guideline adherence will lead to desired health care process, emotional difficulty with adherence, improper access to actual/alternative health care services, and pressure from health care providers/organisations. Our findings may help implement spine radiography guidelines. They also indicate that Cabana et al.'s barrier classification system needs extending. A revised system is proposed.

Reliability of panoramic ultrasound imaging in simultaneously examining muscle size and quality of the hamstring muscles in young, healthy males and females.

PubMed

Palmer, Ty B; Akehi, Kazuma; Thiele, Ryan M; Smith, Doug B; Thompson, Brennan J

2015-03-01

The purpose of this study was to examine the reliability of ultrasound (US) measures of cross-sectional area (CSA), muscle thickness (MT) and echo intensity (EI) of the hamstrings, with comparisons between males and females. In 20 healthy participants (10 males, 10 females), CSA, MT and EI were measured from panoramic US scans of the hamstrings on 2 separate days. The intra-class correlation coefficients and standard errors of measurement as a percentage of the mean for CSA, MT and EI ranged from 0.715 to 0.984 and from 3.145 to 12.541% in the males and from 0.724 to 0.977 and from 4.571 to 17.890% in the females, respectively. The males had greater CSAs and MTs and lower EIs than the females (p = 0.002-0.049), and significant relationships were observed between CSA and MT (r = 0.714-0.938, p ≤ 0.001-0.023). From an overall reliability standpoint, these findings suggest that panoramic US may be a reliable technique for examining muscle size and quality of the hamstrings in both males and females. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Binocular Interactions Underlying the Classic Optomotor Responses of Flying Flies

PubMed Central

Duistermars, Brian J.; Care, Rachel A.; Frye, Mark A.

2012-01-01

In response to imposed course deviations, the optomotor reactions of animals reduce motion blur and facilitate the maintenance of stable body posture. In flies, many anatomical and electrophysiological studies suggest that disparate motion cues stimulating the left and right eyes are not processed in isolation but rather are integrated in the brain to produce a cohesive panoramic percept. To investigate the strength of such inter-ocular interactions and their role in compensatory sensory–motor transformations, we utilize a virtual reality flight simulator to record wing and head optomotor reactions by tethered flying flies in response to imposed binocular rotation and monocular front-to-back and back-to-front motion. Within a narrow range of stimulus parameters that generates large contrast insensitive optomotor responses to binocular rotation, we find that responses to monocular front-to-back motion are larger than those to panoramic rotation, but are contrast sensitive. Conversely, responses to monocular back-to-front motion are slower than those to rotation and peak at the lowest tested contrast. Together our results suggest that optomotor responses to binocular rotation result from the influence of non-additive contralateral inhibitory as well as excitatory circuit interactions that serve to confer contrast insensitivity to flight behaviors influenced by rotatory optic flow. PMID:22375108

Digital Radiography Qualification of Tube Welding

NASA Technical Reports Server (NTRS)

Carl, Chad

2012-01-01

The Orion Project will be directing Lockheed Martin to perform orbital arc welding on commodities metallic tubing as part of the Multi Purpose Crew Vehicle assembly and integration process in the Operations and Checkout High bay at Kennedy Space Center. The current method of nondestructive evaluation is utilizing traditional film based x-rays. Due to the high number of welds that are necessary to join the commodities tubing (approx 470), a more efficient and expeditious method of nondestructive evaluation is desired. Digital radiography will be qualified as part of a broader NNWG project scope.

Comparison of Diagnostic Accuracy of Radiation Dose-Equivalent Radiography, Multidetector Computed Tomography and Cone Beam Computed Tomography for Fractures of Adult Cadaveric Wrists

PubMed Central

Neubauer, Jakob; Benndorf, Matthias; Reidelbach, Carolin; Krauß, Tobias; Lampert, Florian; Zajonc, Horst; Kotter, Elmar; Langer, Mathias; Fiebich, Martin; Goerke, Sebastian M.

2016-01-01

Purpose To compare the diagnostic accuracy of radiography, to radiography equivalent dose multidetector computed tomography (RED-MDCT) and to radiography equivalent dose cone beam computed tomography (RED-CBCT) for wrist fractures. Methods As study subjects we obtained 10 cadaveric human hands from body donors. Distal radius, distal ulna and carpal bones (n = 100) were artificially fractured in random order in a controlled experimental setting. We performed radiation dose equivalent radiography (settings as in standard clinical care), RED-MDCT in a 320 row MDCT with single shot mode and RED-CBCT in a device dedicated to musculoskeletal imaging. Three raters independently evaluated the resulting images for fractures and the level of confidence for each finding. Gold standard was evaluated by consensus reading of a high-dose MDCT. Results Pooled sensitivity was higher in RED-MDCT with 0.89 and RED-MDCT with 0.81 compared to radiography with 0.54 (P = < .004). No significant differences were detected concerning the modalities’ specificities (with values between P = .98). Raters' confidence was higher in RED-MDCT and RED-CBCT compared to radiography (P < .001). Conclusion The diagnostic accuracy of RED-MDCT and RED-CBCT for wrist fractures proved to be similar and in some parts even higher compared to radiography. Readers are more confident in their reporting with the cross sectional modalities. Dose equivalent cross sectional computed tomography of the wrist could replace plain radiography for fracture diagnosis in the long run. PMID:27788215

Comparison of radiography and magnetic resonance imaging for evaluating the extent of nasal neoplasia in dogs.

PubMed

Petite, A F B; Dennis, R

2006-09-01

Magnetic resonance imaging (MRI) is increasingly used in veterinary practice and, in some centres, is part of the diagnostic work-up of small animals with nasal disease. However, there are no published studies which critically evaluate the use of magnetic resonance imaging for this purpose. The purpose of this work was to assess the changes seen using magnetic resonance imaging and to compare them with radiography. The study included 12 dogs that had undergone both radiography and magnetic resonance imaging of the nasal cavity and had a histopathological diagnosis of malignant nasal neoplasia. Two pairs of board-certified radiologists scored the radiographs and the MRI scans, evaluating 10 signs of abnormality using a simple scoring system. Magnetic resonance imaging features were described in detail, and radiographic and magnetic resonance imaging scores for each sign as well as total scores were compared. Magnetic resonance imaging often showed that the tumour was more extensive than it had appeared on radiography but occasionally showed that radiographs had overestimated its size. Although radiography was reliable for assessment of the presence and size of a mass and for the extent of turbinate destruction, it usually failed to show occlusion of the major airway passages that were evident on magnetic resonance imaging. Extension of the tumour into the opposite nasal cavity, frontal sinus, orbit and cranial cavity was shown much better on magnetic resonance imaging. Minor but significant extension beyond the nasal cavity, which is important for treatment planning and prognosis, requires magnetic resonance imaging for demonstration, although radiography shows major changes reliably.

X-ray vector radiography of a human hand

NASA Astrophysics Data System (ADS)

Jud, Christoph; Braig, Eva; Dierolf, Martin; Eggl, Elena; Günther, Benedikt; Achterhold, Klaus; Gleich, Bernhard; Rummeny, Ernst; Noël, Peter; Pfeiffer, Franz; Münzel, Daniela

2017-03-01

Grating based x-ray phase-contrast reveals differential phase-contrast (DPC) and dark-field contrast (DFC) on top of the conventional absorption image. X-ray vector radiography (XVR) exploits the directional dependence of the DFC and yields the mean scattering strength, the degree of anisotropy and the orientation of scattering structures by combining several DFC-projections. Here, we perform an XVR of an ex vivo human hand specimen. Conventional attenuation images have a good contrast between the bones and the surrounding soft tissue. Within the bones, trabecular structures are visible. However, XVR detects subtler differences within the trabecular structure: there is isotropic scattering in the extremities of the phalanx in contrast to anisotropic scattering in its body. The orientation changes as well from relatively random in the extremities to an alignment along the longitudinal trabecular orientation in the body. In the other bones measured, a similar behavior was found. These findings indicate a deeper insight into the anatomical configuration using XVR compared to conventional radiography. Since microfractures cause a discontinuous trabecular structure, XVR could help to detect so-called radiographically occult fractures of the trabecular bones.

Effect of rotation on a rotating hot-wire sensor

NASA Technical Reports Server (NTRS)

Hah, C.; Lakshminarayana, B.

1978-01-01

An investigation was conducted to discern the effects of centrifugal and Coriolis forces on a rotating hot-wire. The probe was calibrated in a wind tunnel as well as in a rotating mode. The effect of rotation was found to be negligibly small. A small change in cold resistance (1.5%) was observed in the rotating wire. The rotation seems to have a negligible effect on the fluid mechanics, heat transfer and material characteristics of the wire. This is a significant conclusion in view of the potential application of the hot-wire probe in a rotating passage (such as turbomachinery).

A maximum likelihood method for high resolution proton radiography/proton CT

NASA Astrophysics Data System (ADS)

Collins-Fekete, Charles-Antoine; Brousmiche, Sébastien; Portillo, Stephen K. N.; Beaulieu, Luc; Seco, Joao

2016-12-01

Multiple Coulomb scattering (MCS) is the largest contributor to blurring in proton imaging. In this work, we developed a maximum likelihood least squares estimator that improves proton radiography’s spatial resolution. The water equivalent thickness (WET) through projections defined from the source to the detector pixels were estimated such that they maximizes the likelihood of the energy loss of every proton crossing the volume. The length spent in each projection was calculated through the optimized cubic spline path estimate. The proton radiographies were produced using Geant4 simulations. Three phantoms were studied here: a slanted cube in a tank of water to measure 2D spatial resolution, a voxelized head phantom for clinical performance evaluation as well as a parametric Catphan phantom (CTP528) for 3D spatial resolution. Two proton beam configurations were used: a parallel and a conical beam. Proton beams of 200 and 330 MeV were simulated to acquire the radiography. Spatial resolution is increased from 2.44 lp cm-1 to 4.53 lp cm-1 in the 200 MeV beam and from 3.49 lp cm-1 to 5.76 lp cm-1 in the 330 MeV beam. Beam configurations do not affect the reconstructed spatial resolution as investigated between a radiography acquired with the parallel (3.49 lp cm-1 to 5.76 lp cm-1) or conical beam (from 3.49 lp cm-1 to 5.56 lp cm-1). The improved images were then used as input in a photon tomography algorithm. The proton CT reconstruction of the Catphan phantom shows high spatial resolution (from 2.79 to 5.55 lp cm-1 for the parallel beam and from 3.03 to 5.15 lp cm-1 for the conical beam) and the reconstruction of the head phantom, although qualitative, shows high contrast in the gradient region. The proposed formulation of the optimization demonstrates serious potential to increase the spatial resolution (up by 65 % ) in proton radiography and greatly accelerate proton computed tomography reconstruction.

42 CFR Appendix G to Part 75 - Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography

Code of Federal Regulations, 2013 CFR

2013-10-01

... 42 Public Health 1 2013-10-01 2013-10-01 false Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography G Appendix G to Part 75 Public Health PUBLIC HEALTH SERVICE...—Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography The following section...

42 CFR Appendix G to Part 75 - Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography

Code of Federal Regulations, 2011 CFR

2011-10-01

... 42 Public Health 1 2011-10-01 2011-10-01 false Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography G Appendix G to Part 75 Public Health PUBLIC HEALTH SERVICE...—Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography The following section...

42 CFR Appendix G to Part 75 - Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography

Code of Federal Regulations, 2012 CFR

2012-10-01

... 42 Public Health 1 2012-10-01 2012-10-01 false Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography G Appendix G to Part 75 Public Health PUBLIC HEALTH SERVICE...—Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography The following section...

42 CFR Appendix G to Part 75 - Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography

Code of Federal Regulations, 2014 CFR

2014-10-01

... 42 Public Health 1 2014-10-01 2014-10-01 false Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography G Appendix G to Part 75 Public Health PUBLIC HEALTH SERVICE...—Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography The following section...

42 CFR Appendix G to Part 75 - Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography

Code of Federal Regulations, 2010 CFR

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography G Appendix G to Part 75 Public Health PUBLIC HEALTH SERVICE...—Standards for Licensing Dental Hygienists and Dental Assistants in Dental Radiography The following section...

Comparative study of dental anomalies assessed with panoramic radiographs of Down syndrome and non-Down syndrome patients.

PubMed

Mayoral-Trias, M A; Llopis-Perez, J; Puigdollers Pérez, A

2016-03-01

The aim of this study was to compare the prevalence of dental anomalies from panoramic radiographs of age-matched individuals with and without Down Syndrome (DS). This is a retrospective cross-sectional study. A group of 41 patients (19 female and 22 male) with Down Syndrome (DS), mean age 10.6 ± 1.4 and a control group of 42 non- DS patients (26 female and 16 male), mean age 11.1 ± 1.3 were studied. This study examined the medical history and a panoramic radiograph of each patient. The dental anomalies studied were agenesis of permanent teeth (except third molars), size and shape maxillary lateral anomalies and maxillary canine eruption path anomalies. The groups were compared using Mann-Whitney and Wilcoxon non-parametric tests (p<0.05). Rho Spearman correlation coefficient was applied for associations. Results Agenesis of one permanent tooth was found in 73.17% of DS subjects and two or more permanent teeth in more than 50% (p<0.001). Maxillary lateral incisor was the most frequently absent tooth followed by mandibular second premolar, mandibular lateral incisor, maxillary second premolar and mandibular central incisor. No significant differences were detected between maxilla and mandible on either side. No differences in gender were observed. Significant differences were found for size and shape anomalies of maxillary lateral incisors, as well as for canine eruption anomalies (p<0.05). No gender differences were observed for either variable. No association was found between these two variables in the DS group. More dental anomalies were present in the DS group than in the control group, which implied that DS patients need periodical dental and orthodontic supervision so as to prevent or control subsequent oral problems.

The use of intrathecal analgesia and contrast radiography as preoperative diagnostic methods for digital flexor tendon sheath pathology.

PubMed

Fiske-Jackson, A R; Barker, W H J; Eliashar, E; Foy, K; Smith, R K W

2013-01-01

The sensitivity of ultrasonography for the diagnosis of manica flexoria (MF) tears within the digital flexor tendon sheath (DFTS) is lower than for diagnosis of marginal tears of the deep digital flexor tendon (DDFT). Additional diagnostic tools would assist in appropriate decision making for either conservative or surgical management. To evaluate the improvement in lameness of horses with MF or DDFT tears following intrathecal analgesia and to assess the sensitivity and specificity of contrast radiography for the diagnosis of these tears. The case records of horses presented to a referral clinic over a 7-year period that underwent intrathecal diagnostic analgesia, or intrathecal analgesia and contrast radiography, of the DFTS with subsequent tenoscopy were examined. Fifty-three limbs had intrathecal diagnostic analgesia performed and 23 contrast tenograms were assessed in horses undergoing DFTS tenoscopy. Horses with DDFT tears were significantly more likely to respond positively to intrathecal diagnostic analgesia than those with MF tears (P = 0.02). Using contrast radiography, tears of the MF were predicted with an overall sensitivity of 96% and specificity of 80%; marginal tears of the DDFT were predicted with an overall sensitivity of 57% and specificity of 84%. The results of intrathecal analgesia of the DFTS in combination with contrast radiography have a high sensitivity for predicting MF tears. The sensitivity of contrast radiography for predicting tears of the DDFT is lower but the specificity remains high. Contrast radiography performed at the same time as intrathecal analgesia provides useful information regarding the presence of MF tears and DDFT tears, which can assist in the decision of whether to manage the lameness conservatively or with tenoscopic evaluation. © 2012 EVJ Ltd.

Development of fast neutron radiography system based on portable neutron generator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yi, Chia Jia, E-mail: gei-i-kani@hotmail.com; Nilsuwankosit, Sunchai, E-mail: sunchai.n@chula.ac.th

Due to the high installation cost, the safety concern and the immobility of the research reactors, the neutron radiography system based on portable neutron generator is proposed. Since the neutrons generated from a portable neutron generator are mostly the fast neutrons, the system is emphasized on using the fast neutrons for the purpose of conducting the radiography. In order to suppress the influence of X-ray produced by the neutron generator, a combination of a shielding material sandwiched between two identical imaging plates is used. A binary XOR operation is then applied for combining the information from the imaging plates. Themore » raw images obtained confirm that the X-ray really has a large effect and that XOR operation can help enhance the effect of the neutrons.« less

Cumulative radiation exposure and associated cancer risk estimates for scoliosis patients: Impact of repetitive full spine radiography.

PubMed

Law, Martin; Ma, Wang-Kei; Lau, Damian; Chan, Eva; Yip, Lawrance; Lam, Wendy

2016-03-01

To quantitatively evaluate the cumulative effective dose and associated cancer risk for scoliotic patients undergoing repetitive full spine radiography during their diagnosis and follow up periods. Organ absorbed doses of full spine exposed scoliotic patients at different age were computer simulated with the use of PCXMC software. Gender specific effective dose was then calculated with the ICRP-103 approach. Values of lifetime attributable cancer risk for patients exposed at different age were calculated for both patient genders and for Asian and Western population. Mathematical fitting for effective dose and for lifetime attributable cancer risk, as function of exposed age, was analytically obtained to quantitatively estimate patient cumulated effective dose and cancer risk. The cumulative effective dose of full spine radiography with posteroanterior and lateral projection for patients exposed annually at age between 5 and 30 years using digital radiography system was calculated as 15mSv. The corresponding cumulative lifetime attributable cancer risk for Asian and Western population was calculated as 0.08-0.17%. Female scoliotic patients would be at a statistically significant higher cumulated cancer risk than male patients under the same full spine radiography protocol. We demonstrate the use of computer simulation and analytic formula to quantitatively obtain the cumulated effective dose and cancer risk at any age of exposure, both of which are valuable information to medical personnel and patients' parents concern about radiation safety in repetitive full spine radiography. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

An atlas-based organ dose estimator for tomosynthesis and radiography

NASA Astrophysics Data System (ADS)

Hoye, Jocelyn; Zhang, Yakun; Agasthya, Greeshma; Sturgeon, Greg; Kapadia, Anuj; Segars, W. Paul; Samei, Ehsan

2017-03-01

The purpose of this study was to provide patient-specific organ dose estimation based on an atlas of human models for twenty tomosynthesis and radiography protocols. The study utilized a library of 54 adult computational phantoms (age: 18-78 years, weight 52-117 kg) and a validated Monte-Carlo simulation (PENELOPE) of a tomosynthesis and radiography system to estimate organ dose. Positioning of patient anatomy was based on radiographic positioning handbooks. The field of view for each exam was calculated to include relevant organs per protocol. Through simulations, the energy deposited in each organ was binned to estimate normalized organ doses into a reference database. The database can be used as the basis to devise a dose calculator to predict patient-specific organ dose values based on kVp, mAs, exposure in air, and patient habitus for a given protocol. As an example of the utility of this tool, dose to an organ was studied as a function of average patient thickness in the field of view for a given exam and as a function of Body Mass Index (BMI). For tomosynthesis, organ doses can also be studied as a function of x-ray tube position. This work developed comprehensive information for organ dose dependencies across tomosynthesis and radiography. There was a general exponential decrease dependency with increasing patient size that is highly protocol dependent. There was a wide range of variability in organ dose across the patient population, which needs to be incorporated in the metrology of organ dose.

Assessment of periodontal bone level revisited: a controlled study on the diagnostic accuracy of clinical evaluation methods and intra-oral radiography.

PubMed

Christiaens, Véronique; De Bruyn, Hugo; Thevissen, Eric; Koole, Sebastiaan; Dierens, Melissa; Cosyn, Jan

2018-01-01

The accuracy of analogue and especially digital intra-oral radiography in assessing interdental bone level needs further documentation. The aim of this study was to compare clinical and radiographic bone level assessment to intra-surgical bone level registration (1) and to identify the clinical variables rendering interdental bone level assessment inaccurate (2). The study sample included 49 interdental sites in 17 periodontitis patients. Evaluation methods included vertical relative probing attachment level (RAL-V), analogue and digital intra-oral radiography and bone sounding without and with flap elevation. The latter was considered the true bone level. Five examiners evaluated all radiographs. Significant underestimation of the true bone level was observed for all evaluation methods pointing to 2.7 mm on average for analogue radiography, 2.5 mm for digital radiography, 1.8 mm for RAL-V and 0.6 mm for bone sounding without flap elevation (p < 0.001). Radiographic underestimation of the true bone level was higher in the (pre)molar region (p ≤ 0.047) and increased with defect depth (p < 0.001). Variation between clinicians was huge (range analogue radiography 2.2-3.2 mm; range digital radiography 2.1-3.0 mm). All evaluation methods significantly underestimated the true bone level. Bone sounding was most accurate, whereas intra-oral radiographs were least accurate. Deep periodontal defects in the (pre)molar region were most underrated by intra-oral radiography. Bone sounding had the highest accuracy in assessing interdental bone level.

Comparison of digital tomosynthesis and chest radiography for the detection of pulmonary nodules: systematic review and meta-analysis.

PubMed

Kim, Jun H; Lee, Kyung H; Kim, Kyoung-Tae; Kim, Hyun J; Ahn, Hyeong S; Kim, Yeo J; Lee, Ha Y; Jeon, Yong S

2016-12-01

To compare the diagnostic accuracy of digital tomosynthesis (DTS) with that of chest radiography for the detection of pulmonary nodules by meta-analysis. A systematic literature search was performed to identify relevant original studies from 1 January 1 1976 to 31 August 31 2016. The quality of included studies was assessed by quality assessment of diagnostic accuracy studies-2. Per-patient data were used to calculate the sensitivity and specificity and per-lesion data were used to calculate the detection rate. Summary receiver-operating characteristic curves were drawn for pulmonary nodule detection. 16 studies met the inclusion criteria. 1017 patients on a per-patient basis and 2159 lesions on a per-lesion basis from 16 eligible studies were evaluated. The pooled patient-based sensitivity of DTS was 0.85 [95% confidence interval (CI) 0.83-0.88] and the specificity was 0.95 (0.93-0.96). The pooled sensitivity and specificity of chest radiography were 0.47 (0.44-0.51) and 0.37 (0.34-0.40), respectively. The per-lesion detection rate was 2.90 (95% CI 2.63-3.19). DTS has higher diagnostic accuracy than chest radiography for detection of pulmonary nodules. Chest radiography has low sensitivity but similar specificity, comparable with that of DTS. Advances in knowledge: DTS has higher diagnostic accuracy than chest radiography for the detection of pulmonary nodules.

Comparing diagnostic accuracy of bedside ultrasound and radiography for bone fracture screening in multiple trauma patients at the ED.

PubMed

Bolandparvaz, Shahram; Moharamzadeh, Payman; Jamali, Kazem; Pouraghaei, Mahboob; Fadaie, Maryam; Sefidbakht, Sepideh; Shahsavari, Kavous

2013-11-01

Long bone fractures are currently diagnosed using radiography, but radiography has some disadvantages (radiation and being time consuming). The present study compared the diagnostic accuracy of bedside ultrasound and radiography in multiple trauma patients at the emergency department (ED). The study assessed 80 injured patients with multiple trauma from February 2011 to July 2012. The patients were older than 18 years and triaged to the cardiopulmonary resuscitation ward of the ED. Bedside ultrasound and radiography were conducted for them. The findings were separately and blindly assessed by 2 radiologists. Sensitivity, specificity, the positive and negative predictive value, and κ coefficient were measured to assess the accuracy and validity of ultrasound as compared with radiography. The sensitivity of ultrasound for diagnosis of limb bone fractures was not high enough and ranged between 55% and 75% depending on the fracture site. The specificity of this diagnostic method had an acceptable range of 62% to 84%. Ultrasound negative prediction value was higher than other indices under study and ranged between 73% and 83%, but its positive prediction value varied between 33.3% and 71%. The κ coefficient for diagnosis of long bone fractures of upper limb (κ = 0.58) and upper limb joints (κ = 0.47) and long bones of lower limb (κ = 0.52) was within the medium range. However, the value for diagnosing fractures of lower limb joints (κ = 0.47) was relatively low. Bedside ultrasound is not a reliable method for diagnosing fractures of upper and lower limb bones compared with radiography. © 2013 Elsevier Inc. All rights reserved.

Rotational evolution of slow-rotator sequence stars

NASA Astrophysics Data System (ADS)

Lanzafame, A. C.; Spada, F.

2015-12-01

Context. The observed relationship between mass, age and rotation in open clusters shows the progressive development of a slow-rotator sequence among stars possessing a radiative interior and a convective envelope during their pre-main sequence and main-sequence evolution. After 0.6 Gyr, most cluster members of this type have settled on this sequence. Aims: The observed clustering on this sequence suggests that it corresponds to some equilibrium or asymptotic condition that still lacks a complete theoretical interpretation, and which is crucial to our understanding of the stellar angular momentum evolution. Methods: We couple a rotational evolution model, which takes internal differential rotation into account, with classical and new proposals for the wind braking law, and fit models to the data using a Monte Carlo Markov chain (MCMC) method tailored to the problem at hand. We explore to what extent these models are able to reproduce the mass and time dependence of the stellar rotational evolution on the slow-rotator sequence. Results: The description of the evolution of the slow-rotator sequence requires taking the transfer of angular momentum from the radiative core to the convective envelope into account. We find that, in the mass range 0.85-1.10 M⊙, the core-envelope coupling timescale for stars in the slow-rotator sequence scales as M-7.28. Quasi-solid body rotation is achieved only after 1-2 Gyr, depending on stellar mass, which implies that observing small deviations from the Skumanich law (P ∝ √{t}) would require period data of older open clusters than is available to date. The observed evolution in the 0.1-2.5 Gyr age range and in the 0.85-1.10 M⊙ mass range is best reproduced by assuming an empirical mass dependence of the wind angular momentum loss proportional to the convective turnover timescale and to the stellar moment of inertia. Period isochrones based on our MCMC fit provide a tool for inferring stellar ages of solar-like main

Visually Coupled Systems (VCS): The Virtual Panoramic Display (VPD) System

NASA Technical Reports Server (NTRS)

Kocian, Dean F.

1992-01-01

The development and impact is described of new visually coupled system (VCS) equipment designed to support engineering and human factors research in the military aircraft cockpit environment. VCS represents an advanced man-machine interface (MMI). Its potential to improve aircrew situational awareness seems enormous, but its superiority over the conventional cockpit MMI has not been established in a conclusive and rigorous fashion. What has been missing is a 'systems' approach to technology advancement that is comprehensive enough to produce conclusive results concerning the operational viability of the VCS concept and verify any risk factors that might be involved with its general use in the cockpit. The advanced VCS configuration described here, was ruggedized for use in military aircraft environments and was dubbed the Virtual Panoramic Display (VPD). It was designed to answer the VCS portion of the systems problem, and is implemented as a modular system whose performance can be tailored to specific application requirements. The overall system concept and the design of the two most important electronic subsystems that support the helmet mounted parts, a new militarized version of the magnetic helmet mounted sight and correspondingly similar helmet display electronics, are discussed in detail. Significant emphasis is given to illustrating how particular design features in the hardware improve overall system performance and support research activities.

Contrast-detail curves in chest radiography

NASA Astrophysics Data System (ADS)

Ogden, Kent; Scalzetti, Ernest; Huda, Walter; Saluja, Jasjeet; Lavallee, Robert

2005-04-01

We investigated how size and lesion location affect detection of simulated mass lesions in chest radiography. Simulated lesions were added to the center of 10 cm x 10 cm regions of digital chest radiographs, and used in 4-Alternative Forced-Choice (4-AFC) experiments. We determined the lesion contrast required to achieve a 92% correct detection rate I(92%). The mass size was manipulated to range from 1 to 10 mm, and we investigated lesion detection in the lung apex, hilar region, and in the sub-diaphragmatic region. In these experiments, the observer obtained I(92%) from randomized repeats obtained at each of seven lesion sizes, with the results plotted as I(92%) versus lesion size. In addition we investigated the effect of using the same background in the four 4-AFC experiments (twinned) and random backgrounds from the same anatomical region taken from 20 different radiographs. In all three anatomical regions investigated, the slopes of the contrast detail curve for the random background experiments were negative for lesion sizes less than 2.5, 3.5, and 5.5 mm in the hilar (slope of -0.26), apex (slope of -0.54), and sub-diaphragmatic (slope of -0.53) regions, respectively. For lesion sizes greater than these, the slopes were 0.34, 0.23, and 0.40 in the hilar, apex, and sub-diaphragmatic regions, respectively. The positive slopes for portions of the contrast-detail curves in chest radiography are a result of the anatomical background, and show that larger lesions require more contrast for visualization.

Neutron Focusing Mirrors for Neutron Radiography of Irradiated Nuclear Fuel at Idaho National Laboratory

NASA Astrophysics Data System (ADS)

Rai, Durgesh K.; Wu, Huarui; Abir, Muhammad; Giglio, Jeffrey; Khaykovich, Boris

Post irradiation examination (PIE) of samples irradiated in nuclear reactors is a challenging but necessary task for the development on novel nuclear power reactors. Idaho National Laboratory (INL) has neutron radiography capabilities, which are especially useful for the PIE of irradiated nuclear fuel. These capabilities are limited due to the extremely high gamma-ray radiation from the irradiated fuel, which precludes the use of standard digital detectors, in turn limiting the ability to do tomography and driving the cost of the measurements. In addition, the small 250 kW Neutron Radiography Reactor (NRAD) provides a relatively weak neutron flux, which leads to low signal-to-noise ratio. In this work, we develop neutron focusing optics suitable for the installation at NRAD. The optics would separate the sample and the detector, potentially allowing for the use of digital radiography detectors, and would provide significant intensity enhancement as well. The optics consist of several coaxial nested Wolter mirrors and is suited for polychromatic thermal neutron radiation. Laboratory Directed Research and Development program of Idaho National Laboratory.

Utility of a Newly Designed Film Holder for Premolar Bitewing Radiography.

PubMed

Safi, Yaser; Esmaeelinejad, Mohammad; Vasegh, Zahra; Valizadeh, Solmaz; Aghdasi, Mohammad Mehdi; Sarani, Omid; Afsahi, Mahmoud

2015-11-01

Bitewing radiography is a valuable technique for assessment of proximal caries, alveolar crest and periodontal status. Technical errors during radiography result in erroneous radiographic interpretation, misdiagnosis, possible mistreatment or unnecessary exposure of patient for taking a repeat radiograph. In this study, we aimed to evaluate the efficacy of a film holder modified from the conventional one and compared it with that of conventional film holder. Our study population comprised of 70 patients who were referred to the Radiology Department for bilateral premolar bitewing radiographs as requested by their attending clinician. Bitewing radiographs in each patient were taken using the newly designed holder in one side and the conventional holder in the other side. The acceptability of the two holders from the perspectives of the technician and patients was determined using a 0-20 point scale. The frequency of overlap and film positioning errors was calculated for each method. The conventional holder had greater acceptability among patients compared to the newly designed holder (mean score of 16.59 versus 13.37). From the technicians' point of view, the newly designed holder was superior to the conventional holder (mean score of 17.33 versus 16.44). The frequency of overlap was lower using the newly designed holder (p<0.001) and it allowed more accurate film positioning (p=0.005). The newly designed holder may facilitate the process of radiography for technicians and may be associated with less frequency of radiographic errors compared to the conventional holder.

Imaging Brunelleschi's cupola wall using muon scattering radiography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guardincerri, Elena

2015-09-16

This PowerPoint presentation describes the cupola's structure and current reinforcements, reasoning behind why muon radiography would be helpful. A demonstration project is described where a similar wall was constructed to illustrate the potential benefits to Italian authorities; Requirements and a potential plan were created and collaboration to make it happen was deemed to be possible among LANL, Toshiba, the Parma and Florence Universities and the Opera del Duomo,

Portable radiography: a reality and necessity for ISS and explorer-class missions.

PubMed

Lerner, David J; Parmet, Allen J

2015-02-01

On ISS missions and explorer class missions, unexpected medical and surgical emergencies could be disastrous. Lack of ability to rapidly assess and make critical decisions affects mission capability. Current imaging modalities on ISS consist only of ultrasound. There are many acute diagnoses which ultrasound alone cannot diagnose. Portable X-Ray imaging (radiography) technology has advanced far enough to where it is now small enough, cheap enough, and accurate enough to give diagnostic quality images sent wirelessly to the onboard computer and on Earth for interpretation while fitting in something the size of a briefcase. Although further research is warranted, Portable Radiography is an important addition to have on ISS and future Explorer Class Missions while maintaining a very small footprint.

Combining Radiography and Passive Measurements for Radiological Threat Detection in Cargo

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, Erin A.; White, Timothy A.; Jarman, Kenneth D.

Abstract Radiography is widely understood to provide information complimentary to passive detection: while not directly sensitive to radiological materials, radiography can reveal highly shielded regions which may mask a passive radiological signal. We present a method for combining radiographic and passive data which uses the radiograph to provide an estimate of scatter and attenuation for possible sources. This approach allows quantitative use of radiographic images without relying on image interpretation, and results in a probabilistic description of likely source locations and strengths. We present first results for this method for a simple modeled test case of a cargo container drivingmore » through a PVT portal. With this inversion approach, we address criteria for an integrated passive and radiographic screening system and how detection of SNM threats might be improved in such a system.« less

Measurement of Coolant in a Flat Heat Pipe Using Neutron Radiography

NASA Astrophysics Data System (ADS)

Mizuta, Kei; Saito, Yasushi; Goshima, Takashi; Tsutsui, Toshio

A newly developed flat heat pipe FGHPTM (Morex Kiire Co.) was experimentally investigated by using neutron radiography. The test sample of the FGHP heat spreader was 65 × 65 × 2 mm3 composed of several etched copper plates and pure water was used as the coolant. Neutron radiography was performed at the E-2 port of the Kyoto University Research Reactor (KUR). The coolant distributions in the wick area of the FGHP and its heat transfer characteristics were measured at heating conditions. Experimental results show that the coolant distributions depend slightly on its installation posture and that the liquid thickness in the wick region remains constant with increasing heat input to the FGHP. In addition, it is found that the wick surface does not dry out even in the vertical posture at present experimental conditions.

Factors affecting general practitioners' decisions about plain radiography for back pain: implications for classification of guideline barriers – a qualitative study

PubMed Central

Espeland, Ansgar; Baerheim, Anders

2003-01-01

Background General practitioners often diverge from clinical guidelines regarding spine radiography. This study aimed to identify and describe A) factors general practitioners consider may affect their decisions about ordering plain radiography for back pain and B) barriers to guideline adherence suggested by such factors. Methods Focus group interviews regarding factors affecting ordering decisions were carried out on a diverse sample of Norwegian general practitioners and were analysed qualitatively. Results of this study and two qualitative studies from the Netherlands and USA on use of spine radiography were interpreted for barriers to guideline adherence. These were compared with an existing barrier classification system described by Dr Cabana's group. Results The factors which Norwegian general practitioners considered might affect their decisions about ordering plain radiography for back pain concerned the following broader issues: clinical ordering criteria, patients' wishes for radiography and the general practitioner's response, uncertainty, professional dignity, access to radiology services, perception of whether the patient really was ill, sense of pressure from other health care providers/social security, and expectations about the consequences of ordering radiography. The three studies suggested several attitude-related and external barriers as classified in a previously reported system described by Dr Cabana in another study. Identified barriers not listed in this system were: lack of expectancy that guideline adherence will lead to desired health care process, emotional difficulty with adherence, improper access to actual/alternative health care services, and pressure from health care providers/organisations. Conclusions Our findings may help implement spine radiography guidelines. They also indicate that Cabana et al.'s barrier classification system needs extending. A revised system is proposed. PMID:12659640

Comparison of radiography and ultrasonography for diagnosing small-intestinal mechanical obstruction in vomiting dogs.

PubMed

Sharma, Ajay; Thompson, Margret S; Scrivani, Peter V; Dykes, Nathan L; Yeager, Amy E; Freer, Sean R; Erb, Hollis N

2011-01-01

A cross-sectional study was performed on acutely vomiting dogs to compare the accuracy of radiography and ultrasonography for the diagnosis of small-intestinal mechanical obstruction and to describe several radiographic and ultrasonographic signs to identify their contribution to the final diagnosis. The sample population consisted of 82 adult dogs and small-intestinal obstruction by foreign body was confirmed in 27/82 (33%) dogs by surgery or necropsy. Radiography produced a definitive result (obstructed or not obstructed) in 58/82 (70%) of dogs; ultrasonography produced a definitive result in 80/82 (97%) of dogs. On radiographs, a diagnosis of obstruction was based on detection of segmental small-intestinal dilatation, plication, or detection of a foreign body. Approximately 30% (8/27) of obstructed dogs did not have radiographic signs of segmental small-intestinal dilatation, of which 50% (4/8) were due to linear foreign bodies. The ultrasonographic diagnosis of small-intestinal obstruction was based on detection of an obstructive lesion, sonographic signs of plication or segmental, small-intestinal dilatation. The ultrasonographic presence or absence of moderate-to-severe intestinal diameter enlargement (due to lumen dilatation) of the jejunum (>1.5 cm) was a useful discriminatory finding and, when present, should prompt a thorough search for a cause of small-intestinal obstruction. In conclusion, both abdominal radiography and abdominal ultrasonography are accurate for diagnosing small-intestinal obstruction in vomiting dogs and either may be used depending on availability and examiner choice. Abdominal ultrasonography had greater accuracy, fewer equivocal results and provided greater diagnostic confidence compared with radiography. © 2010 Veterinary Radiology & Ultrasound.

Subtraction Radiography for the Diagnosis of Bone Lesions in Dogs.

DTIC Science & Technology

1984-05-31

Avail ander Journal of Periodontology Dist Special Ř 211 East Chicago Avenue Room 924 Chicago, IL 60611 Dear Sirs: I m submitting an original...research article titled "Subtraction Radiography for the Diagnosis of Bone Lesions in Dogs" solely to the Journal of Periodontology for review and