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Sample records for mice micro-computed tomography

  1. Quantification of lung fibrosis and emphysema in mice using automated micro-computed tomography.

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    Ellen De Langhe

    Full Text Available BACKGROUND: In vivo high-resolution micro-computed tomography allows for longitudinal image-based measurements in animal models of lung disease. The combination of repetitive high resolution imaging with fully automated quantitative image analysis in mouse models of lung fibrosis lung benefits preclinical research. This study aimed to develop and validate such an automated micro-computed tomography analysis algorithm for quantification of aerated lung volume in mice; an indicator of pulmonary fibrosis and emphysema severity. METHODOLOGY: Mice received an intratracheal instillation of bleomycin (n = 8, elastase (0.25 U elastase n = 9, 0.5 U elastase n = 8 or saline control (n = 6 for fibrosis, n = 5 for emphysema. A subset of mice was scanned without intervention, to evaluate potential radiation-induced toxicity (n = 4. Some bleomycin-instilled mice were treated with imatinib for proof of concept (n = 8. Mice were scanned weekly, until four weeks after induction, when they underwent pulmonary function testing, lung histology and collagen quantification. Aerated lung volumes were calculated with our automated algorithm. PRINCIPAL FINDINGS: Our automated image-based aerated lung volume quantification method is reproducible with low intra-subject variability. Bleomycin-treated mice had significantly lower scan-derived aerated lung volumes, compared to controls. Aerated lung volume correlated with the histopathological fibrosis score and total lung collagen content. Inversely, a dose-dependent increase in lung volume was observed in elastase-treated mice. Serial scanning of individual mice is feasible and visualized dynamic disease progression. No radiation-induced toxicity was observed. Three-dimensional images provided critical topographical information. CONCLUSIONS: We report on a high resolution in vivo micro-computed tomography image analysis algorithm that runs fully automated and allows quantification of aerated lung volume in mice. This

  2. Early Lung Adenocarcinoma in Mice: Micro-Computed Tomography Manifestations and Correlation with Pathology

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    Lin Deng

    2017-06-01

    Full Text Available Lung cancer is the most common fatal malignancy for both men and women and adenocarcinoma is the most common histologic type. Early diagnosis of lung cancer can significantly improve the survival rate of patients. This study aimed to investigate the micro-computed tomography (micro-CT manifestations of early lung adenocarcinoma (LAC in mice and to provide a new perspective for early clinical diagnosis. Early LAC models in 10 mice were established by subcutaneously injecting 1-methyl-3-nitro-1-nitrosoguanidine (MNNG solution. Micro-CT scan and multiple planar reconstruction (MPR were used for mouse lungs. Micro-CT features of early LAC, especially the relationships between tumor and bronchus, were analyzed and correlated with pathology. Micro-CT findings of early LAC were divided into three types: non-solid (n = 8, 6%, partly solid (n = 85, 64% and totally solid (n = 39, 30%. Tumor-bronchus relationships, which could be observed in 110 of 132(83% LAC, were classified into four patterns: type I (n = 16, 15%, bronchus was truncated at the margin of the tumor; type II (n = 33, 30%, bronchus penetrated into the tumor with tapered narrowing and interruption; type III (n = 38, 35%, bronchus penetrated into the tumor with a patent and intact lumen; type IV (n = 99, 90%, bronchus ran at the border of the tumor with an intact or compressed lumen. Micro-CT manifestations of early LAC correlated well with pathological findings. Micro-CT can clearly demonstrate the features of mouse early LAC and bronchus-tumor relationships, and can also provide a new tool and perspective for the study of early LAC.

  3. Micro-Computed Tomography Evaluation of Human Fat Grafts in Nude Mice

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    Chung, Michael T.; Hyun, Jeong S.; Lo, David D.; Montoro, Daniel T.; Hasegawa, Masakazu; Levi, Benjamin; Januszyk, Michael; Longaker, Michael T.

    2013-01-01

    Background Although autologous fat grafting has revolutionized the field of soft tissue reconstruction and augmentation, long-term maintenance of fat grafts is unpredictable. Recent studies have reported survival rates of fat grafts to vary anywhere between 10% and 80% over time. The present study evaluated the long-term viability of human fat grafts in a murine model using a novel imaging technique allowing for in vivo volumetric analysis. Methods Human fat grafts were prepared from lipoaspirate samples using the Coleman technique. Fat was injected subcutaneously into the scalp of 10 adult Crl:NU-Foxn1nu CD-1 male mice. Micro-computed tomography (CT) was performed immediately following injection and then weekly thereafter. Fat volume was rendered by reconstructing a three-dimensional (3D) surface through cubic-spline interpolation. Specimens were also harvested at various time points and sections were prepared and stained with hematoxylin and eosin (H&E), for macrophages using CD68 and for the cannabinoid receptor 1 (CB1). Finally, samples were explanted at 8- and 12-week time points to validate calculated micro-CT volumes. Results Weekly CT scanning demonstrated progressive volume loss over the time course. However, volumetric analysis at the 8- and 12-week time points stabilized, showing an average of 62.2% and 60.9% survival, respectively. Gross analysis showed the fat graft to be healthy and vascularized. H&E analysis and staining for CD68 showed minimal inflammatory reaction with viable adipocytes. Immunohistochemical staining with anti-human CB1 antibodies confirmed human origin of the adipocytes. Conclusions Studies assessing the fate of autologous fat grafts in animals have focused on nonimaging modalities, including histological and biochemical analyses, which require euthanasia of the animals. In this study, we have demonstrated the ability to employ micro-CT for 3D reconstruction and volumetric analysis of human fat grafts in a mouse model. Importantly

  4. Impaired bone formation in ovariectomized mice reduces implant integration as indicated by longitudinal in vivo micro-computed tomography.

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    Li, Zihui; Kuhn, Gisela; Schirmer, Michael; Müller, Ralph; Ruffoni, Davide

    2017-01-01

    Although osteoporotic bone, with low bone mass and deteriorated bone architecture, provides a less favorable mechanical environment than healthy bone for implant fixation, there is no general agreement on the impact of osteoporosis on peri-implant bone (re)modeling, which is ultimately responsible for the long term stability of the bone-implant system. Here, we inserted an implant in a mouse model mimicking estrogen deficiency-induced bone loss and we monitored with longitudinal in vivo micro-computed tomography the spatio-temporal changes in bone (re)modeling and architecture, considering the separate contributions of trabecular, endocortical and periosteal surfaces. Specifically, 12 week-old C57BL/6J mice underwent OVX/SHM surgery; 9 weeks after we inserted special metal-ceramics implants into the 6th caudal vertebra and we measured bone response with in vivo micro-CT weekly for the following 6 weeks. Our results indicated that ovariectomized mice showed a reduced ability to increase the thickness of the cortical shell close to the implant because of impaired peri-implant bone formation, especially at the periosteal surface. Moreover, we observed that healthy mice had a significantly higher loss of trabecular bone far from the implant than estrogen depleted animals. Such behavior suggests that, in healthy mice, the substantial increase in peri-implant bone formation which rapidly thickened the cortex to secure the implant may raise bone resorption elsewhere and, specifically, in the trabecular network of the same bone but far from the implant. Considering the already deteriorated bone structure of estrogen depleted mice, further bone loss seemed to be hindered. The obtained knowledge on the dynamic response of diseased bone following implant insertion should provide useful guidelines to develop advanced treatments for osteoporotic fracture fixation based on local and selective manipulation of bone turnover in the peri-implant region.

  5. Impaired bone formation in ovariectomized mice reduces implant integration as indicated by longitudinal in vivo micro-computed tomography.

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    Zihui Li

    Full Text Available Although osteoporotic bone, with low bone mass and deteriorated bone architecture, provides a less favorable mechanical environment than healthy bone for implant fixation, there is no general agreement on the impact of osteoporosis on peri-implant bone (remodeling, which is ultimately responsible for the long term stability of the bone-implant system. Here, we inserted an implant in a mouse model mimicking estrogen deficiency-induced bone loss and we monitored with longitudinal in vivo micro-computed tomography the spatio-temporal changes in bone (remodeling and architecture, considering the separate contributions of trabecular, endocortical and periosteal surfaces. Specifically, 12 week-old C57BL/6J mice underwent OVX/SHM surgery; 9 weeks after we inserted special metal-ceramics implants into the 6th caudal vertebra and we measured bone response with in vivo micro-CT weekly for the following 6 weeks. Our results indicated that ovariectomized mice showed a reduced ability to increase the thickness of the cortical shell close to the implant because of impaired peri-implant bone formation, especially at the periosteal surface. Moreover, we observed that healthy mice had a significantly higher loss of trabecular bone far from the implant than estrogen depleted animals. Such behavior suggests that, in healthy mice, the substantial increase in peri-implant bone formation which rapidly thickened the cortex to secure the implant may raise bone resorption elsewhere and, specifically, in the trabecular network of the same bone but far from the implant. Considering the already deteriorated bone structure of estrogen depleted mice, further bone loss seemed to be hindered. The obtained knowledge on the dynamic response of diseased bone following implant insertion should provide useful guidelines to develop advanced treatments for osteoporotic fracture fixation based on local and selective manipulation of bone turnover in the peri-implant region.

  6. Coronary artery wall imaging in mice using osmium tetroxide and micro-computed tomography (micro-CT)

    International Nuclear Information System (INIS)

    Pai, Vinay M.; Kozlowski, Megan; Donahue, Danielle; Miller, Elishiah; Xiao, Xianghui; Chen, Marcus Y.; Yu, Zu-Xi; Connelly, Patricia; Jeffries, Kenneth; Wen, Han

    2012-01-01

    The high spatial resolution of micro-computed tomography (micro-CT) is ideal for 3D imaging of coronary arteries in intact mouse heart specimens. Previously, micro-CT of mouse heart specimens utilized intravascular contrast agents that hardened within the vessel lumen and allowed a vascular cast to be made. However, for mouse coronary artery disease models, it is highly desirable to image coronary artery walls and highlight plaques. For this purpose, we describe an ex vivo contrast-enhanced micro-CT imaging technique based on tissue staining with osmium tetroxide (OsO 4 ) solution. As a tissue-staining contrast agent, OsO 4 is retained in the vessel wall and surrounding tissue during the fixation process and cleared from the vessel lumens. Its high X-ray attenuation makes the artery wall visible in CT. Additionally, since OsO 4 preferentially binds to lipids, it highlights lipid deposition in the artery wall. We performed micro-CT of heart specimens of 5- to 25-week-old C57BL/6 wild-type mice and 5- to 13-week-old apolipoprotein E knockout (apoE -/- ) mice at 10 μm resolution. The results show that walls of coronary arteries as small as 45 μm in diameter are visible using a table-top micro-CT scanner. Similar image clarity was achieved with 1/2000th the scan time using a synchrotron CT scanner. In 13-week-old apoE mice, lipid-rich plaques are visible in the aorta. Our study shows that the combination of OsO 4 and micro-CT permits the visualization of the coronary artery wall in intact mouse hearts.

  7. Intramembranous bone healing process subsequent to tooth extraction in mice: micro-computed tomography, histomorphometric and molecular characterization.

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    Vieira, Andreia Espindola; Repeke, Carlos Eduardo; Ferreira Junior, Samuel de Barros; Colavite, Priscila Maria; Biguetti, Claudia Cristina; Oliveira, Rodrigo Cardoso; Assis, Gerson Francisco; Taga, Rumio; Trombone, Ana Paula Favaro; Garlet, Gustavo Pompermaier

    2015-01-01

    Bone tissue has a significant potential for healing, which involves a significant the interplay between bone and immune cells. While fracture healing represents a useful model to investigate endochondral bone healing, intramembranous bone healing models are yet to be developed and characterized. In this study, a micro-computed tomography, histomorphometric and molecular (RealTimePCRarray) characterization of post tooth-extraction alveolar bone healing was performed on C57Bl/6 WT mice. After the initial clot dominance (0 h), the development of a provisional immature granulation tissue is evident (7 d), characterized by marked cell proliferation, angiogenesis and inflammatory cells infiltration; associated with peaks of growth factors (BMP-2-4-7,TGFβ1,VEGFa), cytokines (TNFα, IL-10), chemokines & receptors (CXCL12, CCL25, CCR5, CXCR4), matrix (Col1a1-2, ITGA4, VTN, MMP1a) and MSCs (CD105, CD106, OCT4, NANOG, CD34, CD146) markers expression. Granulation tissue is sequentially replaced by more mature connective tissue (14 d), characterized by inflammatory infiltrate reduction along the increased bone formation, marked expression of matrix remodeling enzymes (MMP-2-9), bone formation/maturation (RUNX2, ALP, DMP1, PHEX, SOST) markers, and chemokines & receptors associated with healing (CCL2, CCL17, CCR2). No evidences of cartilage cells or tissue were observed, strengthening the intramembranous nature of bone healing. Bone microarchitecture analysis supports the evolving healing, with total tissue and bone volumes as trabecular number and thickness showing a progressive increase over time. The extraction socket healing process is considered complete (21 d) when the dental socket is filled by trabeculae bone with well-defined medullary canals; it being the expression of mature bone markers prevalent at this period. Our data confirms the intramembranous bone healing nature of the model used, revealing parallels between the gene expression profile and the

  8. Intramembranous bone healing process subsequent to tooth extraction in mice: micro-computed tomography, histomorphometric and molecular characterization.

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    Andreia Espindola Vieira

    Full Text Available Bone tissue has a significant potential for healing, which involves a significant the interplay between bone and immune cells. While fracture healing represents a useful model to investigate endochondral bone healing, intramembranous bone healing models are yet to be developed and characterized. In this study, a micro-computed tomography, histomorphometric and molecular (RealTimePCRarray characterization of post tooth-extraction alveolar bone healing was performed on C57Bl/6 WT mice. After the initial clot dominance (0 h, the development of a provisional immature granulation tissue is evident (7 d, characterized by marked cell proliferation, angiogenesis and inflammatory cells infiltration; associated with peaks of growth factors (BMP-2-4-7,TGFβ1,VEGFa, cytokines (TNFα, IL-10, chemokines & receptors (CXCL12, CCL25, CCR5, CXCR4, matrix (Col1a1-2, ITGA4, VTN, MMP1a and MSCs (CD105, CD106, OCT4, NANOG, CD34, CD146 markers expression. Granulation tissue is sequentially replaced by more mature connective tissue (14 d, characterized by inflammatory infiltrate reduction along the increased bone formation, marked expression of matrix remodeling enzymes (MMP-2-9, bone formation/maturation (RUNX2, ALP, DMP1, PHEX, SOST markers, and chemokines & receptors associated with healing (CCL2, CCL17, CCR2. No evidences of cartilage cells or tissue were observed, strengthening the intramembranous nature of bone healing. Bone microarchitecture analysis supports the evolving healing, with total tissue and bone volumes as trabecular number and thickness showing a progressive increase over time. The extraction socket healing process is considered complete (21 d when the dental socket is filled by trabeculae bone with well-defined medullary canals; it being the expression of mature bone markers prevalent at this period. Our data confirms the intramembranous bone healing nature of the model used, revealing parallels between the gene expression profile and the

  9. Effect of micro-computed tomography voxel size and segmentation method on trabecular bone microstructure measures in mice

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    Blaine A. Christiansen

    2016-12-01

    Full Text Available Micro-computed tomography (μCT is currently the gold standard for determining trabecular bone microstructure in small animal models. Numerous parameters associated with scanning and evaluation of μCT scans can strongly affect morphologic results obtained from bone samples. However, the effect of these parameters on specific trabecular bone outcomes is not well understood. This study investigated the effect of μCT scanning with nominal voxel sizes between 6–30 μm on trabecular bone outcomes quantified in mouse vertebral body trabecular bone. Additionally, two methods for determining a global segmentation threshold were compared: based on qualitative assessment of 2D images, or based on quantitative assessment of image histograms. It was found that nominal voxel size had a strong effect on several commonly reported trabecular bone parameters, in particular connectivity density, trabecular thickness, and bone tissue mineral density. Additionally, the two segmentation methods provided similar trabecular bone outcomes for scans with small nominal voxel sizes, but considerably different outcomes for scans with larger voxel sizes. The Qualitatively Selected segmentation method more consistently estimated trabecular bone volume fraction (BV/TV and trabecular thickness across different voxel sizes, but the Histogram segmentation method more consistently estimated trabecular number, trabecular separation, and structure model index. Altogether, these results suggest that high-resolution scans be used whenever possible to provide the most accurate estimation of trabecular bone microstructure, and that the limitations of accurately determining trabecular bone outcomes should be considered when selecting scan parameters and making conclusions about inter-group variance or between-group differences in studies of trabecular bone microstructure in small animals. Keywords: Trabecular bone, Microstructure, Micro-computed tomography, Voxel size, Resolution

  10. The dynamic micro computed tomography at SSRF

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    Chen, R.; Xu, L.; Du, G.; Deng, B.; Xie, H.; Xiao, T.

    2018-05-01

    Synchrotron radiation micro-computed tomography (SR-μCT) is a critical technique for quantitative characterizing the 3D internal structure of samples, recently the dynamic SR-μCT has been attracting vast attention since it can evaluate the three-dimensional structure evolution of a sample. A dynamic μCT method, which is based on monochromatic beam, was developed at the X-ray Imaging and Biomedical Application Beamline at Shanghai Synchrotron Radiation Facility, by combining the compressed sensing based CT reconstruction algorithm and hardware upgrade. The monochromatic beam based method can achieve quantitative information, and lower dose than the white beam base method in which the lower energy beam is absorbed by the sample rather than contribute to the final imaging signal. The developed method is successfully used to investigate the compression of the air sac during respiration in a bell cricket, providing new knowledge for further research on the insect respiratory system.

  11. MicroComputed Tomography: Methodology and Applications

    International Nuclear Information System (INIS)

    Stock, Stuart R.

    2009-01-01

    Due to the availability of commercial laboratory systems and the emergence of user facilities at synchrotron radiation sources, studies of microcomputed tomography or microCT have increased exponentially. MicroComputed Technology provides a complete introduction to the technology, describing how to use it effectively and understand its results. The first part of the book focuses on methodology, covering experimental methods, data analysis, and visualization approaches. The second part addresses various microCT applications, including porous solids, microstructural evolution, soft tissue studies, multimode studies, and indirect analyses. The author presents a sufficient amount of fundamental material so that those new to the field can develop a relative understanding of how to design their own microCT studies. One of the first full-length references dedicated to microCT, this book provides an accessible introduction to field, supplemented with application examples and color images.

  12. Micro-computed tomography of pulmonary fibrosis in mice induced by adenoviral gene transfer of biologically active transforming growth factor-β1

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    Gauldie Jack

    2010-12-01

    Full Text Available Abstract Background Micro-computed tomography (micro-CT is a novel tool for monitoring acute and chronic disease states in small laboratory animals. Its value for assessing progressive lung fibrosis in mice has not been reported so far. Here we examined the importance of in vivo micro-CT as non-invasive tool to assess progression of pulmonary fibrosis in mice over time. Methods Pulmonary fibrosis was induced in mice by intratracheal delivery of an adenoviral gene vector encoding biologically active TGF-ß1 (AdTGF-ß1. Respiratory gated and ungated micro-CT scans were performed at 1, 2, 3, and 4 weeks post pulmonary adenoviral gene or control vector delivery, and were then correlated with respective histopathology-based Ashcroft scoring of pulmonary fibrosis in mice. Visual assessment of image quality and consolidation was performed by 3 observers and a semi-automated quantification algorithm was applied to quantify aerated pulmonary volume as an inverse surrogate marker for pulmonary fibrosis. Results We found a significant correlation between classical Ashcroft scoring and micro-CT assessment using both visual assessment and the semi-automated quantification algorithm. Pulmonary fibrosis could be clearly detected in micro-CT, image quality values were higher for respiratory gated exams, although differences were not significant. For assessment of fibrosis no significant difference between respiratory gated and ungated exams was observed. Conclusions Together, we show that micro-CT is a powerful tool to assess pulmonary fibrosis in mice, using both visual assessment and semi-automated quantification algorithms. These data may be important in view of pre-clinical pharmacologic interventions for the treatment of lung fibrosis in small laboratory animals.

  13. Cone-beam micro computed tomography dedicated to the breast.

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    Sarno, Antonio; Mettivier, Giovanni; Di Lillo, Francesca; Cesarelli, Mario; Bifulco, Paolo; Russo, Paolo

    2016-12-01

    We developed a scanner for micro computed tomography dedicated to the breast (BµCT) with a high resolution flat-panel detector and a microfocus X-ray tube. We evaluated the system spatial resolution via the 3D modulation transfer function (MTF). In addition to conventional absorption-based X-ray imaging, such a prototype showed capabilities for propagation-based phase-contrast and related edge enhancement effects in 3D imaging. The system limiting spatial resolution is 6.2mm -1 (MTF at 10%) in the vertical direction and 3.8mm -1 in the radial direction, values which compare favorably with the spatial resolution reached by mini focus breast CT scanners of other groups. The BµCT scanner was able to detect both microcalcification clusters and masses in an anthropomorphic breast phantom at a dose comparable to that of two-view mammography. The use of a breast holder is proposed in order to have 1-2min long scan times without breast motion artifacts. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

  14. Comparative micro computed tomography study of a vertebral body

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    Drews, Susanne; Beckmann, Felix; Herzen, Julia; Brunke, Oliver; Salmon, Phil; Friess, Sebastian; Laib, Andres; Koller, Bruno; Hemberger, Thomas; Müller-Gerbl, Magdalena; Müller, Bert

    2008-08-01

    Investigations of bony tissues are often performed using micro computed tomography based on X-rays, since the calcium distribution leads to superior contrast. Osteoporotic bone, for example, can be well compared with healthy one with respect to density and morphology. Degenerative and rheumatoid diseases usually start, however, at the bone-cartilage-interface, which is hardly accessible. The direct influence on the bone itself becomes only visible at later stage. For the development of suitable therapies against degenerative cartilage damages the exact three-dimensional description of the bone-cartilage interface is vital, as demonstrated for transplanted cartilage-cells or bone-cartilage-constructs in animal models. So far, the morphological characterization was restricted to magnetic resonance imaging (MRI) with poor spatial resolution or to time-consuming histological sectioning with appropriate spatial resolution only in two rather arbitrarily chosen directions. Therefore, one should develop μCT to extract the features of low absorbing cartilage. The morphology and the volume of the inter-vertebral cartilage disc of lumbar motion segments have been determined for one PMMA embedded specimen. Tomograms were recorded using nanotom® (Phoenix|x-ray, Wunstorf, Germany), μCT 35TM (Scanco Medical, Brütisellen, Switzerland), 1172TM and 1174TM (both Skyscan, Kontich, Belgium), as well as using the SRμCT at HASYLAB/DESY. Conventional and SRμCT can provide the morphology and the volume of cartilage between bones. Increasing the acquisition time, the signal-to-noise ratio becomes better and better but the prominent artifacts in conventional μCT as the result of inhomogeneously distributed bony tissue prevents the exact segmentation of cartilage. SRμCT allows segmenting the cartilage but requires long periods of expensive beam-time to obtain reasonable contrast.

  15. Comparison of denture models by means of micro computed tomography

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    Vögtlin, Christoph; Schulz, Georg; Deyhle, Hans; Jäger, Kurt; Liebrich, Thomas; Weikert, Sascha; Müller, Bert

    2012-10-01

    The production of dental inlays and crowns requires precise information on patients' teeth morphology. The conventional method is the preparation of impressions using mold materials, e.g. a silicone impression material. The disadvantage of this technique is the human choke impulse and the flavor of the material. These discomforts can be avoided by methods where a three-dimensional scanner is used for recording the teeth morphology. The present study reveals the accuracy of three model types, namely conventional impression, rapid prototyping using an oral scanner C.O.S., 3M (Schweiz) AG and milling from a proprietary resin using the oral scanner iTero, Straumann Holding AG. For each method five models were fabricated from a steel reference (standard). Using a nanotom m (phoenixǀx-ray, GE Sensing and Inspection Technologies GmbH), three-dimensional micro computed tomography data sets of the standard and the 15 models were recorded and landmark distances within the data sets were measured with sub-pixel accuracy. To verify these results a coordinate measuring machine (Leitz PMM 864, Hexagon Metrology GmbH) based on tactile detection was used for the measurement of the landmark distances, and a correction of the distances measured by the nanotom m was arranged. The nanotom data sets of the 15 models were also compared to the standard by means of a non-rigid registration algorithm. The calculated deformation field exhibited mean pixel displacement values of (0.19 +/- 0.09) mm for the C.O.S. models, (0.12 +/- 0.07) mm for the gypsum models and (0.19 +/- 0.12) mm for the i-Tero models.

  16. Nondestructive analysis of urinary calculi using micro computed tomography

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    Lingeman James E

    2004-12-01

    Full Text Available Abstract Background Micro computed tomography (micro CT has been shown to provide exceptionally high quality imaging of the fine structural detail within urinary calculi. We tested the idea that micro CT might also be used to identify the mineral composition of urinary stones non-destructively. Methods Micro CT x-ray attenuation values were measured for mineral that was positively identified by infrared microspectroscopy (FT-IR. To do this, human urinary stones were sectioned with a diamond wire saw. The cut surface was explored by FT-IR and regions of pure mineral were evaluated by micro CT to correlate x-ray attenuation values with mineral content. Additionally, intact stones were imaged with micro CT to visualize internal morphology and map the distribution of specific mineral components in 3-D. Results Micro CT images taken just beneath the cut surface of urinary stones showed excellent resolution of structural detail that could be correlated with structure visible in the optical image mode of FT-IR. Regions of pure mineral were not difficult to find by FT-IR for most stones and such regions could be localized on micro CT images of the cut surface. This was not true, however, for two brushite stones tested; in these, brushite was closely intermixed with calcium oxalate. Micro CT x-ray attenuation values were collected for six minerals that could be found in regions that appeared to be pure, including uric acid (3515 – 4995 micro CT attenuation units, AU, struvite (7242 – 7969 AU, cystine (8619 – 9921 AU, calcium oxalate dihydrate (13815 – 15797 AU, calcium oxalate monohydrate (16297 – 18449 AU, and hydroxyapatite (21144 – 23121 AU. These AU values did not overlap. Analysis of intact stones showed excellent resolution of structural detail and could discriminate multiple mineral types within heterogeneous stones. Conclusions Micro CT gives excellent structural detail of urinary stones, and these results demonstrate the feasibility

  17. Micro-computed tomography of pupal metamorphosis in the solitary bee Megachile rotundata

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    Insect metamorphosis involves a complex change in form and function, but most of these changes are internal and treated as a black box. In this study, we examined development of the solitary bee, Megachile rotundata, using micro-computed tomography (µCT) and digital volume analysis. We describe deve...

  18. The quantitative assessment of peri-implant bone responses using histomorphometry and micro-computed tomography.

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    Schouten, C.; Meijer, G.J.; Beucken, J.J.J.P van den; Spauwen, P.H.M.; Jansen, J.A.

    2009-01-01

    In the present study, the effects of implant design and surface properties on peri-implant bone response were evaluated with both conventional histomorphometry and micro-computed tomography (micro-CT), using two geometrically different dental implants (Screw type, St; Push-in, Pi) either or not

  19. Inside marginal adaptation of crowns by X-ray micro-computed tomography

    International Nuclear Information System (INIS)

    Dos Santos, T. M.; Lima, I.; Lopes, R. T.; Author, S. B. Jr.

    2015-01-01

    The objective of this work was to access dental arcade by using X-ray micro-computed tomography. For this purpose high resolution system was used and three groups were studied: Zirkonzahn CAD-CAM system, IPS e.max Press, and metal ceramic. The three systems assessed in this study showed results of marginal and discrepancy gaps clinically accepted. The great result of 2D and 3D evaluations showed that the used technique is a powerful method to investigate quantitative characteristics of dental arcade. (authors)

  20. Inside marginal adaptation of crowns by X-ray micro-computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Dos Santos, T. M.; Lima, I.; Lopes, R. T. [Nuclear Instrumentation Laboratory, Nuclear Engineering Program, Federal University of Rio de Janeiro, RJ, (Brazil); Author, S. B. Jr. [Department of Physics, Colorado State University, Ft. Collins, CO 80523, (United States)

    2015-07-01

    The objective of this work was to access dental arcade by using X-ray micro-computed tomography. For this purpose high resolution system was used and three groups were studied: Zirkonzahn CAD-CAM system, IPS e.max Press, and metal ceramic. The three systems assessed in this study showed results of marginal and discrepancy gaps clinically accepted. The great result of 2D and 3D evaluations showed that the used technique is a powerful method to investigate quantitative characteristics of dental arcade. (authors)

  1. Micro-computed tomography newly developed for in vivo small animal imaging

    International Nuclear Information System (INIS)

    Arai, Yoshinori; Ninomiya, Tadashi; Kato, Takafumi; Masuda, Yuji

    2005-01-01

    The aim of this paper is to report a newly developed micro-computed tomography system for in vivo use. The system was composed of a micro-focus X-ray tube and an image intensifier (I.I.), both of which rotated around the object stage. A guinea pig and a rat were examined. The anesthetized animal was set on the secure object stage. Images of the head of the guinea pig and the tibia knee joint of the rat were taken. In addition, an image of the rat's tail was taken. The reconstruction and the image viewing were carried out using I-View software. The voxel matrix was 512 x 512 x 384. The voxel sizes ranged from 10 x 10 x 10 μm to 100 x 100 x 100 μm. The exposure time was 17 s, and the reconstruction time was 150 s. The head of the guinea pig and the tibia/knee joint of the rat were observed clearly under 100-μm and 30μm voxels, respectively. The trabecular bone of the tail was also observed clearly under a 10 μm voxel. The newly developed micro-computed tomography system makes it possible to obtain images of anesthetized animals set on a secure object stage. Clear bone images of the small animals could be obtained within a short time. (author)

  2. Ceramic and polymeric dental onlays evaluated by photo-elasticity, optical coherence tomography, and micro-computed tomography

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    Sinescu, Cosmin; Negrutiu, Meda; Topala, Florin; Ionita, Ciprian; Negru, Radu; Fabriky, Mihai; Marcauteanu, Corina; Bradu, Adrian; Dobre, George; Marsavina, Liviu; Rominu, Mihai; Podoleanu, Adrian

    2011-10-01

    Dental onlays are restorations used to repair rear teeth that have a mild to moderate amount of decay. They can also be used to restore teeth that are cracked or fractured if the damage is not severe enough to require a dental crown. The use of onlays requires less tooth reduction than does the use of metal fillings. This allows dentists to conserve more of a patient's natural tooth structure in the treatment process. The aims of this study are to evaluate the biomechanical comportment of the dental onlays, by using the 3D photo elasticity method and to investigate the integrity of the structures and their fitting to the dental support. For this optical coherence tomography and micro-computed tomography were employed. Both methods were used to investigate 37 dental onlays, 17 integral polymeric and 20 integral ceramic. The results permit to observe materials defects inside the ceramic or polymeric onlays situate in the biomechanically tensioned areas that could lead to fracture of the prosthetic structure. Marginal fitting problems of the onlays related to the teeth preparations were presented in order to observe the possibility of secondary cavities. The resulted images from the optical coherence tomography were verified by the micro-computed tomography. In conclusion, the optical coherence tomography can be used as a clinical method in order to evaluate the integrity of the dental ceramic and polymeric onlays and to investigate the quality of the marginal fitting to the teeth preparations.

  3. Segmentation of Synchrotron Radiation micro-Computed Tomography Images using Energy Minimization via Graph Cuts

    Energy Technology Data Exchange (ETDEWEB)

    Meneses, Anderson A.M. [Federal University of Western Para (Brazil); Physics Institute, Rio de Janeiro State University (Brazil); Giusti, Alessandro [IDSIA (Dalle Molle Institute for Artificial Intelligence), University of Lugano (Switzerland); Almeida, Andre P. de, E-mail: apalmeid@gmail.com [Physics Institute, Rio de Janeiro State University (Brazil); Nuclear Engineering Program, Federal University of Rio de Janeiro (Brazil); Nogueira, Liebert; Braz, Delson [Nuclear Engineering Program, Federal University of Rio de Janeiro (Brazil); Almeida, Carlos E. de [Radiological Sciences Laboratory, Rio de Janeiro State University (Brazil); Barroso, Regina C. [Physics Institute, Rio de Janeiro State University (Brazil)

    2012-07-15

    The research on applications of segmentation algorithms to Synchrotron Radiation X-Ray micro-Computed Tomography (SR-{mu}CT) is an open problem, due to the interesting and well-known characteristics of SR images, such as the phase contrast effect. The Energy Minimization via Graph Cuts (EMvGC) algorithm represents state-of-art segmentation algorithm, presenting an enormous potential of application in SR-{mu}CT imaging. We describe the application of the algorithm EMvGC with swap move for the segmentation of bone images acquired at the ELETTRA Laboratory (Trieste, Italy). - Highlights: Black-Right-Pointing-Pointer Microstructures of Wistar rats' ribs are investigated with Synchrotron Radiation {mu}CT imaging. Black-Right-Pointing-Pointer The present work is part of a research on the effects of radiotherapy on the thoracic region. Black-Right-Pointing-Pointer Application of the Energy Minimization via Graph Cuts algorithm for segmentation is described.

  4. Micro-computed tomography imaging and analysis in developmental biology and toxicology.

    Science.gov (United States)

    Wise, L David; Winkelmann, Christopher T; Dogdas, Belma; Bagchi, Ansuman

    2013-06-01

    Micro-computed tomography (micro-CT) is a high resolution imaging technique that has expanded and strengthened in use since it was last reviewed in this journal in 2004. The technology has expanded to include more detailed analysis of bone, as well as soft tissues, by use of various contrast agents. It is increasingly applied to questions in developmental biology and developmental toxicology. Relatively high-throughput protocols now provide a powerful and efficient means to evaluate embryos and fetuses subjected to genetic manipulations or chemical exposures. This review provides an overview of the technology, including scanning, reconstruction, visualization, segmentation, and analysis of micro-CT generated images. This is followed by a review of more recent applications of the technology in some common laboratory species that highlight the diverse issues that can be addressed. Copyright © 2013 Wiley Periodicals, Inc.

  5. Image interpolation allows accurate quantitative bone morphometry in registered micro-computed tomography scans.

    Science.gov (United States)

    Schulte, Friederike A; Lambers, Floor M; Mueller, Thomas L; Stauber, Martin; Müller, Ralph

    2014-04-01

    Time-lapsed in vivo micro-computed tomography is a powerful tool to analyse longitudinal changes in the bone micro-architecture. Registration can overcome problems associated with spatial misalignment between scans; however, it requires image interpolation which might affect the outcome of a subsequent bone morphometric analysis. The impact of the interpolation error itself, though, has not been quantified to date. Therefore, the purpose of this ex vivo study was to elaborate the effect of different interpolator schemes [nearest neighbour, tri-linear and B-spline (BSP)] on bone morphometric indices. None of the interpolator schemes led to significant differences between interpolated and non-interpolated images, with the lowest interpolation error found for BSPs (1.4%). Furthermore, depending on the interpolator, the processing order of registration, Gaussian filtration and binarisation played a role. Independent from the interpolator, the present findings suggest that the evaluation of bone morphometry should be done with images registered using greyscale information.

  6. Segmentation of Synchrotron Radiation micro-Computed Tomography Images using Energy Minimization via Graph Cuts

    International Nuclear Information System (INIS)

    Meneses, Anderson A.M.; Giusti, Alessandro; Almeida, André P. de; Nogueira, Liebert; Braz, Delson; Almeida, Carlos E. de; Barroso, Regina C.

    2012-01-01

    The research on applications of segmentation algorithms to Synchrotron Radiation X-Ray micro-Computed Tomography (SR-μCT) is an open problem, due to the interesting and well-known characteristics of SR images, such as the phase contrast effect. The Energy Minimization via Graph Cuts (EMvGC) algorithm represents state-of-art segmentation algorithm, presenting an enormous potential of application in SR-μCT imaging. We describe the application of the algorithm EMvGC with swap move for the segmentation of bone images acquired at the ELETTRA Laboratory (Trieste, Italy). - Highlights: ► Microstructures of Wistar rats' ribs are investigated with Synchrotron Radiation μCT imaging. ► The present work is part of a research on the effects of radiotherapy on the thoracic region. ► Application of the Energy Minimization via Graph Cuts algorithm for segmentation is described.

  7. Application of micro-computed tomography to microstructure studies of the medicinal fungus Hericium coralloides.

    Science.gov (United States)

    Pallua, Johannes D; Kuhn, Volker; Pallua, Anton F; Pfaller, Kristian; Pallua, Anton K; Recheis, Wolfgang; Pöder, Reinhold

    2015-01-01

    The potential of 3-D nondestructive imaging techniques such as micro-computed tomography (micro-CT) was evaluated to study morphological patterns of the potential medicinal fungus Hericium coralloides (Basidiomycota). Micro-CT results were correlated with histological information gained from scanning electron microscopy (SEM) and light microscopy (LM). It is demonstrated that the combination of these imaging methods results in a more distinct picture of the morphology of the edible and potentially medicinal Hericium coralloides basidiomata. In addition we have created 3-D reconstructions and visualizations based on micro-CT imagery from a randomly selected part of the upper region of a fresh H. coralloides basidioma: Analyses for the first time allowed an approximation of the evolutionary effectiveness of this bizarrely formed basidioma type in terms of the investment of tissue biomass and its reproductive output (production of basidiospores). © 2015 by The Mycological Society of America.

  8. Imaging cellular and subcellular structure of human brain tissue using micro computed tomography

    Science.gov (United States)

    Khimchenko, Anna; Bikis, Christos; Schweighauser, Gabriel; Hench, Jürgen; Joita-Pacureanu, Alexandra-Teodora; Thalmann, Peter; Deyhle, Hans; Osmani, Bekim; Chicherova, Natalia; Hieber, Simone E.; Cloetens, Peter; Müller-Gerbl, Magdalena; Schulz, Georg; Müller, Bert

    2017-09-01

    Brain tissues have been an attractive subject for investigations in neuropathology, neuroscience, and neurobiol- ogy. Nevertheless, existing imaging methodologies have intrinsic limitations in three-dimensional (3D) label-free visualisation of extended tissue samples down to (sub)cellular level. For a long time, these morphological features were visualised by electron or light microscopies. In addition to being time-consuming, microscopic investigation includes specimen fixation, embedding, sectioning, staining, and imaging with the associated artefacts. More- over, optical microscopy remains hampered by a fundamental limit in the spatial resolution that is imposed by the diffraction of visible light wavefront. In contrast, various tomography approaches do not require a complex specimen preparation and can now reach a true (sub)cellular resolution. Even laboratory-based micro computed tomography in the absorption-contrast mode of formalin-fixed paraffin-embedded (FFPE) human cerebellum yields an image contrast comparable to conventional histological sections. Data of a superior image quality was obtained by means of synchrotron radiation-based single-distance X-ray phase-contrast tomography enabling the visualisation of non-stained Purkinje cells down to the subcellular level and automated cell counting. The question arises, whether the data quality of the hard X-ray tomography can be superior to optical microscopy. Herein, we discuss the label-free investigation of the human brain ultramorphology be means of synchrotron radiation-based hard X-ray magnified phase-contrast in-line tomography at the nano-imaging beamline ID16A (ESRF, Grenoble, France). As an example, we present images of FFPE human cerebellum block. Hard X-ray tomography can provide detailed information on human tissues in health and disease with a spatial resolution below the optical limit, improving understanding of the neuro-degenerative diseases.

  9. Detecting and visualizing internal 3D oleoresin in agarwood by means of micro-computed tomography

    International Nuclear Information System (INIS)

    Khairiah Yazid; Roslan Yahya; Mat Rosol Awang

    2012-01-01

    Detection and analysis of oleoresin is particularly significant since the commercial value of agarwood is related to the quantity of oleoresins that are present. A modern technique of non-destructive may reach the interior region of the wood. Currently, tomographic image data in particular is most commonly visualized in three dimensions using volume rendering. The aim of this paper is to explore the potential of high resolution non-destructive 3D visualization technique, X-ray micro-computed tomography, as imaging tools to visualize micro-structure oleoresin in agarwood. Investigations involving desktop X-ray micro-tomography system on high grade agarwood sample, performed at the Centre of Tomography in Nuclear Malaysia, demonstrate the applicability of the method. Prior to experiments, a reference test was conducted to stimulate the attenuation of oleoresin in agarwood. Based on the experiment results, micro-CT imaging with voxel size 7.0 μm is capable to of detecting oleoresin and pores in agarwood. This imaging technique, although sophisticated can be used for standard development especially in grading of agarwood for commercial activities. (author)

  10. In vivo quantitative assessment of myocardial structure, function, perfusion and viability using cardiac micro-computed tomography

    NARCIS (Netherlands)

    E.D. van Deel (Elza); Y. Ridwan (Yanto); van Vliet, J.N. (J. Nicole); Belenkov, S. (Sasha); J. Essers (Jeroen)

    2016-01-01

    textabstractThe use of Micro-Computed Tomography (MicroCT) for in vivo studies of small animals as models of human disease has risen tremendously due to the fact that MicroCT provides quantitative high-resolution three-dimensional (3D) anatomical data non-destructively and longitudinally. Most

  11. Quantitative in vivo micro-computed tomography for assessment of age-dependent changes in murine whole-body composition

    Directory of Open Access Journals (Sweden)

    Kim L. Beaucage

    2016-12-01

    Full Text Available Micro-computed tomography (micro-CT is used routinely to quantify skeletal tissue mass in small animal models. Our goal was to evaluate repeated in vivo micro-CT imaging for monitoring whole-body composition in studies of growth and aging in mice. Male mice from 2 to 52 weeks of age were anesthetized and imaged using an eXplore Locus Ultra and/or eXplore speCZT scanner. Images were reconstructed into 3D volumes, signal-intensity thresholds were used to classify each voxel as adipose, lean or skeletal tissue, and tissue masses were calculated from known density values. Images revealed specific changes in tissue distribution with growth and aging. Quantification showed biphasic increases in total CT-derived body mass, lean and skeletal tissue masses, consisting of rapid increases to 8 weeks of age, followed by slow linear increases to 52 weeks. In contrast, bone mineral density increased rapidly to a stable plateau at ~14 weeks of age. On the other hand, adipose tissue mass increased continuously with age. A micro-CT-derived total mass was calculated for each mouse and compared with gravimetrically measured mass, which differed on average by <3%. Parameters were highly reproducible for mice of the same age, but variability increased slightly with age. There was also good agreement in parameters for the same group of mice scanned on the eXplore Locus Ultra and eXplore speCZT systems. This study provides reference values for normative comparisons; as well, it demonstrates the usefulness of in vivo single-energy micro-CT scans to quantify whole-body composition in high-throughput studies of growth and aging in mice. Keywords: Adipose tissue, Bone mineral content, Bone mineral density, Growth, Lean tissue, Skeletal tissue

  12. Micro computed tomography features of laryngeal fractures in a case of fatal manual strangulation.

    Science.gov (United States)

    Fais, Paolo; Giraudo, Chiara; Viero, Alessia; Miotto, Diego; Bortolotti, Federica; Tagliaro, Franco; Montisci, Massimo; Cecchetto, Giovanni

    2016-01-01

    Cases of subtle fatal neck compression are often complicated by the lack of specificity of the post-mortem signs of asphyxia and by the lack of clear signs of neck compression. Herein we present a forensic case of a 45-year-old schizophrenic patient found on the floor of the bedroom of a psychiatric ward in cardiopulmonary arrest and who died after two days in a vegetative state. The deposition of the roommate of the deceased, who claimed responsibility for the killing of the victim by neck compression, was considered unreliable by the prosecutor. Autopsy, toxicological analyses, and multi-slice computed tomography (MSCT), micro computed tomography (micro-CT) and histology of the larynx complex were performed. Particularly, micro-CT analysis of the thyroid cartilage revealed the bilateral presence of ossified triticeous cartilages and the complete fragmentation of the right superior horn of the thyroid, but it additionally demonstrated a fracture on the contralateral superior horns, which was not clearly diagnosable at MSCT. On the basis of the evidence of intracartilaginous laryngeal hemorrhages and bilateral microfracture at the base of the superior horns of the larynx, the death was classified as a case of asphyxia due to manual strangulation. Micro-CT was confirmed as a useful tool in cases of subtle fatal neck compression, for the detection of minute laryngeal cartilage fractures, especially in complex cases with equivocal findings on MSCT. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  13. Three dimensional morphological studies of Larger Benthic Foraminifera at the population level using micro computed tomography

    Science.gov (United States)

    Kinoshita, Shunichi; Eder, Wolfgang; Woeger, Julia; Hohenegger, Johann; Briguglio, Antonino; Ferrandez-Canadell, Carles

    2015-04-01

    Symbiont-bearing larger benthic Foraminifera (LBF) are long-living marine (at least 1 year), single-celled organisms with complex calcium carbonate shells. Their morphology has been intensively studied since the middle of the nineteenth century. This led to a broad spectrum of taxonomic results, important from biostratigraphy to ecology in shallow water tropical to warm temperate marine palaeo-environments. However, it was necessary for the traditional investigation methods to cut or destruct specimens for analysing the taxonomically important inner structures. X-ray micro-computed tomography (microCT) is one of the newest techniques used in morphological studies. The greatest advantage is the non-destructive acquisition of inner structures. Furthermore, the running improve of microCT scanners' hard- and software provides high resolution and short time scans well-suited for LBF. Three-dimensional imaging techniques allow to select and extract each chamber and to measure easily its volume, surface and several form parameters used for morphometric analyses. Thus, 3-dimensional visualisation of LBF-tests is a very big step forward from traditional morphology based on 2-dimensional data. The quantification of chamber form is a great opportunity to tackle LBF structures, architectures and the bauplan geometry. The micrometric digital resolution is the only way to solve many controversies in phylogeny and evolutionary trends of LBF. For the present study we used micro-computed tomography to easily investigate the chamber number of every specimen from statistically representative part of populations to estimate population dynamics. Samples of living individuals are collected at monthly intervals from fixed locations. Specific preparation allows to scan up to 35 specimens per scan within 2 hours and to obtain the complete digital dataset for each specimen of the population. MicroCT enables thus a fast and precise count of all chambers built by the foraminifer from its

  14. Determination of strain fields in porous shape memory alloys using micro-computed tomography

    Science.gov (United States)

    Bormann, Therese; Friess, Sebastian; de Wild, Michael; Schumacher, Ralf; Schulz, Georg; Müller, Bert

    2010-09-01

    Shape memory alloys (SMAs) belong to 'intelligent' materials since the metal alloy can change its macroscopic shape as the result of the temperature-induced, reversible martensite-austenite phase transition. SMAs are often applied for medical applications such as stents, hinge-less instruments, artificial muscles, and dental braces. Rapid prototyping techniques, including selective laser melting (SLM), allow fabricating complex porous SMA microstructures. In the present study, the macroscopic shape changes of the SMA test structures fabricated by SLM have been investigated by means of micro computed tomography (μCT). For this purpose, the SMA structures are placed into the heating stage of the μCT system SkyScan 1172™ (SkyScan, Kontich, Belgium) to acquire three-dimensional datasets above and below the transition temperature, i.e. at room temperature and at about 80°C, respectively. The two datasets were registered on the basis of an affine registration algorithm with nine independent parameters - three for the translation, three for the rotation and three for the scaling in orthogonal directions. Essentially, the scaling parameters characterize the macroscopic deformation of the SMA structure of interest. Furthermore, applying the non-rigid registration algorithm, the three-dimensional strain field of the SMA structure on the micrometer scale comes to light. The strain fields obtained will serve for the optimization of the SLM-process and, more important, of the design of the complex shaped SMA structures for tissue engineering and medical implants.

  15. X-ray micro computed tomography for the visualization of an atherosclerotic human coronary artery

    Science.gov (United States)

    Matviykiv, Sofiya; Buscema, Marzia; Deyhle, Hans; Pfohl, Thomas; Zumbuehl, Andreas; Saxer, Till; Müller, Bert

    2017-06-01

    Atherosclerosis refers to narrowing or blocking of blood vessels that can lead to a heart attack, chest pain or stroke. Constricted segments of diseased arteries exhibit considerably increased wall shear stress, compared to the healthy ones. One of the possibilities to improve patient’s treatment is the application of nano-therapeutic approaches, based on shear stress sensitive nano-containers. In order to tailor the chemical composition and subsequent physical properties of such liposomes, one has to know precisely the morphology of critically stenosed arteries at micrometre resolution. It is often obtained by means of histology, which has the drawback of offering only two-dimensional information. Additionally, it requires the artery to be decalcified before sectioning, which might lead to deformations within the tissue. Micro computed tomography (μCT) enables the three-dimensional (3D) visualization of soft and hard tissues at micrometre level. μCT allows lumen segmentation that is crucial for subsequent flow simulation analysis. In this communication, tomographic images of a human coronary artery before and after decalcification are qualitatively and quantitatively compared. We analyse the cross section of the diseased human coronary artery before and after decalcification, and calculate the lumen area of both samples.

  16. Root canal morphology of primary molars: a micro-computed tomography study.

    Science.gov (United States)

    Fumes, A C; Sousa-Neto, M D; Leoni, G B; Versiani, M A; da Silva, L A B; da Silva, R A B; Consolaro, A

    2014-10-01

    This was to investigate the root canal morphology of primary molar teeth using micro-computed tomography. Primary maxillary (n = 20) and mandibular (n = 20) molars were scanned at a resolution of 16.7 μm and analysed regarding the number, location, volume, area, structured model index (SMI), area, roundness, diameters, and length of canals, as well as the thickness of dentine in the apical third. Data were statistically compared by using paired-sample t test, independent sample t test, and one-way analysis of variance with significance level set as 5%. Overall, no statistical differences were found between the canals with respect to length, SMI, dentine thickness, area, roundness, and diameter (p > 0.05). A double canal system was observed in the mesial and mesio-buccal roots of the mandibular and maxillary molars, respectively. The thickness in the internal aspect of the roots was lower than in the external aspect. Cross-sectional evaluation of the roots in the apical third showed flat-shaped canals in the mandibular molars and ribbon- and oval-shaped canals in the maxillary molars. External and internal anatomy of the primary first molars closely resemble the primary second molars. The reported data may help clinicians to obtain a thorough understanding of the morphological variations of root canals in primary molars to overcome problems related to shaping and cleaning procedures, allowing appropriate management strategies for root canal treatment.

  17. Finite element analysis of the mechanical properties of cellular aluminium based on micro-computed tomography

    International Nuclear Information System (INIS)

    Veyhl, C.; Belova, I.V.; Murch, G.E.; Fiedler, T.

    2011-01-01

    Research highlights: → Elastic and plastic anisotropy is observed for both materials → Both show qualitatively similar characteristics with quantitative differences → Distinctly higher mechanical properties for closed-cell foam → The 'big' and 'small' models show good agreement for the closed-cell foam. - Abstract: In the present paper, the macroscopic mechanical properties of open-cell M-Pore sponge (porosity of 91-93%) and closed-cell Alporas foam (porosity of 80-86%) are investigated. The complex geometry of these cellular materials is scanned by micro-computed tomography and used in finite element (FE) analysis. The mechanical properties are determined by uni-axial compression simulations in three perpendicular directions (x-, y- and z-direction). M-Pore and Alporas exhibit the same qualitative mechanical characteristics but with quantitative differences. In both cases, strong anisotropy is observed for Young's modulus and the 0.002 offset yield stress. Furthermore, for the investigated relative density range a linear dependence between relative density and mechanical properties is found. Finally, a distinctly higher Young's modulus and 0.002 offset yield stress is observed for Alporas.

  18. The microstructure of capsule containing self-healing materials: A micro-computed tomography study

    Energy Technology Data Exchange (ETDEWEB)

    Van Stappen, Jeroen, E-mail: Jeroen.Vanstappen@ugent.be [UGCT/PProGRess, Dept. of Geology, Ghent University, Krijgslaan 281 S8, B-9000 Ghent (Belgium); SIM vzw, Technologiepark 935, B-9052 Zwijnaarde (Belgium); Bultreys, Tom [UGCT/PProGRess, Dept. of Geology, Ghent University, Krijgslaan 281 S8, B-9000 Ghent (Belgium); Gilabert, Francisco A. [Mechanics of Materials and Structures, Dept. of Materials Science and Engineering, Ghent University, Technologiepark Zwijnaarde 903, B-9052 Zwijnaarde (Belgium); SIM vzw, Technologiepark 935, B-9052 Zwijnaarde (Belgium); Hillewaere, Xander K.D. [Polymer Chemistry Research Group, Dept. of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 S4-bis, B-9000 Ghent (Belgium); SIM vzw, Technologiepark 935, B-9052 Zwijnaarde (Belgium); Gómez, David Garoz [Mechanics of Materials and Structures, Dept. of Materials Science and Engineering, Ghent University, Technologiepark Zwijnaarde 903, B-9052 Zwijnaarde (Belgium); SIM vzw, Technologiepark 935, B-9052 Zwijnaarde (Belgium); Van Tittelboom, Kim [Magnel Laboratory for Concrete Research, Dept. of Structural Engineering, Ghent University, Technologiepark Zwijnaarde 904, B-9052 Ghent (Belgium); Dhaene, Jelle [UGCT/Radiation Physics, Dept. of Physics and Astronomy, Ghent University, Proeftuinstraat 86, B-9000 Ghent (Belgium); De Belie, Nele [Magnel Laboratory for Concrete Research, Dept. of Structural Engineering, Ghent University, Technologiepark Zwijnaarde 904, B-9052 Ghent (Belgium); Van Paepegem, Wim [Mechanics of Materials and Structures, Dept. of Materials Science and Engineering, Ghent University, Technologiepark Zwijnaarde 903, B-9052 Zwijnaarde (Belgium); Du Prez, Filip E. [Polymer Chemistry Research Group, Dept. of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 S4-bis, B-9000 Ghent (Belgium); Cnudde, Veerle [UGCT/PProGRess, Dept. of Geology, Ghent University, Krijgslaan 281 S8, B-9000 Ghent (Belgium)

    2016-09-15

    Autonomic self-healing materials are materials with built-in (micro-) capsules or vessels, which upon fracturing release healing agents in order to recover the material's physical and mechanical properties. In order to better understand and engineer these materials, a thorough characterization of the material's microstructural behavior is essential and often overlooked. In this context, micro-computed tomography (μCT) can be used to investigate the three dimensional distribution and (de)bonding of (micro-) capsules in their native state in a polymer system with self-healing properties. Furthermore, in-situ μCT experiments in a self-healing polymer and a self-healing concrete system can elucidate the breakage and leakage behavior of (micro-) capsules at the micrometer scale. While challenges related to image resolution and contrast complicate the characterization in specific cases, non-destructive 3D imaging with μCT is shown to contribute to the understanding of the link between the microstructure and the self-healing behavior of these complex materials. - Highlights: • μCT imaging allows for the analysis of microcapsule distribution patterns in self-healing materials. • μCT allows for qualitative and quantitative measurements of healing agent release from carriers in self-healing materials. • Experimental set-ups can be optimized by changing chemical compounds in the system to ensure maximum quality imaging.

  19. Micro-computed tomography and bond strength analysis of different root canal filling techniques

    Directory of Open Access Journals (Sweden)

    Juliane Nhata

    2014-01-01

    Full Text Available Introduction: The aim of this study was to evaluate the quality and bond strength of three root filling techniques (lateral compaction, continuous wave of condensation and Tagger′s Hybrid technique [THT] using micro-computed tomography (CT images and push-out tests, respectively. Materials and Methods: Thirty mandibular incisors were prepared using the same protocol and randomly divided into three groups (n = 10: Lateral condensation technique (LCT, continuous wave of condensation technique (CWCT, and THT. All specimens were filled with Gutta-percha (GP cones and AH Plus sealer. Five specimens of each group were randomly chosen for micro-CT analysis and all of them were sectioned into 1 mm slices and subjected to push-out tests. Results: Micro-CT analysis revealed less empty spaces when GP was heated within the root canals in CWCT and THT when compared to LCT. Push-out tests showed that LCT and THT had a significantly higher displacement resistance (P < 0.05 when compared to the CWCT. Bond strength was lower in apical and middle thirds than in the coronal thirds. Conclusions: It can be concluded that LCT and THT were associated with higher bond strengths to intraradicular dentine than CWCT. However, LCT was associated with more empty voids than the other techniques.

  20. Micro-computed tomography characterization of tissue engineering scaffolds: effects of pixel size and rotation step.

    Science.gov (United States)

    Cengiz, Ibrahim Fatih; Oliveira, Joaquim Miguel; Reis, Rui L

    2017-08-01

    Quantitative assessment of micro-structure of materials is of key importance in many fields including tissue engineering, biology, and dentistry. Micro-computed tomography (µ-CT) is an intensively used non-destructive technique. However, the acquisition parameters such as pixel size and rotation step may have significant effects on the obtained results. In this study, a set of tissue engineering scaffolds including examples of natural and synthetic polymers, and ceramics were analyzed. We comprehensively compared the quantitative results of µ-CT characterization using 15 acquisition scenarios that differ in the combination of the pixel size and rotation step. The results showed that the acquisition parameters could statistically significantly affect the quantified mean porosity, mean pore size, and mean wall thickness of the scaffolds. The effects are also practically important since the differences can be as high as 24% regarding the mean porosity in average, and 19.5 h and 166 GB regarding the characterization time and data storage per sample with a relatively small volume. This study showed in a quantitative manner the effects of such a wide range of acquisition scenarios on the final data, as well as the characterization time and data storage per sample. Herein, a clear picture of the effects of the pixel size and rotation step on the results is provided which can notably be useful to refine the practice of µ-CT characterization of scaffolds and economize the related resources.

  1. Micro-computed tomography visualization of the vestigial alimentary canal in adult oestrid flies.

    Science.gov (United States)

    Martín-Vega, D; Garbout, A; Ahmed, F; Ferrer, L M; Lucientes, J; Colwell, D D; Hall, M J R

    2018-02-16

    Oestrid flies (Diptera: Oestridae) do not feed during the adult stage as they acquire all necessary nutrients during the parasitic larval stage. The adult mouthparts and digestive tract are therefore frequently vestigial; however, morphological data on the alimentary canal in adult oestrid flies are scarce and a proper visualization of this organ system within the adult body is lacking. The present work visualizes the morphology of the alimentary canal in adults of two oestrid species, Oestrus ovis L. and Hypoderma lineatum (de Villiers), with the use of non-invasive micro-computed tomography (micro-CT) and compares it with the highly developed alimentary canal of the blow fly Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae). Both O. ovis and H. lineatum adults showed significant reductions of the cardia and the diameter of the digestive tract, an absence of the helicoidal portion of the midgut typical of other cyclorrhaphous flies, and a lack of crop and salivary glands. Given the current interest in the alimentary canal in adult dipterans in biomedical and developmental biology studies, further understanding of the morphology and development of this organ system in adult oestrids may provide valuable new insights in several areas of research. © 2018 The Royal Entomological Society.

  2. Visualization of haemophilic arthropathy in F8(-/-) rats by ultrasonography and micro-computed tomography

    DEFF Research Database (Denmark)

    Christensen, K R; Roepstorff, K; Petersen, M

    2017-01-01

    opportunities. Recently, a F8(-/-) rat model of HA was developed. The size of the rat allows for convenient and high resolution imaging of the joints, which could enable in vivo studies of HA development. AIM: To determine whether HA in the F8(-/-) rat can be visualized using ultrasonography (US) and micro......-computed tomography (μCT). METHODS: Sixty F8(-/-) and 20 wild-type rats were subjected to a single or two induced knee bleeds. F8(-/-) rats were treated with either recombinant human FVIII (rhFVIII) or vehicle before the induction of knee bleeds. Haemophilic arthropathy was visualized using in vivo US and ex vivo μCT......, and the observations correlated with histological evaluation. RESULTS: US and μCT detected pathologies in the knee related to HA. There was a strong correlation between disease severity determined by μCT and histopathology. rhFVIII treatment reduced the pathology identified with both imaging techniques. CONCLUSION: US...

  3. Analysis of micro computed tomography images; a look inside historic enamelled metal objects

    Science.gov (United States)

    van der Linden, Veerle; van de Casteele, Elke; Thomas, Mienke Simon; de Vos, Annemie; Janssen, Elsje; Janssens, Koen

    2010-02-01

    In this study the usefulness of micro-Computed Tomography (µ-CT) for the in-depth analysis of enamelled metal objects was tested. Usually investigations of enamelled metal artefacts are restricted to non-destructive surface analysis or analysis of cross sections after destructive sampling. Radiography, a commonly used technique in the field of cultural heritage studies, is limited to providing two-dimensional information about a three-dimensional object (Lang and Middleton, Radiography of Cultural Material, pp. 60-61, Elsevier-Butterworth-Heinemann, Amsterdam-Stoneham-London, 2005). Obtaining virtual slices and information about the internal structure of these objects was made possible by CT analysis. With this technique the underlying metal work was studied without removing the decorative enamel layer. Moreover visible defects such as cracks were measured in both width and depth and as of yet invisible defects and weaker areas are visualised. All these features are of great interest to restorers and conservators as they allow a view inside these objects without so much as touching them.

  4. Detection of marginal leakage of Class V restorations in vitro by micro-computed tomography.

    Science.gov (United States)

    Zhao, X Y; Li, S B; Gu, L J; Li, Y

    2014-01-01

    This in vitro study evaluated the efficacy of micro-computed tomography (CT) in marginal leakage detection of Class V restorations. Standardized Class V preparations with cervical margins in dentin and occlusal margins in enamel were made in 20 extracted human molars and restored with dental bonding agents and resin composite. All teeth were then immersed in 50% ammoniacal silver nitrate solution for 12 hours, followed by a developing solution for eight hours. Each restoration was scanned by micro-CT, the depth of marginal silver leakage in the central scanning section was measured, and the three-dimensional images of the silver leakage around each restoration were reconstructed. Afterward, all restorations were cut through the center and examined for leakage depth using a microscope. The silver leakage depth of each restoration obtained by the micro-CT and the microscope were compared for equivalency. The silver leakage depth in cervical walls observed by micro-CT and microscope showed no significant difference; however, in certain cases the judgment of leakage depth in the occlusal wall in micro-CT image was affected by adjacent enamel structure, providing less leakage depth than was observed with the microscope (pleakage around the Class V restorations with clear borders only in the dentin region. It can be concluded that micro-CT can detect nondestructively the leakage around a resin composite restoration in two and three dimensions, with accuracy comparable to that of the conventional microscope method in the dentin region but with inferior accuracy in the enamel region.

  5. The quantitative assessment of peri-implant bone responses using histomorphometry and micro-computed tomography.

    Science.gov (United States)

    Schouten, Corinne; Meijer, Gert J; van den Beucken, Jeroen J J P; Spauwen, Paul H M; Jansen, John A

    2009-09-01

    In the present study, the effects of implant design and surface properties on peri-implant bone response were evaluated with both conventional histomorphometry and micro-computed tomography (micro-CT), using two geometrically different dental implants (Screw type, St; Push-in, Pi) either or not surface-modified (non-coated, CaP-coated, or CaP-coated+TGF-beta1). After 12 weeks of implantation in a goat femoral condyle model, peri-implant bone response was evaluated in three different zones (inner: 0-500 microm; middle: 500-1000 microm; and outer: 1000-1500 microm) around the implant. Results indicated superiority of conventional histomorphometry over micro-CT, as the latter is hampered by deficits in the discrimination at the implant/tissue interface. Beyond this interface, both analysis techniques can be regarded as complementary. Histomorphometrical analysis showed an overall higher bone volume around St compared to Pi implants, but no effects of surface modification were observed. St implants showed lowest bone volumes in the outer zone, whereas inner zones were lowest for Pi implants. These results implicate that for Pi implants bone formation started from two different directions (contact- and distance osteogenesis). For St implants it was concluded that undersized implantation technique and loosening of bone fragments compress the zones for contact and distant osteogenesis, thereby improving bone volume at the interface significantly.

  6. Cochlear implant-related three-dimensional characteristics determined by micro-computed tomography reconstruction.

    Science.gov (United States)

    Ni, Yusu; Dai, Peidong; Dai, Chunfu; Li, Huawei

    2017-01-01

    To explore the structural characteristics of the cochlea in three-dimensional (3D) detail using 3D micro-computed tomography (mCT) image reconstruction of the osseous labyrinth, with the aim of improving the structural design of electrodes, the selection of stimulation sites, and the effectiveness of cochlear implantation. Three temporal bones were selected from among adult donors' temporal bone specimens. A micro-CT apparatus (GE eXplore) was used to scan three specimens with a voxel resolution of 45 μm. We obtained about 460 slices/specimen, which produced abundant data. The osseous labyrinth images of three specimens were reconstructed from mCT. The cochlea and its spiral characteristics were measured precisely using Able Software 3D-DOCTOR. The 3D images of the osseous labyrinth, including the cochlea, vestibule, and semicircular canals, were reconstructed. The 3D models of the cochlea showed the spatial relationships and surface structural characteristics. Quantitative data concerning the cochlea and its spiral structural characteristics were analyzed with regard to cochlear implantation. The 3D reconstruction of mCT images clearly displayed the detailed spiral structural characteristics of the osseous labyrinth. Quantitative data regarding the cochlea and its spiral structural characteristics could help to improve electrode structural design, signal processing, and the effectiveness of cochlear implantation. Clin. Anat. 30:39-43, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Influence of peri-implant artifacts on bone morphometric analysis with micro-computed tomography.

    Science.gov (United States)

    Song, Jin Wook; Cha, Jung Yul; Bechtold, Till Edward; Park, Young Chel

    2013-01-01

    To determine the optimal dilation pixel size distance from the mini-implant interface needed to compensate for the metal artifact on micro-computed tomography (micro-CT) for bone morphometric analysis. A total of 72 self-drilling mini-implants were placed into the buccal alveolar bone of six male beagle dogs. After 12 weeks of orthodontic loading, specimens were harvested and scanned with micro-CT (Skyscan 1076) at a resolution of 9 μm. Using the reload plug-in and dilation procedure of CTAn, the percentage of bone-implant contact (BIC) and bone volume density (BV/TV, bone volume/total volume), respectively, were measured from one to seven pixels from the metal implant surface. Each pixel size of dilation (PSD) were compared with that of a ground histologic section, and the optimal PSD for bone morphometric analysis using micro-CT was determined. BIC values from micro-CT analysis decreased when the PSD increased (P micro-CT showed the highest correlation coefficient with BIC from histologic slides when the PSD was 5 to 7 (P micro-CT showed a very high correlation with BV/TV from histologic slides in all ranges (P micro-CT, at least 5 PSD from the metal implant surface is needed.

  8. Effectiveness of rosiglitazone on bleomycin-induced lung fibrosis: Assessed by micro-computed tomography and pathologic scores

    International Nuclear Information System (INIS)

    Jin, Gong Yong; Bok, Se Mi; Han, Young Min; Chung, Myung Ja; Yoon, Kwon-Ha; Kim, So Ri; Lee, Yong Chul

    2012-01-01

    Peroxisome proliferator-activated receptor-γ (PPARγ) agonists exhibit potent anti-fibrotic effects in the lung and other tissues. Recently, micro-computed tomography (CT) has been a useful tool for the investigation of lung diseases in small animals and is now increasingly applied to visualize and quantify the pulmonary structures. However, there is little information on the assessment for therapeutic effects of PPARγ agonists on the pulmonary fibrosis in mice using micro-CT. This study was aimed to determine the capability of micro-CT in examining the effects of rosiglitazone on pulmonary fibrosis. We used a murine model of bleomycin-induced lung fibrosis to evaluate the feasibility of micro-CT in evaluating the therapeutic potential of rosiglitazone on pulmonary fibrosis, comparing with pathologic scores. On micro-CT findings, ground glass opacity (80%) and consolidation (20%) were observed predominantly at 3 weeks after the instillation of bleomycin, and the radiologic features became more complex at 6 weeks. In bleomycin-instilled mice treated with rosiglitazone, the majority (80%) showed normal lung features on micro-CT. Radiological-pathologic correlation analyses revealed that ground glass opacity and consolidation were correlated closely with acute inflammation, while reticular opacity was well correlated with histological honeycomb appearance. These results demonstrate that rosiglitazone displays a protective effect on pulmonary fibrosis in mice and that the visualization of bleomycin-induced pulmonary fibrosis using micro-CT is satisfactory to assess the effects of rosiglitazone. It implies that micro-CT can be applied to evaluate therapeutic efficacies of a variety of candidate drugs for lung diseases.

  9. Effectiveness of rosiglitazone on bleomycin-induced lung fibrosis: Assessed by micro-computed tomography and pathologic scores

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Gong Yong; Bok, Se Mi; Han, Young Min [Department of Radiology, Chonbuk National University Medical School, Jeonju (Korea, Republic of); Chung, Myung Ja [Department of Pathology, Chonbuk National University Medical School, Jeonju (Korea, Republic of); Yoon, Kwon-Ha [Department of Radiology, Iksan Hospital, Iksan (Korea, Republic of); Kim, So Ri [Department of Internal Medicine and Research Center for Pulmonary Disorders, Chonbuk National University Medical School, Jeonju (Korea, Republic of); Lee, Yong Chul, E-mail: leeyc@jbnu.ac.kr [Department of Internal Medicine and Research Center for Pulmonary Disorders, Chonbuk National University Medical School, Jeonju (Korea, Republic of)

    2012-08-15

    Peroxisome proliferator-activated receptor-{gamma} (PPAR{gamma}) agonists exhibit potent anti-fibrotic effects in the lung and other tissues. Recently, micro-computed tomography (CT) has been a useful tool for the investigation of lung diseases in small animals and is now increasingly applied to visualize and quantify the pulmonary structures. However, there is little information on the assessment for therapeutic effects of PPAR{gamma} agonists on the pulmonary fibrosis in mice using micro-CT. This study was aimed to determine the capability of micro-CT in examining the effects of rosiglitazone on pulmonary fibrosis. We used a murine model of bleomycin-induced lung fibrosis to evaluate the feasibility of micro-CT in evaluating the therapeutic potential of rosiglitazone on pulmonary fibrosis, comparing with pathologic scores. On micro-CT findings, ground glass opacity (80%) and consolidation (20%) were observed predominantly at 3 weeks after the instillation of bleomycin, and the radiologic features became more complex at 6 weeks. In bleomycin-instilled mice treated with rosiglitazone, the majority (80%) showed normal lung features on micro-CT. Radiological-pathologic correlation analyses revealed that ground glass opacity and consolidation were correlated closely with acute inflammation, while reticular opacity was well correlated with histological honeycomb appearance. These results demonstrate that rosiglitazone displays a protective effect on pulmonary fibrosis in mice and that the visualization of bleomycin-induced pulmonary fibrosis using micro-CT is satisfactory to assess the effects of rosiglitazone. It implies that micro-CT can be applied to evaluate therapeutic efficacies of a variety of candidate drugs for lung diseases.

  10. Evaluation of Root Canal Preparation Using Rotary System and Hand Instruments Assessed by Micro-Computed Tomography

    Science.gov (United States)

    Stavileci, Miranda; Hoxha, Veton; Görduysus, Ömer; Tatar, Ilkan; Laperre, Kjell; Hostens, Jeroen; Küçükkaya, Selen; Muhaxheri, Edmond

    2015-01-01

    Background Complete mechanical preparation of the root canal system is rarely achieved. Therefore, the purpose of this study was to evaluate and compare the root canal shaping efficacy of ProTaper rotary files and standard stainless steel K-files using micro-computed tomography. Material/Methods Sixty extracted upper second premolars were selected and divided into 2 groups of 30 teeth each. Before preparation, all samples were scanned by micro-computed tomography. Thirty teeth were prepared with the ProTaper system and the other 30 with stainless steel files. After preparation, the untouched surface and root canal straightening were evaluated with micro-computed tomography. The percentage of untouched root canal surface was calculated in the coronal, middle, and apical parts of the canal. We also calculated straightening of the canal after root canal preparation. Results from the 2 groups were statistically compared using the Minitab statistical package. Results ProTaper rotary files left less untouched root canal surface compared with manual preparation in coronal, middle, and apical sector (protary techniques completely prepared the root canal, and both techniques caused slight straightening of the root canal. PMID:26092929

  11. Evaluation of Root Canal Preparation Using Rotary System and Hand Instruments Assessed by Micro-Computed Tomography.

    Science.gov (United States)

    Stavileci, Miranda; Hoxha, Veton; Görduysus, Ömer; Tatar, Ilkan; Laperre, Kjell; Hostens, Jeroen; Küçükkaya, Selen; Muhaxheri, Edmond

    2015-06-20

    Complete mechanical preparation of the root canal system is rarely achieved. Therefore, the purpose of this study was to evaluate and compare the root canal shaping efficacy of ProTaper rotary files and standard stainless steel K-files using micro-computed tomography. Sixty extracted upper second premolars were selected and divided into 2 groups of 30 teeth each. Before preparation, all samples were scanned by micro-computed tomography. Thirty teeth were prepared with the ProTaper system and the other 30 with stainless steel files. After preparation, the untouched surface and root canal straightening were evaluated with micro-computed tomography. The percentage of untouched root canal surface was calculated in the coronal, middle, and apical parts of the canal. We also calculated straightening of the canal after root canal preparation. Results from the 2 groups were statistically compared using the Minitab statistical package. ProTaper rotary files left less untouched root canal surface compared with manual preparation in coronal, middle, and apical sector (p<0.001). Similarly, there was a statistically significant difference in root canal straightening after preparation between the techniques (p<0.001). Neither manual nor rotary techniques completely prepared the root canal, and both techniques caused slight straightening of the root canal.

  12. Assessing apical transportation in curved canals: comparison between cross-sections and micro-computed tomography

    Directory of Open Access Journals (Sweden)

    Laila Gonzales Freire

    2012-06-01

    Full Text Available The aim of this study was to compare two methods of assessing apical transportation in curved canals after rotary instrumentation, namely, cross-sections and micro-computed tomography (µCT. Thirty mandibular molars were divided into two groups and prepared according to the requirements of each method. In G1 (cross-sections, teeth were embedded in resin blocks and sectioned at 2.0, 3.5, and 5.0 mm from the anatomic apex. Pre- and postoperative sections were photographed and analyzed. In G2 (µCT, teeth were embedded in a rubber-base impression material and scanned before and after instrumentation. Mesiobuccal canals were instrumented with the Twisted File (TF system (SybronEndo, Orange, USA, and mesiolingual canals, with the EndoSequence (ES system (Brasseler, Savannah, USA. Images were reconstructed, and sections corresponding to distances 2.0, 3.5, and 5.0 mm from the anatomic apex were selected for comparison. Data were analyzed using Mann-Whitney's test at a 5% significance level. The TF and ES instruments produced little deviation from the root canal center, with no statistical difference between them (P > 0.05. The canal transportation results were significantly lower (0.056 mm in G2 than in G1 (0.089 mm (p = 0.0012. The µCT method was superior to the cross-section method, especially in view of its ability to preserve specimens and provide results that are more closely related to clinical situations.

  13. Detection of freeze-thaw weathering effect using X-ray micro computed tomography

    Science.gov (United States)

    Park, J.; Hyun, C.; Park, H.

    2011-12-01

    Physical weathering caused by repeated freeze-thaw action of water inside rock pores or cracks was artificially simulated in laboratory. The tests were conducted on three rock types, i.e. diorite, basalt, and tuff, which are the major rock types around King Sejong Station of Korea located in Barton Peninsula, King George Island, Antarctica. The temperature of freeze-thaw cycle was also set with simulated the air temperature of the station, i.e. the maximum temperature was + 10 °C and the minimum temperature was - 20 °C. Three cylindrical specimens composed of one for each rock type with 24.6 mm diameter and 14.5 ~ 17.7 mm length were prepared, and 2 mm diameter and 7 mm shallow depth hole was drilled on the center of the specimens. To exaggerate the effect of the freeze-thaw weathering, all tests were conducted under completely saturated condition. 50 cycles of the freeze-thaw test was carried, and X-ray micro computed tomography (CT) images of each rock specimen were obtained after every 10 cycles. Using X-ray micro CT images, 3D structure was rendered and pore and crack structures were extracted. The changes of porosity, absorption rate and pore and crack structure were detected. Porosity of all specimens was decreased linearly and absorption rate of all specimens was increased linearly as weathering processes; the pore connection and crack propagation was detected in 3D rendering pore and crack structure. The change of tuff specimen is the most remarkable among three rock types used in the research, because of its relatively high initial absorption rate and low strength. This work was supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MEST) (No. 2011-0027520).

  14. Evaluating tooth restorations: micro-computed tomography in practical training for students in dentistry

    Science.gov (United States)

    Deyhle, Hans; Schmidli, Fredy; Krastl, Gabriel; Müller, Bert

    2010-09-01

    Direct composite fillings belong to widespread tooth restoration techniques in dental medicine. The procedure consists of successive steps, which include etching of the prepared tooth surface, bonding and placement of composite in incrementally built up layers. Durability and lifespan of the composite inlays strongly depend on the accurate completion of the individual steps to be also realized by students in dental medicine. Improper handling or nonconformity in the bonding procedure often lead to air enclosures (bubbles) as well as to significant gaps between the composite layers or at the margins of the restoration. Traditionally one analyzes the quality of the restoration cutting the tooth in an arbitrarily selected plane and inspecting this plane by conventional optical microscopy. Although the precision of this established method is satisfactory, it is restricted to the selected two-dimensional plane. Rather simple micro computed tomography (μCT) systems, such as SkyScan 1174™, allows for the non-destructive three-dimensional imaging of restored teeth ex vivo and virtually cutting the tomographic data in any desired direction, offering a powerful tool for inspection of the restored tooth with micrometer resolution before cutting and thus also to select a two-dimensional plane with potential defects. In order to study the influence of the individual steps on the resulted tooth restoration, direct composite fillings were placed in mod cavities of extracted teeth. After etching, an adhesive was applied in half of the specimens. From the tomographic datasets, it becomes clear that gaps occur more frequently when bonding is omitted. The visualization of air enclosures offers to determine the probability to find a micrometer-sized defect using an arbitrarily selected cutting plane for inspection.

  15. Micro-computed tomography of fatigue microdamage in cortical bone using a barium sulfate contrast agent.

    Science.gov (United States)

    Leng, Huijie; Wang, Xiang; Ross, Ryan D; Niebur, Glen L; Roeder, Ryan K

    2008-01-01

    Accumulation of microdamage during fatigue can lead to increased fracture susceptibility in bone. Current techniques for imaging microdamage in bone are inherently destructive and two-dimensional. Therefore, the objective of this study was to image the accumulation of fatigue microdamage in cortical bone using micro-computed tomography (micro-CT) with a barium sulfate (BaSO(4)) contrast agent. Two symmetric notches were machined on the tensile surface of bovine cortical bone beams in order to generate damage ahead of the stress concentrations during four-point bending fatigue. Specimens were loaded to a specified number of cycles or until one notch fractured, such that the other notch exhibited the accumulation of microdamage prior to fracture. Microdamage ahead of the notch was stained in vitro by precipitation of BaSO(4) and imaged using micro-CT. Reconstructed images showed a distinct region of bright voxels around the notch tip or along propagating cracks due to the presence of BaSO(4), which was verified by backscattered electron imaging and energy dispersive spectroscopy. The shape of the stained region ahead of the notch tip was consistent with principal strain contours calculated by finite element analysis. The relative volume of the stained region was correlated with the number of loading cycles by non-linear regression using a power-law. This study demonstrates new methods for the non-destructive and three-dimensional detection of fatigue microdamage accumulation in cortical bone in vitro, which may be useful to gain further understanding into the role of microdamage in bone fragility.

  16. Effects of lithium on extraction socket healing in rats assessed with micro-computed tomography.

    Science.gov (United States)

    Zeng, Yun Ting; Fu, Bin; Tang, Guo Hua; Zhang, Lei; Qian, Yu Fen

    2013-09-01

    Lithium is an activator of β-catenin signaling and β-catenin plays an important role in regulating bone formation and remodeling. The purpose of this study was to investigate the effects of lithium on bone repair in tooth extraction sockets in rats. Twenty male Wistar rats were subjected to maxillary left second molar extraction. The animals received a daily injection of lithium chloride (LiCl) or the same dose of sodium chloride (NaCl) starting 7 days before tooth extraction until sacrifice 14 days after extraction. Rats were randomly divided into: (1) a pre-treated group that received LiCl injection from 7 days before to 3 days after tooth extraction; (2) a post-treated group that received LiCl injection starting 4 days after tooth extraction; (3) a continuously treated group that received LiCl injection for the entire 21 days; and (4) a control group that received NaCl injection only. The volume of new bone and the bone density in the extraction socket were quantified by micro-computed tomography. The percentage of new bone formation in the extraction socket was as follows: 63.2 ± 13.4% (pre-treated group), 53.9 ± 9.8% (post-treated), 23.8 ± 8.0% (continuously treated) and 37.5 ± 4.2% (control). The difference in percentage was statistically significant between each pair of groups. Pre- and post-treated groups also showed a significant increase in the density of new bone. Lithium enhances bone repair in extraction sockets when delivered before or after tooth extraction. Tooth extraction during lithium treatment may impair bone healing.

  17. Attenuation Drift in the Micro-Computed Tomography System at LLNL

    Energy Technology Data Exchange (ETDEWEB)

    Dooraghi, Alex A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Brown, William [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Seetho, Isaac [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kallman, Jeff [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Lennox, Kristin [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Glascoe, Lee [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-01-12

    The maximum allowable level of drift in the linear attenuation coefficients (μ) for a Lawrence Livermore National Laboratory (LLNL) micro-computed tomography (MCT) system was determined to be 0.1%. After ~100 scans were acquired during the period of November 2014 to March 2015, the drift in μ for a set of six reference materials reached or exceeded 0.1%. Two strategies have been identified to account for or correct the drift. First, normalizing the 160 kV and 100 kV μ data by the μ of water at the corresponding energy, in contrast to conducting normalization at the 160 kV energy only, significantly compensates for measurement drift. Even after the modified normalization, μ of polytetrafluoroethylene (PTFE) increases linearly with scan number at an average rate of 0.00147% per scan. This is consistent with PTFE radiation damage documented in the literature. The second strategy suggested is the replacement of the PTFE reference with fluorinated ethylene propylene (FEP), which has the same effective atomic number (Ze) and electron density (ρe) as PTFE, but is 10 times more radiation resistant. This is important as effective atomic number and electron density are key parameters in analysis. The presence of a material with properties such as PTFE, when taken together with the remaining references, allows for a broad range of the (Ze, ρe) feature space to be used in analysis. While FEP is documented as 10 times more radiation resistant, testing will be necessary to assess how often, if necessary, FEP will need to be replaced. As radiation damage to references has been observed, it will be necessary to monitor all reference materials for radiation damage to ensure consistent x-ray characteristics of the references.

  18. Dual-Energy Micro-Computed Tomography Imaging of Radiation-Induced Vascular Changes in Primary Mouse Sarcomas

    International Nuclear Information System (INIS)

    Moding, Everett J.; Clark, Darin P.; Qi, Yi; Li, Yifan; Ma, Yan; Ghaghada, Ketan; Johnson, G. Allan; Kirsch, David G.; Badea, Cristian T.

    2013-01-01

    Purpose: To evaluate the effects of radiation therapy on primary tumor vasculature using dual-energy (DE) micro-computed tomography (micro-CT). Methods and Materials: Primary sarcomas were generated with mutant Kras and p53. Unirradiated tumors were compared with tumors irradiated with 20 Gy. A liposomal-iodinated contrast agent was administered 1 day after treatment, and mice were imaged immediately after injection (day 1) and 3 days later (day 4) with DE micro-CT. CT-derived tumor sizes were used to assess tumor growth. After DE decomposition, iodine maps were used to assess tumor fractional blood volume (FBV) at day 1 and tumor vascular permeability at day 4. For comparison, tumor vascularity and vascular permeability were also evaluated histologically by use of CD31 immunofluorescence and fluorescently-labeled dextrans. Results: Radiation treatment significantly decreased tumor growth from day 1 to day 4 (P 2 =0.53) and dextran accumulation (R 2 =0.63) on day 4, respectively. Despite no change in MVD measured by histology, tumor FBV significantly increased after irradiation as measured by DE micro-CT (0.070 vs 0.091, P<.05). Both dextran and liposomal-iodine accumulation in tumors increased significantly after irradiation, with dextran fractional area increasing 5.2-fold and liposomal-iodine concentration increasing 4.0-fold. Conclusions: DE micro-CT is an effective tool for noninvasive assessment of vascular changes in primary tumors. Tumor blood volume and vascular permeability increased after a single therapeutic dose of radiation treatment

  19. Dual-Energy Micro-Computed Tomography Imaging of Radiation-Induced Vascular Changes in Primary Mouse Sarcomas

    Energy Technology Data Exchange (ETDEWEB)

    Moding, Everett J. [Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina (United States); Clark, Darin P.; Qi, Yi [Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina (United States); Li, Yifan; Ma, Yan [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Ghaghada, Ketan [The Edward B. Singleton Department of Pediatric Radiology, Texas Children' s Hospital, Houston, Texas (United States); Johnson, G. Allan [Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina (United States); Kirsch, David G. [Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina (United States); Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Badea, Cristian T., E-mail: cristian.badea@duke.edu [Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina (United States)

    2013-04-01

    Purpose: To evaluate the effects of radiation therapy on primary tumor vasculature using dual-energy (DE) micro-computed tomography (micro-CT). Methods and Materials: Primary sarcomas were generated with mutant Kras and p53. Unirradiated tumors were compared with tumors irradiated with 20 Gy. A liposomal-iodinated contrast agent was administered 1 day after treatment, and mice were imaged immediately after injection (day 1) and 3 days later (day 4) with DE micro-CT. CT-derived tumor sizes were used to assess tumor growth. After DE decomposition, iodine maps were used to assess tumor fractional blood volume (FBV) at day 1 and tumor vascular permeability at day 4. For comparison, tumor vascularity and vascular permeability were also evaluated histologically by use of CD31 immunofluorescence and fluorescently-labeled dextrans. Results: Radiation treatment significantly decreased tumor growth from day 1 to day 4 (P<.05). There was a positive correlation between CT measurement of tumor FBV on day 1 and extravasated iodine on day 4 with microvascular density (MVD) on day 4 (R{sup 2}=0.53) and dextran accumulation (R{sup 2}=0.63) on day 4, respectively. Despite no change in MVD measured by histology, tumor FBV significantly increased after irradiation as measured by DE micro-CT (0.070 vs 0.091, P<.05). Both dextran and liposomal-iodine accumulation in tumors increased significantly after irradiation, with dextran fractional area increasing 5.2-fold and liposomal-iodine concentration increasing 4.0-fold. Conclusions: DE micro-CT is an effective tool for noninvasive assessment of vascular changes in primary tumors. Tumor blood volume and vascular permeability increased after a single therapeutic dose of radiation treatment.

  20. Micro-computed tomography study of the internal anatomy of mesial root canals of mandibular molars.

    Science.gov (United States)

    Villas-Bôas, Marcelo Haas; Bernardineli, Norberti; Cavenago, Bruno Cavalini; Marciano, Marina; Del Carpio-Perochena, Aldo; de Moraes, Ivaldo Gomes; Duarte, Marco H; Bramante, Clovis M; Ordinola-Zapata, Ronald

    2011-12-01

    The aim of this study was to determine the mesiodistal and buccolingual diameter, apical volume, and the presence of isthmuses at the apical level of mesial root canals of mandibular molars. Sixty extracted first and second mandibular molars were scanned by using a SkyScan 1076 micro-computed tomography system with a voxel size of 18 μm. The apical thirds of the samples were reconstructed to allow a perpendicular section of the apical third by using the multiplanar reconstruction tool of the OsiriX software. The mesiodistal and the buccolingual distances of root canals were measured between the 1- to 4-mm levels. The type of root canal isthmuses present at these levels was classified by using modified criteria of Hsu and Kim. The volume of the root canal anatomy between the 1- to 3-mm apical levels was obtained by using the CTAN-CTVOL software. The medians of the mesiodistal diameter at the 1-, 2-, 3-, and 4-mm levels in the mesiobuccal and mesiolingual canals were 0.22 and 0.23 mm, 0.27 and 0.27 mm, 0.30 and 0.30 mm, and 0.36 and 0.35 mm, respectively. The buccolingual lengths at the 1-, 2-, 3-, and 4-mm levels were 0.37-0.35 mm, 0.55-0.41 mm, 0.54-0.49 mm, and 0.54 and 0.60 mm, respectively. The presence of isthmuses was more prevalent at the 3- to 4-mm level. However, 27 cases presented complete or incomplete isthmuses at the 1-mm apical level. The mean of the volume of the apical third was 0.83 mm(3), with a minimum value of 0.02 and a maximum value of 2.4 mm(3). Mesial root canals of mandibular molars do not present a consistent pattern. A high variability of apical diameters exists. The presence of isthmuses at the apical third was not uncommon even at the 1-mm apical level. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  1. Attenuating trabecular morphology associated with low magnesium diet evaluated using micro computed tomography.

    Directory of Open Access Journals (Sweden)

    Shu-Ju Tu

    Full Text Available The literature shows that bone mineral density (BMD and the geometric architecture of trabecular bone in the femur may be affected by inadequate dietary intake of Mg. In this study, we used microcomputed tomography (micro-CT to characterize and quantify the impact of a low-Mg diet on femoral trabecular bones in mice.Four-week-old C57BL/6J male mice were randomly assigned to 2 groups and supplied either a normal or low-Mg diet for 8weeks. Samples of plasma and urine were collected for biochemical analysis, and femur tissues were removed for micro-CT imaging. In addition to considering standard parameters, we regarded trabecular bone as a cylindrical rod and used computational algorithms for a technical assessment of the morphological characteristics of the bones. BMD (mg-HA/cm3 was obtained using a standard phantom.We observed a decline in the total tissue volume, bone volume, percent bone volume, fractal dimension, number of trabecular segments, number of connecting nodes, bone mineral content (mg-HA, and BMD, as well as an increase in the structural model index and surface-area-to-volume ratio in low-Mg mice. Subsequently, we examined the distributions of the trabecular segment length and radius, and a series of specific local maximums were identified. The biochemical analysis revealed a 43% (96% decrease in Mg and a 40% (71% decrease in Ca in plasma (urine excretion.This technical assessment performed using micro-CT revealed a lower population of femoral trabecular bones and a decrease in BMD at the distal metaphysis in the low-Mg mice. Examining the distributions of the length and radius of trabecular segments showed that the average length and radius of the trabecular segments in low-Mg mice are similar to those in normal mice.

  2. High pressure-elevated temperature x-ray micro-computed tomography for subsurface applications.

    Science.gov (United States)

    Iglauer, Stefan; Lebedev, Maxim

    2018-06-01

    Physical, chemical and mechanical pore-scale (i.e. micrometer-scale) mechanisms in rock are of key importance in many, if not all, subsurface processes. These processes are highly relevant in various applications, e.g. hydrocarbon recovery, CO 2 geo-sequestration, geophysical exploration, water production, geothermal energy production, or the prediction of the location of valuable hydrothermal deposits. Typical examples are multi-phase flow (e.g. oil and water) displacements driven by buoyancy, viscous or capillary forces, mineral-fluid interactions (e.g. mineral dissolution and/or precipitation over geological times), geo-mechanical rock behaviour (e.g. rock compaction during diagenesis) or fines migration during water production, which can dramatically reduce reservoir permeability (and thus reservoir performance). All above examples are 3D processes, and 2D experiments (as traditionally done for micro-scale investigations) will thus only provide qualitative information; for instance the percolation threshold is much lower in 3D than in 2D. However, with the advent of x-ray micro-computed tomography (μCT) - which is now routinely used - this limitation has been overcome, and such pore-scale processes can be observed in 3D at micrometer-scale. A serious complication is, however, the fact that in the subsurface high pressures and elevated temperatures (HPET) prevail, due to the hydrostatic and geothermal gradients imposed upon it. Such HPET-reservoir conditions significantly change the above mentioned physical and chemical processes, e.g. gas density is much higher at high pressure, which strongly affects buoyancy and wettability and thus gas distributions in the subsurface; or chemical reactions are significantly accelerated at increased temperature, strongly affecting fluid-rock interactions and thus diagenesis and deposition of valuable minerals. It is thus necessary to apply HPET conditions to the aforementioned μCT experiments, to be able to mimic subsurface

  3. X-ray micro computed tomography characterization of cellular SiC foams for their applications in chemical engineering

    Energy Technology Data Exchange (ETDEWEB)

    Ou, Xiaoxia [School of Chemical Engineering and Analytical Science, The University of Manchester, M13 9PL (United Kingdom); Zhang, Xun; Lowe, Tristan [Henry Moseley X-ray Imaging Facility, Materials Science Centre, School of Materials, The University of Manchester, M13 9PL (United Kingdom); Blanc, Remi [FEI, 3 Impasse Rudolf Diesel, BP 50227, 33708 Mérignac (France); Rad, Mansoureh Norouzi [School of Chemical Engineering and Analytical Science, The University of Manchester, M13 9PL (United Kingdom); Wang, Ying [Henry Moseley X-ray Imaging Facility, Materials Science Centre, School of Materials, The University of Manchester, M13 9PL (United Kingdom); Batail, Nelly; Pham, Charlotte [SICAT SARL, 20 Place des Halles, 67000 Strasbourg (France); Shokri, Nima; Garforth, Arthur A. [School of Chemical Engineering and Analytical Science, The University of Manchester, M13 9PL (United Kingdom); Withers, Philip J. [Henry Moseley X-ray Imaging Facility, Materials Science Centre, School of Materials, The University of Manchester, M13 9PL (United Kingdom); Fan, Xiaolei, E-mail: xiaolei.fan@manchester.ac.uk [School of Chemical Engineering and Analytical Science, The University of Manchester, M13 9PL (United Kingdom)

    2017-01-15

    Open-cell SiC foams clearly are promising materials for continuous-flow chemical applications such as heterogeneous catalysis and distillation. X-ray micro computed tomography characterization of cellular β-SiC foams at a spatial voxel size of 13.6{sup 3} μm{sup 3} and the interpretation of morphological properties of SiC open-cell foams with implications to their transport properties are presented. Static liquid hold-up in SiC foams was investigated through in-situ draining experiments for the first time using the μ-CT technique providing thorough 3D information about the amount and distribution of liquid hold-up inside the foam. This will enable better modeling and design of structured reactors based on SiC foams in the future. In order to see more practical uses, μ-CT data of cellular foams must be exploited to optimize the design of the morphology of foams for a specific application. - Highlights: •Characterization of SiC foams using novel X-ray micro computed tomography. •Interpretation of structural properties of SiC foams regarding to their transport properties. •Static liquid hold-up analysis of SiC foams through in-situ draining experiments.

  4. Non-destructive morphological observations of the fleshy brittle star, Asteronyx loveni using micro-computed tomography (Echinodermata, Ophiuroidea, Euryalida).

    Science.gov (United States)

    Okanishi, Masanori; Fujita, Toshihiko; Maekawa, Yu; Sasaki, Takenori

    2017-01-01

    The first morphological observation of a euryalid brittle star, Asteronyx loveni , using non-destructive X-ray micro-computed tomography (µCT) was performed. The body of euryalids is covered by thick skin, and it is very difficult to observe the ossicles without dissolving the skin. Computed tomography with micrometer resolution (approximately 4.5-15.4 µm) was used to construct 3D images of skeletal ossicles and soft tissues in the ophiuroid's body. Shape and positional arrangement of taxonomically important ossicles were clearly observed without any damage to the body. Detailed pathways inside the vertebral ossicles, lateral arm plates, and arm spines for passage of nerves and water vascular structures were observed. Inter-vertebral muscles were also observed. Forms and 3D arrangements of many important taxonomical characters of the euryalids were scrutinized by µCT in high enough resolution for taxonomic description of ophiuroids.

  5. Non-destructive morphological observations of the fleshy brittle star, Asteronyx loveni using micro-computed tomography (Echinodermata, Ophiuroidea, Euryalida

    Directory of Open Access Journals (Sweden)

    Massanori Okanishi

    2017-03-01

    Full Text Available The first morphological observation of a euryalid brittle star, Asteronyx loveni, using non-destructive X-ray micro-computed tomography (µCT was performed. The body of euryalids is covered by thick skin, and it is very difficult to observe the ossicles without dissolving the skin. Computed tomography with micrometer resolution (approximately 4.5–15.4 µm was used to construct 3D images of skeletal ossicles and soft tissues in the ophiuroid’s body. Shape and positional arrangement of taxonomically important ossicles were clearly observed without any damage to the body. Detailed pathways inside the vertebral ossicles, lateral arm plates, and arm spines for passage of nerves and water vascular structures were observed. Inter-vertebral muscles were also observed. Forms and 3D arrangements of many important taxonomical characters of the euryalids were scrutinized by µCT in high enough resolution for taxonomic description of ophiuroids.

  6. Micro-computed tomography-based phenotypic approaches in embryology: procedural artifacts on assessments of embryonic craniofacial growth and development

    Directory of Open Access Journals (Sweden)

    Logan C Cairine

    2010-02-01

    Full Text Available Abstract Background Growing demand for three dimensional (3D digital images of embryos for purposes of phenotypic assessment drives implementation of new histological and imaging techniques. Among these micro-computed tomography (μCT has recently been utilized as an effective and practical method for generating images at resolutions permitting 3D quantitative analysis of gross morphological attributes of developing tissues and organs in embryonic mice. However, histological processing in preparation for μCT scanning induces changes in organ size and shape. Establishing normative expectations for experimentally induced changes in size and shape will be an important feature of 3D μCT-based phenotypic assessments, especially if quantifying differences in the values of those parameters between comparison sets of developing embryos is a primary aim. Toward that end, we assessed the nature and degree of morphological artifacts attending μCT scanning following use of common fixatives, using a two dimensional (2D landmark geometric morphometric approach to track the accumulation of distortions affecting the embryonic head from the native, uterine state through to fixation and subsequent scanning. Results Bouin's fixation reduced average centroid sizes of embryonic mouse crania by approximately 30% and substantially altered the morphometric shape, as measured by the shift in Procrustes distance, from the unfixed state, after the data were normalized for naturally occurring shape variation. Subsequent μCT scanning produced negligible changes in size but did appear to reduce or even reverse fixation-induced random shape changes. Mixtures of paraformaldehyde + glutaraldehyde reduced average centroid sizes by 2-3%. Changes in craniofacial shape progressively increased post-fixation. Conclusions The degree to which artifacts are introduced in the generation of random craniofacial shape variation relates to the degree of specimen dehydration during the

  7. Micro-computed tomography-based phenotypic approaches in embryology: procedural artifacts on assessments of embryonic craniofacial growth and development.

    Science.gov (United States)

    Schmidt, Eric J; Parsons, Trish E; Jamniczky, Heather A; Gitelman, Julian; Trpkov, Cvett; Boughner, Julia C; Logan, C Cairine; Sensen, Christoph W; Hallgrímsson, Benedikt

    2010-02-17

    Growing demand for three dimensional (3D) digital images of embryos for purposes of phenotypic assessment drives implementation of new histological and imaging techniques. Among these micro-computed tomography (microCT) has recently been utilized as an effective and practical method for generating images at resolutions permitting 3D quantitative analysis of gross morphological attributes of developing tissues and organs in embryonic mice. However, histological processing in preparation for microCT scanning induces changes in organ size and shape. Establishing normative expectations for experimentally induced changes in size and shape will be an important feature of 3D microCT-based phenotypic assessments, especially if quantifying differences in the values of those parameters between comparison sets of developing embryos is a primary aim. Toward that end, we assessed the nature and degree of morphological artifacts attending microCT scanning following use of common fixatives, using a two dimensional (2D) landmark geometric morphometric approach to track the accumulation of distortions affecting the embryonic head from the native, uterine state through to fixation and subsequent scanning. Bouin's fixation reduced average centroid sizes of embryonic mouse crania by approximately 30% and substantially altered the morphometric shape, as measured by the shift in Procrustes distance, from the unfixed state, after the data were normalized for naturally occurring shape variation. Subsequent microCT scanning produced negligible changes in size but did appear to reduce or even reverse fixation-induced random shape changes. Mixtures of paraformaldehyde + glutaraldehyde reduced average centroid sizes by 2-3%. Changes in craniofacial shape progressively increased post-fixation. The degree to which artifacts are introduced in the generation of random craniofacial shape variation relates to the degree of specimen dehydration during the initial fixation. Fixation methods that

  8. A Micro-Computed Tomography Technique to Study the Quality of Fibre Optics Embedded in Composite Materials

    Directory of Open Access Journals (Sweden)

    Gabriele Chiesura

    2015-05-01

    Full Text Available Quality of embedment of optical fibre sensors in carbon fibre-reinforced polymers plays an important role in the resultant properties of the composite, as well as for the correct monitoring of the structure. Therefore, availability of a tool able to check the optical fibre sensor-composite interaction becomes essential. High-resolution 3D X-ray Micro-Computed Tomography, or Micro-CT, is a relatively new non-destructive inspection technique which enables investigations of the internal structure of a sample without actually compromising its integrity. In this work the feasibility of inspecting the position, the orientation and, more generally, the quality of the embedment of an optical fibre sensor in a carbon fibre reinforced laminate at unit cell level have been proven.

  9. Physical characterization and performance evaluation of an x-ray micro-computed tomography system for dimensional metrology applications

    DEFF Research Database (Denmark)

    Hiller, Jochen; Maisl, Michael; Reindl, Leonard M

    2012-01-01

    This paper presents physical and metrological characterization measurements conducted for an industrial x-ray micro-computed tomography (CT) system. As is well known in CT metrology, many factors, e.g., in the scanning and reconstruction process, the image processing, and the 3D data evaluation...... components of a CT scanner, i.e. the x-ray tube and the flat-panel detector, are characterized. The contrast and noise transfer property of the scanner is obtained using image-processing methods based on linear systems theory. A long-term temperature measurement in the scanner cabinet has been carried out....... The dimensional measurement property has been quantified by using a calibrated ball-bar and uncertainty budgeting. Information about the performance of a CT scanner system in terms of contrast and noise transmission and sources of geometrical errors will help plan CT scans more efficiently. In particular...

  10. Volumetric quantification of bone-implant contact using micro-computed tomography analysis based on region-based segmentation.

    Science.gov (United States)

    Kang, Sung-Won; Lee, Woo-Jin; Choi, Soon-Chul; Lee, Sam-Sun; Heo, Min-Suk; Huh, Kyung-Hoe; Kim, Tae-Il; Yi, Won-Jin

    2015-03-01

    We have developed a new method of segmenting the areas of absorbable implants and bone using region-based segmentation of micro-computed tomography (micro-CT) images, which allowed us to quantify volumetric bone-implant contact (VBIC) and volumetric absorption (VA). The simple threshold technique generally used in micro-CT analysis cannot be used to segment the areas of absorbable implants and bone. Instead, a region-based segmentation method, a region-labeling method, and subsequent morphological operations were successively applied to micro-CT images. The three-dimensional VBIC and VA of the absorbable implant were then calculated over the entire volume of the implant. Two-dimensional (2D) bone-implant contact (BIC) and bone area (BA) were also measured based on the conventional histomorphometric method. VA and VBIC increased significantly with as the healing period increased (pimplants using micro-CT analysis using a region-based segmentation method.

  11. Micro computed tomography (CT) scanned anatomical gateway to insect pest bioinformatics

    Science.gov (United States)

    An international collaboration to establish an interactive Digital Video Library for a Systems Biology Approach to study the Asian citrus Psyllid and psyllid genomics/proteomics interactions is demonstrated. Advances in micro-CT, digital computed tomography (CT) scan uses X-rays to make detailed pic...

  12. Automatic quantitative micro-computed tomography evaluation of angiogenesis in an axially vascularized tissue-engineered bone construct.

    Science.gov (United States)

    Arkudas, Andreas; Beier, Justus Patrick; Pryymachuk, Galyna; Hoereth, Tobias; Bleiziffer, Oliver; Polykandriotis, Elias; Hess, Andreas; Gulle, Heinz; Horch, Raymund E; Kneser, Ulrich

    2010-12-01

    We invented an automatic observer-independent quantitative method to analyze vascularization using micro-computed tomography (CT) along with three-dimensional (3D) reconstruction in a tissue engineering model. An arteriovenous loop was created in the medial thigh of 30 rats and was placed in a particulated porous hydroxyapatite and beta-tricalcium phosphate matrix, filled with fibrin (10 mg/mL fibrinogen and 2 IU/mL thrombin) without (group A) or with (group B) application of fibrin-gel-immobilized angiogenetic growth factors vascular endothelial growth factor (VEGF¹⁶⁵) and basic fibroblast growth factor (bFGF). The explantation intervals were 2, 4, and 8 weeks. Specimens were investigated by means of micro-CT followed by an automatic 3D analysis, which was correlated to histomorphometrical findings. In both groups, the arteriovenous loop led to generation of dense vascularized connective tissue with differentiated and functional vessels inside the matrix. Quantitative analysis of vascularization using micro-CT showed to be superior to histological analysis. The micro-CT analysis also allows the assessment of different other, more complex vascularization parameters within 3D constructs, demonstrating an early improvement of vascularization by application of fibrin-gel-immobilized VEGF¹⁶⁵ and bFGF. In this study quantitative analysis of vascularization using micro-CT along with 3D reconstruction and automatic analysis exhibit to be a powerful method superior to histological evaluation of cross sections.

  13. Synchrotron-radiation-based X-ray micro-computed tomography reveals dental bur debris under dental composite restorations.

    Science.gov (United States)

    Hedayat, Assem; Nagy, Nicole; Packota, Garnet; Monteith, Judy; Allen, Darcy; Wysokinski, Tomasz; Zhu, Ning

    2016-05-01

    Dental burs are used extensively in dentistry to mechanically prepare tooth structures for restorations (fillings), yet little has been reported on the bur debris left behind in the teeth, and whether it poses potential health risks to patients. Here it is aimed to image dental bur debris under dental fillings, and allude to the potential health hazards that can be caused by this debris when left in direct contact with the biological surroundings, specifically when the debris is made of a non-biocompatible material. Non-destructive micro-computed tomography using the BioMedical Imaging & Therapy facility 05ID-2 beamline at the Canadian Light Source was pursued at 50 keV and at a pixel size of 4 µm to image dental bur fragments under a composite resin dental filling. The bur's cutting edges that produced the fragment were also chemically analyzed. The technique revealed dental bur fragments of different sizes in different locations on the floor of the prepared surface of the teeth and under the filling, which places them in direct contact with the dentinal tubules and the dentinal fluid circulating within them. Dispersive X-ray spectroscopy elemental analysis of the dental bur edges revealed that the fragments are made of tungsten carbide-cobalt, which is bio-incompatible.

  14. Micro computed tomography evaluation of the Self-adjusting file and ProTaper Universal system on curved mandibular molars.

    Science.gov (United States)

    Serefoglu, Burcu; Piskin, Beyser

    2017-09-26

    The aim of this investigation was to compare the cleaning and shaping efficiency of Self-adjusting file and Protaper, and to assess the correlation between root canal curvature and working time in mandibular molars using micro-computed tomography. Twenty extracted mandibular molars instrumented with Protaper and Self-adjusting file and the total working time was measured in mesial canals. The changes in canal volume, surface area and structure model index, transportation, uninstrumented area and the correlation between working-time and the curvature were analyzed. Although no statistically significant difference was observed between two systems in distal canals (p>0.05), a significantly higher amount of removed dentin volume and lower uninstrumented area were provided by Protaper in mesial canals (p<0.0001). A correlation between working-time and the canal-curvature was also observed in mesial canals for both groups (SAFr 2 =0.792, p<0.0004, PTUr 2 =0.9098, p<0.0001).

  15. Quantitative three-dimensional analysis of root canal curvature in maxillary first molars using micro-computed tomography.

    Science.gov (United States)

    Lee, Jong-Ki; Ha, Byung-Hyun; Choi, Jeong-Ho; Heo, Seok-Mo; Perinpanayagam, Hiran

    2006-10-01

    In endodontic therapy, access and instrumentation are strongly affected by root canal curvature. However, the few studies that have actually measured curvature are mostly from two-dimensional radiographs. The purpose of this study was to measure the three-dimensional (3D) canal curvature in maxillary first molars using micro-computed tomography (microCT) and mathematical modeling. Extracted maxillary first molars (46) were scanned by microCT (502 image slices/tooth, 1024 X 1024 pixels, voxel size of 19.5 x 19.5 x 39.0 microm) and their canals reconstructed by 3D modeling software. The intersection of major and minor axes in the canal space of each image slice were connected to create an imaginary central axis for each canal. The radius of curvature of the tangential circle was measured and inverted as a measure of curvature using custom-made mathematical modeling software. Root canal curvature was greatest in the apical third and least in the middle third for all canals. The greatest curvatures were in the mesiobuccal (MB) canal (0.76 +/- 0.48 mm(-1)) with abrupt curves, and the least curvatures were in the palatal (P) canal (0.38 +/- 0.34 mm(-1)) with a gradual curve. This study has measured the 3D curvature of root canals in maxillary first molars and reinforced the value of microCT with mathematical modeling.

  16. Using Micro-Computed Tomography to Evaluate the Dynamics of Orthodontically Induced Root Resorption Repair in a Rat Model.

    Directory of Open Access Journals (Sweden)

    Xiaolin Xu

    Full Text Available To observe dynamic changes in root resorption repair, tooth movement relapse and alveolar bone microstructure following the application of orthodontic force.Forces of 20 g, 50 g or 100 g were delivered to the left maxillary first molars of fifteen 10-week-old rats for 14 days. Each rat was subjected to micro-computed tomography scanning at 0, 3, 7, 10, 14, 28 and 42 days after force removal. The root resorption crater volume, tooth movement relapse and alveolar bone microarchitecture were measured at each time point.From day 3 to day 14, the root resorption volume decreased significantly in each group. In the 20-g force group, the root resorption volume gradually stabilized after 14 days, whereas in the 50-g and 100-g force groups, it stabilized after 28 days. In all groups, tooth movement relapsed significantly from day 0 to day 14 and then remained stable. From day 3 to day 10, the 20-g group exhibited faster relapse than the 50-g and 100-g groups. In all groups, the structure model index and trabecular separation decreased slowly from day 0 to day 10 and eventually stabilized. Trabecular number increased slowly from day 0 to day 7 and then stabilized.The initial stage of root resorption repair did not change significantly and was followed by a dramatic repair period before stabilizing. The most serious tooth movement relapse occurred immediately after the appliance was removed, and then the tooth completely returned to the original position.

  17. Micro-Computed Tomography Detection of Gold Nanoparticle-Labelled Mesenchymal Stem Cells in the Rat Subretinal Layer.

    Science.gov (United States)

    Mok, Pooi Ling; Leow, Sue Ngein; Koh, Avin Ee-Hwan; Mohd Nizam, Hairul Harun; Ding, Suet Lee Shirley; Luu, Chi; Ruhaslizan, Raduan; Wong, Hon Seng; Halim, Wan Haslina Wan Abdul; Ng, Min Hwei; Idrus, Ruszymah Binti Hj; Chowdhury, Shiplu Roy; Bastion, Catherine Mae-Lynn; Subbiah, Suresh Kumar; Higuchi, Akon; Alarfaj, Abdullah A; Then, Kong Yong

    2017-02-08

    Mesenchymal stem cells are widely used in many pre-clinical and clinical settings. Despite advances in molecular technology; the migration and homing activities of these cells in in vivo systems are not well understood. Labelling mesenchymal stem cells with gold nanoparticles has no cytotoxic effect and may offer suitable indications for stem cell tracking. Here, we report a simple protocol to label mesenchymal stem cells using 80 nm gold nanoparticles. Once the cells and particles were incubated together for 24 h, the labelled products were injected into the rat subretinal layer. Micro-computed tomography was then conducted on the 15th and 30th day post-injection to track the movement of these cells, as visualized by an area of hyperdensity from the coronal section images of the rat head. In addition, we confirmed the cellular uptake of the gold nanoparticles by the mesenchymal stem cells using transmission electron microscopy. As opposed to other methods, the current protocol provides a simple, less labour-intensive and more efficient labelling mechanism for real-time cell tracking. Finally, we discuss the potential manipulations of gold nanoparticles in stem cells for cell replacement and cancer therapy in ocular disorders or diseases.

  18. Use of micro computed-tomography and 3D printing for reverse engineering of mouse embryo nasal capsule

    International Nuclear Information System (INIS)

    Tesařová, M.; Zikmund, T.; Kaiser, J.; Kaucká, M.; Adameyko, I.; Jaroš, J.; Paloušek, D.; Škaroupka, D.

    2016-01-01

    Imaging of increasingly complex cartilage in vertebrate embryos is one of the key tasks of developmental biology. This is especially important to study shape-organizing processes during initial skeletal formation and growth. Advanced imaging techniques that are reflecting biological needs give a powerful impulse to push the boundaries of biological visualization. Recently, techniques for contrasting tissues and organs have improved considerably, extending traditional 2D imaging approaches to 3D . X-ray micro computed tomography (μCT), which allows 3D imaging of biological objects including their internal structures with a resolution in the micrometer range, in combination with contrasting techniques seems to be the most suitable approach for non-destructive imaging of embryonic developing cartilage. Despite there are many software-based ways for visualization of 3D data sets, having a real solid model of the studied object might give novel opportunities to fully understand the shape-organizing processes in the developing body. In this feasibility study we demonstrated the full procedure of creating a real 3D object of mouse embryo nasal capsule, i.e. the staining, the μCT scanning combined by the advanced data processing and the 3D printing

  19. Virtual forensic entomology: improving estimates of minimum post-mortem interval with 3D micro-computed tomography.

    Science.gov (United States)

    Richards, Cameron S; Simonsen, Thomas J; Abel, Richard L; Hall, Martin J R; Schwyn, Daniel A; Wicklein, Martina

    2012-07-10

    We demonstrate how micro-computed tomography (micro-CT) can be a powerful tool for describing internal and external morphological changes in Calliphora vicina (Diptera: Calliphoridae) during metamorphosis. Pupae were sampled during the 1st, 2nd, 3rd and 4th quarter of development after the onset of pupariation at 23 °C, and placed directly into 80% ethanol for preservation. In order to find the optimal contrast, four batches of pupae were treated differently: batch one was stained in 0.5M aqueous iodine for 1 day; two for 7 days; three was tagged with a radiopaque dye; four was left unstained (control). Pupae stained for 7d in iodine resulted in the best contrast micro-CT scans. The scans were of sufficiently high spatial resolution (17.2 μm) to visualise the internal morphology of developing pharate adults at all four ages. A combination of external and internal morphological characters was shown to have the potential to estimate the age of blowfly pupae with a higher degree of accuracy and precision than using external morphological characters alone. Age specific developmental characters are described. The technique could be used as a measure to estimate a minimum post-mortem interval in cases of suspicious death where pupae are the oldest stages of insect evidence collected. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  20. Micro-Computed Tomography Detection of Gold Nanoparticle-Labelled Mesenchymal Stem Cells in the Rat Subretinal Layer

    Directory of Open Access Journals (Sweden)

    Pooi Ling Mok

    2017-02-01

    Full Text Available Mesenchymal stem cells are widely used in many pre-clinical and clinical settings. Despite advances in molecular technology; the migration and homing activities of these cells in in vivo systems are not well understood. Labelling mesenchymal stem cells with gold nanoparticles has no cytotoxic effect and may offer suitable indications for stem cell tracking. Here, we report a simple protocol to label mesenchymal stem cells using 80 nm gold nanoparticles. Once the cells and particles were incubated together for 24 h, the labelled products were injected into the rat subretinal layer. Micro-computed tomography was then conducted on the 15th and 30th day post-injection to track the movement of these cells, as visualized by an area of hyperdensity from the coronal section images of the rat head. In addition, we confirmed the cellular uptake of the gold nanoparticles by the mesenchymal stem cells using transmission electron microscopy. As opposed to other methods, the current protocol provides a simple, less labour-intensive and more efficient labelling mechanism for real-time cell tracking. Finally, we discuss the potential manipulations of gold nanoparticles in stem cells for cell replacement and cancer therapy in ocular disorders or diseases.

  1. Application of X-ray micro-computed tomography on high-speed cavitating diesel fuel flows

    Energy Technology Data Exchange (ETDEWEB)

    Mitroglou, N.; Lorenzi, M.; Gavaises, M. [City University London, School of Mathematics Computer Science and Engineering, London (United Kingdom); Santini, M. [University of Bergamo, Department of Engineering, Bergamo (Italy)

    2016-11-15

    The flow inside a purpose built enlarged single-orifice nozzle replica is quantified using time-averaged X-ray micro-computed tomography (micro-CT) and high-speed shadowgraphy. Results have been obtained at Reynolds and cavitation numbers similar to those of real-size injectors. Good agreement for the cavitation extent inside the orifice is found between the micro-CT and the corresponding temporal mean 2D cavitation image, as captured by the high-speed camera. However, the internal 3D structure of the developing cavitation cloud reveals a hollow vapour cloud ring formed at the hole entrance and extending only at the lower part of the hole due to the asymmetric flow entry. Moreover, the cavitation volume fraction exhibits a significant gradient along the orifice volume. The cavitation number and the needle valve lift seem to be the most influential operating parameters, while the Reynolds number seems to have only small effect for the range of values tested. Overall, the study demonstrates that use of micro-CT can be a reliable tool for cavitation in nozzle orifices operating under nominal steady-state conditions. (orig.)

  2. Micro-Computed Tomography Detection of Gold Nanoparticle-Labelled Mesenchymal Stem Cells in the Rat Subretinal Layer

    Science.gov (United States)

    Mok, Pooi Ling; Leow, Sue Ngein; Koh, Avin Ee-Hwan; Mohd Nizam, Hairul Harun; Ding, Suet Lee Shirley; Luu, Chi; Ruhaslizan, Raduan; Wong, Hon Seng; Halim, Wan Haslina Wan Abdul; Ng, Min Hwei; Idrus, Ruszymah Binti Hj.; Chowdhury, Shiplu Roy; Bastion, Catherine Mae-Lynn; Subbiah, Suresh Kumar; Higuchi, Akon; Alarfaj, Abdullah A.; Then, Kong Yong

    2017-01-01

    Mesenchymal stem cells are widely used in many pre-clinical and clinical settings. Despite advances in molecular technology; the migration and homing activities of these cells in in vivo systems are not well understood. Labelling mesenchymal stem cells with gold nanoparticles has no cytotoxic effect and may offer suitable indications for stem cell tracking. Here, we report a simple protocol to label mesenchymal stem cells using 80 nm gold nanoparticles. Once the cells and particles were incubated together for 24 h, the labelled products were injected into the rat subretinal layer. Micro-computed tomography was then conducted on the 15th and 30th day post-injection to track the movement of these cells, as visualized by an area of hyperdensity from the coronal section images of the rat head. In addition, we confirmed the cellular uptake of the gold nanoparticles by the mesenchymal stem cells using transmission electron microscopy. As opposed to other methods, the current protocol provides a simple, less labour-intensive and more efficient labelling mechanism for real-time cell tracking. Finally, we discuss the potential manipulations of gold nanoparticles in stem cells for cell replacement and cancer therapy in ocular disorders or diseases. PMID:28208719

  3. Compression-recovery model of absorptive glass mat (AGM) separator guided by X-ray micro-computed tomography analysis

    Science.gov (United States)

    Kameswara Rao, P. V.; Rawal, Amit; Kumar, Vijay; Rajput, Krishn Gopal

    2017-10-01

    Absorptive glass mat (AGM) separators play a key role in enhancing the cycle life of the valve regulated lead acid (VRLA) batteries by maintaining the elastic characteristics under a defined level of compression force with the plates of the electrodes. Inevitably, there are inherent challenges to maintain the required level of compression characteristics of AGM separators during the charge and discharge of the battery. Herein, we report a three-dimensional (3D) analytical model for predicting the compression-recovery behavior of AGM separators by formulating a direct relationship with the constituent fiber and structural parameters. The analytical model of compression-recovery behavior of AGM separators has successfully included the fiber slippage criterion and internal friction losses. The presented work uses, for the first time, 3D data of fiber orientation from X-ray micro-computed tomography, for predicting the compression-recovery behavior of AGM separators. A comparison has been made between the theoretical and experimental results of compression-recovery behavior of AGM samples with defined fiber orientation characteristics. In general, the theory agreed reasonably well with the experimental results of AGM samples in both dry and wet states. Through theoretical modeling, fiber volume fraction was established as one of the key structural parameters that modulates the compression hysteresis of an AGM separator.

  4. Application of X-ray micro-computed tomography on high-speed cavitating diesel fuel flows

    Science.gov (United States)

    Mitroglou, N.; Lorenzi, M.; Santini, M.; Gavaises, M.

    2016-11-01

    The flow inside a purpose built enlarged single-orifice nozzle replica is quantified using time-averaged X-ray micro-computed tomography (micro-CT) and high-speed shadowgraphy. Results have been obtained at Reynolds and cavitation numbers similar to those of real-size injectors. Good agreement for the cavitation extent inside the orifice is found between the micro-CT and the corresponding temporal mean 2D cavitation image, as captured by the high-speed camera. However, the internal 3D structure of the developing cavitation cloud reveals a hollow vapour cloud ring formed at the hole entrance and extending only at the lower part of the hole due to the asymmetric flow entry. Moreover, the cavitation volume fraction exhibits a significant gradient along the orifice volume. The cavitation number and the needle valve lift seem to be the most influential operating parameters, while the Reynolds number seems to have only small effect for the range of values tested. Overall, the study demonstrates that use of micro-CT can be a reliable tool for cavitation in nozzle orifices operating under nominal steady-state conditions.

  5. Application of X-ray micro-computed tomography on high-speed cavitating diesel fuel flows

    International Nuclear Information System (INIS)

    Mitroglou, N.; Lorenzi, M.; Gavaises, M.; Santini, M.

    2016-01-01

    The flow inside a purpose built enlarged single-orifice nozzle replica is quantified using time-averaged X-ray micro-computed tomography (micro-CT) and high-speed shadowgraphy. Results have been obtained at Reynolds and cavitation numbers similar to those of real-size injectors. Good agreement for the cavitation extent inside the orifice is found between the micro-CT and the corresponding temporal mean 2D cavitation image, as captured by the high-speed camera. However, the internal 3D structure of the developing cavitation cloud reveals a hollow vapour cloud ring formed at the hole entrance and extending only at the lower part of the hole due to the asymmetric flow entry. Moreover, the cavitation volume fraction exhibits a significant gradient along the orifice volume. The cavitation number and the needle valve lift seem to be the most influential operating parameters, while the Reynolds number seems to have only small effect for the range of values tested. Overall, the study demonstrates that use of micro-CT can be a reliable tool for cavitation in nozzle orifices operating under nominal steady-state conditions. (orig.)

  6. Construction of three-dimensional tooth model by micro-computed tomography and application for data sharing.

    Science.gov (United States)

    Kato, A; Ohno, N

    2009-03-01

    The study of dental morphology is essential in terms of phylogeny. Advances in three-dimensional (3D) measurement devices have enabled us to make 3D images of teeth without destruction of samples. However, raw fundamental data on tooth shape requires complex equipment and techniques. An online database of 3D teeth models is therefore indispensable. We aimed to explore the basic methodology for constructing 3D teeth models, with application for data sharing. Geometric information on the human permanent upper left incisor was obtained using micro-computed tomography (micro-CT). Enamel, dentine, and pulp were segmented by thresholding of different gray-scale intensities. Segmented data were separately exported in STereo-Lithography Interface Format (STL). STL data were converted to Wavefront OBJ (OBJect), as many 3D computer graphics programs support the Wavefront OBJ format. Data were also applied to Quick Time Virtual Reality (QTVR) format, which allows the image to be viewed from any direction. In addition to Wavefront OBJ and QTVR data, the original CT series were provided as 16-bit Tag Image File Format (TIFF) images on the website. In conclusion, 3D teeth models were constructed in general-purpose data formats, using micro-CT and commercially available programs. Teeth models that can be used widely would benefit all those who study dental morphology.

  7. Volumetric quantification of bone-implant contact using micro-computed tomography analysis based on region-based segmentation

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Sung Won; Lee, Woo Jin; Choi, Soon Chul; Lee, Sam Sun; Heo, Min Suk; Huh, Kyung Hoe; Kim, Tae Il; Yi, Won Ji [Dental Research Institute, School of Dentistry, Seoul National University, Seoul (Korea, Republic of)

    2015-03-15

    We have developed a new method of segmenting the areas of absorbable implants and bone using region-based segmentation of micro-computed tomography (micro-CT) images, which allowed us to quantify volumetric bone-implant contact (VBIC) and volumetric absorption (VA). The simple threshold technique generally used in micro-CT analysis cannot be used to segment the areas of absorbable implants and bone. Instead, a region-based segmentation method, a region-labeling method, and subsequent morphological operations were successively applied to micro-CT images. The three-dimensional VBIC and VA of the absorbable implant were then calculated over the entire volume of the implant. Two-dimensional (2D) bone-implant contact (BIC) and bone area (BA) were also measured based on the conventional histomorphometric method. VA and VBIC increased significantly with as the healing period increased (p<0.05). VBIC values were significantly correlated with VA values (p<0.05) and with 2D BIC values (p<0.05). It is possible to quantify VBIC and VA for absorbable implants using micro-CT analysis using a region-based segmentation method.

  8. Potential Bone to Implant Contact Area of Short Versus Standard Implants: An In Vitro Micro-Computed Tomography Analysis.

    Science.gov (United States)

    Quaranta, Alessandro; DʼIsidoro, Orlando; Bambini, Fabrizio; Putignano, Angelo

    2016-02-01

    To compare the available potential bone-implant contact (PBIC) area of standard and short dental implants by micro-computed tomography (μCT) assessment. Three short implants with different diameters (4.5 × 6 mm, 4.1 × 7 mm, and 4.1 × 6 mm) and 2 standard implants (3.5 × 10 mm and 3.3 × 9 mm) with diverse design and surface features were scanned with μCT. Cross-sectional images were obtained. Image data were manually processed to find the plane that corresponds to the most coronal contact point between the crestal bone and implant. The available PBIC was calculated for each sample. Later on, the cross-sectional slices were processed by a 3-dimensional (3D) software, and 3D images of each sample were used for descriptive analysis and display the microtopography and macrotopography. The wide-diameter short implant (4.5 × 6 mm) showed the higher PBIC (210.89 mm) value followed by the standard (178.07 mm and 185.37 mm) and short implants (130.70 mm and 110.70 mm). Wide-diameter short implants show a surface area comparable with standard implants. Micro-CT analysis is a promising technique to evaluate surface area in dental implants with different macrodesign, microdesign, and surface features.

  9. Volumetric quantification of bone-implant contact using micro-computed tomography analysis based on region-based segmentation

    International Nuclear Information System (INIS)

    Kang, Sung Won; Lee, Woo Jin; Choi, Soon Chul; Lee, Sam Sun; Heo, Min Suk; Huh, Kyung Hoe; Kim, Tae Il; Yi, Won Ji

    2015-01-01

    We have developed a new method of segmenting the areas of absorbable implants and bone using region-based segmentation of micro-computed tomography (micro-CT) images, which allowed us to quantify volumetric bone-implant contact (VBIC) and volumetric absorption (VA). The simple threshold technique generally used in micro-CT analysis cannot be used to segment the areas of absorbable implants and bone. Instead, a region-based segmentation method, a region-labeling method, and subsequent morphological operations were successively applied to micro-CT images. The three-dimensional VBIC and VA of the absorbable implant were then calculated over the entire volume of the implant. Two-dimensional (2D) bone-implant contact (BIC) and bone area (BA) were also measured based on the conventional histomorphometric method. VA and VBIC increased significantly with as the healing period increased (p<0.05). VBIC values were significantly correlated with VA values (p<0.05) and with 2D BIC values (p<0.05). It is possible to quantify VBIC and VA for absorbable implants using micro-CT analysis using a region-based segmentation method.

  10. Assessment of residual coronal tooth structure postendodontic cavity preparation using digital dental impressions and micro-computed tomography.

    Science.gov (United States)

    Al-Nuaimi, Nassr; Patel, Shanon; Foschi, Federico; Mannocci, Francesco; Austin, Rupert S

    To evaluate the in vitro accuracy of digital impressions for three-dimensional (3D) volumetric measurement of residual coronal tooth structure postendodontic cavity preparation, with reference to micro-computed tomography (μCT). Quantification of the accuracy and precision of the intraoral digital scanner (3M True Definition Scanner - IOS) was performed using a metrology gauge block and a profilometric calibration model. Thirty-four human extracted molars with endodontic access cavities were scanned using both intraoral scanning (test scanner) in high-resolution mode, and µCT (reference scanner: GE Locus SP μCT scanner) in high- (HiResCT) and low- (LoResCT) resolution modes. Comparisons of volumetric accuracy and 3D profilometric deviations were performed using surface metrology software. One-way repeated measures analysis of variance (ANOVA), in combination with the Bonferroni post hoc test, was implemented to compare the differences in volume measurements between scanning methods. Digital scanning revealed smaller volume measurements by 1.36% and 0.68% compared to HiResCT and LoResCT, respectively. There was a statistically significant difference in the volumetric measurements obtained from the IOS scanner and both HiResCT and LoResCT scans (P digital scanner was able to reliably measure the extra- and intracoronal aspect of the endodontically accessed tooth.

  11. Contrast enhanced micro-computed tomography resolves the 3-dimensional morphology of the cardiac conduction system in mammalian hearts.

    Directory of Open Access Journals (Sweden)

    Robert S Stephenson

    Full Text Available The general anatomy of the cardiac conduction system (CCS has been known for 100 years, but its complex and irregular three-dimensional (3D geometry is not so well understood. This is largely because the conducting tissue is not distinct from the surrounding tissue by dissection. The best descriptions of its anatomy come from studies based on serial sectioning of samples taken from the appropriate areas of the heart. Low X-ray attenuation has formerly ruled out micro-computed tomography (micro-CT as a modality to resolve internal structures of soft tissue, but incorporation of iodine, which has a high molecular weight, into those tissues enhances the differential attenuation of X-rays and allows visualisation of fine detail in embryos and skeletal muscle. Here, with the use of a iodine based contrast agent (I(2KI, we present contrast enhanced micro-CT images of cardiac tissue from rat and rabbit in which the three major subdivisions of the CCS can be differentiated from the surrounding contractile myocardium and visualised in 3D. Structures identified include the sinoatrial node (SAN and the atrioventricular conduction axis: the penetrating bundle, His bundle, the bundle branches and the Purkinje network. Although the current findings are consistent with existing anatomical representations, the representations shown here offer superior resolution and are the first 3D representations of the CCS within a single intact mammalian heart.

  12. Enabling three-dimensional densitometric measurements using laboratory source X-ray micro-computed tomography

    Science.gov (United States)

    Pankhurst, M. J.; Fowler, R.; Courtois, L.; Nonni, S.; Zuddas, F.; Atwood, R. C.; Davis, G. R.; Lee, P. D.

    2018-01-01

    We present new software allowing significantly improved quantitative mapping of the three-dimensional density distribution of objects using laboratory source polychromatic X-rays via a beam characterisation approach (c.f. filtering or comparison to phantoms). One key advantage is that a precise representation of the specimen material is not required. The method exploits well-established, widely available, non-destructive and increasingly accessible laboratory-source X-ray tomography. Beam characterisation is performed in two stages: (1) projection data are collected through a range of known materials utilising a novel hardware design integrated into the rotation stage; and (2) a Python code optimises a spectral response model of the system. We provide hardware designs for use with a rotation stage able to be tilted, yet the concept is easily adaptable to virtually any laboratory system and sample, and implicitly corrects the image artefact known as beam hardening.

  13. Complex Odontoma: A Case Report with Micro-Computed Tomography Findings

    Directory of Open Access Journals (Sweden)

    L. A. N. Santos

    2016-01-01

    Full Text Available Odontomas are the most common benign tumors of odontogenic origin. They are normally diagnosed on routine radiographs, due to the absence of symptoms. Histopathologic evaluation confirms the diagnosis especially in cases of complex odontoma, which may be confused during radiographic examination with an osteoma or other highly calcified bone lesions. The micro-CT is a new technology that enables three-dimensional analysis with better spatial resolution compared with cone beam computed tomography. Another great advantage of this technology is that the sample does not need special preparation or destruction in the sectioned area as in histopathologic evaluation. An odontoma with CBCT and microtomography images is presented in a 26-year-old man. It was first observed on panoramic radiographs and then by CBCT. The lesion and the impacted third molar were surgically excised using a modified Neumann approach. After removal, it was evaluated by histopathology and microtomography to confirm the diagnostic hypothesis. According to the results, micro-CT enabled the assessment of the sample similar to histopathology, without destruction of the sample. With further development, micro-CT could be a powerful diagnostic tool in future research.

  14. Optimizing a micro-computed tomography-based surrogate measurement of bone-implant contact.

    Science.gov (United States)

    Meagher, Matthew J; Parwani, Rachna N; Virdi, Amarjit S; Sumner, Dale R

    2018-03-01

    Histology and backscatter scanning electron microscopy (bSEM) are the current gold standard methods for quantifying bone-implant contact (BIC), but are inherently destructive. Microcomputed tomography (μCT) is a non-destructive alternative, but attempts to validate μCT-based assessment of BIC in animal models have produced conflicting results. We previously showed in a rat model using a 1.5 mm diameter titanium implant that the extent of the metal-induced artefact precluded accurate measurement of bone sufficiently close to the interface to assess BIC. Recently introduced commercial laboratory μCT scanners have smaller voxels and improved imaging capabilities, possibly overcoming this limitation. The goals of the present study were to establish an approach for optimizing μCT imaging parameters and to validate μCT-based assessment of BIC. In an empirical parametric study using a 1.5 mm diameter titanium implant, we determined 90 kVp, 88 µA, 1.5 μm isotropic voxel size, 1600 projections/180°, and 750 ms integration time to be optimal. Using specimens from an in vivo rat experiment, we found significant correlations between bSEM and μCT for BIC with the manufacturer's automated analysis routine (r = 0.716, p = 0.003) or a line-intercept method (r = 0.797, p = 0.010). Thus, this newer generation scanner's improved imaging capability reduced the extent of the metal-induced artefact zone enough to permit assessment of BIC. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:979-986, 2018. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  15. Limitations of using micro-computed tomography to predict bone-implant contact and mechanical fixation.

    Science.gov (United States)

    Liu, S; Broucek, J; Virdi, A S; Sumner, D R

    2012-01-01

    Fixation of metallic implants to bone through osseointegration is important in orthopaedics and dentistry. Model systems for studying this phenomenon would benefit from a non-destructive imaging modality so that mechanical and morphological endpoints can more readily be examined in the same specimens. The purpose of this study was to assess the utility of an automated microcomputed tomography (μCT) program for predicting bone-implant contact (BIC) and mechanical fixation strength in a rat model. Femurs in which 1.5-mm-diameter titanium implants had been in place for 4 weeks were either embedded in polymethylmethacrylate (PMMA) for preparation of 1-mm-thick cross-sectional slabs (16 femurs: 32 slabs) or were used for mechanical implant pull-out testing (n= 18 femurs). All samples were scanned by μCT at 70 kVp with 16 μm voxels and assessed by the manufacturer's software for assessing 'osseointegration volume per total volume' (OV/TV). OV/TV measures bone volume per total volume (BV/TV) in a 3-voxel-thick ring that by default excludes the 3 voxels immediately adjacent to the implant to avoid metal-induced artefacts. The plastic-embedded samples were also analysed by backscatter scanning electron microscopy (bSEM) to provide a direct comparison of OV/TV with a well-accepted technique for BIC. In μCT images in which the implant was directly embedded within PMMA, there was a zone of elevated attenuation (>50% of the attenuation value used to segment bone from marrow) which extended 48 μm away from the implant surface. Comparison of the bSEM and μCT images showed high correlations for BV/TV measurements in areas not affected by metal-induced artefacts. In addition for bSEM images, we found that there were high correlations between peri-implant BV/TV within 12 μm of the implant surface and BIC (correlation coefficients ≥0.8, p implant pull-out strength (r= 0.401, p= 0.049) and energy to failure (r= 0.435, p= 0.035). Thus, the need for the 48-μm-thick exclusion

  16. Automated segmentation of synchrotron radiation micro-computed tomography biomedical images using Graph Cuts and neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Alvarenga de Moura Meneses, Anderson, E-mail: ameneses@ieee.org [Radiological Sciences Laboratory, Rio de Janeiro State University, Rua Sao Francisco Xavier 524, CEP 20550-900, RJ (Brazil); Giusti, Alessandro [IDSIA (Dalle Molle Institute for Artificial Intelligence), University of Lugano (Switzerland); Pereira de Almeida, Andre; Parreira Nogueira, Liebert; Braz, Delson [Nuclear Engineering Program, Federal University of Rio de Janeiro, RJ (Brazil); Cely Barroso, Regina [Laboratory of Applied Physics on Biomedical Sciences, Physics Department, Rio de Janeiro State University, RJ (Brazil); Almeida, Carlos Eduardo de [Radiological Sciences Laboratory, Rio de Janeiro State University, Rua Sao Francisco Xavier 524, CEP 20550-900, RJ (Brazil)

    2011-12-21

    Synchrotron Radiation (SR) X-ray micro-Computed Tomography ({mu}CT) enables magnified images to be used as a non-invasive and non-destructive technique with a high space resolution for the qualitative and quantitative analyses of biomedical samples. The research on applications of segmentation algorithms to SR-{mu}CT is an open problem, due to the interesting and well-known characteristics of SR images for visualization, such as the high resolution and the phase contrast effect. In this article, we describe and assess the application of the Energy Minimization via Graph Cuts (EMvGC) algorithm for the segmentation of SR-{mu}CT biomedical images acquired at the Synchrotron Radiation for MEdical Physics (SYRMEP) beam line at the Elettra Laboratory (Trieste, Italy). We also propose a method using EMvGC with Artificial Neural Networks (EMANNs) for correcting misclassifications due to intensity variation of phase contrast, which are important effects and sometimes indispensable in certain biomedical applications, although they impair the segmentation provided by conventional techniques. Results demonstrate considerable success in the segmentation of SR-{mu}CT biomedical images, with average Dice Similarity Coefficient 99.88% for bony tissue in Wistar Rats rib samples (EMvGC), as well as 98.95% and 98.02% for scans of Rhodnius prolixus insect samples (Chagas's disease vector) with EMANNs, in relation to manual segmentation. The techniques EMvGC and EMANNs cope with the task of performing segmentation in images with the intensity variation due to phase contrast effects, presenting a superior performance in comparison to conventional segmentation techniques based on thresholding and linear/nonlinear image filtering, which is also discussed in the present article.

  17. Characterization of the porous structures of the green body and sintered biomedical titanium scaffolds with micro-computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Arifvianto, B., E-mail: b.arifvianto@tudelft.nl; Leeflang, M.A.; Zhou, J.

    2016-11-15

    The present research was aimed at gaining an understanding of the porous structure changes from the green body through water leaching and sintering to titanium scaffolds. Micro-computed tomography (micro-CT) was performed to generate 3D models of titanium scaffold preforms containing carbamide space-holding particles and sintered scaffolds containing macro- and micro-pores. The porosity values and structural parameters were determined by means of image analysis. The result showed that the porosity values, macro-pore sizes, connectivity densities and specific surface areas of the titanium scaffolds sintered at 1200 °C for 3 h did not significantly deviate from those of the green structures with various volume fractions of the space holder. Titanium scaffolds with a maximum specific surface area could be produced with an addition of 60–65 vol% carbamide particles to the matrix powder. The connectivity of pores inside the scaffold increased with rising volume fraction of the space holder. The shrinkage of the scaffolds prepared with > 50 vol% carbamide space holder, occurring during sintering, was caused by the reductions of macro-pore sizes and micro-pore sizes as well as the thickness of struts. In conclusion, the final porous structural characteristics of titanium scaffolds could be estimated from those of the green body. - Highlights: •Porous structures of green body and sintered titanium scaffolds was studied. •Porous structures of both samples were quantitatively characterized with micro-CT. •Porous structures of scaffolds could be controlled from the green body. •Shrinkage mechanisms of titanium scaffolds during sintering was established.

  18. Use of Micro-Computed Tomography for Dental Studies in Modern and Fossil Odontocetes: Potential Applications and Limitations

    Directory of Open Access Journals (Sweden)

    Carolina Loch

    2013-10-01

    Full Text Available Teeth are important elements in studies of modern and fossil Cetacea (whales, dolphins, providing information on feeding habits, estimations of age and phylogenetic relationships. The growth layer groups (GLGs recorded in dentine have demonstrated application for aging studies, but also have the potential to elucidate life history phenomena such as metabolic or physiologic events. Micro-Computed Tomography (Micro-CT is a non-invasive and non-destructive technique that allows 3-dimensional study of mineralized tissues, such as human teeth, and their physical properties. Teeth from extant dolphins (Cetacea: Odontoceti and some fossil odontocetes were scanned in a Skyscan 1172 Micro-CT desktop system. X-rays were generated at 100 kV and 100 µA for extant samples, and at 80kV and 124 µA for fossils. 0.5 mm thick aluminum and copper filters were used in the beam. Reconstructed images were informative for most extant species, showing a good resolution of the enamel layer, dentine and pulp cavity. Greyscale changes in the dentinal layers were not resolved enough to show GLGs. Visualization of the internal structure in fossil cetacean teeth depended on the degree of diagenetic alteration in the specimen; undifferentiated enamel and dentine regions probably reflect secondary mineralization. However, internal details were finely resolved for one fossil specimen, showing the enamel, internal layers of dentine and the pulp cavity. Micro-CT has been proven to be a useful tool for resolving the internal morphology of fossil and extant teeth of cetaceans before they are sectioned for other morphological analyses; however some methodological refinements are still necessary to allow better resolution of dentine for potential application in non-destructive age determination studies.

  19. Micro-Computed Tomography Analysis of the Root Canal Morphology of Palatal Roots of Maxillary First Molars.

    Science.gov (United States)

    Marceliano-Alves, Marília; Alves, Flávio Rodrigues Ferreira; Mendes, Daniel de Melo; Provenzano, José Claudio

    2016-02-01

    A thorough knowledge of root canal anatomy is critical for successful root canal treatments. This study evaluated the internal anatomy of the palatal roots of maxillary first molars with micro-computed tomography (microCT). The palatal roots of extracted maxillary first molars (n = 169) were scanned with microCT to determine several anatomic parameters, including main canal classification, lateral canal occurrence and location, degree of curvature, main foramen position, apical constriction presence, diameters 1 and 2 mm from the apex and 1 mm from the foramen, minor dentin thickness in those regions, canal volume, surface area, and convexity. All canals were classified as Vertucci type I. The cross sections were oval in 61% of the canals. Lateral canals were found in 25% of the samples. The main foramen did not coincide with the root apex in 95% of the cases. Only 8% of the canals were classified as straight. Apical constriction was identified in 38% of the roots. The minor and major canal diameters and minor dentin thickness were decreased near the apex. The minor dentin thickness 1 mm from the foramen was 0.82 mm. The palatal canals exhibited a volume of 6.91 mm(3) and surface area of 55.31 mm(2) and were rod-shaped. The root canals of the palatal roots were classified as type I. However, some factors need to be considered during the treatment of these roots, including the frequent ocurrence of moderate/severe curvatures, oval-shaped cross-sections, and lateral canals, noncoincidence of the apical foramen with the root apex, and absence of apical constriction in most cases. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  20. Quantitative pre-clinical screening of therapeutics for joint diseases using contrast enhanced micro-computed tomography.

    Science.gov (United States)

    Willett, N J; Thote, T; Hart, M; Moran, S; Guldberg, R E; Kamath, R V

    2016-09-01

    The development of effective therapies for cartilage protection has been limited by a lack of efficient quantitative cartilage imaging modalities in pre-clinical in vivo models. Our objectives were two-fold: first, to validate a new contrast-enhanced 3D imaging analysis technique, equilibrium partitioning of an ionic contrast agent-micro computed tomography (EPIC-μCT), in a rat medial meniscal transection (MMT) osteoarthritis (OA) model; and second, to quantitatively assess the sensitivity of EPIC-μCT to detect the effects of matrix metalloproteinase inhibitor (MMPi) therapy on cartilage degeneration. Rats underwent MMT surgery and tissues were harvested at 1, 2, and 3 weeks post-surgery or rats received an MMPi or vehicle treatment and tissues harvested 3 weeks post-surgery. Parameters of disease progression were evaluated using histopathology and EPIC-μCT. Correlations and power analyses were performed to compare the techniques. EPIC-μCT was shown to provide simultaneous 3D quantification of multiple parameters, including cartilage degeneration and osteophyte formation. In MMT animals treated with MMPi, OA progression was attenuated, as measured by 3D parameters such as lesion volume and osteophyte size. A post-hoc power analysis showed that 3D parameters for EPIC-μCT were more sensitive than 2D parameters requiring fewer animals to detect a therapeutic effect of MMPi. 2D parameters were comparable between EPIC-μCT and histopathology. This study demonstrated that EPIC-μCT has high sensitivity to provide 3D structural and compositional measurements of cartilage and bone in the joint. EPIC-μCT can be used in combination with histology to provide a comprehensive analysis to screen new potential therapies. Copyright © 2016 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  1. Non-destructive, high-content analysis of wheat grain traits using X-ray micro computed tomography

    Directory of Open Access Journals (Sweden)

    Nathan Hughes

    2017-11-01

    Full Text Available Abstract Background Wheat is one of the most widely grown crop in temperate climates for food and animal feed. In order to meet the demands of the predicted population increase in an ever-changing climate, wheat production needs to dramatically increase. Spike and grain traits are critical determinants of final yield and grain uniformity a commercially desired trait, but their analysis is laborious and often requires destructive harvest. One of the current challenges is to develop an accurate, non-destructive method for spike and grain trait analysis capable of handling large populations. Results In this study we describe the development of a robust method for the accurate extraction and measurement of spike and grain morphometric parameters from images acquired by X-ray micro-computed tomography (μCT. The image analysis pipeline developed automatically identifies plant material of interest in μCT images, performs image analysis, and extracts morphometric data. As a proof of principle, this integrated methodology was used to analyse the spikes from a population of wheat plants subjected to high temperatures under two different water regimes. Temperature has a negative effect on spike height and grain number with the middle of the spike being the most affected region. The data also confirmed that increased grain volume was correlated with the decrease in grain number under mild stress. Conclusions Being able to quickly measure plant phenotypes in a non-destructive manner is crucial to advance our understanding of gene function and the effects of the environment. We report on the development of an image analysis pipeline capable of accurately and reliably extracting spike and grain traits from crops without the loss of positional information. This methodology was applied to the analysis of wheat spikes can be readily applied to other economically important crop species.

  2. Micro-computed tomography assessment of human alveolar bone: bone density and three-dimensional micro-architecture.

    Science.gov (United States)

    Kim, Yoon Jeong; Henkin, Jeffrey

    2015-04-01

    Micro-computed tomography (micro-CT) is a valuable means to evaluate and secure information related to bone density and quality in human necropsy samples and small live animals. The aim of this study was to assess the bone density of the alveolar jaw bones in human cadaver, using micro-CT. The correlation between bone density and three-dimensional micro architecture of trabecular bone was evaluated. Thirty-four human cadaver jaw bone specimens were harvested. Each specimen was scanned with micro-CT at resolution of 10.5 μm. The bone volume fraction (BV/TV) and the bone mineral density (BMD) value within a volume of interest were measured. The three-dimensional micro architecture of trabecular bone was assessed. All the parameters in the maxilla and the mandible were subject to comparison. The variables for the bone density and the three-dimensional micro architecture were analyzed for nonparametric correlation using Spearman's rho at the significance level of p architecture parameters were consistently higher in the mandible, up to 3.3 times greater than those in the maxilla. The most linear correlation was observed between BV/TV and BMD, with Spearman's rho = 0.99 (p = .01). Both BV/TV and BMD were highly correlated with all micro architecture parameters with Spearman's rho above 0.74 (p = .01). Two aspects of bone density using micro-CT, the BV/TV and BMD, are highly correlated with three-dimensional micro architecture parameters, which represent the quality of trabecular bone. This noninvasive method may adequately enhance evaluation of the alveolar bone. © 2013 Wiley Periodicals, Inc.

  3. Potential and limitations of X-Ray micro-computed tomography in arthropod neuroanatomy: A methodological and comparative survey

    Science.gov (United States)

    Sombke, Andy; Lipke, Elisabeth; Michalik, Peter; Uhl, Gabriele; Harzsch, Steffen

    2015-01-01

    Classical histology or immunohistochemistry combined with fluorescence or confocal laser scanning microscopy are common techniques in arthropod neuroanatomy, and these methods often require time-consuming and difficult dissections and sample preparations. Moreover, these methods are prone to artifacts due to compression and distortion of tissues, which often result in information loss and especially affect the spatial relationships of the examined parts of the nervous system in their natural anatomical context. Noninvasive approaches such as X-ray micro-computed tomography (micro-CT) can overcome such limitations and have been shown to be a valuable tool for understanding and visualizing internal anatomy and structural complexity. Nevertheless, knowledge about the potential of this method for analyzing the anatomy and organization of nervous systems, especially of taxa with smaller body size (e.g., many arthropods), is limited. This study set out to analyze the brains of selected arthropods with micro-CT, and to compare these results with available histological and immunohistochemical data. Specifically, we explored the influence of different sample preparation procedures. Our study shows that micro-CT is highly suitable for analyzing arthropod neuroarchitecture in situ and allows specific neuropils to be distinguished within the brain to extract quantitative data such as neuropil volumes. Moreover, data acquisition is considerably faster compared with many classical histological techniques. Thus, we conclude that micro-CT is highly suitable for targeting neuroanatomy, as it reduces the risk of artifacts and is faster than classical techniques. J. Comp. Neurol. 523:1281–1295, 2015. © 2015 Wiley Periodicals, Inc. PMID:25728683

  4. Automated segmentation of synchrotron radiation micro-computed tomography biomedical images using Graph Cuts and neural networks

    International Nuclear Information System (INIS)

    Alvarenga de Moura Meneses, Anderson; Giusti, Alessandro; Pereira de Almeida, André; Parreira Nogueira, Liebert; Braz, Delson; Cely Barroso, Regina; Almeida, Carlos Eduardo de

    2011-01-01

    Synchrotron Radiation (SR) X-ray micro-Computed Tomography (μCT) enables magnified images to be used as a non-invasive and non-destructive technique with a high space resolution for the qualitative and quantitative analyses of biomedical samples. The research on applications of segmentation algorithms to SR-μCT is an open problem, due to the interesting and well-known characteristics of SR images for visualization, such as the high resolution and the phase contrast effect. In this article, we describe and assess the application of the Energy Minimization via Graph Cuts (EMvGC) algorithm for the segmentation of SR-μCT biomedical images acquired at the Synchrotron Radiation for MEdical Physics (SYRMEP) beam line at the Elettra Laboratory (Trieste, Italy). We also propose a method using EMvGC with Artificial Neural Networks (EMANNs) for correcting misclassifications due to intensity variation of phase contrast, which are important effects and sometimes indispensable in certain biomedical applications, although they impair the segmentation provided by conventional techniques. Results demonstrate considerable success in the segmentation of SR-μCT biomedical images, with average Dice Similarity Coefficient 99.88% for bony tissue in Wistar Rats rib samples (EMvGC), as well as 98.95% and 98.02% for scans of Rhodnius prolixus insect samples (Chagas's disease vector) with EMANNs, in relation to manual segmentation. The techniques EMvGC and EMANNs cope with the task of performing segmentation in images with the intensity variation due to phase contrast effects, presenting a superior performance in comparison to conventional segmentation techniques based on thresholding and linear/nonlinear image filtering, which is also discussed in the present article.

  5. Internal structures of scaffold-free 3D cell cultures visualized by synchrotron radiation-based micro-computed tomography

    Science.gov (United States)

    Saldamli, Belma; Herzen, Julia; Beckmann, Felix; Tübel, Jutta; Schauwecker, Johannes; Burgkart, Rainer; Jürgens, Philipp; Zeilhofer, Hans-Florian; Sader, Robert; Müller, Bert

    2008-08-01

    Recently the importance of the third dimension in cell biology has been better understood, resulting in a re-orientation towards three-dimensional (3D) cultivation. Yet adequate tools for their morphological characterization have to be established. Synchrotron radiation-based micro computed tomography (SRμCT) allows visualizing such biological systems with almost isotropic micrometer resolution, non-destructively. We have applied SRμCT for studying the internal morphology of human osteoblast-derived, scaffold-free 3D cultures, termed histoids. Primary human osteoblasts, isolated from femoral neck spongy bone, were grown as 2D culture in non-mineralizing osteogenic medium until a rather thick, multi-cellular membrane was formed. This delicate system was intentionally released to randomly fold itself. The folded cell cultures were grown to histoids of cubic milli- or centimeter size in various combinations of mineralizing and non-mineralizing osteogenic medium for a total period of minimum 56 weeks. The SRμCT-measurements were performed in the absorption contrast mode at the beamlines BW 2 and W 2 (HASYLAB at DESY, Hamburg, Germany), operated by the GKSS-Research Center. To investigate the entire volume of interest several scans were performed under identical conditions and registered to obtain one single dataset of each sample. The histoids grown under different conditions exhibit similar external morphology of globular or ovoid shape. The SRμCT-examination revealed the distinctly different morphological structures inside the histoids. One obtains details of the histoids that permit to identify and select the most promising slices for subsequent histological characterization.

  6. Analysis of mandibular second molars with fused roots and shallow radicular grooves by using micro-computed tomography.

    Science.gov (United States)

    Amoroso-Silva, Pablo; De Moraes, Ivaldo Gomes; Marceliano-Alves, Marilia; Bramante, Clovis Monteiro; Zapata, Ronald Ordinola; Hungaro Duarte, Marco Antonio

    2018-01-01

    This study aimed to describe the morphological and morphometric aspects of fused mandibular second molars with radicular shallow grooves using micro-computed tomography (CT). Eighty-eight mandibular second molars with fused roots were scanned in a micro-CT scanner at a voxel size of 19.6 μm. After reconstruction, only molars without C-shaped roots and presenting shallow radicular grooves were selected. 30 molars were chosen for further analysis. Canal cross-sections were classified according to Fan's modified classification (C1, C2, C3, and C4) and morphometric parameters at the apical region, examination of accessory foramina and tridimensional configuration were evaluated. Three-dimensional reconstructions indicated a higher prevalence of merging type ( n = 22). According to Fan's modified classification, the C4 configuration was predominant in the 3 apical mm. Roundness median values revealed a more round-shaped canals at 3 mm (0.72) than at 2 (0.63) and 1 (0.61) mm from the apex. High values of major and minor diameters were observed in the canals of these evaluated sections. In addition, few accessory apical foramina were observed at 1 and 2 mm from the apex. The average distance between last accessory foramina and the anatomic apex was 1.17 mm. A less complex internal anatomy is found when a mandibular second molar presents fused roots with shallow radicular grooves. The merging type canal was frequently observed. Moreover, the C4 configuration was predominant at a point 3 mm from the apex and presented rounded canals, large apical diameters, and few accessory foramina. The cervical and middle thirds presented C3 and C1 canal configurations most frequently. A minor morphological complexity is found when fused mandibular second molars present shallow radicular grooves.

  7. The dental cavities of equine cheek teeth: three-dimensional reconstructions based on high resolution micro-computed tomography

    Directory of Open Access Journals (Sweden)

    Kopke Susan

    2012-09-01

    Full Text Available Abstract Background Recent studies reported on the very complex morphology of the pulp system in equine cheek teeth. The continuous production of secondary dentine leads to distinct age-related changes of the endodontic cavity. Detailed anatomical knowledge of the dental cavities in all ages is required to explain the aetiopathology of typical equine endodontic diseases. Furthermore, data on mandibular and maxillary pulp systems is in high demand to provide a basis for the development of endodontic therapies. However, until now examination of the pulp cavity has been based on either sectioned teeth or clinical computed tomography. More precise results were expected by using micro-computed tomography with a resolution of about 0.1 mm and three-dimensional reconstructions based on previous greyscale analyses and histological verification. The aim of the present study was to describe the physiological configurations of the pulp system within a wide spectrum of tooth ages. Results Maxillary teeth: All morphological constituents of the endodontic cavity were present in teeth between 4 and 16 years: Triadan 06s displayed six pulp horns and five root canals, Triadan 07-10s five pulp horns and four root canals and Triadan 11s seven pulp horns and four to six root canals. A common pulp chamber was most frequent in teeth ≤5 years, but was found even in a tooth of 9 years. A large variety of pulp configurations was observed within 2.5 and 16 years post eruption, but most commonly a separation into mesial and distal pulp compartments was seen. Maxillary cheek teeth showed up to four separate pulp compartments but the frequency of two, three and four pulp compartments was not related to tooth age (P > 0.05. In Triadan 06s, pulp horn 6 was always connected to pulp horns 1 and 3 and root canal I. In Triadan 11s, pulp horns 7 and 8 were present in variable constitutions. Mandibular teeth: A common pulp chamber was present in teeth up to 15 years, but most

  8. Three-dimensional evaluation of human jaw bone microarchitecture: correlation between the microarchitectural parameters of cone beam computed tomography and micro-computer tomography.

    Science.gov (United States)

    Kim, Jo-Eun; Yi, Won-Jin; Heo, Min-Suk; Lee, Sam-Sun; Choi, Soon-Chul; Huh, Kyung-Hoe

    2015-12-01

    To evaluate the potential feasibility of cone beam computed tomography (CBCT) in the assessment of trabecular bone microarchitecture. Sixty-eight specimens from four pairs of human jaw were scanned using both micro-computed tomography (micro-CT) of 19.37-μm voxel size and CBCT of 100-μm voxel size. The correlation of 3-dimensional parameters between CBCT and micro-CT was evaluated. All parameters, except bone-specific surface and trabecular thickness, showed linear correlations between the 2 imaging modalities (P < .05). Among the parameters, bone volume, percent bone volume, trabecular separation, and degree of anisotropy (DA) of CBCT images showed strong correlations with those of micro-CT images. DA showed the strongest correlation (r = 0.693). Most microarchitectural parameters from CBCT were correlated with those from micro-CT. Some microarchitectural parameters, especially DA, could be used as strong predictors of bone quality in the human jaw. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Micro-computed tomography pore-scale study of flow in porous media: Effect of voxel resolution

    Science.gov (United States)

    Shah, S. M.; Gray, F.; Crawshaw, J. P.; Boek, E. S.

    2016-09-01

    A fundamental understanding of flow in porous media at the pore-scale is necessary to be able to upscale average displacement processes from core to reservoir scale. The study of fluid flow in porous media at the pore-scale consists of two key procedures: Imaging - reconstruction of three-dimensional (3D) pore space images; and modelling such as with single and two-phase flow simulations with Lattice-Boltzmann (LB) or Pore-Network (PN) Modelling. Here we analyse pore-scale results to predict petrophysical properties such as porosity, single-phase permeability and multi-phase properties at different length scales. The fundamental issue is to understand the image resolution dependency of transport properties, in order to up-scale the flow physics from pore to core scale. In this work, we use a high resolution micro-computed tomography (micro-CT) scanner to image and reconstruct three dimensional pore-scale images of five sandstones (Bentheimer, Berea, Clashach, Doddington and Stainton) and five complex carbonates (Ketton, Estaillades, Middle Eastern sample 3, Middle Eastern sample 5 and Indiana Limestone 1) at four different voxel resolutions (4.4 μm, 6.2 μm, 8.3 μm and 10.2 μm), scanning the same physical field of view. Implementing three phase segmentation (macro-pore phase, intermediate phase and grain phase) on pore-scale images helps to understand the importance of connected macro-porosity in the fluid flow for the samples studied. We then compute the petrophysical properties for all the samples using PN and LB simulations in order to study the influence of voxel resolution on petrophysical properties. We then introduce a numerical coarsening scheme which is used to coarsen a high voxel resolution image (4.4 μm) to lower resolutions (6.2 μm, 8.3 μm and 10.2 μm) and study the impact of coarsening data on macroscopic and multi-phase properties. Numerical coarsening of high resolution data is found to be superior to using a lower resolution scan because it

  10. Evaluating the hydraulic and transport properties of peat soil using pore network modeling and X-ray micro computed tomography

    Science.gov (United States)

    Gharedaghloo, Behrad; Price, Jonathan S.; Rezanezhad, Fereidoun; Quinton, William L.

    2018-06-01

    Micro-scale properties of peat pore space and their influence on hydraulic and transport properties of peat soils have been given little attention so far. Characterizing the variation of these properties in a peat profile can increase our knowledge on the processes controlling contaminant transport through peatlands. As opposed to the common macro-scale (or bulk) representation of groundwater flow and transport processes, a pore network model (PNM) simulates flow and transport processes within individual pores. Here, a pore network modeling code capable of simulating advective and diffusive transport processes through a 3D unstructured pore network was developed; its predictive performance was evaluated by comparing its results to empirical values and to the results of computational fluid dynamics (CFD) simulations. This is the first time that peat pore networks have been extracted from X-ray micro-computed tomography (μCT) images of peat deposits and peat pore characteristics evaluated in a 3D approach. Water flow and solute transport were modeled in the unstructured pore networks mapped directly from μCT images. The modeling results were processed to determine the bulk properties of peat deposits. Results portray the commonly observed decrease in hydraulic conductivity with depth, which was attributed to the reduction of pore radius and increase in pore tortuosity. The increase in pore tortuosity with depth was associated with more decomposed peat soil and decreasing pore coordination number with depth, which extended the flow path of fluid particles. Results also revealed that hydraulic conductivity is isotropic locally, but becomes anisotropic after upscaling to core-scale; this suggests the anisotropy of peat hydraulic conductivity observed in core-scale and field-scale is due to the strong heterogeneity in the vertical dimension that is imposed by the layered structure of peat soils. Transport simulations revealed that for a given solute, the effective

  11. Prediction of primary breast cancer size and T-stage using micro-computed tomography in lumpectomy specimens

    Directory of Open Access Journals (Sweden)

    Wafa M Sarraj

    2015-01-01

    Full Text Available Background: Histopathology is the only accepted method to measure and stage the breast tumor size. However, there is a need to find another method to measure and stage the tumor size when the pathological assessment is not available. Micro-computed tomography. (micro-CT has the ability to measure tumor in three dimensions in an intact lumpectomy specimen. In this study, we aimed to determine the accuracy of micro-CT to measure and stage the primary tumor size in breast lumpectomy specimens, as compared to the histopathology. Materials and Methods: Seventy-two women who underwent lumpectomy surgery at the Massachusetts General Hospital Department of Surgery from June 2011 to September 2011, and from August 2013 to December 2013 participated in this study. The lumpectomy specimens were scanned using micro-CT followed by routine pathological processing. The maximum dimension of the invasive breast tumor was obtained from the micro-CT image and was compared to the corresponding pathology report for each subject. Results: The invasive tumor size measurement by micro-CT was underestimated in 24. cases. (33%, overestimated in 37. cases. (51%, and matched it exactly in 11. cases. (15% compared to the histopathology measurement for all the cases. However, micro-CT T.stage classification differed from histopathology in only 11. (15.2% with 6. cases. (8.3% classified as a higher stage by micro-CT, and 5. cases. (6.9% classified as lower compared to histopathology. In addition, micro-CT demonstrated a statically significant strong agreement (κ =0.6, P < 0.05 with pathological tumor size and staging for invasive ductal carcinoma. (IDC group. In contrast, there was no agreement. (κ = .2, P = 0.67 between micro-CT and pathology in estimating and staging tumor size for invasive lobular carcinoma. (ILC group. This could be explained by a small sample size. (7 for ILC group. Conclusions: Micro-CT is a promising modality for measuring and staging the IDC.

  12. Head and Neck Veins of the Mouse. A Magnetic Resonance, Micro Computed Tomography and High Frequency Color Doppler Ultrasound Study.

    Directory of Open Access Journals (Sweden)

    Marcello Mancini

    Full Text Available To characterize the anatomy of the venous outflow of the mouse brain using different imaging techniques. Ten C57/black male mice (age range: 7-8 weeks were imaged with high-frequency Ultrasound, Magnetic Resonance Angiography and ex-vivo Microcomputed tomography of the head and neck. Under general anesthesia, Ultrasound of neck veins was performed with a 20 MHz transducer; head and neck Magnetic Resonance Angiography data were collected on 9.4 T or 7 T scanners, and ex-vivo Microcomputed tomography angiography was obtained by filling the vessels with a radiopaque inert silicone rubber compound. All procedures were approved by the local ethical committee. The dorsal intracranial venous system is quite similar in mice and humans. Instead, the mouse Internal Jugular Veins are tiny vessels receiving the sigmoid sinuses and tributaries from cerebellum, occipital lobe and midbrain, while the majority of the cerebral blood, i.e. from the olfactory bulbs and fronto-parietal lobes, is apparently drained through skull base connections into the External Jugular Vein. Three main intra-extracranial anastomoses, absent in humans, are: 1 the petrosquamous sinus, draining into the posterior facial vein, 2 the veins of the olfactory bulb, draining into the superficial temporal vein through a foramen of the frontal bone 3 the cavernous sinus, draining in the External Jugular Vein through a foramen of the sphenoid bone. The anatomical structure of the mouse cranial venous outflow as depicted by Ultrasound, Microcomputed tomography and Magnetic Resonance Angiography is different from humans, with multiple connections between intra- and extra-cranial veins.

  13. Validation of Optical Coherence Tomography against Micro-computed Tomography for Evaluation of Remaining Coronal Dentin Thickness.

    Science.gov (United States)

    Majkut, Patrycja; Sadr, Alireza; Shimada, Yasushi; Sumi, Yasunori; Tagami, Junji

    2015-08-01

    Optical coherence tomography (OCT) is a noninvasive modality to obtain in-depth images of biological structures. A dental OCT system has become available for chairside application. This in vitro study hypothesized that swept-source OCT can be used to measure the remaining dentin thickness (RDT) at the roof of the dental pulp chamber during excavation of deep caries. Human molar teeth with deep occlusal caries were investigated. After obtaining 2-dimensional and 3-dimensional OCT scans using a swept-source OCT system at a 1330-nm center wavelength, RDT was evaluated by image analysis software. Microfocus x-ray computed tomographic (micro-CT) images were obtained from the same cross sections to confirm OCT findings. The smallest RDT values at the visible pulp horn were measured on OCT and micro-CT imaging and compared using the Pearson correlation. Pulpal horns and pulp chamber roof observation under OCT and micro-CT imaging resulted in comparable images that allowed the measurement of coronal dentin thickness. RDT measured by OCT showed optical values range between 140 and 2300 μm, which corresponded to the range of 92-1524 μm on micro-CT imaging. A strong correlation was found between the 2 techniques (r = 0.96, P structures during deep caries excavation. Exposure of the vital dental pulp because of the removal of very thin remaining coronal dentin can be avoided with this novel noninvasive technique. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  14. X-Ray Micro-Computed Tomography of Apollo Samples as a Curation Technique Enabling Better Research

    Science.gov (United States)

    Ziegler, R. A.; Almeida, N. V.; Sykes, D.; Smith, C. L.

    2014-01-01

    X-ray micro-computed tomography (micro-CT) is a technique that has been used to research meteorites for some time and many others], and recently it is becoming a more common tool for the curation of meteorites and Apollo samples. Micro-CT is ideally suited to the characterization of astromaterials in the curation process as it can provide textural and compositional information at a small spatial resolution rapidly, nondestructively, and without compromising the cleanliness of the samples (e.g., samples can be scanned sealed in Teflon bags). This data can then inform scientists and curators when making and processing future sample requests for meteorites and Apollo samples. Here we present some preliminary results on micro-CT scans of four Apollo regolith breccias. Methods: Portions of four Apollo samples were used in this study: 14321, 15205, 15405, and 60639. All samples were 8-10 cm in their longest dimension and approximately equant. These samples were micro-CT scanned on the Nikon HMXST 225 System at the Natural History Museum in London. Scans were made at 205-220 kV, 135-160 microamps beam current, with an effective voxel size of 21-44 microns. Results: Initial examination of the data identify a variety of mineral clasts (including sub-voxel FeNi metal grains) and lithic clasts within the regolith breccias. Textural information within some of the lithic clasts was also discernable. Of particular interest was a large basalt clast (approx.1.3 cc) found within sample 60639, which appears to have a sub-ophitic texture. Additionally, internal void space, e.g., fractures and voids, is readily identifiable. Discussion: It is clear from the preliminary data that micro-CT analyses are able to identify important "new" clasts within the Apollo breccias, and better characterize previously described clasts or igneous samples. For example, the 60639 basalt clast was previously believed to be quite small based on its approx.0.5 sq cm exposure on the surface of the main mass

  15. Technical aspects of X-ray micro-computed tomography. Initial experience of 27-μm resolution using feldkamp cone-beam reconstruction

    International Nuclear Information System (INIS)

    Yamamoto, Shuji; Suzuki, Masahiro; Kohara, Kazushi; Iinuma, Gen; Moriyama, Noriyuki

    2007-01-01

    The objective of this study was to introduce the technical utility of micro-computed tomography (CT) with 27-μm resolution by cone-beam CT algorithm. Whole-body micro-CT scans were performed to honeybee. Two- and three-dimensional image analyses were performed by originally developed and available open-source software for acquired images. The original contribution of this work is to describe the technical characteristics of the X-ray micro-CT system, keeping a small experimental insect in a unique condition. Micro-CT may be used as a rapid prototyping tool to research and understand the high-resolution system with Feldkamp cone-beam reconstruction. (author)

  16. Stereological measures of trabecular bone structure: comparison of 3D micro computed tomography with 2D histological sections in human proximal tibial bone biopsies

    DEFF Research Database (Denmark)

    Thomsen, Jesper Skovhus; Laib, A.; Koller, B.

    2005-01-01

    Stereology applied on histological sections is the 'gold standard' for obtaining quantitative information on cancellous bone structure. Recent advances in micro computed tomography (microCT) have made it possible to acquire three-dimensional (3D) data non-destructively. However, before the 3D...... methods can be used as a substitute for the current 'gold standard' they have to be verified against the existing standard. The aim of this study was to compare bone structural measures obtained from 3D microCT data sets with those obtained by stereology performed on conventional histological sections...... tibial metaphysis. The biopsies were embedded in methylmetacrylate before microCT scanning in a Scanco microCT 40 scanner at a resolution of 20 x 20 x 20 microm3, and the 3D data sets were analysed with a computer program. After microCT scanning, 16 sections were cut from the central 2 mm of each biopsy...

  17. Apical Root Canal Morphology of Mesial Roots of Mandibular First Molar Teeth with Vertucci Type II Configuration by Means of Micro-Computed Tomography.

    Science.gov (United States)

    Keleş, Ali; Keskin, Cangül

    2017-03-01

    The aim of this study was to assess the features of the apical root canal anatomy and its relation to the level at which 2 separate root canals merge in the mesial roots of the mandibular first molars with Vertucci type II canal configuration by using micro-computed tomography analysis. The anatomic features of the apical 3 mm of root canals in 83 mesial roots of mandibular first molar teeth were investigated by micro-computed tomography and software imaging according to the level at which 2 separate root canals merge. The most apical slice where a visible root canal was detectable was recorded as 0 level. The specimens from where 2 root canals rejoin at within 3 mm from the 0 level were then assigned to group 1 (n = 37), whereas the specimens from where root canals rejoin 3-9 mm from the 0 level were assigned to group 2 (n = 46). Data were presented by using descriptive statistics and Mann-Whitney U tests, with the significance level set at 5%. In all specimens the long oval type of cross-sectional shape increased from 50.9% at 1 mm to 80.5% at 3 mm. Group 1 presented significantly higher major diameter values compared with group 2 (P  .05) between groups. Group 2 displayed significantly higher roundness values than group 1 (P < .05). A long oval root cross section of apical root canal anatomy is more prevalent in roots for which 2 root canals merge within apical 3 mm of root canals. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  18. Adjunctive Steps for Disinfection of the Mandibular Molar Root Canal System: A Correlative Bacteriologic, Micro-Computed Tomography, and Cryopulverization Approach.

    Science.gov (United States)

    Alves, Flávio R F; Andrade-Junior, Carlos V; Marceliano-Alves, Marília F; Pérez, Alejandro R; Rôças, Isabela N; Versiani, Marco A; Sousa-Neto, Manoel D; Provenzano, José C; Siqueira, José F

    2016-11-01

    This study evaluated the disinfecting ability of chemomechanical preparation with rotary nickel-titanium instruments, followed by 2 distinct adjunctive procedures in the root canals of extracted mandibular molars by means of a correlative analytical approach. Twenty-two extracted mandibular molars were selected and anatomically matched between groups on the basis of micro-computed tomographic analysis. In the first phase of the experiment, root canals were contaminated with Enterococcus faecalis and subjected to chemomechanical preparation with BT RaCe instruments and 2.5% NaOCl irrigation. Then either XP-Endo Finisher instrument or passive ultrasonic irrigation was used to supplement disinfection. Micro-computed tomography was used to show whether the percentage of unprepared areas correlated to bacterial counts. In the second phase, the same teeth were contaminated once again, and the adjunctive procedures were used. Samples from the isthmus area of mesial roots and the apical 5-mm fragment of distal roots were obtained by cryopulverization. Samples taken before and after treatment steps in both phases were evaluated by quantitative polymerase chain reaction and statistically analyzed. In phase 1, preparation in both groups resulted in substantial decrease of bacterial counts (P  .05). In phase 2, both methods had significant antibacterial effects in the main canal, but none of them could predictably disinfect the isthmus/recess areas. Both XP-Endo Finisher and passive ultrasonic irrigation exhibited antibacterial effectiveness, but only the former caused a significant reduction in the bacterial counts after chemomechanical preparation. None of them were effective in predictably disinfecting the isthmus/recess areas. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  19. Peri-implant osseointegration after low-level laser therapy: micro-computed tomography and resonance frequency analysis in an animal model.

    Science.gov (United States)

    Mayer, Luciano; Gomes, Fernando Vacilotto; de Oliveira, Marília Gerhardt; de Moraes, João Feliz Duarte; Carlsson, Lennart

    2016-12-01

    The purpose of the present study is to evaluate the effects of low-level laser therapy on the osseointegration process by comparing resonance frequency analysis measurements performed at implant placement and after 30 days and micro-computed tomography images in irradiated vs nonirradiated rabbits. Fourteen male New Zealand rabbits were randomly divided into two groups of seven animals each, one control group (nonirradiated animals) and one experimental group that received low-level laser therapy (Thera Lase®, aluminum-gallium-arsenide laser diode, 10 J per spot, two spots per session, seven sessions, 830 nm, 50 mW, CW, Ø 0.0028 cm 2 ). The mandibular left incisor was surgically extracted in all animals, and one osseointegrated implant was placed immediately afterward (3.25ø × 11.5 mm; NanoTite, BIOMET 3i). Resonance frequency analysis was performed with the Osstell® device at implant placement and at 30 days (immediately before euthanasia). Micro-computed tomography analyses were then conducted using a high-resolution scanner (SkyScan 1172 X-ray Micro-CT) to evaluate the amount of newly formed bone around the implants. Irradiated animals showed significantly higher implant stability quotients at 30 days (64.286 ± 1.596; 95 % confidence interval (CI) 60.808-67.764) than controls (56.357 ± 1.596; 95 %CI 52.879-59.835) (P = .000). The percentage of newly formed bone around the implants was also significantly higher in irradiated animals (75.523 ± 8.510; 95 %CI 61.893-89.155) than in controls (55.012 ± 19.840; 95 %CI 41.380-68.643) (P = .027). Laser therapy, based on the irradiation protocol used in this study, was able to provide greater implant stability and increase the volume of peri-implant newly formed bone, indicating that laser irradiation effected an improvement in the osseointegration process.

  20. Comparison of canal transportation and centering ability of hand Protaper files and rotary Protaper files by using micro computed tomography

    OpenAIRE

    Amit Gandhi; Taru Gandhi

    2011-01-01

    Introduction and objective: The aim of the present study was to compare root canal preparation with rotary ProTaper files and hand ProTaper files to find a better instrumentation technique for maintaining root canal geometry with the aid of computed tomography. Material and methods: Twenty curved root canals with at least 10 degree of curvature were divided into 2 groups of 10 teeth each. In group I the canals were prepared with hand ProTaper files and in group II the canals were prepared wit...

  1. A Micro-computed Tomography Evaluation of the Shaping Ability of Two Nickel-titanium Instruments, HyFlex EDM and ProTaper Next.

    Science.gov (United States)

    Venino, Pier Matteo; Citterio, Claudio Luigi; Pellegatta, Alberto; Ciccarelli, Marta; Maddalone, Marcello

    2017-04-01

    The aim of this study was to evaluate and compare, by means of micro-computed tomography imaging, the shaping ability of ProTaper Next (PTN) and the novel HyFlex EDM (HFEDM) instruments. Forty teeth were randomly divided into 2 groups and prepared with PTN or HFEDM. Root canal transportation and centering ratio were evaluated in mesiodistal and buccolingual directions at 5 levels (at the midpoint of the apical, middle, and coronal thirds and at the boundaries between them). Variations in volume, surface, and cross-sectional shape were measured for the apical, middle, and coronal thirds. The null hypotheses were that no differences existed between the 2 groups. The D'Agostino-Pearson test (α = .05) was conducted to assess the normality of the data sets. The distributions were compared by using the Mann-Whitney test (α = .05). Statistically significant differences (P < .005) were recorded only for buccolingual canal transportation and centering ratio at the section between the middle and coronal thirds, where HFEDM files were superior. HFEDM and PTN files were similarly effective, and both safely prepared the root canals, respecting their original anatomies. HFEDM files performed better in terms of buccolingual canal transportation and centering ratio at the section between the middle and coronal thirds. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  2. Diagnostic Value of Ex-Vivo Three-Dimensional Micro-Computed Tomography Imaging of Primary Nonhematopoietic Human Bone Tumors: Osteosarcoma versus Chondrosarcoma

    Energy Technology Data Exchange (ETDEWEB)

    Langheinrich, A. C.; Stolle, C.; Kampschulte, M.; Lommel, D.; Rau, W. S.; Bassaly, B. (Depts. of Radiology and Pathology, Univ. of Giessen, Giessen (Germany))

    2008-10-15

    Background: Osteosarcoma and chondrosarcoma are the most common nonhematopoietic primary malignancies of bone. However, unusual radiographic appearances can lead to delay in diagnosis and confusion with benign diseases. Purpose: To evaluate the feasibility of micro-computed tomography (CT) for the analysis of primary, nonhematopoietic human bone tumors ex vivo. Material and Methods: Samples from 12 human bone specimens (osteosarcoma, n=6; chondrosarcoma, n=6) obtained for diagnostic purposes were scanned using industrial X-ray film without amplifier foil and scanned with micro-CT (7- and 12-mum-cubic voxels). Trabecular bone CT 'density' and tumor matrix CT 'density' were determined, and results were compared with those obtained from a detailed conventional histopathologic analysis of corresponding cross-sections. The significance of differences in grayscale measurements was tested with analysis of variance. Results: Micro-CT provided quantitative information on bone morphology equivalent to histopathological analysis. We established grayscale measurements by which tumor matrices of chondrosarcoma and osteosarcoma could be radiographically categorized following histological classifications (P<0.001). Conclusion: Micro-CT is feasible for the analysis and differentiation of human osteosarcoma and chondrosarcoma

  3. Micro-computed tomography (μCT) as a novel method in ecotoxicology--determination of morphometric and somatic data in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Brinkmann, Markus; Rizzo, Larissa Y; Lammers, Twan; Gremse, Felix; Schiwy, Sabrina; Kiessling, Fabian; Hollert, Henner

    2016-02-01

    Fish are important sentinel organisms for the assessment of water quality and play a central role in ecotoxicological research. Of particular importance to the assessment of health and fitness of fish stocks in response to environmental conditions or pollution are morphometric (e.g. Fulton's condition index) and somatic indices (e.g. hepatosomatic, and gonadosomatic index). Standard measurements of somatic indices are invasive and require, by definition, the sacrifice of examined animals, thus prohibiting longitudinal studies and relocation of animals captured in the field. As a potential solution, in the present study, we propose the use of micro-computed tomography (μCT) as imaging modality to non-invasively tomographically image rainbow trout (Oncorhynchus mykiss) exposed to different sediment suspensions. We here demonstrate that μCT can be used as a tool to reliably measure the volumes of different organs, which could then be applied as a substitute of their weights in calculation of somatic indices. To the best of our knowledge, this study is the first to report the results of μCT analyses in the context of ecotoxicological research in rainbow trout. It has the potential to greatly increase the information value of experiments conducted with fish and also to potentially reduce the number of animals required for studying temporal effects through facilitating longitudinal studies within the same individuals. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Micro-computed tomography and histomorphometric analysis of the effects of platelet-rich fibrin on bone regeneration in the rabbit calvarium.

    Science.gov (United States)

    Acar, Ahmet Hüseyin; Yolcu, Ümit; Gül, Mehmet; Keleş, Ali; Erdem, Necip Fazıl; Altundag Kahraman, Sevil

    2015-04-01

    The present study aimed to investigate the effectiveness of platelet-rich fibrin (PRF) on bone regeneration when used alone or in combination with hydroxyapatite (HA)/beta-tricalcium phosphate (βTCP). In this study, 20 New Zealand white rabbits were used and four calvarial defects were prepared in each animal. PRF, Straumann(®) Bone Ceramic (SBC), or PRF+SBC was applied to the defects; one defect was left untreated as a control. Ten rabbits were sacrificed at week 4 (T1) and 10 at week 8 (T2). After micro-computed tomography (micro-CT) scanning, the samples were sent for histological and histomorphometric analysis to evaluate and compare the volume and area of regenerated bone. Histomorphometric and micro-CT analysis showed that both PRF and SBC significantly increased bone regeneration at T1 and T2 (P<0.01). When PRF was used in combination with HA/βTCP, a further significant increase in new bone formation was observed at T1 and T2 compared with that when PRF or SBC was used alone (P<0.01). PRF has a positive effect on bone formation when used alone and in combination with HA/βTCP. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Influence of low-intensity pulsed ultrasound on osteogenic tissue regeneration in a periodontal injury model: X-ray image alterations assessed by micro-computed tomography.

    Science.gov (United States)

    Wang, Yunji; Chai, Zhaowu; Zhang, Yuanyuan; Deng, Feng; Wang, Zhibiao; Song, Jinlin

    2014-08-01

    This study was conducted to evaluate, with micro-computed tomography, the influence of low-intensity pulsed ultrasound on wound-healing in periodontal tissues. Periodontal disease with Class II furcation involvement was surgically produced at the bilateral mandibular premolars in 8 adult male beagle dogs. Twenty-four teeth were randomly assigned among 4 groups (G): G1, periodontal flap surgery; G2, periodontal flap surgery+low-intensity pulsed ultrasound (LIPUS); G3, guided tissue regeneration (GTR) surgery; G4, GTR surgery plus LIPUS. The affected area in the experimental group was exposed to LIPUS. At 6 and 8weeks, the X-ray images of regenerated teeth were referred to micro-CT scanning for 3-D measurement. Bone volume (BV), bone surface (BS), and number of trabeculae (Tb) in G2 and G4 were higher than in G1 and G3 (pperiodontal flap surgery group. LIPUS irradiation increased the number, volume, and area of new alveolar bone trabeculae. LIPUS has the potential to promote the repair of periodontal tissue, and may work effectively if combined with GTR. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Investigation of water and CO2 (carbon dioxide) flooding using micro-CT (micro-computed tomography) images of Berea sandstone core using finite element simulations

    International Nuclear Information System (INIS)

    Gunde, Akshay C.; Bera, Bijoyendra; Mitra, Sushanta K.

    2010-01-01

    The present study reports a numerical investigation of water and CO 2 (carbon dioxide) flooding at the pore scale of a porous medium. We use high resolution micro-computed tomography (micro-CT) images of Berea sandstone core to obtain the pore geometry. The numerical solution used for the simulation was carried out by a finite element based software package. Level Set method is used to determine the position of the interface between two immiscible fluids when oil is displaced by water and CO 2 , respectively. The present formulation is validated against single-phase flow through the porous structure. It is found that, fluid flow inside the pore space takes place through preferential inlet and outlet pores. For two-phase flow, it is observed that continuous displacement of oil occurs during water flooding but CO 2 is able to displace oil at certain locations in the pores. Also, the separation of flow front is observed in the case of CO 2 flooding. A quantitative comparison of the results obtained in two types of flooding simulations suggests that water displaces a higher volume of oil than CO 2 in the time period for which the simulations are performed.

  7. Assessment of three root canal preparation techniques on root canal geometry using micro-computed tomography: In vitro study

    Directory of Open Access Journals (Sweden)

    Shaikha M Al-Ali

    2012-01-01

    Full Text Available Aim: To assess the effects of three root canal preparation techniques on canal volume and surface area using three-dimensionally reconstructed root canals in extracted human maxillary molars. Materials and Methods: Thirty extracted Human Maxillary Molars having three separate roots and similar root shape were randomly selected from a pool of extracted teeth for this study and stored in normal saline solution until used. A computed tomography scanner (Philips Brilliance CT 64-slice was used to analyze root canals in extracted maxillary molars. Specimens were scanned before and after canals were prepared using stainless steel K-Files, Ni-Ti rotary ProTaper and rotary SafeSiders instruments. Differences in dentin volume removed, the surface area, the proportion of unchanged area and canal transportation were calculated using specially developed software. Results: Instrumentation of canals increased volume and surface area. Statistical analysis found a statistically significant difference among the 3 groups in total change in volume (P = 0.001 and total change in surface area (P = 0.13. Significant differences were found when testing both groups with group III (SafeSiders. Significant differences in change of volume were noted when grouping was made with respect to canal type (in MB and DB (P < 0.05. Conclusion: The current study used computed tomography, an innovative and non destructive technique, to illustrate changes in canal geometry. Overall, there were few statistically significant differences between the three instrumentation techniques used. SafeSiders stainless steel 40/0.02 instruments exhibit a greater cutting efficiency on dentin than K-Files and ProTaper. CT is a new and valuable tool to study root canal geometry and changes after preparation in great details. Further studies with 3D-techniques are required to fully understand the biomechanical aspects of root canal preparation.

  8. Non-contact respiration monitoring for in-vivo murine micro computed tomography: characterization and imaging applications

    International Nuclear Information System (INIS)

    Burk, Laurel M; Lee, Yueh Z; Wait, J Matthew; Lu Jianping; Zhou, Otto Z

    2012-01-01

    A cone beam micro-CT has previously been utilized along with a pressure-tracking respiration sensor to acquire prospectively gated images of both wild-type mice and various adult murine disease models. While the pressure applied to the abdomen of the subject by this sensor is small and is generally without physiological effect, certain disease models of interest, as well as very young animals, are prone to atelectasis with added pressure, or they generate too weak a respiration signal with this method to achieve optimal prospective gating. In this work we present a new fibre-optic displacement sensor which monitors respiratory motion of a subject without requiring physical contact. The sensor outputs an analogue signal which can be used for prospective respiration gating in micro-CT imaging. The device was characterized and compared against a pneumatic air chamber pressure sensor for the imaging of adult wild-type mice. The resulting images were found to be of similar quality with respect to physiological motion blur; the quality of the respiration signal trace obtained using the non-contact sensor was comparable to that of the pressure sensor and was superior for gating purposes due to its better signal-to-noise ratio. The non-contact sensor was then used to acquire in-vivo micro-CT images of a murine model for congenital diaphragmatic hernia and of 11-day-old mouse pups. In both cases, quality CT images were successfully acquired using this new respiration sensor. Despite the presence of beam hardening artefacts arising from the presence of a fibre-optic cable in the imaging field, we believe this new technique for respiration monitoring and gating presents an opportunity for in-vivo imaging of disease models which were previously considered too delicate for established animal handling methods. (paper)

  9. Variation in Lateral Plate Quality in Threespine Stickleback from Fresh, Brackish and Marine Water: A Micro-Computed Tomography Study.

    Directory of Open Access Journals (Sweden)

    Elisabeth Wiig

    Full Text Available It is important to understand the drivers leading to adaptive phenotypic diversity within and among species. The threespine stickleback (Gasterosteus aculeatus has become a model system for investigating the genetic and phenotypic responses during repeated colonization of fresh waters from the original marine habitat. During the freshwater colonization process there has been a recurrent and parallel reduction in the number of lateral bone plates, making it a suitable system for studying adaptability and parallel evolution.The aim of this study was to investigate an alternative evolutionary path of lateral plate reduction, where lateral plates are reduced in size rather than number.A total of 72 threespine stickleback individuals from freshwater (n = 54, brackish water (n = 27 and marine water (n = 9 were analysed using microcomputed tomography (μCT to determine variation in size, thickness and structure of the lateral plates. Furthermore, whole-body bone volume, and bone volume, bone surface and porosity of lateral plate number 4 were quantified in all specimens from each environment.The results showed a significant difference in plate size (area and volume among populations, where threespine stickleback from polymorphic freshwater and brackish water populations displayed lateral plates reduced in size (area and volume compared to marine stickleback.Reduction of lateral plates in threespine stickleback in fresh and brackish water occurs by both plate loss and reduction in plate size (area and volume.

  10. Micro-computed tomography derived anisotropy detects tumor provoked deviations in bone in an orthotopic osteosarcoma murine model.

    Directory of Open Access Journals (Sweden)

    Heather A Cole

    Full Text Available Radiographic imaging plays a crucial role in the diagnosis of osteosarcoma. Currently, computed-tomography (CT is used to measure tumor-induced osteolysis as a marker for tumor growth by monitoring the bone fractional volume. As most tumors primarily induce osteolysis, lower bone fractional volume has been found to correlate with tumor aggressiveness. However, osteosarcoma is an exception as it induces osteolysis and produces mineralized osteoid simultaneously. Given that competent bone is highly anisotropic (systematic variance in its architectural order renders its physical properties dependent on direction of load and that tumor induced osteolysis and osteogenesis are structurally disorganized relative to competent bone, we hypothesized that μCT-derived measures of anisotropy could be used to qualitatively and quantitatively detect osteosarcoma provoked deviations in bone, both osteolysis and osteogenesis, in vivo. We tested this hypothesis in a murine model of osteosarcoma cells orthotopically injected into the tibia. We demonstrate that, in addition to bone fractional volume, μCT-derived measure of anisotropy is a complete and accurate method to monitor osteosarcoma-induced osteolysis. Additionally, we found that unlike bone fractional volume, anisotropy could also detect tumor-induced osteogenesis. These findings suggest that monitoring tumor-induced changes in the structural property isotropy of the invaded bone may represent a novel means of diagnosing primary and metastatic bone tumors.

  11. Imaging study of pancreatic ductal adenocarcinomas in Syrian hamsters using X-ray micro-computed tomography (CT)

    International Nuclear Information System (INIS)

    Kitahashi, Tsukasa; Mutoh, Michihiro; Tsurusaki, Masakatsu

    2010-01-01

    X-ray computed tomography (CT) has been used for diagnoses of human pancreatic cancer. Although micro-CT is a useful approach to evaluate macromorphology of organs/tissue also in animal models, reports on pancreatic tumors are limited. In this study, the utility of micro-CT was assessed in characterizing chemically induced pancreatic tumors in Syrian hamsters. Hamsters treated with or without N-nitrosobis(2-oxopropyl)amine (BOP) were injected with the antispasmodic agent, scopolamine butylbromide, and contrast agents, 5 or 10 mL/kg body weight of iopamidol or Fenestra VC at 18-38 weeks, then examined by micro-CT scanning with a respiratory gating system. Both peristaltic and respiratory movements were substantially suppressed by the combination of scopolamine butylbromide treatment and the respiratory gating system, resulting in improvements of image qualities. Iopamidol clearly visualized the pancreatic parenchyma and contrasted the margins among the pancreas and other abdominal organs/tissue. Meanwhile Fenestra VC predominantly contrasted abdominal vascular systems, but the margins among pancreas and other organs/tissue remained obscure. Six pancreatic tumors of 4-13 mm in diameter were detected in four of 15 animals, but not the five tumors of 1-4 mm in diameter. The inner tumor images were heterogeneously or uniformly visualized by iopamidol and Fenestra VC. Overall, iopamidol could clearly contrast between pancreatic parenchyma and the tumors as compared with Fenestra VC. All tumors confirmed were histopathologically diagnosed as pancreatic ductal adenocarcinomas. Thus, micro-CT could be useful to evaluate the carcinogenic processes and preventive methods of pancreatic cancer in hamsters and to assess the novel contrast agents for detection of small pancreatic cancer in humans. (author)

  12. Radiological and micro-computed tomography analysis of the bone at dental implants inserted 2, 3 and 4 mm apart in a minipig model with platform switching incorporated.

    Science.gov (United States)

    Elian, Nicolas; Bloom, Mitchell; Dard, Michel; Cho, Sang-Choon; Trushkowsky, Richard D; Tarnow, Dennis

    2014-02-01

    The purpose of this study was to assess the effect of inter-implant distance on interproximal bone utilizing platform switching. Analysis of interproximal bone usually depends on traditional two-dimensional radiographic assessment. Although there has been increased reliability of current techniques, there has been an inability to track bone level changes over time and in three dimensions. Micro-CT has provided three-dimensional imaging that can be used in conjunction with traditional two-dimensional radiographic techniques. This study was performed on 24 female minipigs. Twelve animals received three implants with an inter-implant distance of 3 mm on one side of the mandible and another three implants on the contra-lateral side, where the implants were placed 2 mm apart creating a split mouth design. Twelve other animals received three implants with an inter-implant distance of 3 mm on one side of the mandible and another three implants on the contra-lateral side, where the implants were placed 4 mm apart creating a split mouth design too. The quantitative evaluation was performed comparatively on radiographs taken at t 0 (immediately after implantation) and at t 8 weeks (after termination). The samples were scanned by micro-computed tomography (μCT) to quantify the first bone to implant contact (fBIC) and bone volume/total volume (BV/TV). Mixed model regressions using the nonparametric Brunner-Langer method were used to determine the effect of inter-implant distance on the measured outcomes. The change in bone level was determined using radiography and its mean was 0.05 mm for an inter-implant distance of 3 and 0.00 mm for a 2 mm distance (P = 0.7268). The mean of this outcome was 0.18 mm for the 3 mm and for 4 mm inter-implant distance (P = 0.9500). Micro-computed tomography showed that the fBIC was always located above the reference, 0.27 and 0.20 mm for the comparison of 2-3 mm (P = 0.4622) and 0.49 and 0.34 mm for the inter-implant distance of 3 and 4 mm (P

  13. Micro-Computed-Tomography-Guided Analysis of In Vitro Structural Modifications in Two Types of 45S5 Bioactive Glass Based Scaffolds.

    Science.gov (United States)

    Westhauser, Fabian; Ciraldo, Francesca; Balasubramanian, Preethi; Senger, Anne-Sophie; Schmidmaier, Gerhard; Moghaddam, Arash; Boccaccini, Aldo R

    2017-11-23

    Three-dimensional 45S5 bioactive glass (BG)-based scaffolds are being investigated for bone regeneration. Besides structural properties, controlled time-dependent alteration of scaffold morphology is crucial to achieve optimal scaffold characteristics for successful bone repair. There is no in vitro evidence concerning the dependence between structural characteristics and dissolution behavior of 45S5 BG-based scaffolds of different morphology. In this study, the dissolution behavior of scaffolds fabricated by the foam replica method using polyurethane foam (Group A) and maritime sponge Spongia Agaricina (Group B) as sacrificial templates was analyzed by micro-computed-tomography (µCT). The scaffolds were immersed in Dulbecco's Modified Eagle Medium for 56 days under static cell culture conditions and underwent µCT-analysis initially, and after 7, 14, and 56 days. Group A showed high porosity (91%) and trabecular structure formed by macro-pores (average diameter 692 µm ± 72 µm). Group-B-scaffolds were less porous (51%), revealing an optimal pore size distribution within the window of 110-500 µm pore size diameter, combined with superior mechanical stability. Both groups showed similar structural alteration upon immersion. Surface area and scaffold volume increased whilst density decreased, reflecting initial dissolution followed by hydroxycarbonate-apatite-layer-formation on the scaffold surfaces. In vitro- and/or in vivo-testing of cell-seeded BG-scaffolds used in this study should be performed to evaluate the BG-scaffolds' time-dependent osteogenic properties in relation to the measured in vitro structural changes.

  14. [Comparison of effectiveness and safety between Twisted File technique and ProTaper Universal rotary full sequence based on micro-computed tomography].

    Science.gov (United States)

    Chen, Xiao-bo; Chen, Chen; Liang, Yu-hong

    2016-02-18

    To evaluate the efficacy and security of two type of rotary nickel titanium system (Twisted File and ProTaper Universal) for root canal preparation based on micro-computed tomography(micro-CT). Twenty extracted molars (including 62 canals) were divided into two experimental groups and were respectively instrumented using Twisted File rotary nickel titanium system (TF) and ProTaper Universal rotary nickel titanium system (PU) to #25/0.08 following recommended protocol. Time for root canal instrumentation (accumulation of time for every single file) was recorded. The 0-3 mm root surface from apex was observed under an optical stereomicroscope at 25 × magnification. The presence of crack line was noted. The root canals were scanned with micro-CT before and after root canal preparation. Three-dimensional shape images of canals were reconstructed, calculated and evaluated. The amount of canal central transportation of the two groups was calculated and compared. The shorter preparation time [(0.53 ± 0.14) min] was observed in TF group, while the preparation time of PU group was (2.06 ± 0.39) min (Pvs. (0.097 ± 0.084) mm, P<0.05]. No instrument separation was observed in both the groups. Cracks were not found in both the groups either based in micro-CT images or observation under an optical stereomicroscope at 25 × magnification. Compared with ProTaper Universal, Twisted File took less time in root canal preparation and exhibited better shaping ability, and less canal transportation.

  15. The influence of alendronate on the healing of extraction sockets of ovariectomized rats assessed by in vivo micro-computed tomography.

    Science.gov (United States)

    Jee, Jeong-Hyun; Lee, Wan; Lee, Byung Do

    2010-08-01

    Many dental patients take bisphosphonates to reduce the risk of hip and vertebral fractures. In vivo micro-computed tomography (micro-CT) was used to examine the longitudinal inhibitory effect of alendronate on the healing of extraction sockets in ovariectomized rats. Twenty 5-week-old Sprague-Dawley rats were assigned randomly to 1 of 3 groups: sham-operated (n = 5), and 2 ovariectomized (OVX) groups: saline treated (0.1 mL/100 g/d, n = 7) and alendronate treated (1 mg/kg/d, n = 8). Before micro-CT scanning, the left maxillary first molars of the rats were extracted. In vivo micro-CT (spatial resolution 50 x 50 mum) of the jaw was performed at baseline and at 2-week intervals for 6 weeks. Alveolar-bone radiographic densities and dimensions were analyzed with repeated measures analysis of variance. The bony healing patterns of the extraction sockets were also evaluated in each group. The radiographic socket densities of the sham-treated and OVX-alendronate groups significantly increased during the first 4 weeks after extraction (P sockets in the OVX-saline group increased, but the increase was significantly lower than for the other groups at 4 weeks (P sockets in all groups 2 to 6 weeks after extraction. There was a significant loss of alveolar ridge height at the second week postextraction compared with baseline, and at the fourth week compared with the second week (P sockets in estrogen-deficient rats and helps resist the loss of alveolar bone adjacent to extraction sockets. Copyright 2010 Mosby, Inc. All rights reserved.

  16. Three-dimensional quantification of orthodontic root resorption with time-lapsed imaging of micro-computed tomography in a rodent model.

    Science.gov (United States)

    Yang, Chongshi; Zhang, Yuanyuan; Zhang, Yan; Fan, Yubo; Deng, Feng

    2015-01-01

    Despite various X-ray approaches have been widely used to monitor root resorption after orthodontic treatment, a non-invasive and accurate method is highly desirable for long-term follow up. The aim of this study was to build a non-invasive method to quantify longitudinal orthodontic root resorption with time-lapsed images of micro-computed tomography (micro-CT) in a rodent model. Twenty male Sprague Dawley (SD) rats (aged 6-8 weeks, weighing 180-220 g) were used in this study. A 25 g orthodontic force generated by nickel-titanium coil spring was applied to the right maxillary first molar for each rat, while contralateral first molar was severed as a control. Micro-CT scan was performed at day 0 (before orthodontic load) and days 3, 7, 14, and 28 after orthodontic load. Resorption of mesial root of maxillary first molars at bilateral sides was calculated from micro-CT images with registration algorithm via reconstruction, superimposition and partition operations. Obvious resorption of mesial root of maxillary first molar can be detected at day 14 and day 28 at orthodontic side. Most of the resorption occurred in the apical region at distal side and cervical region at mesiolingual side. Desirable development of molar root of rats was identified from day 0 to day 28 at control side. The development of root concentrated on apical region. This non-invasive 3D quantification method with registration algorithm can be used in longitudinal study of root resorption. Obvious root resorption in rat molar can be observed three-dimensionally at day 14 and day 28 after orthodontic load. This indicates that registration algorithm combined with time-lapsed images provides clinic potential application in detection and quantification of root contour.

  17. Micro-Computed Tomography Evaluation of ProTaper Next and BioRace Shaping Outcomes in Maxillary First Molar Curved Canals.

    Science.gov (United States)

    Pasqualini, Damiano; Alovisi, Mario; Cemenasco, Andrea; Mancini, Lucia; Paolino, Davide Salvatore; Bianchi, Caterina Chiara; Roggia, Andrea; Scotti, Nicola; Berutti, Elio

    2015-10-01

    The aim of this micro-computed tomography study was to describe the shaping properties of ProGlider/ProTaper Next (PG/PTN) and ScoutRace/BioRace (SR/BR) nickel-titanium rotary systems. Thirty maxillary first permanent molars were selected. Mesiobuccal canals were randomly assigned (n = 15) to PG/PTN or SR/BR groups. Irrigation was performed with 5% NaOCl and 10% EDTA. Specimens were scanned (voxel size, 9.1 μm) for matching volumes and surface areas and post-treatment analyses. Root canal centering ability, canal geometry enlargement, and thickness of dentinal wall at inner curvature were assessed at apical level and point of maximum curvature. Results were analyzed with 4 one-way analyses of variance. Canal centering ability was superior in PG/PTN (P = .006 at apical level, P = .025 at point of maximum curvature). PG/PTN demonstrated a more conservative increase of canal areas (P = .027 at apical level, P = .038 at point of maximum curvature). Centrifugal increase in canal diameters did not significantly differ between groups (P = .65 at apical level, P = .61 at point of maximum curvature). Inner dentinal wall thickness was less reduced with PG/PTN compared with SR/BR, with no statistical differences (P = .23 at point of maximum curvature, P = .89 at apical level). PG/PTN shaping taper ranged between 6% and 7%. Neither system produced significant shaping errors in curved canals. PG/PTN system showed better preservation of canal anatomy. PTN offset section did not influence final preparation taper. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  18. Micro-computed tomography (μCT) as a novel method in ecotoxicology — determination of morphometric and somatic data in rainbow trout (Oncorhynchus mykiss)

    Energy Technology Data Exchange (ETDEWEB)

    Brinkmann, Markus, E-mail: markus.brinkmann@bio5.rwth-aachen.de [Department of Ecosystem Analysis, Institute for Environmental Research, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Rizzo, Larissa Y.; Lammers, Twan; Gremse, Felix [Department of Experimental Molecular Imaging, Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Aachen (Germany); Schiwy, Sabrina [Department of Ecosystem Analysis, Institute for Environmental Research, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Kiessling, Fabian [Department of Experimental Molecular Imaging, Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Aachen (Germany); Hollert, Henner, E-mail: henner.hollert@bio5.rwth-aachen.de [Department of Ecosystem Analysis, Institute for Environmental Research, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); College of Resources and Environmental Science, Chongqing University, 1 Tiansheng Road Beibei, Chongqing 400715 (China); College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, 1239 Siping Road, Shanghai (China); State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University (China)

    2016-02-01

    Fish are important sentinel organisms for the assessment of water quality and play a central role in ecotoxicological research. Of particular importance to the assessment of health and fitness of fish stocks in response to environmental conditions or pollution are morphometric (e.g. Fulton's condition index) and somatic indices (e.g. hepatosomatic, and gonadosomatic index). Standard measurements of somatic indices are invasive and require, by definition, the sacrifice of examined animals, thus prohibiting longitudinal studies and relocation of animals captured in the field. As a potential solution, in the present study, we propose the use of micro-computed tomography (μCT) as imaging modality to non-invasively tomographically image rainbow trout (Oncorhynchus mykiss) exposed to different sediment suspensions. We here demonstrate that μCT can be used as a tool to reliably measure the volumes of different organs, which could then be applied as a substitute of their weights in calculation of somatic indices. To the best of our knowledge, this study is the first to report the results of μCT analyses in the context of ecotoxicological research in rainbow trout. It has the potential to greatly increase the information value of experiments conducted with fish and also to potentially reduce the number of animals required for studying temporal effects through facilitating longitudinal studies within the same individuals. - Highlights: • μCT was used for volumetric imaging sediment-exposed and unexposed rainbow trout • Liver volumes determined by μCT were highly correlated with liver weights. • The perfusion of organs in fish could also be studied by means of μCT. • It was shown that μCT is a useful tool in context of ecotoxicological research.

  19. Micro-Computed-Tomography-Guided Analysis of In Vitro Structural Modifications in Two Types of 45S5 Bioactive Glass Based Scaffolds

    Directory of Open Access Journals (Sweden)

    Fabian Westhauser

    2017-11-01

    Full Text Available Three-dimensional 45S5 bioactive glass (BG-based scaffolds are being investigated for bone regeneration. Besides structural properties, controlled time-dependent alteration of scaffold morphology is crucial to achieve optimal scaffold characteristics for successful bone repair. There is no in vitro evidence concerning the dependence between structural characteristics and dissolution behavior of 45S5 BG-based scaffolds of different morphology. In this study, the dissolution behavior of scaffolds fabricated by the foam replica method using polyurethane foam (Group A and maritime sponge Spongia Agaricina (Group B as sacrificial templates was analyzed by micro-computed-tomography (µCT. The scaffolds were immersed in Dulbecco’s Modified Eagle Medium for 56 days under static cell culture conditions and underwent µCT-analysis initially, and after 7, 14, and 56 days. Group A showed high porosity (91% and trabecular structure formed by macro-pores (average diameter 692 µm ± 72 µm. Group-B-scaffolds were less porous (51%, revealing an optimal pore size distribution within the window of 110–500 µm pore size diameter, combined with superior mechanical stability. Both groups showed similar structural alteration upon immersion. Surface area and scaffold volume increased whilst density decreased, reflecting initial dissolution followed by hydroxycarbonate-apatite-layer-formation on the scaffold surfaces. In vitro- and/or in vivo-testing of cell-seeded BG-scaffolds used in this study should be performed to evaluate the BG-scaffolds’ time-dependent osteogenic properties in relation to the measured in vitro structural changes.

  20. Bone regeneration by the osteoconductivity of porous titanium implants manufactured by selective laser melting: a histological and micro computed tomography study in the rabbit.

    Science.gov (United States)

    de Wild, Michael; Schumacher, Ralf; Mayer, Kyrill; Schkommodau, Erik; Thoma, Daniel; Bredell, Marius; Kruse Gujer, Astrid; Grätz, Klaus W; Weber, Franz E

    2013-12-01

    The treatment of large bone defects still poses a major challenge in orthopaedic and cranio-maxillofacial surgery. One possible solution could be the development of personalized porous titanium-based implants that are designed to meet all mechanical needs with a minimum amount of titanium and maximum osteopromotive properties so that it could be combined with growth factor-loaded hydrogels or cell constructs to realize advanced bone tissue engineering strategies. Such implants could prove useful for mandibular reconstruction, spinal fusion, the treatment of extended long bone defects, or to fill in gaps created on autograft harvesting. The aim of this study was to determine the mechanical properties and potential of bone formation of light weight implants generated by selective laser melting (SLM). We mainly focused on osteoconduction, as this is a key feature in bone healing and could serve as a back-up for osteoinduction and cell transplantation strategies. To that end, defined implants were produced by SLM, and their surfaces were left untreated, sandblasted, or sandblasted/acid etched. In vivo bone formation with the different implants was tested throughout calvarial defects in rabbits and compared with untreated defects. Analysis by micro computed tomography (μCT) and histomorphometry revealed that all generatively produced porous Ti structures were well osseointegrated into the surrounding bone. The histomorphometric analysis revealed that bone formation was significantly increased in all implant-treated groups compared with untreated defects and significantly increased in sand blasted implants compared with untreated ones. Bone bridging was significantly increased in sand blasted acid-etched scaffolds. Therefore, scaffolds manufactured by SLM should be surface treated. Bone augmentation beyond the original bone margins was only seen in implant-treated defects, indicating an osteoconductive potential of the implants that could be utilized clinically for bone

  1. Micro-computed tomography (μCT) as a novel method in ecotoxicology — determination of morphometric and somatic data in rainbow trout (Oncorhynchus mykiss)

    International Nuclear Information System (INIS)

    Brinkmann, Markus; Rizzo, Larissa Y.; Lammers, Twan; Gremse, Felix; Schiwy, Sabrina; Kiessling, Fabian; Hollert, Henner

    2016-01-01

    Fish are important sentinel organisms for the assessment of water quality and play a central role in ecotoxicological research. Of particular importance to the assessment of health and fitness of fish stocks in response to environmental conditions or pollution are morphometric (e.g. Fulton's condition index) and somatic indices (e.g. hepatosomatic, and gonadosomatic index). Standard measurements of somatic indices are invasive and require, by definition, the sacrifice of examined animals, thus prohibiting longitudinal studies and relocation of animals captured in the field. As a potential solution, in the present study, we propose the use of micro-computed tomography (μCT) as imaging modality to non-invasively tomographically image rainbow trout (Oncorhynchus mykiss) exposed to different sediment suspensions. We here demonstrate that μCT can be used as a tool to reliably measure the volumes of different organs, which could then be applied as a substitute of their weights in calculation of somatic indices. To the best of our knowledge, this study is the first to report the results of μCT analyses in the context of ecotoxicological research in rainbow trout. It has the potential to greatly increase the information value of experiments conducted with fish and also to potentially reduce the number of animals required for studying temporal effects through facilitating longitudinal studies within the same individuals. - Highlights: • μCT was used for volumetric imaging sediment-exposed and unexposed rainbow trout • Liver volumes determined by μCT were highly correlated with liver weights. • The perfusion of organs in fish could also be studied by means of μCT. • It was shown that μCT is a useful tool in context of ecotoxicological research.

  2. Micro-Scale Distribution of CA4+ in Ex Vivo Human Articular Cartilage Detected with Contrast-Enhanced Micro-Computed Tomography Imaging

    Science.gov (United States)

    Karhula, Sakari S.; Finnilä, Mikko A.; Freedman, Jonathan D.; Kauppinen, Sami; Valkealahti, Maarit; Lehenkari, Petri; Pritzker, Kenneth P. H.; Nieminen, Heikki J.; Snyder, Brian D.; Grinstaff, Mark W.; Saarakkala, Simo

    2017-08-01

    Contrast-enhanced micro-computed tomography (CEµCT) with cationic and anionic contrast agents reveals glycosaminoglycan (GAG) content and distribution in articular cartilage (AC). The advantage of using cationic stains (e.g. CA4+) compared to anionic stains (e.g. Hexabrix®), is that it distributes proportionally with GAGs, while anionic stain distribution in AC is inversely proportional to the GAG content. To date, studies using cationic stains have been conducted with sufficient resolution to study its distributions on the macro-scale, but with insufficient resolution to study its distributions on the micro-scale. Therefore, it is not known whether the cationic contrast agents accumulate in extra/pericellular matrix and if they interact with chondrocytes. The insufficient resolution has also prevented to answer the question whether CA4+ accumulation in chondrons could lead to an erroneous quantification of GAG distribution with low-resolution µCT setups. In this study, we use high-resolution µCT to investigate whether CA4+ accumulates in chondrocytes, and further, to determine whether it affects the low-resolution ex vivo µCT studies of CA4+ stained human AC with varying degree of osteoarthritis. Human osteochondral samples were immersed in three different concentrations of CA4+ (3 mgI/ml, 6mgI/ml, and 24 mgI/ml) and imaged with high-resolution µCT at several timepoints. Different uptake diffusion profiles of CA4+ were observed between the segmented chondrons and the rest of the tissue. While the X-ray -detected CA4+ concentration in chondrons was greater than in the rest of the AC, its contribution to the uptake into the whole tissue was negligible and in line with macro-scale GAG content detected from histology. The efficient uptake of CA4+ into chondrons and surrounding territorial matrix can be explained by the micro-scale distribution of GAG content. CA4+ uptake in chondrons occurred regardless of the progression stage of osteoarthritis in the samples

  3. Micro-Scale Distribution of CA4+ in Ex vivo Human Articular Cartilage Detected with Contrast-Enhanced Micro-Computed Tomography Imaging

    Directory of Open Access Journals (Sweden)

    Sakari S. Karhula

    2017-08-01

    Full Text Available Contrast-enhanced micro-computed tomography (CEμCT with cationic and anionic contrast agents reveals glycosaminoglycan (GAG content and distribution in articular cartilage (AC. The advantage of using cationic stains (e.g., CA4+ compared to anionic stains (e.g., Hexabrix®, is that it distributes proportionally with GAGs, while anionic stain distribution in AC is inversely proportional to the GAG content. To date, studies using cationic stains have been conducted with sufficient resolution to study its distributions on the macro-scale, but with insufficient resolution to study its distributions on the micro-scale. Therefore, it is not known whether the cationic contrast agents accumulate in extra/pericellular matrix and if they interact with chondrocytes. The insufficient resolution has also prevented to answer the question whether CA4+ accumulation in chondrons could lead to an erroneous quantification of GAG distribution with low-resolution μCT setups. In this study, we use high-resolution μCT to investigate whether CA4+ accumulates in chondrocytes, and further, to determine whether it affects the low-resolution ex vivo μCT studies of CA4+ stained human AC with varying degree of osteoarthritis. Human osteochondral samples were immersed in three different concentrations of CA4+ (3 mgI/ml, 6 mgI/ml, and 24 mgI/ml and imaged with high-resolution μCT at several timepoints. Different uptake diffusion profiles of CA4+ were observed between the segmented chondrons and the rest of the tissue. While the X-ray -detected CA4+ concentration in chondrons was greater than in the rest of the AC, its contribution to the uptake into the whole tissue was negligible and in line with macro-scale GAG content detected from histology. The efficient uptake of CA4+ into chondrons and surrounding territorial matrix can be explained by the micro-scale distribution of GAG content. CA4+ uptake in chondrons occurred regardless of the progression stage of osteoarthritis

  4. Imaging the Aqueous Humor Outflow Pathway in Human Eyes by Three-dimensional Micro-computed Tomography (3D micro-CT)

    Energy Technology Data Exchange (ETDEWEB)

    C Hann; M Bentley; A Vercnocke; E Ritman; M Fautsch

    2011-12-31

    The site of outflow resistance leading to elevated intraocular pressure in primary open-angle glaucoma is believed to be located in the region of Schlemm's canal inner wall endothelium, its basement membrane and the adjacent juxtacanalicular tissue. Evidence also suggests collector channels and intrascleral vessels may have a role in intraocular pressure in both normal and glaucoma eyes. Traditional imaging modalities limit the ability to view both proximal and distal portions of the trabecular outflow pathway as a single unit. In this study, we examined the effectiveness of three-dimensional micro-computed tomography (3D micro-CT) as a potential method to view the trabecular outflow pathway. Two normal human eyes were used: one immersion fixed in 4% paraformaldehyde and one with anterior chamber perfusion at 10 mmHg followed by perfusion fixation in 4% paraformaldehyde/2% glutaraldehyde. Both eyes were postfixed in 1% osmium tetroxide and scanned with 3D micro-CT at 2 {mu}m or 5 {mu}m voxel resolution. In the immersion fixed eye, 24 collector channels were identified with an average orifice size of 27.5 {+-} 5 {mu}m. In comparison, the perfusion fixed eye had 29 collector channels with a mean orifice size of 40.5 {+-} 13 {mu}m. Collector channels were not evenly dispersed around the circumference of the eye. There was no significant difference in the length of Schlemm's canal in the immersed versus the perfused eye (33.2 versus 35.1 mm). Structures, locations and size measurements identified by 3D micro-CT were confirmed by correlative light microscopy. These findings confirm 3D micro-CT can be used effectively for the non-invasive examination of the trabecular meshwork, Schlemm's canal, collector channels and intrascleral vasculature that comprise the distal outflow pathway. This imaging modality will be useful for non-invasive study of the role of the trabecular outflow pathway as a whole unit.

  5. Long-term Risedronate Treatment Normalizes Mineralization and Continues to Preserve Trabecular Architecture: Sequential Triple Biopsy Studies with Micro-Computed Tomography

    International Nuclear Information System (INIS)

    Borah, B.; Dufresne, T.; Ritman, E.; Jorgensen, S.; Liu, S.; Chmielewski, P.; Phipps, R.; Zhou, X.; Sibonga, J.; Turner, R.

    2006-01-01

    The objective of the study was to assess the time course of changes in bone mineralization and architecture using sequential triple biopsies from women with postmenopausal osteoporosis (PMO) who received long-term treatment with risedronate. Transiliac biopsies were obtained from the same subjects (n = 7) at baseline and after 3 and 5 years of treatment with 5 mg daily risedronate. Mineralization was measured using 3-dimensional (3D) micro-computed tomography (CT) with synchrotron radiation and was compared to levels in healthy premenopausal women (n = 12). Compared to the untreated PMO women at baseline, the premenopausal women had higher average mineralization (Avg-MIN) and peak mineralization (Peak-MIN) by 5.8% (P = 0.003) and 8.0% (P = 0.003), respectively, and lower ratio of low to high-mineralized bone volume (BMR-V) and surface area (BMR-S) by 73.3% (P = 0.005) and 61.7% (P 0.003), respectively. Relative to baseline, 3 years of risedronate treatment significantly increased Avg-MIN (4.9 ± 1.1%, P = 0.016) and Peak-MIN (6.2 ± 1.5%, P = 0.016), and significantly decreased BMR-V (-68.4 ± 7.3%, P = 0.016) and BMR-S (-50.2 ± 5.7%, P = 0.016) in the PMO women. The changes were maintained at the same level when treatment was continued up to 5 years. These results are consistent with the significant reduction of turnover observed after 3 years of treatment and which was similarly maintained through 5 years of treatment. Risedronate restored the degree of mineralization and the ratios of low- to high-mineralized bone to premenopausal levels after 3 years of treatment, suggesting that treatment reduced bone turnover in PMO women to healthy premenopausal levels. Conventional micro-CT analysis further demonstrated that bone volume (BV/TV) and trabecular architecture did not change from baseline up to 5 years of treatment, suggesting that risedronate provided long-term preservation of trabecular architecture in the PMO women. Overall, risedronate provided sustained

  6. Possible Radiation-Induced Damage to the Molecular Structure of Wooden Artifacts Due to Micro-Computed Tomography, Handheld X-Ray Fluorescence, and X-Ray Photoelectron Spectroscopic Techniques

    Directory of Open Access Journals (Sweden)

    Madalena Kozachuk

    2016-05-01

    Full Text Available This study was undertaken to ascertain whether radiation produced by X-ray photoelectron spectroscopy (XPS, micro-computed tomography (μCT and/or portable handheld X-ray fluorescence (XRF equipment might damage wood artifacts during analysis. Changes at the molecular level were monitored by Fourier transform infrared (FTIR analysis. No significant changes in FTIR spectra were observed as a result of μCT or handheld XRF analysis. No substantial changes in the collected FTIR spectra were observed when XPS analytical times on the order of minutes were used. However, XPS analysis collected over tens of hours did produce significant changes in the FTIR spectra.

  7. Comparison of the accuracy of 3-dimensional cone-beam computed tomography and micro-computed tomography reconstructions by using different voxel sizes.

    Science.gov (United States)

    Maret, Delphine; Peters, Ove A; Galibourg, Antoine; Dumoncel, Jean; Esclassan, Rémi; Kahn, Jean-Luc; Sixou, Michel; Telmon, Norbert

    2014-09-01

    Cone-beam computed tomography (CBCT) data are, in principle, metrically exact. However, clinicians need to consider the precision of measurements of dental morphology as well as other hard tissue structures. CBCT spatial resolution, and thus image reconstruction quality, is restricted by the acquisition voxel size. The aim of this study was to assess geometric discrepancies among 3-dimensional CBCT reconstructions relative to the micro-CT reference. A total of 37 permanent teeth from 9 mandibles were scanned with CBCT 9500 and 9000 3D and micro-CT. After semiautomatic segmentation, reconstructions were obtained from CBCT acquisitions (voxel sizes 76, 200, and 300 μm) and from micro-CT (voxel size 41 μm). All reconstructions were positioned in the same plane by image registration. The topography of the geometric discrepancies was displayed by using a color map allowing the maximum differences to be located. The maximum differences were mainly found at the cervical margins and on the cusp tips or incisal edges. Geometric reconstruction discrepancies were significant at 300-μm resolution (P = .01, Wilcoxon test). To study hard tissue morphology, CBCT acquisitions require voxel sizes smaller than 300 μm. This experimental study will have to be complemented by studies in vivo that consider the conditions of clinical practice. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  8. Investigation of a pre-clinical mandibular bone notch defect model in miniature pigs: clinical computed tomography, micro-computed tomography, and histological evaluation.

    Science.gov (United States)

    Carlisle, Patricia L; Guda, Teja; Silliman, David T; Lien, Wen; Hale, Robert G; Brown Baer, Pamela R

    2016-02-01

    To validate a critical-size mandibular bone defect model in miniature pigs. Bilateral notch defects were produced in the mandible of dentally mature miniature pigs. The right mandibular defect remained untreated while the left defect received an autograft. Bone healing was evaluated by computed tomography (CT) at 4 and 16 weeks, and by micro-CT and non-decalcified histology at 16 weeks. In both the untreated and autograft treated groups, mineralized tissue volume was reduced significantly at 4 weeks post-surgery, but was comparable to the pre-surgery levels after 16 weeks. After 16 weeks, CT analysis indicated that significantly greater bone was regenerated in the autograft treated defect than in the untreated defect (P=0.013). Regardless of the treatment, the cortical bone was superior to the defect remodeled over 16 weeks to compensate for the notch defect. The presence of considerable bone healing in both treated and untreated groups suggests that this model is inadequate as a critical-size defect. Despite healing and adaptation, the original bone geometry and quality of the pre-injured mandible was not obtained. On the other hand, this model is justified for evaluating accelerated healing and mitigating the bone remodeling response, which are both important considerations for dental implant restorations.

  9. Shaping ability of the conventional nickel-titanium and reciprocating nickel-titanium file systems: a comparative study using micro-computed tomography.

    Science.gov (United States)

    Hwang, Young-Hye; Bae, Kwang-Shik; Baek, Seung-Ho; Kum, Kee-Yeon; Lee, WooCheol; Shon, Won-Jun; Chang, Seok Woo

    2014-08-01

    This study used micro-computed tomographic imaging to compare the shaping ability of Mtwo (VDW, Munich, Germany), a conventional nickel-titanium file system, and Reciproc (VDW), a reciprocating file system morphologically similar to Mtwo. Root canal shaping was performed on the mesiobuccal and distobuccal canals of extracted maxillary molars. In the RR group (n = 15), Reciproc was used in a reciprocating motion (150° counterclockwise/30° clockwise, 300 rpm); in the MR group, Mtwo was used in a reciprocating motion (150° clockwise/30° counterclockwise, 300 rpm); and in the MC group, Mtwo was used in a continuous rotating motion (300 rpm). Micro-computed tomographic images taken before and after canal shaping were used to analyze canal volume change and the degree of transportation at the cervical, middle, and apical levels. The time required for canal shaping was recorded. Afterward, each file was analyzed using scanning electron microscopy. No statistically significant differences were found among the 3 groups in the time for canal shaping or canal volume change (P > .05). Transportation values of the RR and MR groups were not significantly different at any level. However, the transportation value of the MC group was significantly higher than both the RR and MR groups at the cervical and apical levels (P file deformation was observed for 1 file in group RR (1/15), 3 files in group MR (3/15), and 5 files in group MC (5/15). In terms of shaping ability, Mtwo used in a reciprocating motion was not significantly different from the Reciproc system. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  10. A method for three-dimensional analysis of the root canal system, before and after mechanical instrumentation, using X-ray Micro-computed tomography

    DEFF Research Database (Denmark)

    Markvart, Merete; Bjørndal, Lars; Larsen, Per

    . Extracted molar teeth were embedded in resin and kept moisturized. Each root canal was instrumented with NiTi instruments to #40. The teeth were scanned before and after instrumentation, using a microCT40 micro-tomography (SCANCO Medical AG, Bassersdorf, Switzerland). The reconstructed slices were imported......Clinical studies have shown a connection between the reduction of micro-organisms in the root canal and the degree of apical enlargement. The aim of this study was to create a non-invasive 3D model for monitoring the apical enlargement in molar teeth before and after mechanical instrumentation...

  11. High resolution 3D laboratory x-ray tomography data of femora from young, 1–14 day old C57BL/6 mice

    Directory of Open Access Journals (Sweden)

    Emely L. Bortel

    2015-09-01

    Full Text Available This data article contains high resolution (1.2 µm effective pixel size lab-based micro-computed tomography (µCT reconstructed volume data of the femoral mid-shafts from young C57BL/6 mice. This data formed the basis for the analyses of bone structural development in healthy mice, including closed and open porosity as reported in Bortel et al. [1]. The data reveals changes seen in bone material and porosity distribution observed when mouse bones transform from porous scaffolds into solid structures during normal organogenesis.

  12. Rotary nickel-titanium GT and ProTaper files for root canal shaping by novice operators: a radiographic and micro-computed tomography evaluation.

    Science.gov (United States)

    Gekelman, Diana; Ramamurthy, Ramya; Mirfarsi, Sahar; Paqué, Frank; Peters, Ove A

    2009-11-01

    The purpose of this study was to assess canal preparation outcomes in vitro by novice clinicians after standardized teaching sessions. All students received a training session. In experiment 1, twenty canals of mandibular molars were prepared with GT and ProTaper rotaries by 10 students. Standardized radiographs were exposed before and after canal preparation, and canal curvature was measured; canals were assessed for patency and preparation time. In experiment 2, mandibular molars (20 canals) were submitted to microcomputed tomography before and after canal preparation with ProTaper and GT rotaries by 2 dental students. Canals were metrically assessed for changes (volume, surface, cross-sectional shape, transportation) during canal preparation by using software. In experiment 1, canal curvature decreased by 7.6 degrees and 7.8 degrees for GT and ProTaper preparations; there were no broken instruments, and 2 canals lost patency. The time for GT preparation was longer than for ProTaper (29.7 +/- 6.8 vs 19.4 +/- 8.1 minutes, P session.

  13. Evaluation of apical canal shapes produced sequentially during instrumentation with stainless steel hand and Ni-Ti rotary instruments using Micro-computed tomography

    Directory of Open Access Journals (Sweden)

    Woo-Jin Lee

    2011-05-01

    Full Text Available Objectives The purpose of this study was to determine the optimal master apical file size with minimal transportation and optimal efficiency in removing infected dentin. We evaluated the transportation of the canal center and the change in untouched areas after sequential preparation with a #25 to #40 file using 3 different instruments: stainless steel K-type (SS K-file hand file, ProFile and LightSpeed using microcomputed tomography (MCT. Materials and Methods Thirty extracted human mandibular molars with separated orifices and apical foramens on mesial canals were used. Teeth were randomly divided into three groups: SS K-file, Profile, LightSpeed and the root canals were instrumented using corresponding instruments from #20 to #40. All teeth were scanned with MCT before and after instrumentation. Cross section images were used to evaluate canal transportation and untouched area at 1- , 2- , 3- , and 5- mm level from the apex. Data were statistically analyzed according to' repeated nested design'and Mann-Whitney test (p = 0.05. Results In SS K-file group, canal transportation was significantly increased over #30 instrument. In the ProFile group, canal transportation was significantly increased after preparation with the #40 instrument at the 1- and 2- mm levels. LightSpeed group showed better centering ability than ProFile group after preparation with the #40 instrument at the 1 and 2 mm levels. Conclusions SS K-file, Profile, and LightSpeed showed differences in the degree of apical transportation depending on the size of the master apical file.

  14. A Study of Acute and Chronic Tissue Changes in Surgical and Traumatically-Induced Experimental Models of Knee Joint Injury Using Magnetic Resonance Imaging and Micro-Computed Tomography

    Science.gov (United States)

    Fischenich, Kristine M.; Pauly, Hannah M.; Button, Keith D.; Fajardo, Ryan S.; DeCamp, Charles E.; Haut, Roger C.; Haut Donahue, Tammy L.

    2016-01-01

    Objective The objective of this study was to monitor the progression of joint damage in two animal models of knee joint trauma using two non-invasive, clinically available imaging modalities. Methods A 3-T clinical magnet and micro-computed tomography (mCT) was used to document changes immediately following injury (acute) and post-injury (chronic) at time points of 4, 8, or 12 weeks. Joint damage was recorded at dissection and compared to the chronic magnetic resonance imaging (MRI) record. Fifteen Flemish Giant rabbits were subjected to a single tibiofemoral compressive impact (ACLF), and 18 underwent a combination of anterior cruciate ligament (ACL) and meniscal transection (mACLT). Results All ACLF animals experienced ACL rupture, and 13 also experienced acute meniscal damage. All ACLF and mACLT animals showed meniscal and articular cartilage damages at dissection. Meniscal damage was documented as early as 4 weeks and worsened in 87% of the ACLF animals and 71% of the mACLT animals. Acute cartilage damage also developed further and increased in occurrence with time in both models. A progressive decrease in bone quantity and quality was documented in both models. The MRI data closely aligned with dissection notes suggesting this clinical tool may be a non-invasive method for documenting joint damage in lapine models of knee joint trauma. Conclusions The study investigates the acute to chronic progression of meniscal and cartilage damage at various time points, and chronic changes to the underlying bone in two models of posttraumatic osteoarthritis (PTOA), and highlights the dependency of the model on the location, type, and progression of damage over time. PMID:27756698

  15. Efficacy of CM-Wire, M-Wire, and Nickel-Titanium Instruments for Removing Filling Material from Curved Root Canals: A Micro-Computed Tomography Study.

    Science.gov (United States)

    Rodrigues, Clarissa Teles; Duarte, Marco Antonio Hungaro; de Almeida, Marcela Milanezi; de Andrade, Flaviana Bombarda; Bernardineli, Norberti

    2016-11-01

    The aim of this ex vivo study was to evaluate the removal of filling material after using CM-wire, M-wire, and nickel-titanium instruments in both reciprocating and rotary motions in curved canals. Thirty maxillary lateral incisors were divided into 9 groups according to retreatment procedures: Reciproc R25 followed by Mtwo 40/.04 and ProDesign Logic 50/.01 files; ProDesign R 25/.06 followed by ProDesign Logic 40/.05 and ProDesign Logic 50/.01 files; and Gates-Glidden drills, Hedström files, and K-files up to apical size 30 followed by K-file 40 and K-file 50 up to the working length. Micro-computed tomography scans were performed before and after each reinstrumentation procedure to evaluate root canal filling removal. Statistical analysis was performed with Kruskal-Wallis, Friedman, and Wilcoxon tests (P < .05). No significant differences in filling material removal were found in the 3 groups of teeth. The use of Mtwo and ProDesign Logic 40/.05 rotary files did not enhance filling material removal after the use of reciprocating files. The use of ProDesign Logic 50/.01 files significantly reduced the amount of filling material at the apical levels compared with the use of reciprocating files. Association of reciprocating and rotary files was capable of removing a large amount of filling material in the retreatment of curved canals, irrespective of the type of alloy of the instruments. The use of a ProDesign Logic 50/.01 file for apical preparation significantly reduced the amount of remnant material in the apical portion when compared with reciprocating instruments. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  16. Application of in vivo micro-computed tomography in the temporal characterisation of subchondral bone architecture in a rat model of low-dose monosodium iodoacetate-induced osteoarthritis

    Science.gov (United States)

    2011-01-01

    Introduction Osteoarthritis (OA) is a complex, multifactorial joint disease affecting both the cartilage and the subchondral bone. Animal models of OA aid in the understanding of the pathogenesis of OA and testing suitable drugs for OA treatment. In this study we characterized the temporal changes in the tibial subchondral bone architecture in a rat model of low-dose monosodium iodoacetate (MIA)-induced OA using in vivo micro-computed tomography (CT). Methods Male Wistar rats received a single intra-articular injection of low-dose MIA (0.2 mg) in the right knee joint and sterile saline in the left knee joint. The animals were scanned in vivo by micro-CT at two, six, and ten weeks post-injection, analogous to early, intermediate, and advanced stages of OA, to assess architectural changes in the tibial subchondral bone. The articular cartilage changes in the tibiae were assessed macroscopically and histologically at ten weeks post-injection. Results Interestingly, tibiae of the MIA-injected knees showed significant bone loss at two weeks, followed by increased trabecular thickness and separation at six and ten weeks. The trabecular number was decreased at all time points compared to control tibiae. The tibial subchondral plate thickness of the MIA-injected knee was increased at two and six weeks and the plate porosity was increased at all time points compared to control. At ten weeks, histology revealed loss of proteoglycans, chondrocyte necrosis, chondrocyte clusters, cartilage fibrillation, and delamination in the MIA-injected tibiae, whereas the control tibiae showed no changes. Micro-CT images and histology showed the presence of subchondral bone sclerosis, cysts, and osteophytes. Conclusions These findings demonstrate that the low-dose MIA rat model closely mimics the pathological features of progressive human OA. The low-dose MIA rat model is therefore suitable to study the effect of therapeutic drugs on cartilage and bone in a non-trauma model of OA. In vivo

  17. Manufacturing and application of micro computer for control

    International Nuclear Information System (INIS)

    Park, Seung Man; Heo, Gyeong; Yun, Jun Young

    1990-05-01

    This book deals with machine code and assembly program for micro computer. It composed of 20 chapters, which are micro computer system, practice of a storage cell, manufacturing 1 of micro computer, manufacturing 2 of micro computer, manufacturing of micro computer AID-80A, making of machine language, interface like Z80-PIO and 8255A(PPI), counter and timer interface, exercise of basic command, arithmetic operation, arrangement operation, an indicator control, music playing, detection of input of PIO. control of LED of PIO, PIO mode, CTC control by micro computer, SIO control by micro computer and application by micro computer.

  18. In vitro ceramic scaffold mineralization: comparison between histological and micro-computed topographical analysis

    NARCIS (Netherlands)

    Thimm, B.W.; Wechsler, O.; Bohner, M.; Müller, R.; Hofmann, S.

    2013-01-01

    The porous structure of beta-tricalcium phosphate (b-TCP) scaffolds was assessed by conventional histomor- phometry and micro-computed tomography (micro-CT) to evaluate the substitutability of time-consuming histomor- phometry by rapid micro-CT. Extracellular matrix mineral- ization on human

  19. 'Micro-8' micro-computer system

    International Nuclear Information System (INIS)

    Yagi, Hideyuki; Nakahara, Yoshinori; Yamada, Takayuki; Takeuchi, Norio; Koyama, Kinji

    1978-08-01

    The micro-computer Micro-8 system has been developed to organize a data exchange network between various instruments and a computer group including a large computer system. Used for packet exchangers and terminal controllers, the system consists of ten kinds of standard boards including a CPU board with INTEL-8080 one-chip-processor. CPU architecture, BUS architecture, interrupt control, and standard-boards function are explained in circuit block diagrams. Operations of the basic I/O device, digital I/O board and communication adapter are described with definitions of the interrupt ramp status, I/O command, I/O mask, data register, etc. In the appendixes are circuit drawings, INTEL-8080 micro-processor specifications, BUS connections, I/O address mappings, jumper connections of address selection, and interface connections. (author)

  20. Biocompatibility property of 100% strontium-substituted SiO2 -Al2 O3 -P2 O5 -CaO-CaF2 glass ceramics over 26 weeks implantation in rabbit model: Histology and micro-Computed Tomography analysis.

    Science.gov (United States)

    Basu, Bikramjit; Sabareeswaran, A; Shenoy, S J

    2015-08-01

    One of the desired properties for any new biomaterial composition is its long-term stability in a suitable animal model and such property cannot be appropriately assessed by performing short-term implantation studies. While hydroxyapatite (HA) or bioglass coated metallic biomaterials are being investigated for in vivo biocompatibility properties, such study is not extensively being pursued for bulk glass ceramics. In view of their inherent brittle nature, the implant stability as well as impact of long-term release of metallic ions on bone regeneration have been a major concern. In this perspective, the present article reports the results of the in vivo implantation experiments carried out using 100% strontium (Sr)-substituted glass ceramics with the nominal composition of 4.5 SiO2 -3Al2 O3 -1.5P2 O5 -3SrO-2SrF2 for 26 weeks in cylindrical bone defects in rabbit model. The combination of histological and micro-computed tomography analysis provided a qualitative and quantitative understanding of the bone regeneration around the glass ceramic implants in comparison to the highly bioactive HA bioglass implants (control). The sequential polychrome labeling of bone during in vivo osseointegration using three fluorochromes followed by fluorescence microscopy observation confirmed homogeneous bone formation around the test implants. The results of the present study unequivocally confirm the long-term implant stability as well as osteoconductive property of 100% Sr-substituted glass ceramics, which is comparable to that of a known bioactive implant, that is, HA-based bioglass. © 2014 Wiley Periodicals, Inc.

  1. Using a micro computer based test bank

    International Nuclear Information System (INIS)

    Hamel, R.T.

    1987-01-01

    Utilizing a micro computer based test bank offers a training department many advantages and can have a positive impact upon training procedures and examination standards. Prior to data entry, Training Department management must pre-review the examination questions and answers to ensure compliance with examination standards and to verify the validity of all questions. Management must adhere to the TSD format since all questions require an enabling objective numbering scheme. Each question is entered under the enabling objective upon which it is based. Then the question is selected via the enabling objective. This eliminates any instructor bias because a random number generator chooses the test question. However, the instructor may load specific questions to create an emphasis theme for any test. The examination, answer and cover sheets are produced and printed within minutes. The test bank eliminates the large amount of time that is normally required for an instructor to formulate an examination. The need for clerical support is reduced by the elimination of typing examinations and also by the software's ability to maintain and generate student/course lists, attendance sheets, and grades. Software security measures limit access to the test bank, and the impromptu method used to generate and print an examination enhance its security

  2. Micro-computer control for super-critical He generation

    International Nuclear Information System (INIS)

    Tamada, Noriharu; Sekine, Takehiro; Tomiyama, Sakutaro

    1979-01-01

    The development of a large scale refrigeration system is being stimulated by new superconducting techniques representated by a superconducting power cable and a magnet. For the practical operation of such a large system, an automatic control system with a computer is required, because it can attain an effective and systematic operation. For this reason, we examined and developed micro-computer control techniques for supercritical He generation, as a simplified control model of the refrigeration system. The experimental results showed that the computer control system can attain fine controlability, even if the control element is only one magnetic valve, but a BASIK program language of micro-computer, which is convinient and generaly used, isn't enough one to control a more complicated system, because of its low calculating speed. Then we conclude that a more effective program language for micro-computer must be developed to realize practical refrigeration control. (author)

  3. Reactor protection system design using micro-computers

    International Nuclear Information System (INIS)

    Fairbrother, D.B.

    1976-01-01

    Reactor protection systems for nuclear power plants have traditionally been built using analog hardware. This hardware works quite well for single parameter trip functions; however, optimum protection against DNBR and KW/ft limits requires more complex trip functions than can easily be handled with analog hardware. For this reason, Babcock and Wilcox has introduced a Reactor Protection System, called the RPS-II, that utilizes a micro-computer to handle the more complex trip functions. The paper describes the design of the RPS-II and the operation of the micro-computer within the Reactor Protection System

  4. Reactor protection system design using micro-computers

    International Nuclear Information System (INIS)

    Fairbrother, D.B.

    1977-01-01

    Reactor Protection Systems for Nuclear Power Plants have traditionally been built using analog hardware. This hardware works quite well for single parameter trip functions; however, optimum protection against DNBR and KW/ft limits requires more complex trip functions than can easily be handled with analog hardware. For this reason, Babcock and Wilcox has introduced a Reactor Protection System, called the RPS-II, that utilizes a micro-computer to handle the more complex trip functions. This paper describes the design of the RPS-II and the operation of the micro-computer within the Reactor Protection System

  5. Micro-computer cards for hard industrial environment

    Energy Technology Data Exchange (ETDEWEB)

    Breton, J M

    1984-03-15

    Approximately 60% of present or future distributed systems have, or will have, operational units installed in hard environments. In these applications, which include canalization and industrial motor control, robotics and process control, systems must be easily applied in environments not made for electronic use. The development of card systems in this hard industrial environment, which is found in petrochemical industry and mines is described. National semiconductor CIM card system CMOS technology allows the real time micro computer application to be efficient and functional in hard industrial environments.

  6. The development and application of a coincidence measurement apparatus with micro-computer system

    International Nuclear Information System (INIS)

    Du Hongshan; Zhou Youpu; Gao Junlin; Qin Deming; Cao Yunzheng; Zhao Shiping

    1987-01-01

    A coincidence measurement apparatus with micro-computer system is developed. Automatic data acquisition and processing are achieved. Results of its application for radioactive measurement are satisfactory

  7. Gamma dose effects valuation on micro computing components

    International Nuclear Information System (INIS)

    Joffre, F.

    1995-01-01

    Robotics in hostile environment raises the problem of micro computing components resistance with gamma radiation cumulated dose. The current aim is to reach a dose of 3000 grays with industrial components. A methodology and an instrumentation adapted to test this type of components have been developed. The aim of this work is to present the advantages and disadvantages bound to the use of industrial components in the presence of gamma radiation. After an analysis of the criteria allowing to justify the technological choices, the different steps which characterize the selection and the assessment methodology used are explained. The irradiation and measures means now operational are mentioned. Moreover, the supply aspects of the chosen components for the design of an industrialized system is taken into account. These selection and assessment components contribute to the development and design of computers for civil nuclear robotics. (O.M.)

  8. Serial non-invasive assessment of antibody induced nephritis in mice using positron emission tomography.

    Directory of Open Access Journals (Sweden)

    Guiyang Hao

    Full Text Available Mouse models of experimental anti-glomerular basement membrane (anti-GBM nephritis provide an analytical tool for studying spontaneous lupus nephritis. The potential of Positron Emission Tomography (PET was evaluated using 2-deoxy-2-[(18F]fluoro-d-glucose (FDG as a probe to monitor the progression of anti-GBM induced nephritis in a mouse model. The imaging results were compared to conventional measures of renal function and pathological changes. Serum and urinary vascular cell adhesion molecule-1 (VCAM-1 levels were used as measures of endothelial cell activation and inflammation. Following a challenge with anti-glomerular antibodies, mice exhibited peak changes in serum creatinine, proteinuria, and glomerulonephritis score at 14 days post-challenge (p.c.. In contrast, VCAM levels peaked at day 7 p.c. On dynamic PET images (0-60 min of day 7, kidneys of the anti-GBM nephritis mice demonstrated a unique pattern of FDG uptake. Compared to the time activity curve (TAC prior to challenge, a rightward shift was observed after the challenge. By day 10 p.c., kidney FDG uptake was lower than baseline and remained so until the study ended at 21 days p.c. During this time frame measures of renal dysfunction remained high but VCAM-1 levels declined. These changes were accompanied by an increase in kidney volume as measured by Computed Tomography (CT and intra-abdominal fluid collection. Our results suggest that FDG-PET-CT can be used as a non-invasive imaging tool to longitudinally monitor the progression of renal disease activity in antibody mediated nephritis and the magnitude of renal FDG retention correlates better with early markers of renal inflammation than renal dysfunction.

  9. Detection of oral early cancerous lesion by using polarization-sensitive optical coherence tomography: mice model

    Science.gov (United States)

    Lee, Hong-Yi; Chen, Ping-Hsien; Lee, Tzu-Han; Chang, Kuo-Wei; Kuo, Wen-Chuan

    2018-02-01

    Oral cancer is the 11th most common cancer worldwide, especially in a male adult. The median age of death in oral cancer was 55 years, 10-20 years earlier than other cancers. Presently, oral cancer is often found in late stage, because the lesion is often flat in early stage and is difficult to diagnose under traditional white light imaging. The only definitive method for determining cancer is an invasive biopsy and then using histology examination. How to detect precancerous lesions or early malignant lesions is an important issue for improving prognosis of oral cancer. Optical coherence tomography (OCT) is a new optical tool for diagnosing early malignant lesions in the skin or gastrointestinal tract recently. Here we report a new method for detecting precancerous or early malignant oral lesions by using swept source polarization-sensitive optical coherence tomography (PS-OCT) with center-wavelength 1310 nm, bandwidth 110 nm and 100 kHz swept rate. We used all single-mode fiber design to detect the change of birefringence information in the epithelium structure. This system has an advantage that enables measurement of backscattered intensity and birefringence simultaneously with only one A-scan per transverse location. In preliminary result, we computed the slope of the every A-scan signal in tissue part using a linear-curve fitting in backscattered intensity and birefringence on the enface. In this research, we used an oral cancer mice model for observing the change of structure and birefringence properties in different stages of oral cancer mice. We presented the parametric enface imaging that can detect the early oral malignant lesions.

  10. Tomography

    International Nuclear Information System (INIS)

    1985-01-01

    Already widely accepted in medicine, tomography can also be useful in industry. The theory behind tomography and a demonstration of the technique to inspect a motorcycle carburetor is presented. To demonstrate the potential of computer assisted tomography (CAT) to accurately locate defects in three dimensions, a sectioned 5 cm gate valve with a shrink cavity made visible by the sectioning was tomographically imaged using a Co-60 source. The tomographic images revealed a larger cavity below the sectioned surface. The position of this cavity was located with an in-plane and axial precision of approximately +-1 mm. The volume of the cavity was estimated to be approximately 40 mm 3

  11. Telomerase-Deficient Mice Exhibit Bone Loss Owing to Defects in Osteoblasts and Increased Osteoclastogenesis by Inflammatory Microenvironment

    DEFF Research Database (Denmark)

    Saeed, H.; Abdallah, B. M.; Ditzel, N.

    2011-01-01

    Telomere shortening owing to telomerase deficiency leads to accelerated senescence of human skeletal (mesenchymal) stem cells (MSCs) in vitro, whereas overexpression leads to telomere elongation, extended life span, and enhanced bone formation. To study the role of telomere shortening in vivo, we...... studied the phenotype of telomerase-deficient mice (Terc(-/-)).Terc(-/-) mice exhibited accelerated age-related bone loss starting at 3 months of age and during 12 months of follow-up revealed by dual-energy X-ray absorptiometric (DXA) scanning and by micro-computed tomography (mu CT). Bone...... histomorphometry revealed decreased mineralized surface and bone-formation rate as well as increased osteoclast number and size in Terc(-/-) mice. Also, serum total deoxypyridinoline (tDPD) was increased in Terc(-/-) mice. MSCs and osteoprogenitors isolated from Terc(-l-) mice exhibited intrinsic defects...

  12. Tomography

    International Nuclear Information System (INIS)

    Barrett, H.H.; Gordon, S.; Swindell, W.

    1980-01-01

    Apparatus is described for generating a two-dimensional back-projected image of a slice of an object in tomography. The apparatus uses optical techniques to perform the functions of filtering and back projection. Central to the technique is a cylindrical drum which rotates at a fast rate and whose rotational axis tilts at a slower rate. The novel method overcomes the problem of image blurring due to motion which occurs in many tomographic techniques. It also has the advantages of being less expensive and simpler compared to tomography using digital processing techniques which require fast computers. (UK)

  13. Integrating Micro-computers with a Centralized DBMS: ORACLE, SEED AND INGRES

    Science.gov (United States)

    Hoerger, J.

    1984-01-01

    Users of ADABAS, a relational-like data base management system (ADABAS) with its data base programming language (NATURAL) are acquiring microcomputers with hopes of solving their individual word processing, office automation, decision support, and simple data processing problems. As processor speeds, memory sizes, and disk storage capacities increase, individual departments begin to maintain "their own" data base on "their own" micro-computer. This situation can adversely affect several of the primary goals set for implementing a centralized DBMS. In order to avoid this potential problem, these micro-computers must be integrated with the centralized DBMS. An easy to use and flexible means for transferring logic data base files between the central data base machine and micro-computers must be provided. Some of the problems encounted in an effort to accomplish this integration and possible solutions are discussed.

  14. A full automatic system controlled with IBM-PC/XT micro-computer for neutron activation analysis

    International Nuclear Information System (INIS)

    Song Quanxun

    1992-01-01

    A full automatic system controlled with micro-computers for NAA is described. All processes are automatically completed with an IBM-PC/XT micro-computer. The device is stable, reliable, flexible and convenient for use and has many functions and applications in automatical analysis of long, middle and short lived nuclides. Due to a high working efficiency of the instrument and micro-computers, both time and power can be saved. This method can be applied in other nuclear analysis techniques

  15. Tomography

    International Nuclear Information System (INIS)

    Allan, C.J.; Keller, N.A.; Lupton, L.R.; Taylor, T.; Tonner, P.D.

    1984-10-01

    Tomography is a non-intrusive imaging technique being developed at CRNL as an industrial tool for generating quantitative cross-sectional density maps of objects. Of most interest is tomography's ability to: distinguish features within complex geometries where other NDT techniques fail because of the complexity of the geometry; detect/locate small density changes/defects within objects, e.g. void fraction measurements within thick-walled vessels, shrink cavities in castings, etc.; provide quantitative data that can be used in analyses, e.g. of complex processes, or fracture mechanics; and provide objective quantitative data that can be used for (computer-based) quality assurance decisions, thereby reducing and in some cases eliminating the present subjectivity often encountered in NDT. The CRNL program is reviewed and examples are presented to illustrate the potential and the limitations of the technology

  16. Micro-computed tomography (CT) based assessment of dental regenerative therapy in the canine mandible model

    Science.gov (United States)

    Khobragade, P.; Jain, A.; Setlur Nagesh, S. V.; Andreana, S.; Dziak, R.; Sunkara, S. K.; Sunkara, S.; Bednarek, D. R.; Rudin, S.; Ionita, C. N.

    2015-03-01

    High-resolution 3D bone-tissue structure measurements may provide information critical to the understanding of the bone regeneration processes and to the bone strength assessment. Tissue engineering studies rely on such nondestructive measurements to monitor bone graft regeneration area. In this study, we measured bone yield, fractal dimension and trabecular thickness through micro-CT slices for different grafts and controls. Eight canines underwent surgery to remove a bone volume (defect) in the canine's jaw at a total of 44 different locations. We kept 11 defects empty for control and filled the remaining ones with three regenerative materials; NanoGen (NG), a FDA-approved material (n=11), a novel NanoCalcium Sulfate (NCS) material (n=11) and NCS alginate (NCS+alg) material (n=11). After a minimum of four and eight weeks, the canines were sacrificed and the jaw samples were extracted. We used a custombuilt micro-CT system to acquire the data volume and developed software to measure the bone yield, fractal dimension and trabecular thickness. The software used a segmentation algorithm based on histograms derived from volumes of interest indicated by the operator. Using bone yield and fractal dimension as indices we are able to differentiate between the control and regenerative material (p<0.005). Regenerative material NCS showed an average 63.15% bone yield improvement over the control sample, NCS+alg showed 55.55% and NanoGen showed 37.5%. The bone regeneration process and quality of bone were dependent upon the position of defect and time period of healing. This study presents one of the first quantitative comparisons using non-destructive Micro-CT analysis for bone regenerative material in a large animal with a critical defect model. Our results indicate that Micro-CT measurement could be used to monitor invivo bone regeneration studies for greater regenerative process understanding.

  17. Innervation of the cow's inner ear derived from micro-computed tomography

    Science.gov (United States)

    Costeur, Loic; Mennecart, Bastien; Khimchenko, Anna; Müller, Bert; Schulz, Georg

    2017-09-01

    The innervation of the inner ear has been thoroughly investigated in humans and in some animal models such as the guinea pig, the rabbit, the cat, the dog, the rat, the pig and some monkeys. Ruminant inner ears are still poorly known and their innervation was never investigated despite its potential interest in phylogenetic reconstructions. Following earlier works on the ontogeny of the cow's ear, we expand our understanding of this structure by reconstructing the fine innervation pattern of the inner ear of the cow in two ontogenetic stages, at 7 months gestation and at an adult age. Since we work on dry skeletal specimens, only the endocast of the innervation inside the petrosal bone was reconstructed up to the internal acoustic meatus. The paths of the facial and vestibulocochlear nerves could be reconstructed together with that of the spiral ganglion canal. The nerves have a very fibrous pattern. The bony cavities of the ampular and utricular branches of the vestibulocochlear nerve could also be reconstructed. Our observations confirm that not all bony structures are present in foetal stages since the branch of cranial nerve VII is not visible on the foetus but very broad on the adult stage. The fibrous pattern within the modiolus connecting the spiral canal to the cochlear nerve is also less dense than in the adult stage. The shape of the branch of cranial nerve VII is very broad in the cow ending in a large hiatus Fallopii; this, together with the above-mentioned particularities, could constitute relevant observations for phylogenetical purposes when more data will be made available.

  18. Retention assessment of magnetic nanoparticles in rat arteries with micro-computed tomography.

    Science.gov (United States)

    Tu, Shu-Ju; Wu, Siao-Yun; Wang, Fu-Sheng; Ma, Yunn-Hwa

    2014-03-07

    Magnetic nanoparticles (MNPs) may serve as carriers for pharmacological agents to the target in a magnetic-force guiding system. It is essential to achieve effective retention of MNPs through the external magnet placement. However, it is difficult to estimate the retention efficiency of MNPs and validate the experimental strategies. Micro-CT was used to identify the spatial distribution of MNP retention and image analysis is then extended to evaluate the MNP delivery efficiency. Male Sprague Dawley rats were anesthetized to expose abdominal arteries with an NdFeB magnet of 4.9 kG placed by the left iliac artery. After a 20 min equilibrium period, arteries were ligated, removed and fixed in a paraformaldehyde solution. Experiments were performed with intravenous injection in our platform with two independent groups. MNPs were used in the first group, while chemical compounds of recombinant tissue plaminogen activator were attached to MNPs as rtPA (recombinant tissue plaminogen activator)-MNPs in the second group. Image analysis of micro-CT shows the average retention volume of MNPs and rtPA-MNPs in the left iliac arteries is 9.3 and 6.3 fold of that in the right. Large local aggregation of MNPs and rtPA-MNPs in the left iliac arteries is the consequence of external magnet placement, suggesting feasibility of magnetic targeting through the intravenous administration. We also determined that on average 0.57% and 0.064% of MNPs and rtPA-MNPs respectively were retained in the left iliac artery. It was estimated that the average rtPA concentration of 60.16 µg mL(-1) may be achieved with rtPA-MNPs. With the micro-CT imaging approach, we accomplished visualization of the aggregation of retained particles; reconstructed 3D distribution of relative retention; estimated the average particle number of local retention; determined efficiency of targeted delivery. In particular, our quantitative image assessment suggests that intravenous administration of rtPA-MNPs may retain local concentration of rtPA high enough to induce thrombolysis.

  19. Contrast Agents for Micro-Computed Tomography of Microdamage in Bone

    National Research Council Canada - National Science Library

    Roeder, Ryan K

    2008-01-01

    ...) and contrast agents with higher x-ray attenuation than bone. The ability to detect the presence and to a limited extent the morphology of microdamage in cortical and trabecular bone using micro-CT was demonstrated using a barium sulfate (BaSO4) stain...

  20. Modeling of the Tension and Compression Behavior of Sintered 316L Using Micro Computed Tomography

    Directory of Open Access Journals (Sweden)

    Doroszko Michał

    2015-06-01

    Full Text Available This paper describes the method of numerical modeling of the tension and compression behavior of sintered 316L. In order to take into account the shape of the mesostructures of materials in the numerical modeling, X-ray microtomography was used. Based on the micro-CT images, three-dimensional geometrical models mapped shapes of the porosity were generated. To the numerical calculations was used finite element method. Based on the received stress and strain fields was described the mechanism of deformation of the materials until fracture. The influence of material discontinuities at the mesoscopic scale on macromechanical properties of the porous materials was investigated.

  1. Contrast Agents for Micro-Computed Tomography of Microdamage in Bone

    Science.gov (United States)

    2011-01-01

    However, cracks in the enamel were readily detected by micro-CT both with and without the use of a con- trast agent (Fig. 2(b)) due to the relatively low x...ray attenua- tion of the fluid space in the crack compared to the enamel . Therefore, the main limitation of the difficulty distinguishing BaSO4 from...Roeder, 2011). Moreover, cracks in whole human molars were also imaged by contrast-enhanced micro-CT (Appendix 5, Landrigan et al., 2010). KEY

  2. Morphology of Major Stone Types, As Shown by Micro Computed Tomography (micro CT)

    International Nuclear Information System (INIS)

    Jackson, Molly E.; Beuschel, Christian A.; McAteer, James A.; Williams, James C.

    2008-01-01

    Micro CT offers the possibility of providing a non-destructive method of stone analysis that allows visualization of 100% of the stone's volume. For the present study, micro CT analysis was completed on stones of known composition with isotropic voxel sizes of either 7 or 9.1 μm. Each mineral type was distinctive, either by x-ray attenuation values or by morphology. Minor components, such as the presence of apatite in oxalate stones, were easily seen. The analysis of stones by micro CT opens up the possibility of exploring the stone as an encapsulated history of the patient's disease, showing changes in mineral deposition with time.

  3. Quantification of skeletal growth, modeling, and remodeling by in vivo micro computed tomography.

    Science.gov (United States)

    Altman, Allison R; Tseng, Wei-Ju; de Bakker, Chantal M J; Chandra, Abhishek; Lan, Shenghui; Huh, Beom Kang; Luo, Shiming; Leonard, Mary B; Qin, Ling; Liu, X Sherry

    2015-12-01

    In this study we established an image analysis scheme for the investigation of cortical and trabecular bone development during skeletal growth and tested this concept on in vivo μCT images of rats. To evaluate its efficacy, we applied the technique to young (1-month-old) and adult (3-month-old) rat tibiae with vehicle (Veh) or intermittent parathyroid hormone (PTH) treatment. By overlaying 2 sequential scans based on their distinct trabecular microarchitecture, we calculated the linear growth rate of young rats to be 0.31 mm/day at the proximal tibia. Due to rapid growth (3.7 mm in 12 days), the scanned bone region at day 12 had no overlap with the bone tissue scanned at day 0. Instead, the imaged bone region at day 12 represented newly generated bone tissue from the growth plate. The new bone of the PTH-treated rats had significantly greater trabecular bone volume fraction, number, and thickness than those of the Veh-treated rats, indicating PTH's anabolic effect on bone modeling. In contrast, the effect of PTH on adult rat trabecular bone was found to be caused by PTH's anabolic effect on bone remodeling. The cortical bone at the proximal tibia of young rats also thickened more in the PTH group (23%) than the Veh group (14%). This was primarily driven by endosteal bone formation and coalescence of trabecular bone into the cortex. This process can be visualized by aligning the local bone structural changes using image registration. As a result, the cortex after PTH treatment was 31% less porous, and had a 22% greater polar moment of inertia compared to the Veh group. Lastly, we monitored the longitudinal bone growth in adult rats by measuring the distance of bone flow away from the proximal tibial growth plate from 3 months to 19 months of age and discovered a total of 3.5mm growth in 16 months. It was demonstrated that this image analysis scheme can efficiently evaluate bone growth, bone modeling, and bone remodeling, and is ready to be translated into a clinical imaging platform. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Noninvasive Imaging of Retinal Morphology and Microvasculature in Obese Mice Using Optical Coherence Tomography and Optical Microangiography

    Science.gov (United States)

    Zhi, Zhongwei; Chao, Jennifer R.; Wietecha, Tomasz; Hudkins, Kelly L.; Alpers, Charles E.; Wang, Ruikang K.

    2014-01-01

    Purpose. To evaluate early diabetes-induced changes in retinal thickness and microvasculature in a type 2 diabetic mouse model by using optical coherence tomography (OCT)/optical microangiography (OMAG). Methods. Twenty-two-week-old obese (OB) BTBR mice (n = 10) and wild-type (WT) control mice (n = 10) were imaged. Three-dimensional (3D) data volumes were captured with spectral domain OCT using an ultrahigh-sensitive OMAG scanning protocol for 3D volumetric angiography of the retina and dense A-scan protocol for measurement of the total retinal blood flow (RBF) rate. The thicknesses of the nerve fiber layer (NFL) and that of the NFL to the inner plexiform layer (IPL) were measured and compared between OB and WT mice. The linear capillary densities within intermediate and deep capillary layers were determined by the number of capillaries crossing a 500-μm line. The RBF rate was evaluated using an en face Doppler approach. These quantitative measurements were compared between OB and WT mice. Results. The retinal thickness of the NFL to IPL was significantly reduced in OB mice (P < 0.01) compared to that in WT mice, whereas the NFL thickness between the two was unchanged. 3D depth-resolved OMAG angiography revealed the first in vivo 3D model of mouse retinal microcirculation. Although no obvious differences in capillary vessel densities of the intermediate and deep capillary layers were detected between normal and OB mice, the total RBF rate was significantly lower (P < 0.05) in OB mice than in WT mice. Conclusions. We conclude that OB BTBR mice have significantly reduced NFL–IPL thicknesses and total RBF rates compared with those of WT mice, as imaged by OCT/OMAG. OMAG provides an unprecedented capability for high-resolution depth-resolved imaging of mouse retinal vessels and blood flow that may play a pivotal role in providing a noninvasive method for detecting early microvascular changes in patients with diabetic retinopathy. PMID:24458155

  5. Semi-automatic classification of skeletal morphology in genetically altered mice using flat-panel volume computed tomography.

    Directory of Open Access Journals (Sweden)

    Christian Dullin

    2007-07-01

    Full Text Available Rapid progress in exploring the human and mouse genome has resulted in the generation of a multitude of mouse models to study gene functions in their biological context. However, effective screening methods that allow rapid noninvasive phenotyping of transgenic and knockout mice are still lacking. To identify murine models with bone alterations in vivo, we used flat-panel volume computed tomography (fpVCT for high-resolution 3-D imaging and developed an algorithm with a computational intelligence system. First, we tested the accuracy and reliability of this approach by imaging discoidin domain receptor 2- (DDR2- deficient mice, which display distinct skull abnormalities as shown by comparative landmark-based analysis. High-contrast fpVCT data of the skull with 200 microm isotropic resolution and 8-s scan time allowed segmentation and computation of significant shape features as well as visualization of morphological differences. The application of a trained artificial neuronal network to these datasets permitted a semi-automatic and highly accurate phenotype classification of DDR2-deficient compared to C57BL/6 wild-type mice. Even heterozygous DDR2 mice with only subtle phenotypic alterations were correctly determined by fpVCT imaging and identified as a new class. In addition, we successfully applied the algorithm to classify knockout mice lacking the DDR1 gene with no apparent skull deformities. Thus, this new method seems to be a potential tool to identify novel mouse phenotypes with skull changes from transgenic and knockout mice on the basis of random mutagenesis as well as from genetic models. However for this purpose, new neuronal networks have to be created and trained. In summary, the combination of fpVCT images with artificial neuronal networks provides a reliable, novel method for rapid, cost-effective, and noninvasive primary screening tool to detect skeletal phenotypes in mice.

  6. Multi-scale X-ray computed tomography to detect and localize metal-based nanomaterials in lung tissues of in vivo exposed mice.

    Science.gov (United States)

    Chaurand, Perrine; Liu, Wei; Borschneck, Daniel; Levard, Clément; Auffan, Mélanie; Paul, Emmanuel; Collin, Blanche; Kieffer, Isabelle; Lanone, Sophie; Rose, Jérôme; Perrin, Jeanne

    2018-03-13

    In this methodological study, we demonstrated the relevance of 3D imaging performed at various scales for the ex vivo detection and location of cerium oxide nanomaterials (CeO 2 -NMs) in mouse lung. X-ray micro-computed tomography (micro-CT) with a voxel size from 14 µm to 1 µm (micro-CT) was combined with X-ray nano-computed tomography with a voxel size of 63 nm (nano-CT). An optimized protocol was proposed to facilitate the sample preparation, to minimize the experimental artifacts and to optimize the contrast of soft tissues exposed to metal-based nanomaterials (NMs). 3D imaging of the NMs biodistribution in lung tissues was consolidated by combining a vast variety of techniques in a correlative approach: histological observations, 2D chemical mapping and speciation analysis were performed for an unambiguous detection of NMs. This original methodological approach was developed following a worst-case scenario of exposure, i.e. high dose of exposure with administration via intra-tracheal instillation. Results highlighted both (i) the non-uniform distribution of CeO 2 -NMs within the entire lung lobe (using large field-of-view micro-CT) and (ii) the detection of CeO 2 -NMs down to the individual cell scale, e.g. macrophage scale (using nano-CT with a voxel size of 63 nm).

  7. JAX: a micro-computer based X-ray diffractometer controller

    International Nuclear Information System (INIS)

    Naval, P.C. Jr.

    1987-05-01

    This paper describes a micro-computer based X-ray diffractometer controller and explores its possibilities in simplifying acquisition and analysis of X-ray powder diffraction data. The interrupt-driven controller can operate in both present time and present count data acquisition modes and allows a data analysis program to execute concurrently with data collection. (Auth.). 16 figs.; 2 tabs

  8. Data processing with PC-9801 micro-computer for HCN laser scattering experiments

    International Nuclear Information System (INIS)

    Iwasaki, T.; Okajima, S.; Kawahata, K.; Tetsuka, T.; Fujita, J.

    1986-09-01

    In order to process the data of HCN laser scattering experiments, a micro-computer software has been developed and applied to the measurements of density fluctuations in the JIPP T-IIU tokamak plasma. The data processing system consists of a spectrum analyzer, SM-2100A Signal Analyzer (IWATSU ELECTRIC CO., LTD.), PC-9801m3 micro-computer, a CRT-display and a dot-printer. The output signals from the spectrum analyzer are A/D converted, and stored on a mini-floppy-disk equipped to the signal analyzer. The software to process the data is composed of system-programs and several user-programs. The real time data processing is carried out for every shot of plasma at 4 minutes interval by the micro-computer connected with the signal analyzer through a GP-IB interface. The time evolutions of the frequency spectrum of the density fluctuations are displayed on the CRT attached to the micro-computer and printed out on a printer-sheet. In the case of the data processing after experiments, the data stored on the floppy-disk of the signal analyzer are read out by using a floppy-disk unit attached to the micro-computer. After computation with the user-programs, the results, such as monitored signal, frequency spectra, wave number spectra and the time evolutions of the spectrum, are displayed and printed out. In this technical report, the system, the software and the directions for use are described. (author)

  9. Hand and nickel-titanium root canal instrumentation performed by dental students: a micro-computed tomographic study.

    Science.gov (United States)

    Peru, M; Peru, C; Mannocci, F; Sherriff, M; Buchanan, L S; Pitt Ford, T R

    2006-02-01

    The aim of this study was to evaluate root canals instrumented by dental students using the modified double-flared technique, nickel-titanium (NiTi) rotary System GT files and NiTi rotary ProTaper files by micro-computed tomography (MCT). A total of 36 root canals from 18 mesial roots of mandibular molar teeth were prepared; 12 canals were prepared with the modified double-flared technique, using K-flexofiles and Gates-Glidden burs; 12 canals were prepared using System GT and 12 using ProTaper rotary files. Each root was scanned using MCT preoperatively and postoperatively. At the coronal and mid-root sections, System GT and ProTaper files produced significantly less enlarged canal cross-sectional area, volume and perimeter than the modified double-flared technique (P ProTaper (P ProTaper and System GT were able to prepare root canals with little or no procedural error compared with the modified double-flared technique. Under the conditions of this study, inexperienced dental students were able to prepare curved root canals with rotary files with greater preservation of tooth structure, low risk of procedural errors and much quicker than with hand instruments.

  10. Micro-computed tomographic comparison of nickel-titanium rotary versus traditional instruments in C-shaped root canal system.

    Science.gov (United States)

    Yin, Xingzhe; Cheung, Gary Shun-Pan; Zhang, Chengfei; Masuda, Yoshiko Murakami; Kimura, Yuichi; Matsumoto, Koukichi

    2010-04-01

    The purpose of this study was to assess the efficacy of instrumentation of C-shaped canals with ProTaper rotary system and traditional instruments by using micro-computed tomography (micro-CT). Twenty-four mandibular molars with C-shaped canals were selected in pairs and sorted equally into 2 groups, which were assigned for instrumentation by ProTaper rotary system (ProTaper group) or by K-files and Gates-Glidden burs (Hand Instrument group). Three-dimensional images were constructed by micro-CT. The volume of dentin removed, uninstrumented canal area, time taken for instrumentation, and iatrogenic error of instrumentation were investigated. Hand Instrument group showed greater amount of volumetric dentin removal and left less uninstrumented canal area than ProTaper group (P ProTaper group than for Hand Instrument group (P Hand Instrument group than for ProTaper group. It was concluded that ProTaper rotary system maintained the canal curvature with speediness and few procedural errors, whereas traditional instrumentation can clean more canal surface. Copyright (c) 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  11. Quantitative ex-vivo micro-computed tomographic imaging of blood vessels and necrotic regions within tumors.

    Science.gov (United States)

    Downey, Charlene M; Singla, Arvind K; Villemaire, Michelle L; Buie, Helen R; Boyd, Steven K; Jirik, Frank R

    2012-01-01

    Techniques for visualizing and quantifying the microvasculature of tumors are essential not only for studying angiogenic processes but also for monitoring the effects of anti-angiogenic treatments. Given the relatively limited information that can be gleaned from conventional 2-D histological analyses, there has been considerable interest in methods that enable the 3-D assessment of the vasculature. To this end, we employed a polymerizing intravascular contrast medium (Microfil) and micro-computed tomography (micro-CT) in combination with a maximal spheres direct 3-D analysis method to visualize and quantify ex-vivo vessel structural features, and to define regions of hypoperfusion within tumors that would be indicative of necrosis. Employing these techniques we quantified the effects of a vascular disrupting agent on the tumor vasculature. The methods described herein for quantifying whole tumor vascularity represent a significant advance in the 3-D study of tumor angiogenesis and evaluation of novel therapeutics, and will also find potential application in other fields where quantification of blood vessel structure and necrosis are important outcome parameters.

  12. Tomography

    International Nuclear Information System (INIS)

    Brown, B.H.; Barber, D.C.; Freeston, I.L.

    1983-01-01

    Tomography images of a body are constructed by placing a plurality of surface electrodes at spaced intervals on the body, causing currents to flow in the body (e.g. by applying a potential between each pair of electrodes in turn, or by induction), and measuring the potential between pairs of electrodes, calculating the potential expected in each case on the assumption that the body consists of a medium of uniform impedance, plotting the isopotentials corresponding to the calculated results to create a uniform image of the body, obtaining the ratio between the measured potential and the calculated potential in each case, and modifying the image in accordance with the respective ratios by increasing the assumed impedance along an isopotential in proportion to a ratio greater than unity or decreasing the assumed impedance in proportion to a ratio less than unity. The modified impedances along the isopotentials for each pair of electrodes are superimposed. The calculations are carried out using a computer and the plotting is carried out by a visual display unit and/or a print-out unit. (author)

  13. An integrated computer design environment for the development of micro-computer critical software

    International Nuclear Information System (INIS)

    De Agostino, E.; Massari, V.

    1986-01-01

    The paper deals with the development of micro-computer software for Nuclear Safety System. More specifically, it describes an experimental work in the field of software development methodologies to be used for the implementation of micro-computer based safety systems. An investigation of technological improvements that are provided by state-of-the-art integrated packages for micro-based systems development has been carried out. The work has aimed to assess a suitable automated tools environment for the whole software life-cycle. The main safety functions, as DNBR, KW/FT, of a nuclear power reactor have been implemented in a host-target approach. A prototype test-bed microsystem has been implemented to run the safety functions in order to derive a concrete evaluation on the feasibility of critical software according to new technological trends of ''Software Factories''. (author)

  14. The use of micro-computers in the simulation of ion beam optics

    International Nuclear Information System (INIS)

    Spaedtke, P.; Ivens, D.

    1989-01-01

    With computer simulation codes specific problems of the ion beam optics can be studied, which is useful in the design as in optimization of existing systems. Several such codes have been developed, unfortunately requiring substantial computer resources. Recent advances of mini- and micro-computers have now made it possible to develop simulation codes which can be run on these small computers also. In this paper, some of these codes will be presented and their computing time discussed. (author)

  15. Micro-computer based control system and its software for carrying out the sequential acceleration on SMCAMS

    International Nuclear Information System (INIS)

    Li Deming

    2001-01-01

    Micro-computer based control system and its software for carrying out the sequential acceleration on SMCAMS is described. Also, the establishment of the 14 C particle measuring device and the improvement of the original power supply system are described

  16. Label-free, multi-contrast optical coherence tomography for study of skin melanoma mice in vivo

    Science.gov (United States)

    Lai, Pei-Yu; Lin, Tim-Han; Chou, Ya-Shuan; Chang, Chung-Hsing; Kuo, Wen-Chuan

    2018-02-01

    The lymphatic system plays an important role in inflammation and cancer such as melanoma. Due to the limitations of current developed imaging techniques, visualization of lymphatic vessels within the tissue in vivo has been challenging. Optical imaging of lymphatic vessel is gaining increased interests because it does not involve any radiation and can achieve very high resolution. Here, we developed a multi-contrast, label-free optical coherence tomography (OCT) imaging technology with an axial resolution of 5 μm and lateral resolution of 7 μm, which is capable of providing microstructural information and microcirculatory system including blood and lymphatic vessels simultaneously. Using this technique, we observed the melanoma mice in vivo. Mice were treated topically on the ear with (Z)-4- Hydroxytamoxifen(4-OHT) to elicit BRAFV600E and to silence Pten expression. Also, to observing the structural information, angiogenesis and lymphangiogenesis in the ear of the induced melanoma mouse can be done. The advantage of using OCT over other imaging modalities is its ability to assess label-free blood flow along with lymphatic vessels simultaneously for imaging the microcirculatory system within tissue beds without any exogenous agents. Because the metastasis of melanoma is highly related to the lymphatic vessels, our findings can be a powerful tool to help the diagnosis of the metastasis melanoma. In the future, this may become a helpful tool for better understanding pathologic mechanisms and treatment technique development in some diseases.

  17. Grating-based X-ray Dark-field Computed Tomography of Living Mice.

    Science.gov (United States)

    Velroyen, A; Yaroshenko, A; Hahn, D; Fehringer, A; Tapfer, A; Müller, M; Noël, P B; Pauwels, B; Sasov, A; Yildirim, A Ö; Eickelberg, O; Hellbach, K; Auweter, S D; Meinel, F G; Reiser, M F; Bech, M; Pfeiffer, F

    2015-10-01

    Changes in x-ray attenuating tissue caused by lung disorders like emphysema or fibrosis are subtle and thus only resolved by high-resolution computed tomography (CT). The structural reorganization, however, is of strong influence for lung function. Dark-field CT (DFCT), based on small-angle scattering of x-rays, reveals such structural changes even at resolutions coarser than the pulmonary network and thus provides access to their anatomical distribution. In this proof-of-concept study we present x-ray in vivo DFCTs of lungs of a healthy, an emphysematous and a fibrotic mouse. The tomographies show excellent depiction of the distribution of structural - and thus indirectly functional - changes in lung parenchyma, on single-modality slices in dark field as well as on multimodal fusion images. Therefore, we anticipate numerous applications of DFCT in diagnostic lung imaging. We introduce a scatter-based Hounsfield Unit (sHU) scale to facilitate comparability of scans. In this newly defined sHU scale, the pathophysiological changes by emphysema and fibrosis cause a shift towards lower numbers, compared to healthy lung tissue.

  18. Evaluation of the efficacy of zoledronic acid and amifostine on radiation induced bone loss in mice

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Wook; Lee, Sueum; Kang, Sohi; Moon, Cahng Jong; Kim, Jong Choon; Kim, Sung Ho [College of Veterinary Medicine, Chonnam National University, Gwangju (Korea, Republic of); Jung, Uhee; Jo, Sung Kee [Advanced Radiation Technology Institute, Jeungeup (Korea, Republic of); Jang, Jong Sik [College of Ecology and Environmental Science, Kyungpook National University, Sangju (Korea, Republic of)

    2016-09-15

    This study investigated the effects of zoledronic acid (ZA) on radiation-induced bone loss in C3H/HeN mice. C3H/HeN mice were divided into sham control and three irradiated groups (3 Gy, gamma ray). The irradiated mice were treated for 12 weeks with vehicle, amifostine (intraperitoneal injection), or ZA (subcutaneous injection). Grip strength, uterus weight, and serum alkaline phosphatase (ALP), and tartrate-resistant acid phosphatase (TRAP) levels were measured. Tibiae were analyzed using micro-computed tomography. Treatment of ZA (100 μg·kg{sup -1}·week{sup -1}) significantly preserved trabecular bone volume, trabecular thickness, trabecular number, trabecular separation, bone mineral density of proximal tibia metaphysic, and cortical bone volume, but did not alter the uterus weight of the mice. The administration of ZA for 12 weeks lowered serum ALP and TRAP levels in irradiated mice, suggesting that ZA can reduce the bone turnover rate in mice. No differences were apparent between the amifostine-treated group and the irradiation control group. The results indicate that ZA can prevent radiation-induced bone loss in mice.

  19. Impaired bone healing at tooth extraction sites in CD24-deficient mice: A pilot study.

    Science.gov (United States)

    Avivi-Arber, Limor; Avivi, Doran; Perez, Marilena; Arber, Nadir; Shapira, Shiran

    2018-01-01

    To use a micro-computed tomography (micro-CT) to quantify bone healing at maxillary first molar extraction sites, and test the hypothesis that bone healing is impaired in CD24-knockout mice as compared with wild-type C57BL/6J mice. Under ketamine-xylazine general anaesthesia, mice had either extraction of the right maxillary first molar tooth or sham operation. Mice were sacrificed 1 (n = 12/group), 2 (n = 6/group) or 4 (n = 6/group) weeks postoperatively. The right maxillae was disected. Micro-CT was used to quantify differences in bone microstructural features at extrction sites, between CD24-knockout mice and wild-type mice. CD24-Knockout mice displayed impaired bone healing at extraction sites that was manifested as decreased trabecular bone density, and decreased number and thickness of trabeculae. This pilot study suggests that CD24 plays an important role in extraction socket bone healing and may be used as a novel biomarker of bone quality and potential therapeutic target to improve bone healing and density following alveolar bone injury.

  20. CEGB philosophy and experience with fault-tolerant micro-computer application for power plant controls

    International Nuclear Information System (INIS)

    Clinch, D.A.L.

    1986-01-01

    From the mid-1960s until the late 1970s, automatic modulating control of the main boiler plant on CEGB fossil-fired power stations was largely implemented with hard wired electronic equipment. Mid-way through this period, the CEGB formulated a set of design requirements for this type of equipment; these laid particular emphasis on the fault tolerance of a control system and specified the nature of the interfaces with a control desk and with plant regulators. However, the automatic control of an Advanced Gas Cooled Reactor (AGR) is based upon measured values which are derived by processing a large number of thermocouple signals. This is more readily implemented digitally than with hard-wired equipment. Essential to the operation of an AGR power station is a data processing (DP) computer for monitoring the plant; so the first group of AGR power stations, designed in the 1960s, employed their DP computers for modulating control. Since the late 1970s, automatic modulating control of major plants, for new power stations and for re-fits on established power stations, has been implemented with micro-computers. Wherever practicable, the policy formulated earlier for hard-wired equipment has been retained, particularly in respect of the interfaces. This policy forms the foundation of the fault tolerance of these micro-computer systems

  1. Speckle-modulating optical coherence tomography in living mice and humans

    Science.gov (United States)

    Liba, Orly; Lew, Matthew D.; Sorelle, Elliott D.; Dutta, Rebecca; Sen, Debasish; Moshfeghi, Darius M.; Chu, Steven; de La Zerda, Adam

    2017-06-01

    Optical coherence tomography (OCT) is a powerful biomedical imaging technology that relies on the coherent detection of backscattered light to image tissue morphology in vivo. As a consequence, OCT is susceptible to coherent noise (speckle noise), which imposes significant limitations on its diagnostic capabilities. Here we show speckle-modulating OCT (SM-OCT), a method based purely on light manipulation that virtually eliminates speckle noise originating from a sample. SM-OCT accomplishes this by creating and averaging an unlimited number of scans with uncorrelated speckle patterns without compromising spatial resolution. Using SM-OCT, we reveal small structures in the tissues of living animals, such as the inner stromal structure of a live mouse cornea, the fine structures inside the mouse pinna, and sweat ducts and Meissner's corpuscle in the human fingertip skin--features that are otherwise obscured by speckle noise when using conventional OCT or OCT with current state of the art speckle reduction methods.

  2. Changes in bone macro- and microstructure in diabetic obese mice revealed by high resolution microfocus X-ray computed tomography

    Science.gov (United States)

    Kerckhofs, G.; Durand, M.; Vangoitsenhoven, R.; Marin, C.; van der Schueren, B.; Carmeliet, G.; Luyten, F. P.; Geris, L.; Vandamme, K.

    2016-10-01

    High resolution microfocus X-ray computed tomography (HR-microCT) was employed to characterize the structural alterations of the cortical and trabecular bone in a mouse model of obesity-driven type 2 diabetes (T2DM). C57Bl/6J mice were randomly assigned for 14 weeks to either a control diet-fed (CTRL) or a high fat diet (HFD)-fed group developing obesity, hyperglycaemia and insulin resistance. The HFD group showed an increased trabecular thickness and a decreased trabecular number compared to CTRL animals. Midshaft tibia intracortical porosity was assessed at two spatial image resolutions. At 2 μm scale, no change was observed in the intracortical structure. At 1 μm scale, a decrease in the cortical vascular porosity of the HFD bone was evidenced. The study of a group of 8 week old animals corresponding to animals at the start of the diet challenge revealed that the decreased vascular porosity was T2DM-dependant and not related to the ageing process. Our results offer an unprecedented ultra-characterization of the T2DM compromised skeletal micro-architecture and highlight an unrevealed T2DM-related decrease in the cortical vascular porosity, potentially affecting the bone health and fragility. Additionally, it provides some insights into the technical challenge facing the assessment of the rodent bone structure using HR-microCT imaging.

  3. Studies on functional roles of the histaminergic neuron system by using pharmacological agents, knockout mice and positron emission tomography

    International Nuclear Information System (INIS)

    Watanabe, Takehiko; Yanai, Kazuhiko

    2001-01-01

    Since one of us, Takehiko Watanabe (TW), elucidated the location and distribution of the histaminergic neuron system in the brain with antibody raised against L-histidine decarboxylase (a histamine-forming enzyme, HDC) as a marker in 1984 and came to Tohoku University School of Medicine in Sendai, we have been collaborating on the functions of this neuron system by using pharmacological agents, knockout mice of the histamine-related genes, and, in some cases, positron emission tomography (PET). Many of our graduate students and colleagues have been actively involved in histamine research since 1985. Our extensive studies have clarified some of the functions of histamine neurons using methods from molecular techniques to non-invasive human PET imaging. Histamine neurons are involved in many brain functions, such as spontaneous locomotion, arousal in wake-sleep cycle, appetite control, seizures, learning and memory, aggressive behavior and emotion. Particularly, the histaminergic neuron system is one of the most important neuron systems to maintain and stimulate wakefulness. Histamine also functions as a biprotection system against various noxious and unfavorable stimuli (for examples, convulsion, nociception, drug sensitization, ischemic lesions, and stress). Although activators of histamine neurons have not been clinically available until now, we would like to point out that the activation of the histaminergic neuron system is important to maintain mental health. Here, we summarize the newly-discovered functions of histamine neurons mainly on the basis of results from our research groups. (author)

  4. Neuroleptic binding sites: specific labeling in mice with [18F]haloperidol, a potential tracer for positron emission tomography

    International Nuclear Information System (INIS)

    Zanzonico, P.B.; Bigler, R.E.; Schmall, B.

    1983-01-01

    Haloperidol labeled with fluorine- 18 (T 1/2 . 110 min, positron emission 97%), prepared yielding .04 Ci/millimole by the Balz-Schiemann reaction, was evaluated in a murine model as a potential radiotracer for noninvasive determination, by positron-emission tomography, of regional concentrations of brain dopamine receptors in patients. As the haloperidol dose in mice was increased from 0.01 to 1000 micrograms/kg, the relative concentration of [ 18 F]haloperidol (microCi per g specimen/microCi per g of body mass), at one hour after injection decreased from 30 to 1.0 in the striatum and from 8.0 to 1.0 in the cerebellum. The striatal radioactivity, plotted as relative concentration against log of dose, decreased sigmoidally, presumably reflecting competition between labeled and unlabeled haloperidol for a single class of accessible binding sites. Because the cerebellum is relatively deficient in dopamine receptors, the observed decrease in cerebellar radioactivity may reflect a saturable component of haloperidol transport into brain. The high brain concentrations and the unexpectedly high striatum-to-cerebellum concentration ratios (greater than 4 at haloperidol doses less than or equal to 1 microgram/kg) suggest that [ 18 F]haloperidol warrants further investigation as a potential radiotracer for dopamine receptors

  5. Changes in bone macro- and microstructure in diabetic obese mice revealed by high resolution microfocus X-ray computed tomography

    Science.gov (United States)

    Kerckhofs, G.; Durand, M.; Vangoitsenhoven, R.; Marin, C.; Van der Schueren, B.; Carmeliet, G.; Luyten, F. P.; Geris, L.; Vandamme, K.

    2016-01-01

    High resolution microfocus X-ray computed tomography (HR-microCT) was employed to characterize the structural alterations of the cortical and trabecular bone in a mouse model of obesity-driven type 2 diabetes (T2DM). C57Bl/6J mice were randomly assigned for 14 weeks to either a control diet-fed (CTRL) or a high fat diet (HFD)-fed group developing obesity, hyperglycaemia and insulin resistance. The HFD group showed an increased trabecular thickness and a decreased trabecular number compared to CTRL animals. Midshaft tibia intracortical porosity was assessed at two spatial image resolutions. At 2 μm scale, no change was observed in the intracortical structure. At 1 μm scale, a decrease in the cortical vascular porosity of the HFD bone was evidenced. The study of a group of 8 week old animals corresponding to animals at the start of the diet challenge revealed that the decreased vascular porosity was T2DM-dependant and not related to the ageing process. Our results offer an unprecedented ultra-characterization of the T2DM compromised skeletal micro-architecture and highlight an unrevealed T2DM-related decrease in the cortical vascular porosity, potentially affecting the bone health and fragility. Additionally, it provides some insights into the technical challenge facing the assessment of the rodent bone structure using HR-microCT imaging. PMID:27759061

  6. Studies on functional roles of the histaminergic neuron system by using pharmacological agents, knockout mice and positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Takehiko; Yanai, Kazuhiko [Tohoku Univ., Sendai (Japan). Graduate School of Medicine

    2001-12-01

    Since one of us, Takehiko Watanabe (TW), elucidated the location and distribution of the histaminergic neuron system in the brain with antibody raised against L-histidine decarboxylase (a histamine-forming enzyme, HDC) as a marker in 1984 and came to Tohoku University School of Medicine in Sendai, we have been collaborating on the functions of this neuron system by using pharmacological agents, knockout mice of the histamine-related genes, and, in some cases, positron emission tomography (PET). Many of our graduate students and colleagues have been actively involved in histamine research since 1985. Our extensive studies have clarified some of the functions of histamine neurons using methods from molecular techniques to non-invasive human PET imaging. Histamine neurons are involved in many brain functions, such as spontaneous locomotion, arousal in wake-sleep cycle, appetite control, seizures, learning and memory, aggressive behavior and emotion. Particularly, the histaminergic neuron system is one of the most important neuron systems to maintain and stimulate wakefulness. Histamine also functions as a biprotection system against various noxious and unfavorable stimuli (for examples, convulsion, nociception, drug sensitization, ischemic lesions, and stress). Although activators of histamine neurons have not been clinically available until now, we would like to point out that the activation of the histaminergic neuron system is important to maintain mental health. Here, we summarize the newly-discovered functions of histamine neurons mainly on the basis of results from our research groups. (author)

  7. Imaging retinal degeneration in mice by combining Fourier domain optical coherence tomography and fluorescent scanning laser ophthalmoscopy

    Science.gov (United States)

    Hossein-Javaheri, Nima; Molday, Laurie L.; Xu, Jing; Molday, Robert S.; Sarunic, Marinko V.

    2009-02-01

    Visualization of the internal structures of the retina is critical for clinical diagnosis and monitoring of pathology as well as for medical research investigating the root causes of retinal degeneration. Optical Coherence Tomography (OCT) is emerging as the preferred technique for non-contact sub-surface depth-resolved imaging of the retina. The high resolution cross sectional images acquired in vivo by OCT can be compared to histology to visually delineate the retinal layers. The recent demonstration of the significant sensitivity increase obtained through use of Fourier domain (FD) detection with OCT has been used to facilitate high speed scanning for volumetric reconstruction of the retina in software. The images acquired by OCT are purely structural, relying on refractive index differences in the tissue for contrast, and do not provide information on the molecular content of the sample. We have constructed a FDOCT prototype and combined it with a fluorescent Scanning Laser Ophthalmoscope (fSLO) to permit real time alignment of the field of view on the retina. The alignment of the FDOCT system to the specimen is crucial for the registration of measurements taken throughout longitudinal studies. In addition, fluorescence detection has been integrated with the SLO to enable the en face localization of a molecular contrast signal, which is important for retinal angiography, and also for detection of autofluorescence associated with some forms of retinal degeneration, for example autofluorescence lipofuscin accumulations are associated with Stargardt's Macular Dystrophy. The integrated FD OCT/fSLO system was investigated for imaging the retina of the mice in vivo.

  8. Effects of Active Mastication on Chronic Stress-Induced Bone Loss in Mice.

    Science.gov (United States)

    Azuma, Kagaku; Furuzawa, Manabu; Fujiwara, Shu; Yamada, Kumiko; Kubo, Kin-ya

    2015-01-01

    Chronic psychologic stress increases corticosterone levels, which decreases bone density. Active mastication or chewing attenuates stress-induced increases in corticosterone. We evaluated whether active mastication attenuates chronic stress-induced bone loss in mice. Male C57BL/6 (B6) mice were randomly divided into control, stress, and stress/chewing groups. Stress was induced by placing mice in a ventilated restraint tube (60 min, 2x/day, 4 weeks). The stress/chewing group was given a wooden stick to chew during the experimental period. Quantitative micro-computed tomography, histologic analysis, and biochemical markers were used to evaluate the bone response. The stress/chewing group exhibited significantly attenuated stress-induced increases in serum corticosterone levels, suppressed bone formation, enhanced bone resorption, and decreased trabecular bone mass in the vertebrae and distal femurs, compared with mice in the stress group. Active mastication during exposure to chronic stress alleviated chronic stress-induced bone density loss in B6 mice. Active mastication during chronic psychologic stress may thus be an effective strategy to prevent and/or treat chronic stress-related osteopenia.

  9. Imaging Primary Lung Cancers in Mice to Study Radiation Biology

    International Nuclear Information System (INIS)

    Kirsch, David G.; Grimm, Jan; Guimaraes, Alexander R.; Wojtkiewicz, Gregory R.; Perez, Bradford A.; Santiago, Philip M.; Anthony, Nikolas K.; Forbes, Thomas; Doppke, Karen

    2010-01-01

    Purpose: To image a genetically engineered mouse model of non-small-cell lung cancer with micro-computed tomography (micro-CT) to measure tumor response to radiation therapy. Methods and Materials: The Cre-loxP system was used to generate primary lung cancers in mice with mutation in K-ras alone or in combination with p53 mutation. Mice were serially imaged by micro-CT, and tumor volumes were determined. A comparison of tumor volume by micro-CT and tumor histology was performed. Tumor response to radiation therapy (15.5 Gy) was assessed with micro-CT. Results: The tumor volume measured with free-breathing micro-CT scans was greater than the volume calculated by histology. Nevertheless, this imaging approach demonstrated that lung cancers with mutant p53 grew more rapidly than lung tumors with wild-type p53 and also showed that radiation therapy increased the doubling time of p53 mutant lung cancers fivefold. Conclusions: Micro-CT is an effective tool to noninvasively measure the growth of primary lung cancers in genetically engineered mice and assess tumor response to radiation therapy. This imaging approach will be useful to study the radiation biology of lung cancer.

  10. Lactobacillus salivarius Isolated from Patients with Rheumatoid Arthritis Suppresses Collagen-Induced Arthritis and Increases Treg Frequency in Mice.

    Science.gov (United States)

    Liu, Xiaofei; Zhang, Juan; Zou, Qinghua; Zhong, Bing; Wang, Heng; Mou, Fangxiang; Wu, Like; Fang, Yongfei

    2016-12-01

    Previously, we demonstrated that Lactobacillus salivarius was more abundant in patients with rheumatoid arthritis (RA), an inflammatory autoimmune disease wherein the gut microbiota is altered, than in healthy individuals. However, the effect of L. salivarius in RA is unclear. Hence, we investigated the effect of L. salivarius isolated from patients with RA on collagen-induced arthritis (CIA) in mice. L. salivarius UCC118 or L. plantarum WCFS1 isolated from patients with RA was administered orally for 5 weeks, starting from 2 weeks before the induction of arthritis in DBA/1 mice. Clinical score progression, histological changes, serum cytokine concentrations, and the proportion of interleukin (IL)-17-producing T cells [T helper 17 (Th17)] and regulatory T cells (Tregs) in the spleen were evaluated. Bone erosion was evaluated by micro-computed tomography. CIA mice treated with either L. salivarius or L. plantarum showed lower arthritis scores, milder synovial infiltration, and less bone erosion when compared with phosphate-buffered, saline-treated CIA mice. Administration of L. salivarius and L. plantarum reduced the Th17 cell fraction and increased the Treg fraction. L. salivarius-treated CIA mice displayed a significant increase in serum anti-inflammatory IL-10 levels. Thus, pretreatment with L. salivarius could significantly improve CIA in mice and may help alleviate RA in a clinical setting.

  11. Gamma spectra analysis from a NaI(Tl) scintillation detector using a micro-computer

    International Nuclear Information System (INIS)

    Levinson, S.

    1990-01-01

    A software package of programs was devloped for qualitative and quantitative evaluation of gamma ray spectra obtained from a NaI(Tl) scintilation counter, by means of a micro-computer. The programs can easily be transformed for use with a Ge(Li) detector. The various algorithms enable automatic analyzing of a spectrum and also interactive or manual mode. The graphic programs display the measured spectrum as well as spectra of standard radionuclides which helps in the determination of peaks and related radionuclides in the spectrum. The peak search is carried out on a smoothed spectrum and is done by checking the behaviour of the second and third derivatives. The algorithm solves the problem of overlapping peaks and performs gaussian fitting, if necessary. Determination of the various radionuclides in the spectrum is done by linear minimum least squares techniques. Overall analysis of the radionuclides activities in the spectrum is obtained for samples of various counting geometries. In addition, a model was developed for efficiency calibration of flat 3X3 inch NaI(Tl) detectors for different samples measured in various counting geometries. It is based on point source experimental efficiency curve fitting. (author)

  12. Data processing system with a micro-computer for high magnetic field tokamak, TRIAM-1

    International Nuclear Information System (INIS)

    Kawasaki, Shoji; Nakamura, Kazuo; Nakamura, Yukio; Hiraki, Naoharu; Toi, Kazuo

    1981-01-01

    A data processing system was designed and constructed for the purpose of analyzing the data of the high magnetic field tokamak TRIAM-1. The system consists of a 10-channel A-D converter, a 20 K byte memory (RAM), an address bus control circuit, a data bus control circuit, a timing pulse and control signal generator, a D-A converter, a micro-computer, and a power source. The memory can be used as a CPU memory except at the time of sampling and data output. The out-put devices of the system are an X-Y recorder and an oscilloscope. The computer is composed of a CPU, a memory and an I/O part. The memory size can be extended. A cassette tape recorder is provided to keep the programs of the computer. An interface circuit between the computer and the tape recorder was designed and constructed. An electric discharge printer as an I/O device can be connected. From TRIAM-1, the signals of magnetic probes, plasma current, vertical field coil current, and one-turn loop voltage are fed into the processing system. The plasma displacement calculated from these signals is shown by one of I/O devices. The results of test run showed good performance. (Kato, T.)

  13. Data processing system with a micro-computer for high magnetic field tokamak, TRIAM-1

    Energy Technology Data Exchange (ETDEWEB)

    Kawasaki, S; Nakamura, K; Nakamura, Y; Hiraki, N; Toi, K [Kyushu Univ., Fukuoka (Japan). Research Inst. for Applied Mechanics

    1981-02-01

    A data processing system was designed and constructed for the purpose of analyzing the data of the high magnetic field tokamak TRIAM-1. The system consists of a 10-channel A-D converter, a 20 K byte memory (RAM), an address bus control circuit, a data bus control circuit, a timing pulse and control signal generator, a D-A converter, a micro-computer, and a power source. The memory can be used as a CPU memory except at the time of sampling and data output. The out-put devices of the system are an X-Y recorder and an oscilloscope. The computer is composed of a CPU, a memory and an I/O part. The memory size can be extended. A cassette tape recorder is provided to keep the programs of the computer. An interface circuit between the computer and the tape recorder was designed and constructed. An electric discharge printer as an I/O device can be connected. From TRIAM-1, the signals of magnetic probes, plasma current, vertical field coil current, and one-turn loop voltage are fed into the processing system. The plasma displacement calculated from these signals is shown by one of I/O devices. The results of test run showed good performance.

  14. A micro-computed tomographic evaluation of dentinal microcrack alterations during root canal preparation using single-file Ni-Ti systems.

    Science.gov (United States)

    Li, Mei-Lin; Liao, Wei-Li; Cai, Hua-Xiong

    2018-01-01

    The aim of the present study was to evaluate the length of dentinal microcracks observed prior to and following root canal preparation with different single-file nickel-titanium (Ni-Ti) systems using micro-computed tomography (micro-CT) analysis. A total of 80 mesial roots of mandibular first molars presenting with type II Vertucci canal configurations were scanned at an isotropic resolution of 7.4 µm. The samples were randomly assigned into four groups (n=20 per group) according to the system used for root canal preparation, including the WaveOne (WO), OneShape (OS), Reciproc (RE) and control groups. A second micro-CT scan was conducted after the root canals were prepared with size 25 instruments. Pre- and postoperative cross-section images of the roots (n=237,760) were then screened to identify the lengths of the microcracks. The results indicated that the microcrack lengths were notably increased following root canal preparation (Pfiles. Among the single-file Ni-Ti systems, WO and RE were not observed to cause notable microcracks, while the OS system resulted in evident microcracks.

  15. Observation of microscopic bone structure during bone formation. Application of micro-computed tomography for evaluation of bone quality

    International Nuclear Information System (INIS)

    Ueno, Takaaki; Yamamoto, Hiromitsu; Mizukawa, Nobuyoshi; Mishima, Katsuaki; Takagi, Shin; Sugahara, Toshio

    1998-01-01

    Bone formation in the autogenous periosteum of the tibia grafted to the floor of the mouth to bridge the mandible was studied by micro-CT to assess its efficacy in evaluating bone formation in rabbits. On soft radiographs, bone formation was observed from both ends of the periosteum on day 14. The bone increased in width and extended medially; contact was made in the center on day 28. The time course of the development of bone trabeculae was well demonstrated three-dimensionally on micro-CT. Indices of bone quality such as Tb-Th, Tb.N, and BV, which reflect the growth of trabeculae, increased gradually from days 14 to 21 and more rapidly from days 21 to 28, whereas Tb. S decreased gradually after grafting. The results suggest that micro-CT is useful in evaluating bone formation three-dimensionally. (author)

  16. Assessing accumulated hard-tissue debris using micro-computed tomography and free software for image processing and analysis.

    Science.gov (United States)

    De-Deus, Gustavo; Marins, Juliana; Neves, Aline de Almeida; Reis, Claudia; Fidel, Sandra; Versiani, Marco A; Alves, Haimon; Lopes, Ricardo Tadeu; Paciornik, Sidnei

    2014-02-01

    The accumulation of debris occurs after root canal preparation procedures specifically in fins, isthmus, irregularities, and ramifications. The aim of this study was to present a step-by-step description of a new method used to longitudinally identify, measure, and 3-dimensionally map the accumulation of hard-tissue debris inside the root canal after biomechanical preparation using free software for image processing and analysis. Three mandibular molars presenting the mesial root with a large isthmus width and a type II Vertucci's canal configuration were selected and scanned. The specimens were assigned to 1 of 3 experimental approaches: (1) 5.25% sodium hypochlorite + 17% EDTA, (2) bidistilled water, and (3) no irrigation. After root canal preparation, high-resolution scans of the teeth were accomplished, and free software packages were used to register and quantify the amount of accumulated hard-tissue debris in either canal space or isthmus areas. Canal preparation without irrigation resulted in 34.6% of its volume filled with hard-tissue debris, whereas the use of bidistilled water or NaOCl followed by EDTA showed a reduction in the percentage volume of debris to 16% and 11.3%, respectively. The closer the distance to the isthmus area was the larger the amount of accumulated debris regardless of the irrigating protocol used. Through the present method, it was possible to calculate the volume of hard-tissue debris in the isthmuses and in the root canal space. Free-software packages used for image reconstruction, registering, and analysis have shown to be promising for end-user application. Copyright © 2014. Published by Elsevier Inc.

  17. Three-dimensional in vivo imaging of the murine liver: a micro-computed tomography-based anatomical study.

    Directory of Open Access Journals (Sweden)

    Teresa Fiebig

    Full Text Available Various murine models are currently used to study acute and chronic pathological processes of the liver, and the efficacy of novel therapeutic regimens. The increasing availability of high-resolution small animal imaging modalities presents researchers with the opportunity to precisely identify and describe pathological processes of the liver. To meet the demands, the objective of this study was to provide a three-dimensional illustration of the macroscopic anatomical location of the murine liver lobes and hepatic vessels using small animal imaging modalities. We analysed micro-CT images of the murine liver by integrating additional information from the published literature to develop comprehensive illustrations of the macroscopic anatomical features of the murine liver and hepatic vasculature. As a result, we provide updated three-dimensional illustrations of the macroscopic anatomy of the murine liver and hepatic vessels using micro-CT. The information presented here provides researchers working in the field of experimental liver disease with a comprehensive, easily accessable overview of the macroscopic anatomy of the murine liver.

  18. Comparison of three retreatment techniques with ultrasonic activation in flattened canals using micro-computed tomography and scanning electron microscopy.

    Science.gov (United States)

    Bernardes, R A; Duarte, M A H; Vivan, R R; Alcalde, M P; Vasconcelos, B C; Bramante, C M

    2015-08-17

    To use micro-CT to quantitatively evaluate the amount of residual filling material after using several techniques to remove root fillings with and without ultrasonic activation and to analyse the cleanliness of the root canal walls and dentine tubules with scanning electron microscopy (SEM). The root canals of one hundred and eight human mandibular incisors were selected and instrumented with rotary files using the BioRace system up to file size 40, .04 taper. After instrumentation, the teeth were filled using a hybrid technique with gutta-percha and sealer then divided into three groups according to the method used for removing the root filling: G1-Reciproc (using only instrument R50), G2-ProTaper Universal retreatment system and G3-Manual (hand files and Gates-Glidden burs). All groups were divided into two subgroups depending on whether ultrasonic agitation was used with the irrigants. Micro-CT scans were taken before and after removal of the filling material to detect residual material in the canal. After micro-CT analysis, the roots were cut in half, imaged by SEM and scored based on the amount of surface covered by root filling remnants. The data were analysed statistically using a significance level of 5%. All groups had retained material in the root canals after instrumentation. The Reciproc method was associated with less retained material than the ProTaper and Manual methods. Ultrasonic activation significantly reduced the amount of residual root filling in all groups (P material. Ultrasonic activation improved the removal of root filling material in all groups. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  19. The bisphosphonate zoledronate prevents vertebral bone loss in mature estrogen-deficient rats as assessed by micro-computed tomography

    Directory of Open Access Journals (Sweden)

    Glatt M.

    2001-01-01

    Full Text Available The effect of long-term treatment with the bisphosphonate zoledronate on vertebral bone architecture was investigated in estrogen-deficient mature rats. 4-month-old rats were ovariectomized and development of cancellous osteopenia was assessed after 1 year. The change of bone architectural parameters was determined with a microtomographic instrument of high resolution. After 1 year of estrogen-deficiency, animals lost 55% of vertebral trabecular bone in comparison to sham operated control animals. Trabecular number (Tb.N and trabecular thickness (Tb.Th were significantly reduced in ovariectomized animals, whereas trabecular separation (Tb.Sp, bone surface to volume fraction (BS/BV and trabecular bone pattern factor (TBPf were significantly increased, indicating a loss of architectural integrity throughout the vertebral body. 3 groups of animals were treated subcutaneously with zoledronate for 1 year with 0.3, 1.5 and 7.5 microgram/kg/week to inhibit osteoclastic bone degradation. Administration started immediately after ovariectomy and treatment dose-dependently prevented the architectural bone deterioration and completely suppressed the effects of estrogen deficiency at the higher doses. The results show that microtomographic determination of static morphometric parameters can be used to quantitate the effects of drugs on vertebral bone architecture in small laboratory animals and that zoledronate is highly effective in this rat model.

  20. Influence of 24-Nor-Ursodeoxycholic Acid on Hepatic Disposition of [(18)F]Ciprofloxacin, a Positron Emission Tomography Study in Mice.

    Science.gov (United States)

    Wanek, Thomas; Halilbasic, Emina; Visentin, Michele; Mairinger, Severin; Römermann, Kerstin; Stieger, Bruno; Kuntner, Claudia; Müller, Markus; Langer, Oliver; Trauner, Michael

    2016-01-01

    24-nor-ursodeoxycholic acid (norUDCA) is a novel therapeutic approach to cholestatic liver diseases. In mouse models of cholestasis, norUDCA induces basolateral multidrug resistance-associated proteins 4 (Mrp4) and 3 in hepatocytes, which provide alternative escape routes for bile acids accumulating during cholestasis but could also result in altered hepatic disposition of concomitantly administered substrate drugs. We used positron emission tomography imaging to study the influence of norUDCA on hepatic disposition of the model Mrp4 substrate [(18)F]ciprofloxacin in wild-type and Mdr2((-/-)) mice, a model of cholestasis. Animals underwent [(18)F]ciprofloxacin positron emission tomography at baseline and after norUDCA treatment. After norUDCA treatment, liver-to-blood area under the curve ratio of [(18)F]ciprofloxacin was significantly decreased compared to baseline, both in wild-type (-34.0 ± 2.1%) and Mdr2((-/-)) mice (-20.5 ± 6.0%). [(18)F]Ciprofloxacin uptake clearance from blood into liver was reduced by -17.1 ± 9.0% in wild-type and by -20.1 ± 7.3% in Mdr2((-/-)) mice. Real-time PCR analysis showed significant increases in hepatic Mrp4 and multidrug resistance-associated protein 3 mRNA after norUDCA. Transport experiments in organic anion transporting polypeptide (OATP)1B1-, OATP1B3-, and OATP2B1-transfected cells revealed weak transport of [(14)C]ciprofloxacin by OATP1B3 and OATP2B1 and no inhibition by norUDCA. In conclusion, our data suggest that changes in hepatic [(18)F]ciprofloxacin disposition in mice after norUDCA treatment were caused by induction of basolateral Mrp4 in hepatocytes. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  1. Piroxicam treatment augments bone abnormalities in interleukin-10 knockout mice.

    Science.gov (United States)

    Holgersen, Kristine; Dobie, Ross; Farquharson, Colin; vanʼt Hof, Rob; Ahmed, Syed Faisal; Hansen, Axel Kornerup; Holm, Thomas L

    2015-02-01

    Osteoporosis and fractures are common complications of inflammatory bowel disease. The pathogenesis is multifactorial and has been partly attributed to intestinal inflammation. The aim of this study was to evaluate bone status and assess the association between bone loss and gut inflammation in an experimental colitis model. Colitis was induced in interleukin-10 knockout mice (PAC IL-10 k.o.) by peroral administration of piroxicam for 12 days. The degree of colitis was assessed by clinical, macroscopic, and microscopic evaluation. Trabecular and cortical bone microarchitecture of tibia were determined using micro-computed tomography. Moreover, the serum levels of bone formation and bone resorption biomarkers were measured, and inflammatory protein profiling was performed on colons. PAC IL-10 k.o. mice developed severe colitis, characterized by hyperplasia and focal transmural inflammation, which was consistent with Crohn's disease-like pathology. The gut inflammation was accompanied by a 14% and 12% reduction in trabecular thickness relative to piroxicam-treated wild type and untreated wild type mice, respectively (P < 0.001). The trabecular bone structure was also changed in PAC IL-10 k.o. mice, whereas no differences in cortical bone geometry were observed. The trabecular thickness was inversely correlated with serum levels of CTX (r = -0.93, P = 0.006). Moreover, numerous inflammatory mediators, including RANKL and osteoprotegerin, were significantly increased in the colon of PAC IL-10 k.o. mice. PAC IL-10 k.o. mice develop bone loss and changed trabecular structure, as a result of increased bone resorption. Thus, the PAC IL-10 k.o. model could be a useful experimental model in preclinical research of inflammatory bowel disease-associated bone loss.

  2. On-line pressurizer surveillance system design to prevent small break LOCA through PORV using micro-computer

    International Nuclear Information System (INIS)

    Lee, Jong-Ho; Chang, Soon-Heung

    1986-01-01

    Small break LOCA caused by a stuck-open PORV is one of the important contributors to nuclear power plant risk. This paper deals with the design of a pressurizer surveillance system using micro-computer to prevent the malfunction of system and has assessed the effect of this improvement through Probabilistic Risk Assessment (PRA) method. Micro-computer diagnoses the malfunction of system by a process checking method and performs automatically backup action related to each malfunction. Owing to this improvement, we can correctly diagnose ''Spurious Opening'', ''Fail to Reclose'' and ''Small break LOCA'' which are difficult for operator to diagnose quickly and correctly and reduce the probability of a human error by an automatic backup action. (author)

  3. 3D map of theranostic nanoparticles distribution in mice brain and liver by means of X-ray Phase Contrast Tomography

    Science.gov (United States)

    Longo, E.; Bravin, A.; Brun, F.; Bukreeva, I.; Cedola, A.; Fratini, M.; Le Guevel, X.; Massimi, L.; Sancey, L.; Tillement, O.; Zeitoun, P.; de La Rochefoucauld, O.

    2018-01-01

    The word "theranostic" derives from the fusion of two terms: therapeutic and diagnostic. It is a promising research field that aims to develop innovative therapies with high target specificity by exploiting the therapeutic and diagnostic properties, in particular for metal-based nanoparticles (NPs) developed to erase cancer. In the framework of a combined research program on low dose X-ray imaging and theranostic nanoparticles (NPs), high resolution Phase-Contrast Tomography images of mice organs injected with gadolinium and gold-NPs were acquired at the European Synchrotron Radiation Facility (ESRF). Both compounds are good X-ray contrast agents due to their high attenuation coefficient with respect to biological tissues, especially immediately above K-edge energy. X-ray tomography is a powerful non-invasive technique to image the 3D vasculature network in order to detect abnormalities. Phase contrast methods provide more detailed anatomical information with higher discrimination among soft tissues. We present the images of mice liver and brain injected with gold and gadolinium NPs, respectively. We discuss different image processing methods used aiming at enhancing the accuracy on localizing nanoparticles.

  4. A versatile data handling system for nuclear physics experiments based on PDP 11/03 micro-computers

    International Nuclear Information System (INIS)

    Raaf, A.J. de

    1979-01-01

    A reliable and low cost data handling system for nuclear physics experiments is described. It is based on two PDP 11/03 micro-computers together with Gec-Elliott CAMAC equipment. For the acquisition of the experimental data a fast system has been designed. It consists of a controller for four ADCs together with an intelligent 38k MOS memory with a word size of 24 bits. (Auth.)

  5. A memory efficient user interface for CLIPS micro-computer applications

    Science.gov (United States)

    Sterle, Mark E.; Mayer, Richard J.; Jordan, Janice A.; Brodale, Howard N.; Lin, Min-Jin

    1990-01-01

    The goal of the Integrated Southern Pine Beetle Expert System (ISPBEX) is to provide expert level knowledge concerning treatment advice that is convenient and easy to use for Forest Service personnel. ISPBEX was developed in CLIPS and delivered on an IBM PC AT class micro-computer, operating with an MS/DOS operating system. This restricted the size of the run time system to 640K. In order to provide a robust expert system, with on-line explanation, help, and alternative actions menus, as well as features that allow the user to back up or execute 'what if' scenarios, a memory efficient menuing system was developed to interface with the CLIPS programs. By robust, we mean an expert system that (1) is user friendly, (2) provides reasonable solutions for a wide variety of domain specific problems, (3) explains why some solutions were suggested but others were not, and (4) provides technical information relating to the problem solution. Several advantages were gained by using this type of user interface (UI). First, by storing the menus on the hard disk (instead of main memory) during program execution, a more robust system could be implemented. Second, since the menus were built rapidly, development time was reduced. Third, the user may try a new scenario by backing up to any of the input screens and revising segments of the original input without having to retype all the information. And fourth, asserting facts from the menus provided for a dynamic and flexible fact base. This UI technology has been applied successfully in expert systems applications in forest management, agriculture, and manufacturing. This paper discusses the architecture of the UI system, human factors considerations, and the menu syntax design.

  6. Micro-computed Tomographic Analysis of Mandibular Second Molars with C-shaped Root Canals.

    Science.gov (United States)

    Amoroso-Silva, Pablo Andrés; Ordinola-Zapata, Ronald; Duarte, Marco Antonio Hungaro; Gutmann, James L; del Carpio-Perochena, Aldo; Bramante, Clovis Monteiro; de Moraes, Ivaldo Gomes

    2015-06-01

    The goal of the present study was to evaluate the morphometric aspects of the internal anatomy of the root canal system of mandibular second molars with C-shaped canals. Fifty-two extracted second mandibular molars with C-shaped canals, fused roots, and radicular grooves were selected from a Brazilian population. The samples were scanned with a micro-computed tomographic scanner at a voxel size of 19.6 μm. The root canal cross sections were recorded as C1, C2, C3, and C4 root canal configurations according to the modified Melton classification. Morphometric parameters, including the major and minor diameters of the root canals, the aspect ratio, the roundness, and the tridimensional configuration (merging, symmetric, and asymmetric), were evaluated. The 3-dimensional reconstruction images of the teeth indicated an even distribution within the sample. The analysis of the prevalence of the different cross-sectional configurations of the C-shaped molars revealed that these were predominantly of the C4 and C3 configurations (1 mm from the apex) and the C1 and C2 configurations in the cervical third. According to the morphometric parameters, the C1 and the distal aspect of the C2 configurations exhibited the lowest roundness values and higher values for the area, major diameter, and aspect ratio in the apical third. Mandibular molars with C-shaped root canals exhibited similar distributions of symmetric, asymmetric, and merging type canals. The C1 configuration and the distal aspect of the C2 configuration exhibited the highest area values, low roundness values, and large apical diameters. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  7. A mineral-rich extract from the red marine algae Lithothamnion calcareum preserves bone structure and function in female mice on a Western-style diet.

    Science.gov (United States)

    Aslam, Muhammad Nadeem; Kreider, Jaclynn M; Paruchuri, Tejaswi; Bhagavathula, Narasimharao; DaSilva, Marissa; Zernicke, Ronald F; Goldstein, Steven A; Varani, James

    2010-04-01

    The purpose of this study was to determine whether a mineral-rich extract derived from the red marine algae Lithothamnion calcareum could be used as a dietary supplement for prevention of bone mineral loss. Sixty C57BL/6 mice were divided into three groups based on diet: the first group received a high-fat Western-style diet (HFWD), the second group was fed the same HFWD along with the mineral-rich extract included as a dietary supplement, and the third group was used as a control and was fed a low-fat rodent chow diet (AIN76A). Mice were maintained on the respective diets for 15 months. Then, long bones (femora and tibiae) from both males and females were analyzed by three-dimensional micro-computed tomography (micro-CT) and (bones from female mice) concomitantly assessed in bone strength studies. Tartrate-resistant acid phosphatase (TRAP), osteocalcin, and N-terminal peptide of type I procollagen (PINP) were assessed in plasma samples obtained from female mice at the time of sacrifice. To summarize, female mice on the HFWD had reduced bone mineralization and reduced bone strength relative to female mice on the low-fat chow diet. The bone defects in female mice on the HFWD were overcome in the presence of the mineral-rich supplement. In fact, female mice receiving the mineral-rich supplement in the HFWD had better bone structure/function than did female mice on the low-fat chow diet. Female mice on the mineral-supplemented HFWD had higher plasma levels of TRAP than mice of the other groups. There were no differences in the other two markers. Male mice showed little diet-specific differences by micro-CT.

  8. Timing of growth hormone treatment affects trabecular bone microarchitecture and mineralization in growth hormone deficient mice.

    Science.gov (United States)

    Kristensen, Erika; Hallgrímsson, Benedikt; Morck, Douglas W; Boyd, Steven K

    2010-08-01

    Growth hormone (GH) is essential in the development of bone mass, and a growth hormone deficiency (GHD) in childhood is frequently treated with daily injections of GH. It is not clear what effect GHD and its treatment has on bone. It was hypothesized that GHD would result in impaired microarchitecture, and an early onset of treatment would result in a better recovery than late onset. Growth hormone deficient homozygous (lit/lit) mice of both sexes were divided into two treatment groups receiving daily injections of GH, starting at an early (21 days of age) or a late time point (35 days of age, corresponding to the end of puberty). A group of heterozygous mice with normal levels of growth hormone served as controls. In vivo micro-computed tomography scans of the fourth lumbar vertebra were obtained at five time points between 21 and 60 days of age, and trabecular morphology and volumetric BMD were analyzed to determine the effects of GH on bone microarchitecture. Early GH treatment led to significant improvements in bone volume ratio (p=0.006), tissue mineral density (p=0.005), and structure model index (p=0.004) by the study endpoint (day 60), with no detected change in trabecular thickness. Trabecular number increased and trabecular separation decreased in GHD mice regardless of treatment compared to heterozygous mice. This suggests fundamental differences in the structure of trabecular bone in GHD and GH treated mice, reflected by an increased number of thinner trabeculae in these mice compared to heterozygous controls. There were no significant differences between the late treatment group and GHD mice except for connectivity density. Taken together, these results indicate that bone responds to GH treatment initiated before puberty but not to treatment commencing post-puberty, and that GH treatment does not rescue the structure of trabecular bone to that of heterozygous controls. Copyright 2010 Elsevier Inc. All rights reserved.

  9. Laboratory and exterior decay of wood plastic composite boards: voids analysis and computed tomography

    Science.gov (United States)

    Grace Sun; Rebecca E. Ibach; Meghan Faillace; Marek Gnatowski; Jessie A. Glaeser; John Haight

    2016-01-01

    After exposure in the field and laboratory soil block culture testing, the void content of wood–plastic composite (WPC) decking boards was compared to unexposed samples. A void volume analysis was conducted based on calculations of sample density and from micro-computed tomography (microCT) data. It was found that reference WPC contains voids of different sizes from...

  10. Overlapping trisomies for human chromosome 21 orthologs produce similar effects on skull and brain morphology of Dp(16)1Yey and Ts65Dn mice.

    Science.gov (United States)

    Starbuck, John M; Dutka, Tara; Ratliff, Tabetha S; Reeves, Roger H; Richtsmeier, Joan T

    2014-08-01

    Trisomy 21 results in gene-dosage imbalance during embryogenesis and throughout life, ultimately causing multiple anomalies that contribute to the clinical manifestations of Down syndrome. Down syndrome is associated with manifestations of variable severity (e.g., heart anomalies, reduced growth, dental anomalies, shortened life-span). Craniofacial dysmorphology and cognitive dysfunction are consistently observed in all people with Down syndrome. Mouse models are useful for studying the effects of gene-dosage imbalance on development. We investigated quantitative changes in the skull and brain of the Dp(16)1Yey Down syndrome mouse model and compared these mice to Ts65Dn and Ts1Cje mouse models. Three-dimensional micro-computed tomography images of Dp(16)1Yey and euploid mouse crania were morphometrically evaluated. Cerebellar cross-sectional area, Purkinje cell linear density, and granule cell density were evaluated relative to euploid littermates. Skulls of Dp(16)1Yey and Ts65Dn mice displayed similar changes in craniofacial morphology relative to their respective euploid littermates. Trisomy-based differences in brain morphology were also similar in Dp(16)1Yey and Ts65Dn mice. These results validate examination of the genetic basis for craniofacial and brain phenotypes in Dp(16)1Yey mice and suggest that they, like Ts65Dn mice, are valuable tools for modeling the effects of trisomy 21 on development. © 2014 Wiley Periodicals, Inc.

  11. Comparison of micro-computerized tomography and cone-beam computerized tomography in the detection of accessory canals in primary molars

    OpenAIRE

    Acar, Buket; Kamburo?lu, K?van?; Tatar, ?lkan; Ar?kan, Volkan; ?elik, Hakan Hamdi; Y?ksel, Selcen; ?zen, Tuncer

    2015-01-01

    Purpose This study was performed to compare the accuracy of micro-computed tomography (CT) and cone-beam computed tomography (CBCT) in detecting accessory canals in primary molars. Materials and Methods Forty-one extracted human primary first and second molars were embedded in wax blocks and scanned using micro-CT and CBCT. After the images were taken, the samples were processed using a clearing technique and examined under a stereomicroscope in order to establish the gold standard for this s...

  12. Influence of Heat Treatment of Nickel-Titanium Rotary Endodontic Instruments on Apical Preparation: A Micro-Computed Tomographic Study.

    Science.gov (United States)

    de Almeida, Bernardo Corrêa; Ormiga, Fabíola; de Araújo, Marcos César Pimenta; Lopes, Ricardo Tadeu; Lima, Inayá Corrêa Barbosa; dos Santos, Bernardo Camargo; Gusman, Heloisa

    2015-12-01

    The aim of this study was to make a 3-dimensional comparison of the canal transportation and changes in apical geometry using micro-computed tomographic imaging after canal preparation with K3 (SybronEndo, Orange, CA) and K3XF (SybronEndo) file systems. Twenty-eight mandibular molars were randomly divided into 2 groups according to the rotary system used in instrumentation: K3 or K3XF. The specimens were scanned by micro-computed tomographic imaging before and after instrumentation. Images before and after instrumentation from each group were compared with regard to canal volume, surface area, and structure model index (SMI) (paired t test, P instrumentation, the canals from each group were compared regarding the changes in volume, surface area, SMI, and canal transportation in the last 4 apical mm (t test, P Instrumentation with the 2 rotary systems significantly changed the canal volume, surface area, and SMI (P instrument types concerning these parameters (P > .05). There were no significant differences between the 2 groups with regard to canal transportation in the last 4 apical mm (P > .05). Both rotary systems showed adequate canal preparations with reduced values of canal transportation. Heat treatment did not influence changes in root canal geometry in the apical region. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  13. Micro-positron emission tomography/contrast-enhanced computed tomography imaging of orthotopic pancreatic tumor-bearing mice using the αvβ₃ integrin tracer ⁶⁴Cu-labeled cyclam-RAFT-c(-RGDfK-)₄.

    Science.gov (United States)

    Aung, Winn; Jin, Zhao-Hui; Furukawa, Takako; Claron, Michael; Boturyn, Didier; Sogawa, Chizuru; Tsuji, Atsushi B; Wakizaka, Hidekatsu; Fukumura, Toshimitsu; Fujibayashi, Yasuhisa; Dumy, Pascal; Saga, Tsuneo

    2013-09-01

    The purpose of this study was to develop a clinically relevant orthotopic xenotransplantation model of pancreatic cancer and to perform a preclinical evaluation of a new positron emission tomography (PET) imaging probe, ⁶⁴Cu-labeled cyclam-RAFT-c(-RGDfK-)₄ peptide (⁶⁴Cu-RAFT-RGD), using this model. Varying degrees of αvβ₃ integrin expression in several human pancreatic cancer cell lines were examined by flow cytometry and Western blotting. The cell line BxPC-3, which is stably transfected with a red fluorescence protein (RFP), was used for surgical orthotopic implantation. Orthotopic xenograft was established in the pancreas of recipient nude mice. An in vivo probe biodistribution and receptor blocking study, preclinical PET imaging coregistered with contrast-enhanced computed tomography (CECT) comparing ⁶⁴Cu-RAFT-RGD and ¹⁸F-fluoro-2-deoxy-d-glucose (¹⁸F-FDG) accumulation in tumor, postimaging autoradiography, and histologic and immunohistochemical examinations were done. Biodistribution evaluation with a blocking study confirmed that efficient binding of probe to tumor is highly αvβ₃ integrin specific. ⁶⁴Cu-RAFT-RGD PET combined with CECT provided for precise and easy detection of cancer lesions. Autoradiography, histologic, and immunohistochemical examinations confirmed the accumulation of ⁶⁴Cu-RAFT-RGD in tumor versus nontumor tissues. In comparative PET studies, ⁶⁴Cu-RAFT-RGD accumulation provided better tumor contrast to background than ¹⁸F-FDG. Our results suggest that ⁶⁴Cu-RAFT-RGD PET imaging is potentially applicable for the diagnosis of αvβ₃ integrin-expressing pancreatic tumors.

  14. Micro–Positron Emission Tomography/Contrast-Enhanced Computed Tomography Imaging of Orthotopic Pancreatic Tumor–Bearing Mice Using the αvβ3 Integrin Tracer 64Cu-Labeled Cyclam-RAFT-c(-RGDfK-4

    Directory of Open Access Journals (Sweden)

    Winn Aung

    2013-09-01

    Full Text Available The purpose of this study was to develop a clinically relevant orthotopic xenotransplantation model of pancreatic cancer and to perform a preclinical evaluation of a new positron emission tomography (PET imaging probe, 64Cu-labeled cyclam-RAFT-c(-RGDfK-4 peptide (64Cu-RAFT-RGD, using this model. Varying degrees of αvβ3 integrin expression in several human pancreatic cancer cell lines were examined by flow cytometry and Western blotting. The cell line BxPC-3, which is stably transfected with a red fluorescence protein (RFP, was used for surgical orthotopic implantation. Orthotopic xenograft was established in the pancreas of recipient nude mice. An in vivo probe biodistribution and receptor blocking study, preclinical PET imaging coregistered with contrast-enhanced computed tomography (CECT comparing 64Cu-RAFT-RGD and 18F-fluoro-2-deoxy-D-glucose (18F-FDG accumulation in tumor, postimaging autoradiography, and histologic and immunohistochemical examinations were done. Biodistribution evaluation with a blocking study confirmed that efficient binding of probe to tumor is highly αvβ3 integrin specific. 64Cu-RAFT-RGD PET combined with CECT provided for precise and easy detection of cancer lesions. Autoradiography, histologic, and immunohistochemical examinations confirmed the accumulation of 64Cu-RAFT-RGD in tumor versus nontumor tissues. In comparative PET studies, 64Cu-RAFT-RGD accumulation provided better tumor contrast to background than 18F-FDG. Our results suggest that 64Cu-RAFT-RGD PET imaging is potentially applicable for the diagnosis of αvβ3 integrin–expressing pancreatic tumors.

  15. Non-invasive retinal imaging in mice with fluorescent Scanning Laser Ophthalmoscopy and Fourier Domain Optical Coherence Tomography

    OpenAIRE

    Hossein-Javaheri, Nima

    2010-01-01

    Visualization of the internal structures of the retina is critical for clinical diagnosis and monitoring of pathology as well as for medical research investigating the root causes of retinal degeneration. The aim of this thesis is to develop multi-modal non-invasive imaging technology for studying retinal degeneration and gene therapy in mice. We have constructed a FD-OCT prototype and combined it with a Scanning Laser Ophthalmoscope (SLO) to permit real time alignment of the retinal field of...

  16. Extermination Of Uranium Isotopes Composition Using A Micro Computer With An IEEE-488 Interface For Mass Spectrometer Analysis

    International Nuclear Information System (INIS)

    Prajitno; Taftazani, Agus; Yusuf

    1996-01-01

    A mass spectrometry method can be used to make qualitative or quantitative analysis. For qualitative analysis, identification of unknown materials by a Mass Spectrometer requires definite assignment of mass number to peak on chart. In quantitative analysis, a mass spectrometer is used to determine isotope composition material in the sample. Analysis system of a Mass Spectrometer possession of PPNY-BATAN based on comparison ion current intensity which enter the collector, and have been used to analyse isotope composition. Calculation of isotope composition have been manually done. To increase the performance and to avoid manual data processing, a micro computer and IEEE-488 interface have been installed, also software packaged has been made. So that the determination of the isotope composition of material in the sample will be faster and more efficient. Tile accuracy of analysis using this program on sample standard U 3 O 8 NBS 010 is between 93,87% - 99,98%

  17. Preexisting Dentinal Microcracks in Nonendodontically Treated Teeth: An Ex Vivo Micro-computed Tomographic Analysis.

    Science.gov (United States)

    PradeepKumar, Angambakkam Rajasekaran; Shemesh, Hagay; Chang, Jeffrey Wen-Wei; Bhowmik, Ahendita; Sibi, Swamy; Gopikrishna, Velayutham; Lakshmi-Narayanan, Lakshmikanthanbharathi; Kishen, Anil

    2017-06-01

    This study evaluated the prevalence, location, and pattern of preexisting dentinal microcracks in roots of extracted teeth without endodontic treatment in patients from 2 age groups using micro-computed tomographic imaging. Six hundred thirty-three nonendodontically treated teeth extracted using an atraumatic procedure because of reasons unrelated to this study were collected and divided based on the patient age. Teeth were scanned with micro-computed tomographic imaging (resolution of 26.7 μm) to examine the presence of preexisting dentinal microcracks in roots. The characteristic features of preexisting dentinal microcracks determined were location, extent, length, and coronoapical distribution. Chi-square bivariate analysis was performed to assess the association between various parameters. Forty-five of 633 nonendodontically treated teeth exhibited preexisting microcracks in roots with a prevalence of 7.1%. The prevalence of preexisting microcracks was found to be 8.3% in older patients (40-70 years) compared with 3.7% in younger patients (20-39 years) (P < .050). A significant association was found between the preexisting microcracks in mandibular teeth (10.3%) when compared with maxillary teeth (2.9%) (P < .001). All preexisting microcracks were located mesiodistally; 66% occurred in the cervical and middle thirds of root. Only 33% of the preexisting microcracks were complete in nature, showing canal involvement. Complete dentinal microcracks exhibited a mean length of 6.9 mm, whereas incomplete cracks had a mean length of 3.75 mm (P < .001). Preexisting dentinal microcracks in roots of nonendodontically treated teeth occurred more often in older patients (40-70 years) in the mesiodistal direction. They were predominantly found in the cervical and middle thirds of root and were more likely to be incomplete in nature. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  18. Preparation and biodistribution in mice of ( sup 11 C)carfentanil; A radiopharmaceutical for studying brain. mu. -opioid receptors by positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Saji, Hideo; Tsutsumi, Daisuke; Iida, Yasuhiko; Yokoyama, Akira (Kyoto Univ. (Japan). Faculty of Pharmaceutical Science); Magata, Yasuhiro; Konishi, Junji

    1992-02-01

    A potent {mu}-opioid agonist, ({sup 11}C)carfentanil, was prepared by the methylation of carfentanil carboxylic acid with ({sup 11}C)methyl iodide in order to study brain {mu}-opioid receptors by positron emission tomography. Synthesis (including purification) was completed within 25 min and the radiochemical yield was approximately 40%. The radiochemical purity of the product was more than 99% and its specific activity was 3.7-7.4 GBq/{mu}mol. Biodistribution studies performed in mice after intravenous injection showed a high brain uptake and rapid blood clearance, so a high brain/blood ratio of 1.5-1.8 was found from 5 to 30 min. Regional cerebral distribution studies in the mouse showed a significantly higher uptake of ({sup 11}C)carfentanil by the thalamus and striatum than by the cerebellum, with the radioactivity in the striatum disappearing more rapidly than that in the thalamus. Treatment with naloxone significantly reduced the uptake of ({sup 11}C)carfentanil by the thalamus and striatum. These results indicate that ({sup 11}C)carfentanil binds specifically to brain {mu}-opioid receptors. (author).

  19. Evaluation of the Self-Adjusting File system (SAF) for the instrumentation of primary molar root canals: a micro-computed tomographic study.

    Science.gov (United States)

    Kaya, E; Elbay, M; Yiğit, D

    2017-06-01

    The Self-Adjusting File (SAF) system has been recommended for use in permanent teeth since it offers more conservative and effective root-canal preparation when compared to traditional rotary systems. However, no study had evaluated the usage of SAF in primary teeth. The aim of this study was to evaluate and compare the use of SAF, K file (manual instrumentation) and Profile (traditional rotary instrumentation) systems for primary-tooth root-canal preparation in terms of instrumentation time and amounts of dentin removed using micro-computed tomography (μCT) technology. Study Design: The study was conducted with 60 human primary mandibular second molar teeth divided into 3 groups according to instrumentation technique: Group I: SAF (n=20); Group II: K file (n=20); Group III; Profile (n=20). Teeth were embedded in acrylic blocks and scanned with a μCT scanner prior to instrumentation. All distal root canals were prepared up to size 30 for K file,.04/30 for Profile and 2 mm thickness, size 25 for SAF; instrumentation time was recorded for each tooth, and a second μCT scan was performed after instrumentation was complete. Amounts of dentin removed were measured using the three-dimensional images by calculating the difference in root-canal volume before and after preparation. Data was statistically analysed using the Kolmogorov-Smirnov and Kruskal-Wallis tests. Manual instrumentation (K file) resulted in significantly more dentin removal when compared to rotary instrumentation (Profile and SAF), while the SAF system generated significantly less dentin removal than both manual instrumentation (K file) and traditional rotary instrumentation (Profile) (psystems. Within the experimental conditions of the present study, the SAF seems as a useful system for root-canal instrumentation in primary molars because it removed less dentin than other systems, which is especially important for the relatively thin-walled canals of primary teeth, and because it involves less

  20. Study of bone microarchitecture abnormalities in mice through microct due to U and Th chemical contamination

    International Nuclear Information System (INIS)

    Taam, Pedro; Lopes, Ricardo Tadeu; Lima, Inaya

    2009-01-01

    The di calcium phosphate, widely used to manufacture fertilizers and animal ration, is extracted from rock minerals. Some of these rocks, as fluoroapatite and collophanite, had together with the calcium phosphate, traces of elements as Fe, F, Mg, Mn, Th and U. Most of these elements are considered to be proper additives for fertilizers and animal ration. In the same time, the presence of U and Th is inappropriate and potentially harmful. The risks posed are more than radioactive exposure, it is rather chemical contamination and its biological effects, since U and Th have strong chemical affinity with many substances present in live organisms, specially phosphorus. The effects of U and Th in bone microarchiteture are still unknown. The aim of this work was to study bone microarchiteture changes in mice fed with animal ration enriched with uranyl phosphate and thorium nitrate, both compounds present in the nuclear fuel cycle. At regular intervals(24, 72, 120 and 168 hours after beginning of the enriched feeding) subjects were sacrificed, blood and bone samples were collected and U and Th levels measured through wavelength dispersive X ray fluorescence (WDXRF). We present the data of U and Th blood level and microarchiteture evaluation through micro computed tomography (microCT) for each mice studied. The results showed that the intake of U and Th does indeed affect bone porosity. (author)

  1. Study of bone microarchitecture abnormalities in mice through microct due to U and Th chemical contamination

    Energy Technology Data Exchange (ETDEWEB)

    Taam, Pedro; Lopes, Ricardo Tadeu, E-mail: taam@lin.ufrj.b, E-mail: ricardo@lin.ufrj.b [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. Alberto Luiz Coimbra de Pos Graduacao e Pesquisa de Engenharia. Lab. de Instrumentacao Nuclear; Lima, Inaya, E-mail: inaya@lin.ufrj.b [Universidade do Estado do Rio de Janeiro (UERJ), Nova Friburgo, RJ (Brazil). Instituto Politecnico

    2009-07-01

    The di calcium phosphate, widely used to manufacture fertilizers and animal ration, is extracted from rock minerals. Some of these rocks, as fluoroapatite and collophanite, had together with the calcium phosphate, traces of elements as Fe, F, Mg, Mn, Th and U. Most of these elements are considered to be proper additives for fertilizers and animal ration. In the same time, the presence of U and Th is inappropriate and potentially harmful. The risks posed are more than radioactive exposure, it is rather chemical contamination and its biological effects, since U and Th have strong chemical affinity with many substances present in live organisms, specially phosphorus. The effects of U and Th in bone microarchiteture are still unknown. The aim of this work was to study bone microarchiteture changes in mice fed with animal ration enriched with uranyl phosphate and thorium nitrate, both compounds present in the nuclear fuel cycle. At regular intervals(24, 72, 120 and 168 hours after beginning of the enriched feeding) subjects were sacrificed, blood and bone samples were collected and U and Th levels measured through wavelength dispersive X ray fluorescence (WDXRF). We present the data of U and Th blood level and microarchiteture evaluation through micro computed tomography (microCT) for each mice studied. The results showed that the intake of U and Th does indeed affect bone porosity. (author)

  2. NADPH Oxidase Contributes to Resistance against Aggregatibacter actinomycetemcomitans-Induced Periodontitis in Mice.

    Science.gov (United States)

    Bast, Antje; Kubis, Helen; Holtfreter, Birte; Ribback, Silvia; Martin, Heiner; Schreiner, Helen C; Dominik, Malte J; Breitbach, Katrin; Dombrowski, Frank; Kocher, Thomas; Steinmetz, Ivo

    2017-02-01

    Aggregatibacter actinomycetemcomitans is a Gram-negative commensal bacterium of the oral cavity which has been associated with the pathogenesis of periodontitis with severe alveolar bone destruction. The role of host factors such as reactive oxygen and nitrogen intermediates in periodontal A. actinomycetemcomitans infection and progression to periodontitis is still ill-defined. Therefore, this study aimed to analyze the role of NADPH oxidase and inducible nitric oxide synthase (iNOS) in a murine model of A. actinomycetemcomitans-induced periodontitis. NADPH oxidase-deficient (gp91 phox knockout [KO]), iNOS-deficient (iNOS KO), and C57BL/6 wild-type mice were orally infected with A. actinomycetemcomitans and analyzed for bacterial colonization at various time points. Alveolar bone mineral density and alveolar bone volume were quantified by three-dimensional micro-computed tomography, and the degree of tissue inflammation was calculated by histological analyses. At 5 weeks after infection, A. actinomycetemcomitans persisted at significantly higher levels in the murine oral cavities of infected gp91 phox KO mice than in those of iNOS KO and C57BL/6 mice. Concomitantly, alveolar bone mineral density was significantly lower in all three infected groups than in uninfected controls, but with the highest loss of bone density in infected gp91 phox KO mice. Only infected gp91 phox KO mice revealed significant loss of alveolar bone volume and enhanced inflammatory cell infiltration, as well as an increased number of osteoclasts. Our results indicate that NADPH oxidase is important to control A. actinomycetemcomitans infection in the murine oral cavity and to prevent subsequent alveolar bone destruction and osteoclastogenesis. Copyright © 2017 American Society for Microbiology.

  3. Decreased Bone Formation and Osteopenia in Lamin A/C-Deficient Mice

    Science.gov (United States)

    Vidal, Christopher; McCorquodale, Thomas; Herrmann, Markus; Fatkin, Diane; Duque, Gustavo

    2011-01-01

    Age-related bone loss is associated with changes in bone cellularity with characteristically low levels of osteoblastogenesis. The mechanisms that explain these changes remain unclear. Although recent in vitro evidence has suggested a new role for proteins of the nuclear envelope in osteoblastogenesis, the role of these proteins in bone cells differentiation and bone metabolism in vivo remains unknown. In this study, we used the lamin A/C null (Lmna −/−) mice to identify the role of lamin A/C in bone turnover and bone structure in vivo. At three weeks of age, histological and micro computed tomography measurements of femurs in Lmna −/− mice revealed a significant decrease in bone mass and microarchitecture in Lmna −/− mice as compared with their wild type littermates. Furthermore, quantification of cell numbers after normalization with bone surface revealed a significant reduction in osteoblast and osteocyte numbers in Lmna −/− mice compared with their WT littermates. In addition, Lmna −/− mice have significantly lower osteoclast number, which show aberrant changes in their shape and size. Finally, mechanistic analysis demonstrated that absence of lamin A/C is associated with increase expression of MAN-1 a protein of the nuclear envelope closely regulated by lamin A/C, which also colocalizes with Runx2 thus affecting its capacity as osteogenic transcription factor. In summary, these data clearly indicate that the presence of lamin A/C is necessary for normal bone turnover in vivo and that absence of lamin A/C induces low bone turnover osteopenia resembling the cellular changes of age-related bone loss. PMID:21547077

  4. Sclerostin Antibody Treatment Improves the Bone Phenotype of Crtap(-/-) Mice, a Model of Recessive Osteogenesis Imperfecta.

    Science.gov (United States)

    Grafe, Ingo; Alexander, Stefanie; Yang, Tao; Lietman, Caressa; Homan, Erica P; Munivez, Elda; Chen, Yuqing; Jiang, Ming Ming; Bertin, Terry; Dawson, Brian; Asuncion, Franklin; Ke, Hua Zhu; Ominsky, Michael S; Lee, Brendan

    2016-05-01

    Osteogenesis imperfecta (OI) is characterized by low bone mass, poor bone quality, and fractures. Standard treatment for OI patients is limited to bisphosphonates, which only incompletely correct the bone phenotype, and seem to be less effective in adults. Sclerostin-neutralizing antibodies (Scl-Ab) have been shown to be beneficial in animal models of osteoporosis, and dominant OI resulting from mutations in the genes encoding type I collagen. However, Scl-Ab treatment has not been studied in models of recessive OI. Cartilage-associated protein (CRTAP) is involved in posttranslational type I collagen modification, and its loss of function results in recessive OI. In this study, we treated 1-week-old and 6-week-old Crtap(-/-) mice with Scl-Ab for 6 weeks (25 mg/kg, s.c., twice per week), to determine the effects on the bone phenotype in models of "pediatric" and "young adult" recessive OI. Vehicle-treated Crtap(-/-) and wild-type (WT) mice served as controls. Compared with control Crtap(-/-) mice, micro-computed tomography (μCT) analyses showed significant increases in bone volume and improved trabecular microarchitecture in Scl-Ab-treated Crtap(-/-) mice in both age cohorts, in both vertebrae and femurs. Additionally, Scl-Ab improved femoral cortical parameters in both age cohorts. Biomechanical testing showed that Scl-Ab improved parameters of whole-bone strength in Crtap(-/-) mice, with more robust effects in the week 6 to 12 cohort, but did not affect the increased bone brittleness. Additionally, Scl-Ab normalized the increased osteoclast numbers, stimulated bone formation rate (week 6 to 12 cohort only), but did not affect osteocyte density. Overall, our findings suggest that Scl-Ab treatment may be beneficial in the treatment of recessive OI caused by defects in collagen posttranslational modification. © 2015 American Society for Bone and Mineral Research. © 2015 American Society for Bone and Mineral Research.

  5. The ESA Mice in Space (MIS) habitat: effects of cage confinement on neuromusculoskeletal structure and function and stress/behavior using wild-type C57Bl/6JRj mice in a modular science reference model (MSRM) test on ground

    Science.gov (United States)

    Blottner, Dieter; Vico, Laurence; Jamon, D. Berckmansp L. Vicop Y. Liup R. Canceddap M.

    Background: Environmental conditions likely affect physiology and behaviour of mice used for Life Sciences Research on Earth and in Space. Thus, mice habitats with sufficient statistical numbers should be developed for adequate life support and care and that should meet all nesces-sary ethical and scientific requirements needed to successfully perform animal experimentation in Space. Aim of study: We here analysed the effects of cage confinement on the weightbear-ing musculoskeletal system, behaviour and stress of wild-type mice (C57BL/6JRj, 30 g b.wt., total n = 24) housed for 25 days in a prototypical ground-based MSRM (modular science ref-erence module) in the frame of breadboard activities for a fully automated life support habitat called "Mice in Space" (MIS) at the Leuven University, Belgium. Results: Compared with control housing (individually ventilated cages, IVC-mice) the MIS mice revealed no significant changes in soleus muscle size and myofiber distribution (type I vs. II) and quality of bone (3-D microarchitecture and mineralisation of calvaria, spine and femur) determined by confocal and micro-computed tomography. Corticosterone metabolism measured non-invasively (faeces) monitored elevated adrenocortical activity at only start of the MIS cage confinement (day 1). Behavioural tests (i.e., grip strength, rotarod, L/D box, elevated plus-maze, open field, ag-gressiveness) performed subsequently revealed only minor changes in motor performance (MIS vs. controls). Conclusions: The MIS habitat will not, on its own, produce major effects that could confound interpretation of data induced by microgravity exposure on orbit as planned for future biosatellite programmes. Sponsors: ESA-ESTEC, Noordwijk, NL

  6. Terahertz Computed Tomography of NASA Thermal Protection System Materials

    Science.gov (United States)

    Roth, D. J.; Reyes-Rodriguez, S.; Zimdars, D. A.; Rauser, R. W.; Ussery, W. W.

    2011-01-01

    A terahertz axial computed tomography system has been developed that uses time domain measurements in order to form cross-sectional image slices and three-dimensional volume renderings of terahertz-transparent materials. The system can inspect samples as large as 0.0283 cubic meters (1 cubic foot) with no safety concerns as for x-ray computed tomography. In this study, the system is evaluated for its ability to detect and characterize flat bottom holes, drilled holes, and embedded voids in foam materials utilized as thermal protection on the external fuel tanks for the Space Shuttle. X-ray micro-computed tomography was also performed on the samples to compare against the terahertz computed tomography results and better define embedded voids. Limits of detectability based on depth and size for the samples used in this study are loosely defined. Image sharpness and morphology characterization ability for terahertz computed tomography are qualitatively described.

  7. Correlation of X-Ray Computed Tomography with Quantitative Nuclear Magnetic Resonance Methods for Pre-Clinical Measurement of Adipose and Lean Tissues in Living Mice

    Directory of Open Access Journals (Sweden)

    Matthew N. Metzinger

    2014-10-01

    Full Text Available Numerous obesity studies have coupled murine models with non-invasive methods to quantify body composition in longitudinal experiments, including X-ray computed tomography (CT or quantitative nuclear magnetic resonance (QMR. Both microCT and QMR have been separately validated with invasive techniques of adipose tissue quantification, like post-mortem fat extraction and measurement. Here we report a head-to-head study of both protocols using oil phantoms and mouse populations to determine the parameters that best align CT data with that from QMR. First, an in vitro analysis of oil/water mixtures was used to calibrate and assess the overall accuracy of microCT vs. QMR data. Next, experiments were conducted with two cohorts of living mice (either homogenous or heterogeneous by sex, age and genetic backgrounds to assess the microCT imaging technique for adipose tissue segmentation and quantification relative to QMR. Adipose mass values were obtained from microCT data with three different resolutions, after which the data were analyzed with different filter and segmentation settings. Strong linearity was noted between the adipose mass values obtained with microCT and QMR, with optimal parameters and scan conditions reported herein. Lean tissue (muscle, internal organs was also segmented and quantified using the microCT method relative to the analogous QMR values. Overall, the rigorous calibration and validation of the microCT method for murine body composition, relative to QMR, ensures its validity for segmentation, quantification and visualization of both adipose and lean tissues.

  8. The impact of low-magnitude high-frequency vibration on fracture healing is profoundly influenced by the oestrogen status in mice

    Directory of Open Access Journals (Sweden)

    Esther Wehrle

    2015-01-01

    Full Text Available Fracture healing is impaired in aged and osteoporotic individuals. Because adequate mechanical stimuli are able to increase bone formation, one therapeutical approach to treat poorly healing fractures could be the application of whole-body vibration, including low-magnitude high-frequency vibration (LMHFV. We investigated the effects of LMHFV on fracture healing in aged osteoporotic mice. Female C57BL/6NCrl mice (n=96 were either ovariectomised (OVX or sham operated (non-OVX at age 41 weeks. When aged to 49 weeks, all mice received a femur osteotomy that was stabilised using an external fixator. The mice received whole-body vibrations (20 minutes/day with 0.3 g peak-to-peak acceleration and a frequency of 45 Hz. After 10 and 21 days, the osteotomised femurs and intact bones (contra-lateral femurs, lumbar spine were evaluated using bending-testing, micro-computed tomography (μCT, histology and gene expression analyses. LMHFV disturbed fracture healing in aged non-OVX mice, with significantly reduced flexural rigidity (−81% and bone formation (−80% in the callus. Gene expression analyses demonstrated increased oestrogen receptor β (ERβ, encoded by Esr2 and Sost expression in the callus of the vibrated animals, but decreased β-catenin, suggesting that ERβ might mediate these negative effects through inhibition of osteoanabolic Wnt/β-catenin signalling. In contrast, in OVX mice, LMHFV significantly improved callus properties, with increased flexural rigidity (+1398% and bone formation (+637%, which could be abolished by subcutaneous oestrogen application (0.025 mg oestrogen administered in a 90-day-release pellet. On a molecular level, we found an upregulation of ERα in the callus of the vibrated OVX mice, whereas ERβ was unaffected, indicating that ERα might mediate the osteoanabolic response. Our results indicate a major role for oestrogen in the mechanostimulation of fracture healing and imply that LMHFV might only be safe and

  9. Reactive oxygen species on bone mineral density and mechanics in Cu,Zn superoxide dismutase (Sod1) knockout mice

    International Nuclear Information System (INIS)

    Smietana, Michael J.; Arruda, Ellen M.; Faulkner, John A.; Brooks, Susan V.; Larkin, Lisa M.

    2010-01-01

    Research highlights: → Reactive oxygen species (ROS) are considered to be a factor in the onset of a number of age-associated conditions, including loss of BMD. → Cu,Zn-superoxide dismutase (Sod1) deficient mice have increased ROS, reduced bone mineral density, decreased bending stiffness, and decreased strength compared to WT controls. → Increased ROS caused by the deficiency of Sod1, may be responsible for the changes in BMD and bone mechanics and therefore represent an appropriate model for studying mechanisms of age-associated bone loss. -- Abstract: Reactive oxygen species (ROS) play a role in a number of degenerative conditions including osteoporosis. Mice deficient in Cu,Zn-superoxide dismutase (Sod1) (Sod1 -/- mice) have elevated oxidative stress and decreased muscle mass and strength compared to wild-type mice (WT) and appear to have an accelerated muscular aging phenotype. Thus, Sod1 -/- mice may be a good model for evaluating the effects of free radical generation on diseases associated with aging. In this experiment, we tested the hypothesis that the structural integrity of bone as measured by bending stiffness (EI; N/mm 2 ) and strength (MPa) is diminished in Sod1 -/- compared to WT mice. Femurs were obtained from male and female WT and Sod1 -/- mice at 8 months of age and three-point bending tests were used to determine bending stiffness and strength. Bones were also analyzed for bone mineral density (BMD; mg/cc) using micro-computed tomography. Femurs were approximately equal in length across all groups, and there were no significant differences in BMD or EI with respect to gender in either genotype. Although male and female mice demonstrated similar properties within each genotype, Sod1 -/- mice exhibited lower BMD and EI of femurs from both males and females compared with gender matched WT mice. Strength of femurs was also lower in Sod1 -/- mice compared to WT as well as between genders. These data indicate that increased oxidative stress

  10. Deviations of Mesial Root Canals of Mandibular First Molar Teeth at the Apical Third: A Micro-computed Tomographic Study.

    Science.gov (United States)

    Keles, Ali; Keskin, Cangül

    2018-04-19

    The present study aimed to quantitatively analyze apical foramen deviations of mesial root canals of mandibular first molar teeth by means of micro-computed tomographic (micro-CT) imaging. Micro-CT images of the mesial roots of 109 mandibular first molar teeth with independent mesiobuccal (MB) and mesiolingual (ML) root canals were analyzed. The deviations of the apical foramina of the MB, ML, and middle mesial root canals from the anatomic apex were measured. The vertical distance between the apical foramina of each mesial root canal in relation to each other was also calculated. The distances from the apical foramina of the MB, ML, and middle mesial root canals to the anatomic apex of the mesial root were up to 2.51 mm, 3.21 mm, and 5.67 mm, respectively. There was no significant difference between the deviations of MB and ML root canals from each other (P > .05). The middle mesial root canal showed the greatest deviation compared with the MB and ML canals (P < .05). The apical foramina of mesial root canals of mandibular first molar teeth showed greater variations from each other and anatomic apices than previously reported. Clinically, the use of electronic apex locators for the detection of minor apical foramen of each mesial root canal is of the utmost important. Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  11. Detectability of Middle Mesial Root Canal Orifices by Troughing Technique in Mandibular Molars: A Micro-computed Tomographic Study.

    Science.gov (United States)

    Keleş, Ali; Keskin, Cangül

    2017-08-01

    The objective of the present study was to measure the orifice depth of middle mesial canals (MMCs) and evaluate the detectability of orifices using troughing preparation. For this study, 85 mandibular molar teeth with MMCs were selected from the scanned micro-computed tomographic images. The MMCs were categorized, and the distances between the MMC orifices and the cementoenamel junctions (CEJ) were recorded as the depth of the orifice. Data were evaluated with frequency analysis and a chi-square test using SPSS (SPSS Inc, Chicago, IL), and the results indicated a 5% significance level. It was found that 77.41% of the MMC orifices were at the CEJ level, whereas 5.38% and 9.69% of the MMC orifices were detectable within 1-mm and 2-mm depths from the CEJ, respectively. Of the specimens, 7.52% had MMC orifices deeper than 2 mm from the CEJ. Confluent anatomy was the most frequent configuration. No significant relation was detected between the orifice depth and MMC configuration (P > .05). It was concluded that 77.41% of the specimens did not require troughing preparation, the remaining 15.07% would require troughing, and 7.52% could not be accessed even with the troughing preparation. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  12. Maternal environment and craniofacial growth: geometric morphometric analysis of mandibular shape changes with in utero thyroxine overexposure in mice.

    Science.gov (United States)

    Kesterke, Matthew J; Judd, Margaret A; Mooney, Mark P; Siegel, Michael I; Elsalanty, Mohammed; Howie, R Nicole; Weinberg, Seth M; Cray, James J

    2018-07-01

    An estimated 3% of US pregnancies are affected by maternal thyroid dysfunction, with between one and three of every 1000 pregnancies being complicated by overactive maternal thyroid levels. Excess thyroid hormones are linked to neurological impairment and excessive craniofacial variation, affecting both endochondral and intramembranous bone. Using a geometric morphometric approach, this study evaluates the role of in utero thyroxine overexposure on the growth of offspring mandibles in a sample of 241 mice. Canonical variate analysis utilized 16 unilateral mandibular landmarks obtained from 3D micro-computed tomography to assess shape changes between unexposed controls (n = 63) and exposed mice (n = 178). By evaluating shape changes in the mandible among three age groups (15, 20 and 25 days postnatal) and different dosage levels (low, medium and high), this study found that excess maternal thyroxine alters offspring mandibular shape in both age- and dosage-dependent manners. Group differences in overall shape were significant (P < 0.001), and showed major changes in regions of the mandible associated with muscle attachment (coronoid process, gonial angle) and regions of growth largely governed by articulation with the cranial base (condyle) and occlusion (alveolus). These results compliment recent studies demonstrating that maternal thyroxine levels can alter the cranial base and cranial vault of offspring, contributing to a better understanding of both normal and abnormal mandibular development, as well as the medical implications of craniofacial growth and development. © 2018 Anatomical Society.

  13. Suppressor of cytokine signaling 2 (Socs2 deletion protects bone health of mice with DSS-induced inflammatory bowel disease

    Directory of Open Access Journals (Sweden)

    Ross Dobie

    2018-01-01

    Full Text Available Individuals with inflammatory bowel disease (IBD often present with poor bone health. The development of targeted therapies for this bone loss requires a fuller understanding of the underlying cellular mechanisms. Although bone loss in IBD is multifactorial, the altered sensitivity and secretion of growth hormone (GH and insulin-like growth factor-1 (IGF-1 in IBD is understood to be a critical contributing mechanism. The expression of suppressor of cytokine signaling 2 (SOCS2, a well-established negative regulator of GH signaling, is stimulated by proinflammatory cytokines. Therefore, it is likely that SOCS2 expression represents a critical mediator through which proinflammatory cytokines inhibit GH/IGF-1 signaling and decrease bone quality in IBD. Using the dextran sodium sulfate (DSS model of colitis, we reveal that endogenously elevated GH function in the Socs2−/− mouse protects the skeleton from osteopenia. Micro-computed tomography assessment of DSS-treated wild-type (WT mice revealed a worsened trabecular architecture compared to control mice. Specifically, DSS-treated WT mice had significantly decreased bone volume, trabecular thickness and trabecular number, and a resulting increase in trabecular separation. In comparison, the trabecular bone of Socs2-deficient mice was partially protected from the adverse effects of DSS. The reduction in a number of parameters, including bone volume, was less, and no changes were observed in trabecular thickness or separation. This protected phenotype was unlikely to be a consequence of improved mucosal health in the DSS-treated Socs2−/− mice but rather a result of unregulated GH signaling directly on bone. These studies indicate that the absence of SOCS2 is protective against bone loss typical of IBD. This study also provides an improved understanding of the relative effects of GH/IGF-1 signaling on bone health in experimental colitis, information that is essential before these drugs are

  14. THEAP-I: A computer program for thermal hydraulic analysis of a thermally interacting channel bundle of complex geometry. The micro computer version user`s manual

    Energy Technology Data Exchange (ETDEWEB)

    Megaritou, A; Bartzis, J G

    1987-09-01

    In the present report the micro computer version of the code is described. More emphasis is given in the new features of the code (i.e. input data structure). A set of instructions for running in an IBM-AT2 computer with the Microsoft FORTRAN V.4.0 is also included together with a sample problem refering to the Greek Research Reactor.

  15. Relationships between bone strength and bone quality. Three-dimensional imaging analysis in ovariectomized mice

    International Nuclear Information System (INIS)

    Wakabayashi, Suguru; Sakurai, Takashi; Kashima, Isamu

    2004-01-01

    Low-energy trauma resulting in fractures of the distal femur is often observed in elderly patients with osteoporosis; such fractures are often associated with treatment difficulties and poor prognosis. The purpose of this study was to clarify the factors that affect the bone strength of the distal femur. We used ovariectomized mice to demonstrate bone quality factors associated with deterioration of the strength of the distal femur. Ten-week old ICR-strain mice were ovariectomized or sham-ovariectomized. Total bone mineral density (BMD), total bone area, cortical BMD, cortical thickness, and trabecular BMD were measured by peripheral quantitative computed tomography in the distal metaphyseal region of the femora. As three-dimensional architectural parameters, the trabecular number, trabecular thickness (Tb.Th), trabecular separation, and connectivity density were measured in the same region by micro-computed tomography. The maximum load measured by compression testing of the distal metaphyseal region was regarded as the bone strength of each sample. No significant differences in total bone area or in cortical BMD were found between the groups. Bone strength showed the closest relationship with total BMD (r=0.834). Multiple regression analysis demonstrated that total BMD greatly depended on cortical thickness. The addition of Tb.Th to trabecular BMD markedly reflected bone strength (R=0.857), suggesting that Tb.Th affected bone strength more significantly than trabecular BMD. These findings suggested that deterioration of bone strength of the distal femur (metaphysis) was not caused by a reduction in cortical BMD, but was related to reduced cortical thickness, which reduced total BMD, and to trabecular BMD and architecture, in particular to reduced Tb.Th. (author)

  16. Conditional Macrophage Depletion Increases Inflammation and Does Not Inhibit the Development of Osteoarthritis in Obese Macrophage Fas-Induced Apoptosis-Transgenic Mice.

    Science.gov (United States)

    Wu, Chia-Lung; McNeill, Jenna; Goon, Kelsey; Little, Dianne; Kimmerling, Kelly; Huebner, Janet; Kraus, Virginia; Guilak, Farshid

    2017-09-01

    To investigate whether short-term, systemic depletion of macrophages can mitigate osteoarthritis (OA) following injury in the setting of obesity. CSF-1R-GFP+ macrophage Fas-induced apoptosis (MaFIA)-transgenic mice that allow conditional depletion of macrophages were placed on a high-fat diet and underwent surgery to induce knee OA. A small molecule (AP20187) was administrated to deplete macrophages in MaFIA mice. The effects of macrophage depletion on acute joint inflammation, OA severity, and arthritic bone changes were evaluated using histology and micro-computed tomography. Immunohistochemical analysis was performed to identify various immune cells. The levels of serum and synovial fluid cytokines were also measured. Macrophage-depleted mice had significantly fewer M1 and M2 macrophages in the surgically operated joints relative to controls and exhibited decreased osteophyte formation immediately following depletion. Surprisingly, macrophage depletion did not attenuate the severity of OA in obese mice; instead, it induced systemic inflammation and led to a massive infiltration of CD3+ T cells and particularly neutrophils, but not B cells, into the injured joints. Macrophage-depleted mice also demonstrated a markedly increased number of proinflammatory cytokines including granulocyte colony-stimulating factor, interleukin-1β (IL-1β), IL-6, IL-8, and tumor necrosis factor in both serum and joint synovial fluid, although the mice showed a trend toward decreased levels of insulin and leptin in serum after macrophage depletion. Our findings indicate that macrophages are vital for modulating homeostasis of immune cells in the setting of obesity and suggest that more targeted approaches of depleting specific macrophage subtypes may be necessary to mitigate inflammation and OA in the setting of obesity. © 2017, American College of Rheumatology.

  17. Maturation Stage Enamel Malformations in Amtn and Klk4 Null Mice

    Science.gov (United States)

    Nunez, Stephanie M.; Chun, Yong-Hee P.; Ganss, Bernhard; Hu, Yuanyuan; Richardson, Amelia S; Schmitz, James E.; Fajardo, Roberto; Yang, Jie; Hu, Jan C-C.; Simmer, James P.

    2015-01-01

    Amelotin (AMTN) and kallikrein-4 (KLK4) are secreted proteins specialized for enamel biomineralization. We characterized enamel from wild-type, Amtn−/−, Klk4−/−, Amtn+/−Klk4+/− and Amtn−/−Klk4−/− mice to gain insights into AMTN and KLK4 functions during amelogenesis. All of the null mice were healthy and fertile. The mandibular incisors in Amtn−/−, Klk4−/− and Amtn−/−Klk4−/− mice were chalky-white and chipped. No abnormalities except in enamel were observed, and no significant differences were detected in enamel thickness or volume, or in rod decussation. Micro-computed tomography (µCT) maximum intensity projections localized the onset of enamel maturation in wild-type incisors distal to the first molar, but mesial to this position in Amtn−/−, Klk4−/− and Amtn−/−Klk4−/− mice, demonstrating a delay in enamel maturation in Amtn−/− incisors. Micro-CT detected significantly reduced enamel mineral density (2.5 and 2.4 gHA/cm3) in the Klk4−/− and Amtn−/−Klk4−/− mice respectively, compared with wild-type enamel (3.1 gHA/cm3). Backscatter scanning electron microscopy showed that mineral density progressively diminished with enamel depth in the Klk4−/− and Amtn−/−Klk4−/− mice. Knoop hardness of Amtn−/− outer enamel was significantly reduced relative to the wild-type and was not as hard as the middle or inner enamel. Klk4−/− enamel hardness was significantly reduced at all levels, but the outer enamel was significantly harder than the inner and middle enamel. Thus the hardness patterns of the Amtn−/− and Klk4−/− mice were distinctly different, while the Amtn−/−Klk4−/− outer enamel was not as hard as in the Amtn−/− and Klk4−/− mice. We conclude that AMTN and KLK4 function independently, but are both necessary for proper enamel maturation. PMID:26620968

  18. Cell-printing and transfer technology applications for bone defects in mice.

    Science.gov (United States)

    Tsugawa, Junichi; Komaki, Motohiro; Yoshida, Tomoko; Nakahama, Ken-ichi; Amagasa, Teruo; Morita, Ikuo

    2011-10-01

    Bone regeneration therapy based on the delivery of osteogenic factors and/or cells has received a lot of attention in recent years since the discovery of pluripotent stem cells. We reported previously that the implantation of capillary networks engineered ex vivo by the use of cell-printing technology could improve blood perfusion. Here, we developed a new substrate prepared by coating glass with polyethylene glycol (PEG) to create a non-adhesive surface and subsequent photo-lithography to finely tune the adhesive property for efficient cell transfer. We examined the cell-transfer efficiency onto amniotic membrane and bone regenerative efficiency in murine calvarial bone defect. Cell transfer of KUSA-A1 cells (murine osteoblasts) to amniotic membrane was performed for 1 h using the substrates. Cell transfer using the substrate facilitated cell engraftment onto the amniotic membrane compared to that by direct cell inoculation. KUSA-A1 cells transferred onto the amniotic membrane were applied to critical-sized calvarial bone defects in mice. Micro-computed tomography (micro-CT) analysis showed rapid and effective bone formation by the cell-equipped amniotic membrane. These results indicate that the cell-printing and transfer technology used to create the cell-equipped amniotic membrane was beneficial for the cell delivery system. Our findings support the development of a biologically stable and effective bone regeneration therapy. Copyright © 2011 John Wiley & Sons, Ltd.

  19. Polycythemia is associated with bone loss and reduced osteoblast activity in mice.

    Science.gov (United States)

    Oikonomidou, P R; Casu, C; Yang, Z; Crielaard, B; Shim, J H; Rivella, S; Vogiatzi, M G

    2016-04-01

    Increased fragility has been described in humans with polycythemia vera (PV). Herein, we describe an osteoporotic phenotype associated with decreased osteoblast activity in a mouse model of PV and another mouse of polycythemia and elevated circulating erythropoietin (EPO). Our results are important for patients with PV or those treated with recombinant EPO (rEPO). PV and other myeloproliferative syndromes have been recently associated with an increased risk for fractures. However, the presence of osteoporosis in these patients has not been well documented. EPO, a hormone primarily known to stimulate erythropoiesis, has been shown recently to regulate bone homeostasis in mice. The aim of this study was to examine the bone phenotype of a mouse model of PV and compare it to that of animals with polycythemia caused by elevated circulating EPO. Bone mass and remodeling were evaluated by micro-computed tomography and histomorphometry. The JAK2(V617F) knock-in mouse, a model of human PV, manifests polycythemia and low circulating EPO levels. Results from this mouse were compared to wild type (wt) controls and the tg6 transgenic mouse that shows polycythemia caused by increased constitutive expression of EPO. Compared to wt, both JAK2(V617F) and tg6 mice had a decrease in trabecular bone mass. Tg6 mice showed an additional modest decrease in cortical thickness and cortical bone volume per tissue volume (P Polycythemia caused by chronically elevated circulating EPO also results in bone loss, and implications on patients treated with rEPO should be evaluated.

  20. Heme oxygenase-1-mediated autophagy protects against pulmonary endothelial cell death and development of emphysema in cadmium-treated mice

    Science.gov (United States)

    Surolia, Ranu; Karki, Suman; Kim, Hyunki; Yu, Zhihong; Kulkarni, Tejaswini; Mirov, Sergey B.; Carter, A. Brent; Rowe, Steven M.; Matalon, Sadis; Thannickal, Victor J.; Agarwal, Anupam

    2015-01-01

    Pulmonary exposure to cadmium, a major component of cigarette smoke, has a dramatic impact on lung function and the development of emphysema. Cigarette smoke exposure induces heme oxygenase-1 (HO-1), a cytoprotective enzyme. In this study, we employed a truncated mouse model of emphysema by intratracheal instillation of cadmium (CdCl2) solution (0.025% per 1 mg/kg body wt) in HO-1+/+, HO-1−/−, and overexpressing humanized HO-1 bacterial artificial chromosome (hHO-1BAC) mice. We evaluated the role of HO-1 in cadmium-induced emphysema in mice by analyzing histopathology, micro-computed tomography scans, and lung function tests. CdCl2-exposed HO-1−/− mice exhibited more severe emphysema compared with HO-1+/+ or hHO-1BAC mice. Loss of pulmonary endothelial cells (PECs) from the alveolar capillary membrane is recognized to be a target in emphysema. PECs from HO-1+/+, HO-1−/−, and hHO-1BAC were employed to define the underlying molecular mechanism for the protection from emphysema by HO-1. Electron microscopy, expression of autophagic markers (microtubule-associated protein 1B-light chain 3 II, autophagy protein 5, and Beclin1) and apoptotic marker (cleaved caspase 3) suggested induction of autophagy and apoptosis in PECs after CdCl2 treatment. CdCl2-treated HO-1−/− PECs exhibited downregulation of autophagic markers and significantly increased cleaved caspase 3 expression and activity (∼4-fold higher). Moreover, hHO-1BAC PECs demonstrated upregulated autophagy and absence of cleaved caspase 3 expression or activity. Pretreatment of HO-1+/+ PECs with rapamycin induced autophagy and resulted in reduced cell death upon cadmium treatment. Induction of autophagy following CdCl2 treatment was found to be protective from apoptotic cell death. HO-1 induced protective autophagy in PECs and mitigated cadmium-induced emphysema. PMID:26071551

  1. Heme oxygenase-1-mediated autophagy protects against pulmonary endothelial cell death and development of emphysema in cadmium-treated mice.

    Science.gov (United States)

    Surolia, Ranu; Karki, Suman; Kim, Hyunki; Yu, Zhihong; Kulkarni, Tejaswini; Mirov, Sergey B; Carter, A Brent; Rowe, Steven M; Matalon, Sadis; Thannickal, Victor J; Agarwal, Anupam; Antony, Veena B

    2015-08-01

    Pulmonary exposure to cadmium, a major component of cigarette smoke, has a dramatic impact on lung function and the development of emphysema. Cigarette smoke exposure induces heme oxygenase-1 (HO-1), a cytoprotective enzyme. In this study, we employed a truncated mouse model of emphysema by intratracheal instillation of cadmium (CdCl2) solution (0.025% per 1 mg/kg body wt) in HO-1(+/+), HO-1(-/-), and overexpressing humanized HO-1 bacterial artificial chromosome (hHO-1BAC) mice. We evaluated the role of HO-1 in cadmium-induced emphysema in mice by analyzing histopathology, micro-computed tomography scans, and lung function tests. CdCl2-exposed HO-1(-/-) mice exhibited more severe emphysema compared with HO-1(+/+) or hHO-1BAC mice. Loss of pulmonary endothelial cells (PECs) from the alveolar capillary membrane is recognized to be a target in emphysema. PECs from HO-1(+/+), HO-1(-/-), and hHO-1BAC were employed to define the underlying molecular mechanism for the protection from emphysema by HO-1. Electron microscopy, expression of autophagic markers (microtubule-associated protein 1B-light chain 3 II, autophagy protein 5, and Beclin1) and apoptotic marker (cleaved caspase 3) suggested induction of autophagy and apoptosis in PECs after CdCl2 treatment. CdCl2-treated HO-1(-/-) PECs exhibited downregulation of autophagic markers and significantly increased cleaved caspase 3 expression and activity (∼4-fold higher). Moreover, hHO-1BAC PECs demonstrated upregulated autophagy and absence of cleaved caspase 3 expression or activity. Pretreatment of HO-1(+/+) PECs with rapamycin induced autophagy and resulted in reduced cell death upon cadmium treatment. Induction of autophagy following CdCl2 treatment was found to be protective from apoptotic cell death. HO-1 induced protective autophagy in PECs and mitigated cadmium-induced emphysema. Copyright © 2015 the American Physiological Society.

  2. Particle coagulation in molten metal based on three-dimensional analysis of cluster by x-ray micro-computer tomography (CT)

    International Nuclear Information System (INIS)

    Li, Tao; Shimasaki, Shin-ichi; Taniguchi, Shoji; Narita, Shunsuke; Uesugi, Kentaro

    2013-01-01

    Particle coagulation plays a key role in steel refining process to remove inclusions. Many research works focus on the behaviors of particle coagulation. To reveal its mechanism water model experiments have been performed by some researchers including the authors' group. In this paper, experiments of particle coagulation were carried out with molten Al including SiC particles in a mechanically agitated crucible with two baffles. Particle coagulation and formation of clusters were observed on the microscopy images of as-polished samples. Three-dimensional (3D) analysis of the clusters in solidified Al was implemented by X-ray micro CT available at SPring-8. The methods to distinguish clusters on two-dimensional (2D) cross-sectional images were discussed, which were established in the previous works by the present authors' group. The characteristics of the 3D SiC clusters and their 2D cross-sections were analyzed. The statistical ranges of the parameters for 2D clusters were used as criterions to distinguish the clusters on 2D microscopy images from the as-polished samples. The kinetics of SiC particle coagulation was studied by the measured cluster number density and size using our program to distinguish cluster in 2D cross-sectional images according to 3D information (DC-2D-3D). The calculated and experimental results of the SiC particle coagulation in molten Al agree well with each other. (author)

  3. Three-dimensional analysis of the pulp cavity on surface models of molar teeth, using X-ray micro-computed tomography

    DEFF Research Database (Denmark)

    Markvart, Merete; Bjørndal, Lars; Darvann, Tron Andre

    2012-01-01

    . In summary, three-dimensional surface models were made with a high precision; an increased accumulation of mineral deposits was noted in molars with small pulp chambers and combined with the consistent pattern of intra-radicular connections, the potential endodontic treatment complexity is underlined...

  4. Three-dimensional assessment of crestal bone levels at titanium implants with different abutment microstructures and insertion depths using micro-computed tomography.

    Science.gov (United States)

    Becker, Kathrin; Klitzsch, Inka; Stauber, Martin; Schwarz, Frank

    2017-06-01

    To (i) assess the impact of insertion depth and abutment microstructure on the three-dimensional crestal bone-level changes at endosseous titanium implant using μCT and computerized image processing and (ii) to correlate the findings with previously reported histology. Titanium implants (conical abutment connection) were inserted in each hemimandible of n = 6 foxhounds with the implant shoulder (IS) located either in epicrestal (0 mm), supracrestal (+1 mm) or subcrestal (-1 mm) positions and randomly (split-mouth design) connected with machined or partially micro-grooved healing abutments. At 20 weeks, the tissue biopsies were processed for μCT and histological (HI) analyses. The volumetric dehiscence profile around the implants was computed as distance between the implant shoulder (IS) and the most coronal bone-to-implant contact (CBI) using MATLAB. The respective buccal and oral values were averaged, and agreement with the respective IS-CBI scores from HI was assessed using Bland-Altman plots. A median net bone gain was observed for supracrestal insertion depths at both abutment types, but lower bounds of the 75% quartile experienced net bone losses. Epicrestal and subcrestal insertion depths were linked to slight bone losses, and the buccal and oral dehiscences were smaller compared to supracrestal positioning. Bland-Altman plots yielded a moderate agreement of IS-CBI values measured with μCT and HI. The novel image processing method allowed reliable evaluations and pointed to a direct impact of insertion depths on crestal bone-level changes. Additionally, it demonstrated that HI morphometry crucially depends on the chosen cutting position. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Comparing ProFile Vortex to ProTaper Next for the efficacy of removal of root filling material: An ex vivo micro-computed tomography study

    Directory of Open Access Journals (Sweden)

    Emad AlShwaimi

    2018-01-01

    Conclusion: Our findings suggest that PV is as effective as PTN for removal of root canal filling material. Therefore, PV can be considered for use in endodontic retreatment, although more effective files or techniques are still required.

  6. Micro-computed tomography (μCT) as a novel method in ecotoxicology - determination of morphometric and somatic data in rainbow trout (Oncorhynchus mykiss)

    NARCIS (Netherlands)

    Brinkmann, M.; Rizzo, L.Y.; Lammers, Twan Gerardus Gertudis Maria; Gremse, F.; Schiwy, S.; Kiessling, F.; Hollert, H.

    2016-01-01

    Fish are important sentinel organisms for the assessment of water quality and play a central role in ecotoxicological research. Of particular importance to the assessment of health and fitness of fish stocks in response to environmental conditions or pollution are morphometric (e.g. Fulton's

  7. Endogenous Parathyroid Hormone Promotes Fracture Healing by Increasing Expression of BMPR2 through cAMP/PKA/CREB Pathway in Mice

    Directory of Open Access Journals (Sweden)

    Wei Zhou

    2017-06-01

    Full Text Available Background/Aims: Endogenous parathyroid hormone (PTH plays an important role in fracture healing. This study investigated whether endogenous PTH regulates fracture healing by bone morphogenetic protein (BMP and/or the transforming growth factor-β (TGF-β signaling pathway. Methods: Eight-week-old wild-type (WT and PTH-knockout (PTH KO male mice were selected, and models of open right-femoral fracture were constructed. Fracture healing and callus characteristics of mice in the two groups were compared by X-ray, micro-computed tomography, histological, and immunohistochemical examinations. Bone marrow mesenchymal stem cells (BMMSCs of 8-week-old WT and PTHKO male mice were obtained and induced into osteoblasts and chondrocytes. Results: We found that expression levels of Runt-related transcription factor (RUNX2, bone morphogenetic protein-receptor-type Ⅱ (BMPR2, phosphorylated Smad 1/5/8, and phosphorylated cyclic adenosine monophosphate-responsive element binding protein (CREB in the callus of PTHKO mice were significantly decreased, whereas no significant difference in expression of SOX9, TGF-βR2,or pSMAD2/3 was observed between PTHKO and WT mice. Additionally, the activity of osteoblast alkaline phosphatase was low at 7 days post-induction, and was upregulated by addition of PTH or dibutyryl cyclic adenosine monophosphate (dbcAMP to the cell culture. Furthermore, H89 (protein kinase A inhibitoreliminated the simulating effects of PTH and dbcAMP, and a low concentration of cyclic adenosine monophosphate (cAMP was observed in PTHKO mouse BMMSCs. Conclusion: These results suggested that endogenous PTH enhanced BMPR2 expression by a cAMP/PKA/CREB pathway in osteoblasts, and increased RUNX2 expression through transduction of the BMP/pSMAD1/5/8 signaling pathway.

  8. Evaluation of Biomaterials Using Micro-Computerized Tomography

    International Nuclear Information System (INIS)

    Torris, A. T. Arun; Columbus, K. C. Soumya; Saaj, U. S.; Krishnan, Kalliyana V.; Nair, Manitha B.

    2008-01-01

    Micro-computed tomography or Micro-CT is a high resolution, non-invasive, x-ray scanning technique that allows precise three-dimensional imaging and quantification of micro-architectural and structural parameters of objects. Tomographic reconstruction is based on a cone-beam convolution-back-projection algorithm. Micro-architectural and structural parameters such as porosity, surface area to volume ratio, interconnectivity, pore size, wall thickness, anisotropy and cross-section area of biomaterials and bio-specimens such as trabecular bone, polymer scaffold, bio-ceramics and dental restorative were evaluated through imaging and computer aided manipulation of the object scan data sets.

  9. Rapid-throughput skeletal phenotyping of 100 knockout mice identifies 9 new genes that determine bone strength.

    Directory of Open Access Journals (Sweden)

    J H Duncan Bassett

    Full Text Available Osteoporosis is a common polygenic disease and global healthcare priority but its genetic basis remains largely unknown. We report a high-throughput multi-parameter phenotype screen to identify functionally significant skeletal phenotypes in mice generated by the Wellcome Trust Sanger Institute Mouse Genetics Project and discover novel genes that may be involved in the pathogenesis of osteoporosis. The integrated use of primary phenotype data with quantitative x-ray microradiography, micro-computed tomography, statistical approaches and biomechanical testing in 100 unselected knockout mouse strains identified nine new genetic determinants of bone mass and strength. These nine new genes include five whose deletion results in low bone mass and four whose deletion results in high bone mass. None of the nine genes have been implicated previously in skeletal disorders and detailed analysis of the biomechanical consequences of their deletion revealed a novel functional classification of bone structure and strength. The organ-specific and disease-focused strategy described in this study can be applied to any biological system or tractable polygenic disease, thus providing a general basis to define gene function in a system-specific manner. Application of the approach to diseases affecting other physiological systems will help to realize the full potential of the International Mouse Phenotyping Consortium.

  10. Swept-source optical coherence tomography powered by a 1.3-μm vertical cavity surface emitting laser enables 2.3-mm-deep brain imaging in mice in vivo

    Science.gov (United States)

    Choi, Woo June; Wang, Ruikang K.

    2015-10-01

    We report noninvasive, in vivo optical imaging deep within a mouse brain by swept-source optical coherence tomography (SS-OCT), enabled by a 1.3-μm vertical cavity surface emitting laser (VCSEL). VCSEL SS-OCT offers a constant signal sensitivity of 105 dB throughout an entire depth of 4.25 mm in air, ensuring an extended usable imaging depth range of more than 2 mm in turbid biological tissue. Using this approach, we show deep brain imaging in mice with an open-skull cranial window preparation, revealing intact mouse brain anatomy from the superficial cerebral cortex to the deep hippocampus. VCSEL SS-OCT would be applicable to small animal studies for the investigation of deep tissue compartments in living brains where diseases such as dementia and tumor can take their toll.

  11. Dynamic contrast-enhanced micro-CT on mice with mammary carcinoma for the assessment of antiangiogenic therapy response

    Energy Technology Data Exchange (ETDEWEB)

    Eisa, Fabian [University of Erlangen-Nuremberg, Institute of Medical Physics, Erlangen (Germany); University of Erlangen-Nuremberg, Graduate School in Advanced Optical Technologies (SAOT), Erlangen (Germany); Brauweiler, Robert; Hupfer, Martin; Nowak, Tristan; Kalender, Willi A. [University of Erlangen-Nuremberg, Institute of Medical Physics, Erlangen (Germany); Lotz, Laura; Hoffmann, Inge; Dittrich, Ralf; Beckmann, Matthias W. [University of Erlangen-Nuremberg, OB/GYN, University Hospital Erlangen, Erlangen (Germany); Wachter, David [University Hospital Erlangen, Institute of Pathology, Erlangen (Germany); Jost, Gregor; Pietsch, Hubertus [Bayer Pharma AG, Berlin (Germany)

    2012-04-15

    To evaluate the potential of in vivo dynamic contrast-enhanced micro-computed tomography (DCE micro-CT) for the assessment of antiangiogenic drug therapy response of mice with mammary carcinoma. 20 female mice with implanted MCF7 tumours were split into control group and therapy group treated with a known effective antiangiogenic drug. All mice underwent DCE micro-CT for the 3D analysis of functional parameters (relative blood volume [rBV], vascular permeability [K], area under the time-enhancement curve [AUC]) and morphology. All parameters were determined for total, peripheral and central tumour volumes of interest (VOIs). Immunohistochemistry was performed to characterise tumour vascularisation. 3D dose distributions were determined. The mean AUCs were significantly lower in therapy with P values of 0.012, 0.007 and 0.023 for total, peripheral and central tumour VOIs. K and rBV showed significant differences for the peripheral (P{sub per}{sup K} = 0.032, P{sub per}{sup rBV} = 0.029), but not for the total and central tumour VOIs (P{sub total}{sup K} = 0.108, P{sub central}{sup K} = 0.246, P{sub total}{sup rBV} = 0.093, P{sub central}{sup rBV} = 0.136). Mean tumour volume was significantly smaller in therapy (P{sub in} {sub vivo} = 0.001, P{sub ex} {sub vivo} = 0.005). Histology revealed greater vascularisation in the controls and central tumour necrosis. Doses ranged from 150 to 300 mGy. This study indicates the great potential of DCE micro-CT for early in vivo assessment of antiangiogenic drug therapy response. (orig.)

  12. [18F]FDG and [18F]FLT positron emission tomography imaging following treatment with belinostat in human ovary cancer xenografts in mice

    DEFF Research Database (Denmark)

    Jensen, Mette Munk; Erichsen, Kamille Dumong; Johnbeck, Camilla Bardram

    2013-01-01

    Belinostat is a histone deacetylase inhibitor with anti-tumor effect in several pre-clinical tumor models and clinical trials. The aim of the study was to evaluate changes in cell proliferation and glucose uptake by use of 3'-deoxy-3'-[(18)F]fluorothymidine ([18F]FLT) and 2-deoxy-2-[(18)F]fluoro-......]fluoro-D-glucose ([18F]FDG) positron emission tomography (PET) following treatment with belinostat in ovarian cancer in vivo models....

  13. X-ray imaging characterization of femoral bones in aging mice with osteopetrotic disorder.

    Science.gov (United States)

    Tu, Shu-Ju; Huang, Hong-Wen; Chang, Wei-Jeng

    2015-04-01

    Aging mice with a rare osteopetrotic disorder in which the entire space of femoral bones are filled with trabecular bones are used as our research platform. A complete study is conducted with a micro computed tomography (CT) system to characterize the bone abnormality. Technical assessment of femoral bones includes geometric structure, biomechanical strength, bone mineral density (BMD), and bone mineral content (BMC). Normal aging mice of similar ages are included for comparisons. In our imaging work, we model the trabecular bone as a cylindrical rod and new quantitative which are not previously discussed are developed for advanced analysis, including trabecular segment length, trabecular segment radius, connecting node number, and distribution of trabecular segment radius. We then identified a geometric characteristic in which there are local maximums (0.0049, 0.0119, and 0.0147 mm) in the structure of trabecular segment radius. Our calculations show 343% higher in percent trabecular bone volume at distal-metaphysis; 38% higher in cortical thickness at mid-diaphysis; 11% higher in cortical cross-sectional moment of inertia at mid-diaphysis; 42% higher in cortical thickness at femur neck; 26% higher in cortical cross-sectional moment of inertia at femur neck; 31% and 395% higher in trabecular BMD and BMC at distal-metaphysis; 17% and 27% higher in cortical BMD and BMC at distal-metaphysis; 9% and 53% higher in cortical BMD and BMC at mid-diaphysis; 25% and 64% higher in cortical BMD and BMC at femur neck. Our new quantitative parameters and findings may be extended to evaluate the treatment response for other similar bone disorders. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Computerized tomography

    International Nuclear Information System (INIS)

    Rubashov, I.B.

    1985-01-01

    Operating principle is described for the devices of computerized tomography used in medicine for diagnosis of brain diseases. Computerized tomography is considered as a part of computerized diagnosis, as a part of information science. It is shown that computerized tomography is a real existed field of investigations in medicine and industrial production

  15. Gamma dose effects valuation on micro computing components; Evaluation des effets de la dose gamma sur les composants micro-informatiques

    Energy Technology Data Exchange (ETDEWEB)

    Joffre, F

    1996-12-31

    Robotics in hostile environment raises the problem of micro computing components resistance with gamma radiation cumulated dose. The current aim is to reach a dose of 3000 grays with industrial components. A methodology and an instrumentation adapted to test this type of components have been developed. The aim of this work is to present the advantages and disadvantages bound to the use of industrial components in the presence of gamma radiation. After an analysis of the criteria allowing to justify the technological choices, the different steps which characterize the selection and the assessment methodology used are explained. The irradiation and measures means now operational are mentioned. Moreover, the supply aspects of the chosen components for the design of an industrialized system is taken into account. These selection and assessment components contribute to the development and design of computers for civil nuclear robotics. (O.M.). 7 refs.

  16. Micro-computed Tomographic Analysis of Apical Microcracks before and after Root Canal Preparation by Hand, Rotary, and Reciprocating Instruments at Different Working Lengths.

    Science.gov (United States)

    de Oliveira, Bruna Paloma; Câmara, Andréa Cruz; Duarte, Daniel Amancio; Heck, Richard John; Antonino, Antonio Celso Dantas; Aguiar, Carlos Menezes

    2017-07-01

    This study aimed to compare apical microcrack formation after root canal shaping by hand, rotary, and reciprocating files at different working lengths using micro-computed tomographic analysis. Sixty mandibular incisors were randomly divided into 6 experimental groups (n = 10) according to the systems and working lengths used for the root canal preparation: ProTaper Universal for Hand Use (Dentsply Maillefer, Ballaigues, Switzerland), HyFlex CM (Coltene-Whaledent, Allstetten, Switzerland), and Reciproc (VDW, Munich, Germany) files working at the apical foramen (AF) and 1 mm short of the AF (AF - 1 mm). The teeth were imaged with micro-computed tomographic scanning at an isotropic resolution of 14 μm before and after root canal preparation, and the cross-sectional images generated were assessed to detect microcracks in the apical portion of the roots. Overall, 17 (28.3%) specimens presented microcracks before instrumentation. Apical microcracks were present in 1 (ProTaper Universal for Hand Use), 3 (Hyflex CM), and 2 (Reciproc) specimens when the instrumentation terminated at the AF. When instrumentation was terminated at AF - 1 mm, apical microcracks were detected in 3 (ProTaper Universal for Hand Use) and 4 (Hyflex CM and Reciproc) specimens. All these microcracks detected after root canal preparation were already present before instrumentation, and no new apical microcrack was visualized. For all groups, the number of slices presenting microcracks after root canal preparation was the same as before canal preparation. Root canal shaping with ProTaper Universal for Hand Use, HyFlex CM, and Reciproc systems, regardless of the working length, did not produce apical microcracks. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  17. In vivo evaluation in mice and metabolism in blood of human volunteers of [123I]iodo-PK11195: a possible single-photon emission tomography tracer for visualization of inflammation

    International Nuclear Information System (INIS)

    Dumont, F.; Vos, F. de; Slegers, G.; Versijpt, J.; Jansen, H.M.L.; Dierckx, R.A.; Korf, J.

    1999-01-01

    We report the in vivo evaluation (biodistribution, displacement and metabolization in blood, brain and heart) in mice and the metabolism in blood of human volunteers of iodine-123 labelled 1-(2-iodophenyl)-N-methyl-N-(1-methyl-propyl)-3-isoquinoline carboxamide ([ 123 I]iodo-PK11195), a potential radioligand for visualization of inflammation in humans by single-photon emission tomography. In three series of 18 white mice (NMRI, 20-25 g), the concentration of radioactivity was measured during 48 h. Blood samples were taken, organs and intestines were excised, excretion was collected and all tissues were weighed and counted for radioactivity. The tissue uptake of radioactivity was measured as % of the injected activity/g of tissue. The excretion was expressed as % of the injected activity. Selective tissue uptake was investigated by pretreatment of another three series of 18 mice with cold PK11195 (1 mg/kg body weight). There was an inflow of [ 123 I]iodo-PK11195 in the brain and among peripheral organs, heart (42.3%), lungs (133.5%) and kidneys (18.4%) had the highest uptake. After pretreatment with cold PK11195, there was a decrease in accumulation in the latter three organs, especially in heart (ca. 55%) and lungs (ca. 80%). Metabolite analysis was performed using high-performance liquid chromatography (HPLC). First, the extraction yield of [ 123 I]iodo-PK11195 from blood and tissue was assessed, and found to be >90%. From blank blood samples and organs spiked with [ 123 I]iodo-PK11195 it was concluded that no metabolization took place during the extraction procedure. Analysis of plasma, brain and heart of mice showed that 10 min p.i. [ 123 I]iodo-PK11195 was the only significant (ca. 95%) radioactive compound in brain and heart where-as in plasma other radioactive products (>60%) appeared. Analysis of plasma samples of the three human volunteers at 7, 20, 37 and 50 min p.i. showed that [ 123 I]iodo-PK11195 rapidly decomposes into two polar metabolites, which at

  18. Mechanical Vibration Mitigates the Decrease of Bone Quantity and Bone Quality of Leptin Receptor-Deficient Db/Db Mice by Promoting Bone Formation and Inhibiting Bone Resorption.

    Science.gov (United States)

    Jing, Da; Luo, Erping; Cai, Jing; Tong, Shichao; Zhai, Mingming; Shen, Guanghao; Wang, Xin; Luo, Zhuojing

    2016-09-01

    Leptin, a major hormonal product of adipocytes, is involved in regulating appetite and energy metabolism. Substantial studies have revealed the anabolic actions of leptin on skeletons and bone cells both in vivo and in vitro. Growing evidence has substantiated that leptin receptor-deficient db/db mice exhibit decreased bone mass and impaired bone microstructure despite several conflicting results previously reported. We herein systematically investigated bone microarchitecture, mechanical strength, bone turnover and its potential molecular mechanisms in db/db mice. More importantly, we also explored an effective approach for increasing bone mass in leptin receptor-deficient animals in an easy and noninvasive manner. Our results show that deterioration of trabecular and cortical bone microarchitecture and decreases of skeletal mechanical strength-including maximum load, yield load, stiffness, energy, tissue-level modulus and hardness-in db/db mice were significantly ameliorated by 12-week, whole-body vibration (WBV) with 0.5 g, 45 Hz via micro-computed tomography (μCT), three-point bending, and nanoindentation examinations. Serum biochemical analysis shows that WBV significantly decreased serum tartrate-resistant acid phosphatase 5b (TRACP5b) and CTx-1 levels and also mitigated the reduction of serum osteocalcin (OCN) in db/db mice. Bone histomorphometric analysis confirmed that decreased bone formation-lower mineral apposition rate, bone formation rate, and osteoblast numbers in cancellous bone-in db/db mice were suppressed by WBV. Real-time PCR assays show that WBV mitigated the reductions of tibial alkaline phosphatase (ALP), OCN, Runt-related transcription factor 2 (RUNX2), type I collagen (COL1), BMP2, Wnt3a, Lrp6, and β-catenin mRNA expression, and prevented the increases of tibial sclerostin (SOST), RANK, RANKL, RANL/osteoprotegerin (OPG) gene levels in db/db mice. Our results show that WBV promoted bone quantity and quality in db/db mice with obvious

  19. Heterozygous mutations of FREM1 are associated with an increased risk of isolated metopic craniosynostosis in humans and mice.

    Directory of Open Access Journals (Sweden)

    Lisenka E L M Vissers

    2011-09-01

    Full Text Available The premature fusion of the paired frontal bones results in metopic craniosynostosis (MC and gives rise to the clinical phenotype of trigonocephaly. Deletions of chromosome 9p22.3 are well described as a cause of MC with variably penetrant midface hypoplasia. In order to identify the gene responsible for the trigonocephaly component of the 9p22.3 syndrome, a cohort of 109 patients were assessed by high-resolution arrays and MLPA for copy number variations (CNVs involving 9p22. Five CNVs involving FREM1, all of which were de novo variants, were identified by array-based analyses. The remaining 104 patients with MC were then subjected to targeted FREM1 gene re-sequencing, which identified 3 further mutant alleles, one of which was de novo. Consistent with a pathogenic role, mouse Frem1 mRNA and protein expression was demonstrated in the metopic suture as well as in the pericranium and dura mater. Micro-computed tomography based analyses of the mouse posterior frontal (PF suture, the human metopic suture equivalent, revealed advanced fusion in all mice homozygous for either of two different Frem1 mutant alleles, while heterozygotes exhibited variably penetrant PF suture anomalies. Gene dosage-related penetrance of midfacial hypoplasia was also evident in the Frem1 mutants. These data suggest that CNVs and mutations involving FREM1 can be identified in a significant percentage of people with MC with or without midface hypoplasia. Furthermore, we present Frem1 mutant mice as the first bona fide mouse model of human metopic craniosynostosis and a new model for midfacial hypoplasia.

  20. Comparative investigation of two-dimensional imaging methods and X-ray tomography in the characterization of microstructure

    Energy Technology Data Exchange (ETDEWEB)

    Bacaicoa, Inigo; Luetje, Martin [Kassel Univ. (Germany). Inst. of Materials Engineering, Quality and Reliability; Saelzer, Philipp [Kassel Univ. (Germany). Abt. Materialentwicklung und Verbundwerkstoffe; Umbach, Cristin [Kassel Univ. (Germany). Inst. for Structural Engineering; Brueckner-Foit, Angelika [Kassel Univ. (Germany). Inst. of Materials Engineering; Heim, Hans-Peter [Kassel Univ. (Germany). Plastics Engineering; Middendorf, Bernhard [Kassel Univ. (Germany). Dept. of Building Materials and Construction Chemistry

    2017-11-01

    The microstructural features of three different materials have been quantified by means of 2D image analysis and X-ray micro-computer tomography (CT) and the results were compared to determine the reliability of the 2D analysis in the material characterization. The 3D quantification of shrinkage pores and Fe-rich inclusions of an Al-Si-Cu alloy by X-ray tomography was compared with the statistical analysis of the 2D metallographic pictures and a significant difference in the results was found due to the complex morphology of shrinkage pores and Fe-rich particles. Furthermore, wood particles of a wood-plastic composite were measured by dynamic image analysis and X-ray tomography. Similar results were obtained for the maximum length of the particles, although the results of width differ considerably, which leads to a miscalculation of the particles aspect ratio. Finally, air voids of a foam concrete were investigated by the analysis of the 2D pictures in ImageJ and the results of the 2D circularity were compared with the values of the 3D elongation obtained by micro-computed tomography. The 3D analysis of the air voids in the foam concrete showed a more precise description of the morphology, although the 2D result are in good agreement with the results obtained by X-ray micro-tomography.

  1. Comparative investigation of two-dimensional imaging methods and X-ray tomography in the characterization of microstructure

    International Nuclear Information System (INIS)

    Bacaicoa, Inigo; Luetje, Martin; Saelzer, Philipp; Umbach, Cristin; Brueckner-Foit, Angelika; Heim, Hans-Peter; Middendorf, Bernhard

    2017-01-01

    The microstructural features of three different materials have been quantified by means of 2D image analysis and X-ray micro-computer tomography (CT) and the results were compared to determine the reliability of the 2D analysis in the material characterization. The 3D quantification of shrinkage pores and Fe-rich inclusions of an Al-Si-Cu alloy by X-ray tomography was compared with the statistical analysis of the 2D metallographic pictures and a significant difference in the results was found due to the complex morphology of shrinkage pores and Fe-rich particles. Furthermore, wood particles of a wood-plastic composite were measured by dynamic image analysis and X-ray tomography. Similar results were obtained for the maximum length of the particles, although the results of width differ considerably, which leads to a miscalculation of the particles aspect ratio. Finally, air voids of a foam concrete were investigated by the analysis of the 2D pictures in ImageJ and the results of the 2D circularity were compared with the values of the 3D elongation obtained by micro-computed tomography. The 3D analysis of the air voids in the foam concrete showed a more precise description of the morphology, although the 2D result are in good agreement with the results obtained by X-ray micro-tomography.

  2. Concept of a selective tumour therapy and its evaluation by near-infrared fluorescence imaging and flat-panel volume computed tomography in mice.

    Science.gov (United States)

    Alves, Frauke; Dullin, Christian; Napp, Joanna; Missbach-Guentner, Jeannine; Jannasch, Katharina; Mathejczyk, Julia; Pardo, Luis A; Stühmer, Walter; Tietze, Lutz-F

    2009-05-01

    Conventional chemotherapy of cancer has its limitations, especially in advanced and disseminated disease and suffers from lack of specificity. This results in a poor therapeutic index and considerable toxicity to normal organs. Therefore, many efforts are made to develop novel therapeutic tools against cancer with the aim of selectively targeting the drug to the tumour site. Drug delivery strategies fundamentally rely on the identification of good-quality biomarkers, allowing unequivocal discrimination between cancer and healthy tissue. At present, antibodies or antibody fragments have clearly proven their value as carrier molecules specific for a tumour-associated molecular marker. This present review draws attention to the use of near-infrared fluorescence (NIRF) imaging to investigate binding specificity and kinetics of carrier molecules such as monoclonal antibodies. In addition, flat-panel volume computed tomography (fpVCT) will be presented to monitor anatomical structures in tumour mouse models over time in a non-invasive manner. Each imaging device sheds light on a different aspect; functional imaging is applied to optimise the dose schedule and the concept of selective tumour therapies, whereas anatomical imaging assesses preclinically the efficacy of novel tumour therapies. Both imaging techniques in combination allow the visualisation of functional information obtained by NIRF imaging within an adequate anatomic framework.

  3. The impact of low-magnitude high-frequency vibration on fracture healing is profoundly influenced by the oestrogen status in mice.

    Science.gov (United States)

    Wehrle, Esther; Liedert, Astrid; Heilmann, Aline; Wehner, Tim; Bindl, Ronny; Fischer, Lena; Haffner-Luntzer, Melanie; Jakob, Franz; Schinke, Thorsten; Amling, Michael; Ignatius, Anita

    2015-01-01

    Fracture healing is impaired in aged and osteoporotic individuals. Because adequate mechanical stimuli are able to increase bone formation, one therapeutical approach to treat poorly healing fractures could be the application of whole-body vibration, including low-magnitude high-frequency vibration (LMHFV). We investigated the effects of LMHFV on fracture healing in aged osteoporotic mice. Female C57BL/6NCrl mice (n=96) were either ovariectomised (OVX) or sham operated (non-OVX) at age 41 weeks. When aged to 49 weeks, all mice received a femur osteotomy that was stabilised using an external fixator. The mice received whole-body vibrations (20 minutes/day) with 0.3 G: peak-to-peak acceleration and a frequency of 45 Hz. After 10 and 21 days, the osteotomised femurs and intact bones (contra-lateral femurs, lumbar spine) were evaluated using bending-testing, micro-computed tomography (μCT), histology and gene expression analyses. LMHFV disturbed fracture healing in aged non-OVX mice, with significantly reduced flexural rigidity (-81%) and bone formation (-80%) in the callus. Gene expression analyses demonstrated increased oestrogen receptor β (ERβ, encoded by Esr2) and Sost expression in the callus of the vibrated animals, but decreased β-catenin, suggesting that ERβ might mediate these negative effects through inhibition of osteoanabolic Wnt/β-catenin signalling. In contrast, in OVX mice, LMHFV significantly improved callus properties, with increased flexural rigidity (+1398%) and bone formation (+637%), which could be abolished by subcutaneous oestrogen application (0.025 mg oestrogen administered in a 90-day-release pellet). On a molecular level, we found an upregulation of ERα in the callus of the vibrated OVX mice, whereas ERβ was unaffected, indicating that ERα might mediate the osteoanabolic response. Our results indicate a major role for oestrogen in the mechanostimulation of fracture healing and imply that LMHFV might only be safe and effective in

  4. Amifostine Analog, DRDE-30, Attenuates Bleomycin-Induced Pulmonary Fibrosis in Mice

    Directory of Open Access Journals (Sweden)

    Aastha Arora

    2018-04-01

    Full Text Available Bleomycin (BLM is an effective curative option in the management of several malignancies including pleural effusions; but pulmonary toxicity, comprising of pneumonitis and fibrosis, poses challenge in its use as a front-line chemotherapeutic. Although Amifostine has been found to protect lungs from the toxic effects of radiation and BLM, its application is limited due to associated toxicity and unfavorable route of administration. Therefore, there is a need for selective, potent, and safe anti-fibrotic drugs. The current study was undertaken to assess the protective effects of DRDE-30, an analog of Amifostine, on BLM-induced lung injury in C57BL/6 mice. Whole body micro- computed tomography (CT was used to non-invasively observe tissue damage, while broncheo-alveolar lavage fluid (BALF and lung tissues were assessed for oxidative damage, inflammation and fibrosis. Changes in the lung density revealed by micro-CT suggested protection against BLM-induced lung injury by DRDE-30, which correlated well with changes in lung morphology and histopathology. DRDE-30 significantly blunted BLM-induced oxidative stress, inflammation and fibrosis in the lungs evidenced by reduced oxidative damage, endothelial barrier dysfunction, Myeloperoxidase (MPO activity, pro-inflammatory cytokine release and protection of tissue architecture, that could be linked to enhanced anti-oxidant defense system and suppression of redox-sensitive pro-inflammatory signaling cascades. DRDE-30 decreased the BLM-induced augmentation in BALF TGF-β and lung hydroxyproline levels, as well as reduced the expression of the mesenchymal marker α-smooth muscle actin (α-SMA, suggesting the suppression of epithelial to mesenchymal transition (EMT as one of its anti-fibrotic effects. The results demonstrate that the Amifostine analog, DRDE-30, ameliorates the oxidative injury and lung fibrosis induced by BLM and strengthen its potential use as an adjuvant in alleviating the side effects of

  5. Bone up: craniomandibular development and hard-tissue biomineralization in neonate mice.

    Science.gov (United States)

    Thompson, Khari D; Weiss-Bilka, Holly E; McGough, Elizabeth B; Ravosa, Matthew J

    2017-10-01

    The presence of regional variation in the osteogenic abilities of cranial bones underscores the fact that the mechanobiology of the mammalian skull is more complex than previously recognized. However, the relationship between patterns of cranial bone formation and biomineralization remains incompletely understood. In four strains of mice, micro-computed tomography was used to measure tissue mineral density during perinatal development in three skull regions (calvarium, basicranium, mandible) noted for variation in loading environment, embryological origin, and ossification mode. Biomineralization levels increased during perinatal ontogeny in the mandible and calvarium, but did not increase in the basicranium. Tissue mineral density levels also varied intracranially, with density in the mandible being highest, in the basicranium intermediate, and in the calvarium lowest. Perinatal increases in, and elevated levels of, mandibular biomineralization appear related to the impending postweaning need to resist elevated masticatory stresses. Similarly, perinatal increases in calvarial biomineralization may be linked to ongoing brain expansion, which is known to stimulate sutural bone formation in this region. The lack of perinatal increase in basicranial biomineralization could be a result of earlier developmental maturity in the cranial base relative to other skull regions due to its role in supporting the brain's mass throughout ontogeny. These results suggest that biomineralization levels and age-related trajectories throughout the skull are influenced by the functional environment and ontogenetic processes affecting each region, e.g., onset of masticatory loads in the mandible, whereas variation in embryology and ossification mode may only have secondary effects on patterns of biomineralization. Knowledge of perinatal variation in tissue mineral density, and of normal cranial bone formation early in development, may benefit clinical therapies aiming to correct

  6. Effect of alendronate on post-traumatic osteoarthritis induced by anterior cruciate ligament rupture in mice.

    Science.gov (United States)

    Khorasani, Mohammad S; Diko, Sindi; Hsia, Allison W; Anderson, Matthew J; Genetos, Damian C; Haudenschild, Dominik R; Christiansen, Blaine A

    2015-02-16

    Previous studies in animal models of osteoarthritis suggest that alendronate (ALN) has antiresorptive and chondroprotective effects, and can reduce osteophyte formation. However, these studies used non-physiologic injury methods, and did not investigate early time points during which bone is rapidly remodeled prior to cartilage degeneration. The current study utilized a non-invasive model of knee injury in mice to investigate the effect of ALN treatment on subchondral bone changes, articular cartilage degeneration, and osteophyte formation following injury. Non-invasive knee injury via tibial compression overload or sham injury was performed on a total of 90 mice. Mice were treated with twice weekly subcutaneous injections of low-dose ALN (40 μg/kg/dose), high-dose ALN (1,000 μg/kg/dose), or vehicle, starting immediately after injury until sacrifice at 7, 14 or 56 days. Trabecular bone of the femoral epiphysis, subchondral cortical bone, and osteophyte volume were quantified using micro-computed tomography (μCT). Whole-joint histology was performed at all time points to analyze articular cartilage and joint degeneration. Blood was collected at sacrifice, and serum was analyzed for biomarkers of bone formation and resorption. μCT analysis revealed significant loss of trabecular bone from the femoral epiphysis 7 and 14 days post-injury, which was effectively prevented by high-dose ALN treatment. High-dose ALN treatment was also able to reduce subchondral bone thickening 56 days post-injury, and was able to partially preserve articular cartilage 14 days post-injury. However, ALN treatment was not able to reduce osteophyte formation at 56 days post-injury, nor was it able to prevent articular cartilage and joint degeneration at this time point. Analysis of serum biomarkers revealed an increase in bone resorption at 7 and 14 days post-injury, with no change in bone formation at any time points. High-dose ALN treatment was able to prevent early trabecular

  7. Effect of Post Space Preparation on Apical Obturation Quality of Teeth Obturated with Different Techniques: A Micro-computed Tomographic Study.

    Science.gov (United States)

    Küçükkaya Eren, Selen; Askerbeyli Örs, Sevinc; Yılmaz, Zeliha

    2017-07-01

    The purpose of this study was to evaluate the obturation quality of root canals filled with different techniques and to determine whether post space preparation had an effect on the quality of apical obturation using micro-computed tomographic (micro-CT) imaging. The root canals of 30 human mandibular premolar teeth were instrumented, and the specimens were divided into 3 groups according to the obturation technique used: cold lateral compaction (CLC), warm vertical compaction (WVC), or single-cone (SC) techniques. The specimens were stored at 37°C and 100% humidity for 1 week. Then, the coronal root filling material was removed in order to create a post space. Micro-CT scans were performed before and after post space preparation for the volumetric analysis of voids and filling materials. Data were analyzed using repeated-measures analysis of variance and Bonferroni tests. The CLC and SC groups showed a significantly greater percentage volume of voids than the WVC group (P space preparation (P > .05). The post space preparation caused a significant increase in the percentage volume of voids in the CLC and SC groups (P space preparation (P > .05). No root fillings were void free. The WVC group presented the best obturation quality. The post space preparation negatively influenced the apical integrity of the filling materials in the CLC and SC groups, whereas it had no significant effect in the WVC group. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  8. An energy-based beam hardening model in tomography

    International Nuclear Information System (INIS)

    Casteele, E van de; Dyck, D van; Sijbers, J; Raman, E

    2002-01-01

    As a consequence of the polychromatic x-ray source, used in micro-computer tomography (μCT) and in medical CT, the attenuation is no longer a linear function of absorber thickness. If this nonlinear beam hardening effect is not compensated, the reconstructed images will be corrupted by cupping artefacts. In this paper, a bimodal energy model for the detected energy spectrum is presented, which can be used for reduction of artefacts caused by beam hardening in well-specified conditions. Based on the combination of the spectrum of the source and the detector efficiency, the assumption is made that there are two dominant energies which can describe the system. The validity of the proposed model is examined by fitting the model to the experimental datapoints obtained on a microtomograph for different materials and source voltages

  9. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Sinuses Computed tomography (CT) of the sinuses ... CT of the Sinuses? What is CT (Computed Tomography) of the Sinuses? Computed tomography, more commonly known ...

  10. Illustrated computer tomography

    International Nuclear Information System (INIS)

    Takahashi, S.

    1983-01-01

    This book provides the following information: basic aspects of computed tomography; atlas of computed tomography of the normal adult; clinical application of computed tomography; and radiotherapy planning and computed tomography

  11. Optical tomography of tissues

    International Nuclear Information System (INIS)

    Zimnyakov, D A; Tuchin, Valerii V

    2002-01-01

    Methods of optical tomography of biological tissues are considered, which include pulse-modulation and frequency-modulation tomography, diffusion tomography with the use of cw radiation sources, optical coherent tomography, speckle-correlation tomography of nonstationary media, and optoacoustic tomography. The method for controlling the optical properties of tissues is studied from the point of view of increasing a probing depth in optical coherent tomography. The modern state and prospects of the development of optical tomography are discussed. (review)

  12. Computed tomography

    International Nuclear Information System (INIS)

    Wells, P.; Davis, J.; Morgan, M.

    1994-01-01

    X-ray or gamma-ray transmission computed tomography (CT) is a powerful non-destructive evaluation (NDE) technique that produces two-dimensional cross-sectional images of an object without the need to physically section it. CT is also known by the acronym CAT, for computerised axial tomography. This review article presents a brief historical perspective on CT, its current status and the underlying physics. The mathematical fundamentals of computed tomography are developed for the simplest transmission CT modality. A description of CT scanner instrumentation is provided with an emphasis on radiation sources and systems. Examples of CT images are shown indicating the range of materials that can be scanned and the spatial and contrast resolutions that may be achieved. Attention is also given to the occurrence, interpretation and minimisation of various image artefacts that may arise. A final brief section is devoted to the principles and potential of a range of more recently developed tomographic modalities including diffraction CT, positron emission CT and seismic tomography. 57 refs., 2 tabs., 14 figs

  13. Doppler Tomography

    Science.gov (United States)

    Marsh, T. R.

    I review the method of Doppler tomography which translates binary-star line profiles taken at a series of orbital phases into a distribution of emission over the binary. I begin with a discussion of the basic principles behind Doppler tomography, including a comparison of the relative merits of maximum entropy regularisation versus filtered back-projection for implementing the inversion. Following this I discuss the issue of noise in Doppler images and possible methods for coping with it. Then I move on to look at the results of Doppler Tomography applied to cataclysmic variable stars. Outstanding successes to date are the discovery of two-arm spiral shocks in cataclysmic variable accretion discs and the probing of the stream/magnetospheric interaction in magnetic cataclysmic variable stars. Doppler tomography has also told us much about the stream/disc interaction in non-magnetic systems and the irradiation of the secondary star in all systems. The latter indirectly reveals such effects as shadowing by the accretion disc or stream. I discuss all of these and finish with some musings on possible future directions for the method. At the end I include a tabulation of Doppler maps published in refereed journals.

  14. The early development of medial coronoid disease in growing Labrador retrivers: Radographic, computed tomographic, necropsy and micro-computed tomographic findings

    NARCIS (Netherlands)

    Lau, S.F.; Wolschrijn, C.F.; Hazewinkel, H.A.W.; Siebelt, M; Voorhout, G.

    2013-01-01

    Abstract Medial coronoid disease (MCD) encompasses lesions of the entire medial coronoid process (MCP), both of the articular cartilage and the subchondral bone. To detect the earliest signs of MCD, radiography and computed tomography were used to monitor the development of MCD in 14 Labrador

  15. Microstructural characterization of dental zinc phosphate cements using combined small angle neutron scattering and microfocus X-ray computed tomography

    Czech Academy of Sciences Publication Activity Database

    Viani, Alberto; Sotiriadis, Konstantinos; Kumpová, Ivana; Mancini, L.; Appavou, M.-S.

    2017-01-01

    Roč. 33, č. 4 (2017), s. 402-417 ISSN 0109-5641 R&D Projects: GA MŠk(CZ) LO1219 Keywords : zinc phosphate cements * small angle neutron scattering * X-ray micro-computed tomography * X-ray powder diffraction * zinc oxide * acid-base cements Subject RIV: JJ - Other Materials OBOR OECD: Composites (including laminates, reinforced plastics, cermets, combined natural and synthetic fibre fabrics Impact factor: 4.070, year: 2016 https://www.sciencedirect.com/science/article/pii/S0109564116305127

  16. Computerized tomography

    International Nuclear Information System (INIS)

    Caille, J.M.; Salamon, G.

    1980-01-01

    As X-ray Ct becomes more commonplace, other techniques of investigation using roughly comparable hardware and software have appeared. Positron-Emission Tomography already provides indispensable physiological and physio-pathological information. Similarly, in the histo-chemical field, Nuclear Magnetic Resonance seems very promising. Some of these new techniques will no doubt shortly be considered as essential as CT in establishing accurate diagnoses non-invasively. (orig./VJ) [de

  17. Computed tomography

    International Nuclear Information System (INIS)

    Andre, M.; Resnick, D.

    1988-01-01

    Computed tomography (CT) has matured into a reliable and prominent tool for study of the muscoloskeletal system. When it was introduced in 1973, it was unique in many ways and posed a challenge to interpretation. It is in these unique features, however, that its advantages lie in comparison with conventional techniques. These advantages will be described in a spectrum of important applications in orthopedics and rheumatology

  18. Effect of whole-body vibration on bone properties in aging mice.

    Science.gov (United States)

    Wenger, Karl H; Freeman, James D; Fulzele, Sadanand; Immel, David M; Powell, Brian D; Molitor, Patrick; Chao, Yuh J; Gao, Hong-Sheng; Elsalanty, Mohammed; Hamrick, Mark W; Isales, Carlos M; Yu, Jack C

    2010-10-01

    Recent studies suggest that whole-body vibration (WBV) can improve measures of bone health for certain clinical conditions and ages. In the elderly, there also is particular interest in assessing the ability of physical interventions such as WBV to improve coordination, strength, and movement speed, which help prevent falls and fractures and maintain ambulation for independent living. The current study evaluated the efficacy of WBV in an aging mouse model. Two levels of vibration--0.5 and 1.5g--were applied at 32Hz to CB57BL/6 male mice (n=9 each) beginning at age 18 months and continuing for 12 weeks, 30 min/day, in a novel pivoting vibration device. Previous reports indicate that bone parameters in these mice begin to decrease substantially at 18 months, equivalent to mid-fifties for humans. Micro-computed tomography (micro-CT) and biomechanical assessments were made in the femur, radius, and lumbar vertebra to determine the effect of these WBV magnitudes and durations in the aging model. Sera also were collected for analysis of bone formation and breakdown markers. Mineralizing surface and cell counts were determined histologically. Bone volume in four regions of the femur did not change significantly, but there was a consistent shift toward higher mean density in the bone density spectrum (BDS), with the two vibration levels producing similar results. This new parameter represents an integral of the conventional density histogram. The amount of high density bone statistically improved in the head, neck, and diaphysis. Biomechanically, there was a trend toward greater stiffness in the 1.5 g group (p=0.139 vs. controls in the radius), and no change in strength. In the lumbar spine, no differences were seen due to vibration. Both vibration groups significantly reduced pyridinoline crosslinks, a collagen breakdown marker. They also significantly increased dynamic mineralization, MS/BS. Furthermore, osteoclasts were most numerous in the 1.5 g group (p≤ 0

  19. Morphometric analysis - Cone beam computed tomography to predict bone quality and quantity.

    Science.gov (United States)

    Hohlweg-Majert, B; Metzger, M C; Kummer, T; Schulze, D

    2011-07-01

    Modified quantitative computed tomography is a method used to predict bone quality and quantify the bone mass of the jaw. The aim of this study was to determine whether bone quantity or quality was detected by cone beam computed tomography (CBCT) combined with image analysis. MATERIALS AND PROCEDURES: Different measurements recorded on two phantoms (Siemens phantom, Comac phantom) were evaluated on images taken with the Somatom VolumeZoom (Siemens Medical Solutions, Erlangen, Germany) and the NewTom 9000 (NIM s.r.l., Verona, Italy) in order to calculate a calibration curve. The spatial relationships of six sample cylinders and the repositioning from four pig skull halves relative to adjacent defined anatomical structures were assessed by means of three-dimensional visualization software. The calibration curves for computer tomography (CT) and cone beam computer tomography (CBCT) using the Siemens phantom showed linear correlation in both modalities between the Hounsfield Units (HU) and bone morphology. A correction factor for CBCT was calculated. Exact information about the micromorphology of the bone cylinders was only available using of micro computer tomography. Cone-beam computer tomography is a suitable choice for analysing bone mass, but, it does not give any information about bone quality. 2010 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  20. Experimental Investigation on X-Ray Micro-Computed Tomography by Phase Retrieval with Born Approximations%基于玻恩近似相位恢复的X射线显微CT实验研究

    Institute of Scientific and Technical Information of China (English)

    陈荣昌; 谢红兰; 杜国浩; 邓彪; 朱佩平; 佟亚军; 王玉丹; 肖体乔

    2010-01-01

    结合同轴X射线相位衬度成像(XPCI)中的Born近似相位恢复法和CT技术,实现了基于单一物像距同轴X射线相位衬度CT(IL-XPCT)投影图像的相位恢复切片重构方法.利用上海光源X射线成像及生物医学应用光束线站的单色光开展模型和生物样品(蝗虫)IL-XPCT研究.对比显示,进行相位恢复后,能获得更好的IL-XPCT重构切片和三维重建图像.实验结果表明,本方法具有用于生物活体样品三维无损成像研究的潜力.

  1. Efficacy of D-RaCe and ProTaper Universal Retreatment NiTi instruments and hand files in removing gutta-percha from curved root canals - a micro-computed tomography study.

    Science.gov (United States)

    Rödig, T; Hausdörfer, T; Konietschke, F; Dullin, C; Hahn, W; Hülsmann, M

    2012-06-01

    To compare the efficacy of two rotary NiTi retreatment systems and Hedström files in removing filling material from curved root canals. Curved root canals of 57 extracted teeth were prepared using FlexMaster instruments and filled with gutta-percha and AH Plus. After determination of root canal curvatures and radii in two directions, the teeth were assigned to three identical groups (n = 19). The root fillings were removed with D-RaCe instruments, ProTaper Universal Retreatment instruments or Hedström files. Pre- and postoperative micro-CT imaging was used to assess the percentage of residual filling material as well as the amount of dentine removal. Working time and procedural errors were recorded. Data were analysed using analysis of covariance and analysis of variance procedures. D-RaCe instruments were significantly more effective than ProTaper Universal Retreatment instruments and Hedström files (P ProTaper group, four instrument fractures and one lateral perforation were observed. Five instrument fractures were recorded for D-RaCe. D-RaCe instruments were associated with significantly less residual filling material than ProTaper Universal Retreatment instruments and hand files. Hedström files removed significantly less dentine than both rotary NiTi systems. Retreatment with rotary NiTi systems resulted in a high incidence of procedural errors. © 2012 International Endodontic Journal.

  2. Microarchitecture of the Augmented Bone Following Sinus Elevation with an Albumin Impregnated Demineralized Freeze-Dried Bone Allograft (BoneAlbumin versus Anorganic Bovine Bone Mineral: A Randomized Prospective Clinical, Histomorphometric, and Micro-Computed Tomography Study

    Directory of Open Access Journals (Sweden)

    Kivovics Márton

    2018-01-01

    Full Text Available Serum albumin has been identified as an endogenous protein that is integral to early bone regeneration. We hypothesized that albumin addition to allografts may result in better bone remodeling than what can be achieved with anorganic xenografts. Sinus elevations were performed at 32 sites of 18 patients with the lateral window technique. Sites either received filling with an anorganic bovine bone mineral (ABBM, BioOss, Geistlich, CH or albumin impregnated allograft (BoneAlbumin, OrthoSera, AT. After 6-months patients received dental implants and 16 bone core biopsy samples were obtained from the ABBM filled, and 16 from the BoneAlbumin augmented sites. The biopsies were examined by histomorphometry and µCT. Percentage of the residual graft in the BoneAlbumin group was 0–12.7%, median 5.4% vs. ABBM 6.3–35.9%, median 16.9%, p < 0.05. Results of the µCT analysis showed that the microarchitecture of the augmented bone in the BoneAlbumin group resembles that of the native maxilla in morphometric parameters Trabecular Pattern Factor and Connectivity. Our data show that while ABBM successfully integrates into the newly formed bone tissue as persisting particles, BoneAlbumin is underway towards complete remodeling with new bone closely resembling that of the intact maxilla.

  3. The enigmatic Otway odd-clawed spider (Progradungula otwayensis Milledge, 1997, Gradungulidae, Araneae: Natural history, first description of the female and micro-computed tomography of the male palpal organ

    Directory of Open Access Journals (Sweden)

    Peter Michalik

    2013-09-01

    Full Text Available The recently described cribellate gradungulid Progradungula otwayensis Milledge, 1997 is endemic to the Great Otway National Park (Victoria, Australia and known from only one male and a few juvenile specimens. In a recent survey we recorded 47 specimens at several localities across the western part of the Great Otway National park. Our field data suggest that this species is dependant on the microclimate in the hollows of old myrtle beech trees since other hollow trees were very much less inhabited. Furthermore, we describe the female for the first time and study the male palpal organ by using X-ray microtomography. The female genitalia are characterized by eight spermathecae which are grouped in two quartets. The spermophor resembles the general organization of gradungulids, but is similar to Kaiya Gray, 1987 by a convoluted appearance within the embolus. The muscle 30 is located in the cymbium and resembles the organization of other non-entelegyne Araneomorphae.

  4. A histomorphometric and micro-computed tomography study of bone regeneration in the maxillary sinus comparing biphasic calcium phosphate and deproteinized cancellous bovine bone in a human split-mouth model

    NARCIS (Netherlands)

    de Lange, G.L.; Overman, J.R.; Farre-Guasch, E.; Korstjens, C.M.; Hartman, B.; Langenbach, G.E.J.; van Duin, M.A.; Klein-Nulend, J.

    2014-01-01

    Objective The gain of mineralized bone was compared between deproteinized bovine bone allograft (DBA) and biphasic calcium phosphate (BCP) for dental implant placement. Study Design Five patients with atrophic maxillae underwent bilateral sinus elevation with DBA (Bio-Oss) and BCP (Straumann

  5. Canola and hydrogenated soybean oils accelerate ectopic bone formation induced by implantation of bone morphogenetic protein in mice

    Directory of Open Access Journals (Sweden)

    Yoko Hashimoto

    2014-01-01

    Full Text Available Canola oil (Can and hydrogenated soybean oil (H2-Soy are commonly used edible oils. However, in contrast to soybean oil (Soy, they shorten the survival of stroke-prone spontaneously hypertensive (SHRSP rats. It has been proposed that the adverse effects of these oils on the kidney and testis are caused at least in part by dihydro-vitamin K (VK 1 in H2-Soy and unidentified component(s in Can. Increased intake of dihydro-VK1 is associated with decreased tissue VK2 levels and bone mineral density in rats and humans, respectively. The aim of the present study was to determine the effects of these oils on bone morphogenetic protein (BMP-induced ectopic bone formation, which is promoted by VK2 deficiency, in relation to the role of VK in the γ-carboxylation of osteocalcin and matrix Gla protein. A crude extract of BMPs was implanted into a gap in the fascia of the femoral muscle in 5-week-old mice maintained on a Soy, Can, or H2-Soy diet. Newly formed bone volume, assessed by three-dimensional X-ray micro-computed tomography and three-dimensional reconstruction imaging for bone, was 4-fold greater in the Can and H2-Soy groups than in the Soy group. The plasma carboxylated osteocalcin (Gla-OC and total OC (Gla-OC plus undercarboxylated osteocalcin [Glu-OC] levels were significantly lower in the Can group than in the Soy group (p < 0.05. However, these levels did not significantly differ between the H2-Soy and Soy groups. The plasma Gla-OC/Glu-OC ratio in the Can and H2-Soy groups was significantly lower (in Can; p = 0.044 or was almost significantly lower (in H2-Soy; p = 0.053 than that in the Soy group. In conclusion, Can and H2-Soy accelerated BMP-induced bone formation in mice to a greater extent than Soy. Further research is required to evaluate whether the difference in accelerated ectopic bone formation is associated with altered levels of VK2 and VK-dependent protein(s among the three dietary groups.

  6. Photoacoustic Tomography

    Science.gov (United States)

    Wang, Lihong V.

    Photoacoustic tomography (PAT) refers to imaging that is based on the photoacoustic effect. Although the photoacoustic effect as a physical phenomenon was first reported on by Alexander Graham Bell in 1880 [1], PAT as an imaging technology was developed only after the advent of ultrasonic transducers, computers, and lasers [2-31]. A review on biomedical photoacoustics is available [32]. The motivation for PAT is to combine optical-absorption contrast with ultrasonic spatial resolution for deep imaging in the optical quasi-diffusive or diffusive regime. In PAT, the tissue is irradiated by usually a short-pulsed laser beam to achieve a thermal and acoustic impulse response (Fig. 19.1). Locally absorbed light is converted into heat, which is further converted to a pressure rise via thermo-elastic expansion. The initial pressure rise - determined by the local optical absorption coefficient (μ â ), fluence (ψ) and other thermal and mechanical properties - propagates as an ultrasonic wave, which is referred to as a photoacoustic wave.

  7. Axial tomography

    International Nuclear Information System (INIS)

    Brueckner, K.A.; Lewis, J.H.

    1979-01-01

    The invention relates to axial tomography, sometimes referred to as cross-sectional x-ray. The apparatus described may utilize the conventional x-ray or ultrasonic source and detector and scanning mechanism for producing the plurality of sets of radiation detector output signals. It has the means for storing the detector output signals in analog form with the signals of one set overlying the signals of another set so that signals resulting from radiation through a zone of the object being examined are summed at a corresponding zone in the storage device, typically an electronic storage tube. The summed signals are read from the storage device with a radially inversely proportional reader producing a second signal for storage, again typically in an electronic storage tube. These signals stored in the second storage device are read with Laplacian relation, with the resultant sigal being a video signal that may be connected to a TV monitor for display of the sectional image. In alternative embodiments, optical film systems and electrostatic systems are utilized. (JTA)

  8. Algorithmic fundamentals of computerized tomography and of transverse analogue tomography

    International Nuclear Information System (INIS)

    Heckmann, K.

    1981-01-01

    Computerized tomography and transverse analogue tomography are two different approaches to the same goal, namely, transverse tomography. The algorithm is discussed and compared. Transverse tomography appears capable of further development, judging by this comparison. (orig.) [de

  9. In-Situ X-ray Tomography Study of Cement Exposed to CO2 Saturated Brine

    DEFF Research Database (Denmark)

    Chavez Panduro, E. A.; Torsæter, M.; Gawel, K.

    2017-01-01

    For successful CO2 storage in underground reservoirs, the potential problem of CO2 leakage needs to be addressed. A profoundly improved understanding of the behavior of fractured cement under realistic subsurface conditions including elevated temperature, high pressure and the presence of CO2...... saturated brine is required. Here, we report in situ X-ray micro computed tomography (μ-CT) studies visualizing the microstructural changes upon exposure of cured Portland cement with an artificially engineered leakage path (cavity) to CO2 saturated brine at high pressure. Carbonation of the bulk cement......, self-healing of the leakage path in the cement specimen, and leaching of CaCO3 were thus directly observed. The precipitation of CaCO3, which is of key importance as a possible healing mechanism of fractured cement, was found to be enhanced in confined regions having limited access to CO2...

  10. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... When the image slices are reassembled by computer software, the result is a very detailed multidimensional view ... Safety Images related to Computed Tomography (CT) - Head Videos related to Computed Tomography (CT) - Head Sponsored by ...

  11. What is Computed Tomography?

    Science.gov (United States)

    ... Imaging Medical X-ray Imaging What is Computed Tomography? Share Tweet Linkedin Pin it More sharing options ... Chest X ray Image back to top Computed Tomography (CT) Although also based on the variable absorption ...

  12. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... Stroke Brain Tumors Computer Tomography (CT) Safety During Pregnancy Head and Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to Computed Tomography (CT) - ...

  13. Review of muon tomography

    International Nuclear Information System (INIS)

    Feng Hanliang; Jiao Xiaojing

    2010-01-01

    As a new detection technology, Muon tomography has some potential benefits, such as being able to form a three- dimensional image, without radiation, low cost, fast detecting etc. Especially, muon tomography will play an important role in detecting nuclear materials. It introduces the theory of Muon tomography, its advantages and the Muon tomography system developed by decision sciences corporation and Los Alamos national laboratory. (authors)

  14. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Head Computed tomography (CT) of the head uses special x-ray ... What is CT Scanning of the Head? Computed tomography, more commonly known as a CT or CAT ...

  15. Emission computed tomography

    International Nuclear Information System (INIS)

    Ott, R.J.

    1986-01-01

    Emission Computed Tomography is a technique used for producing single or multiple cross-sectional images of the distribution of radionuclide labelled agents in vivo. The techniques of Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET) are described with particular regard to the function of the detectors used to produce images and the computer techniques used to build up images. (UK)

  16. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Sinuses Computed tomography (CT) of the sinuses uses special x-ray equipment ... story here Images × Image Gallery Patient undergoing computed tomography (CT) scan. View full size with caption Pediatric Content ...

  17. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Head Computed tomography (CT) of the head uses special x-ray equipment ... story here Images × Image Gallery Patient undergoing computed tomography (CT) scan. View full size with caption Pediatric Content ...

  18. Positron emission tomography

    International Nuclear Information System (INIS)

    Reivich, M.; Alavi, A.

    1985-01-01

    This book contains 24 selections. Some of the titles are: Positron Emission Tomography Instrumentation, Generator Systems for Positron Emitters, Reconstruction Algorithms, Cerebral Glucose Consumption: Methodology and Validation, Cerebral Blood Flow Tomography Using Xenon-133 Inhalation: Methods and Clinical Applications, PET Studies of Stroke, Cardiac Positron Emission Tomography, and Use of PET in Oncology

  19. Turbocharging Quantum Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Blume-Kohout, Robin J. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Gamble, John King [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Nielsen, Erik [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Maunz, Peter Lukas Wilhelm [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Scholten, Travis L. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Rudinger, Kenneth Michael [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2015-01-01

    Quantum tomography is used to characterize quantum operations implemented in quantum information processing (QIP) hardware. Traditionally, state tomography has been used to characterize the quantum state prepared in an initialization procedure, while quantum process tomography is used to characterize dynamical operations on a QIP system. As such, tomography is critical to the development of QIP hardware (since it is necessary both for debugging and validating as-built devices, and its results are used to influence the next generation of devices). But tomography suffers from several critical drawbacks. In this report, we present new research that resolves several of these flaws. We describe a new form of tomography called gate set tomography (GST), which unifies state and process tomography, avoids prior methods critical reliance on precalibrated operations that are not generally available, and can achieve unprecedented accuracies. We report on theory and experimental development of adaptive tomography protocols that achieve far higher fidelity in state reconstruction than non-adaptive methods. Finally, we present a new theoretical and experimental analysis of process tomography on multispin systems, and demonstrate how to more effectively detect and characterize quantum noise using carefully tailored ensembles of input states.

  20. Computed tomography for radiographers

    International Nuclear Information System (INIS)

    Brooker, M.

    1986-01-01

    Computed tomography is regarded by many as a complicated union of sophisticated x-ray equipment and computer technology. This book overcomes these complexities. The rigid technicalities of the machinery and the clinical aspects of computed tomography are discussed including the preparation of patients, both physically and mentally, for scanning. Furthermore, the author also explains how to set up and run a computed tomography department, including advice on how the room should be designed

  1. Meaning of Interior Tomography

    Science.gov (United States)

    Wang, Ge; Yu, Hengyong

    2013-01-01

    The classic imaging geometry for computed tomography is for collection of un-truncated projections and reconstruction of a global image, with the Fourier transform as the theoretical foundation that is intrinsically non-local. Recently, interior tomography research has led to theoretically exact relationships between localities in the projection and image spaces and practically promising reconstruction algorithms. Initially, interior tomography was developed for x-ray computed tomography. Then, it has been elevated as a general imaging principle. Finally, a novel framework known as “omni-tomography” is being developed for grand fusion of multiple imaging modalities, allowing tomographic synchrony of diversified features. PMID:23912256

  2. Single photon emission tomography

    International Nuclear Information System (INIS)

    Buvat, Irene

    2011-09-01

    The objective of this lecture is to present the single photon emission computed tomography (SPECT) imaging technique. Content: 1 - Introduction: anatomic, functional and molecular imaging; Principle and role of functional or molecular imaging; 2 - Radiotracers: chemical and physical constraints, main emitters, radioisotopes production, emitters type and imaging techniques; 3 - Single photon emission computed tomography: gamma cameras and their components, gamma camera specifications, planar single photon imaging characteristics, gamma camera and tomography; 4 - Quantification in single photon emission tomography: attenuation, scattering, un-stationary spatial resolution, partial volume effect, movements, others; 5 - Synthesis and conclusion

  3. Analysis of dental abfractions by optical coherence tomography

    Science.gov (United States)

    Demjan, Enikö; Mărcăuţeanu, Corina; Bratu, Dorin; Sinescu, Cosmin; Negruţiu, Meda; Ionita, Ciprian; Topală, Florin; Hughes, Michael; Bradu, Adrian; Dobre, George; Podoleanu, Adrian Gh.

    2010-02-01

    Aim and objectives. Abfraction is the pathological loss of cervical hard tooth substance caused by biomechanical overload. High horizontal occlusal forces result in large stress concentrations in the cervical region of the teeth. These stresses may be high enough to cause microfractures in the dental hard tissues, eventually resulting in the loss of cervical enamel and dentin. The present study proposes the microstructural characterization of these cervical lesions by en face optical coherence tomography (eFOCT). Material and methods: 31 extracted bicuspids were investigated using eFOCT. 24 teeth derived from patients with active bruxism and occlusal interferences; they presented deep buccal abfractions and variable degrees of occlusal pathological attrition. The other 7 bicuspids were not exposed to occlusal overload and had a normal morphology of the dental crowns. The dental samples were investigated using an eFOCT system operating at 1300 nm (B-scan at 1 Hz and C-scan mode at 2 Hz). The system has a lateral resolution better than 5 μm and a depth resolution of 9 μm in tissue. OCT images were further compared with micro - computer tomography images. Results. The eFOCT investigation of bicuspids with a normal morphology revealed a homogeneous structure of the buccal cervical enamel. The C-scan and B-scan images obtained from the occlusal overloaded bicuspids visualized the wedge-shaped loss of cervical enamel and damage in the microstructure of the underlaying dentin. The high occlusal forces produced a characteristic pattern of large cracks, which reached the tooth surface. Conclusions: eFOCT is a promising imaging method for dental abfractions and it may offer some insight on the etiological mechanism of these noncarious cervical lesions.

  4. Borehole radar diffraction tomography

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Seong Jun; Kim, Jung Ho; Yi, Myeong Jong; Chung, Seung Hwan; Lee, Hee Il [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1997-12-01

    Tomography is widely used as imaging method for determining subsurface structure. Among the reconstruction algorithms for tomographic imaging, travel time tomography is almost applied to imaging subsurface. But isolated small body comparable with the wavelength could not be well recognized by travel time tomography. Other tomographic method are need to improve the imaging process. In the study of this year, diffraction tomography was investigated. The theory for diffraction tomography is based on the 1st-order Born approximation. Multisource holography, which is similar to Kirchihoff migration, is compared with diffraction tomography. To improve 1st-order Born diffraction tomography, two kinds of filter designed from multisource holography and 2-D green function, respectively, applied on the reconstructed image. The algorithm was tested for the numerical modeling data of which algorithm consists of the analytic computation of radar signal in transmitter and receiver regions and 2-D FDM scheme for the propagation of electromagnetic waves in media. The air-filled cavity model to show a typical diffraction pattern was applied to diffraction tomography imaging, and the result shows accurate location and area of cavity. But the calculated object function is not well matched the real object function, because the air-filled cavity model is not satisfied week scattered inhomogeneity for 1st born approximation, and the error term is included in estimating source wavelet from received signals. In spite of the object function error, the diffraction tomography assist for interpretation of subsurface as if conducted with travel time tomography. And the fracture model was tested, 1st born diffraction tomographic image is poor because of limited view angle coverage and violation of week scatter assumption, but the filtered image resolve the fracture somewhat better. The tested diffraction tomography image confirms effectiveness of filter for enhancing resolution. (author). 14

  5. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) is a fast, painless exam that uses special ... the limitations of Children's CT? What is Children's CT? Computed tomography, more commonly known as a CT or CAT ...

  6. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... News Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) ... are the limitations of Children's CT? What is Children's CT? Computed tomography, more commonly known as a ...

  7. Comparison of micro-computerized tomography and cone-beam computerized tomography in the detection of accessory canals in primary molars.

    Science.gov (United States)

    Acar, Buket; Kamburoğlu, Kıvanç; Tatar, İlkan; Arıkan, Volkan; Çelik, Hakan Hamdi; Yüksel, Selcen; Özen, Tuncer

    2015-12-01

    This study was performed to compare the accuracy of micro-computed tomography (CT) and cone-beam computed tomography (CBCT) in detecting accessory canals in primary molars. Forty-one extracted human primary first and second molars were embedded in wax blocks and scanned using micro-CT and CBCT. After the images were taken, the samples were processed using a clearing technique and examined under a stereomicroscope in order to establish the gold standard for this study. The specimens were classified into three groups: maxillary molars, mandibular molars with three canals, and mandibular molars with four canals. Differences between the gold standard and the observations made using the imaging methods were calculated using Spearman's rho correlation coefficient test. The presence of accessory canals in micro-CT images of maxillary and mandibular root canals showed a statistically significant correlation with the stereomicroscopic images used as a gold standard. No statistically significant correlation was found between the CBCT findings and the stereomicroscopic images. Although micro-CT is not suitable for clinical use, it provides more detailed information about minor anatomical structures. However, CBCT is convenient for clinical use but may not be capable of adequately analyzing the internal anatomy of primary teeth.

  8. Comparison of micro-computerized tomography and cone-beam computerized tomography in the detection of accessory canals in primary molars

    Energy Technology Data Exchange (ETDEWEB)

    Acar, Buket; Kamburoglu, Kivanc [Dept. of Dentomaxillofacial Radiology, Faculty of Dentistry, Ankara University, Ankara (Turkmenistan); Tatar, Ilkan [Dept. of Anatomy, Faculty of Medicine, Hacettepe University, Ankara (Turkmenistan); Arikan, Volkan [Dept. of Anatomy, Faculty of Medicine, Hacettepe University, Ankara (Turkmenistan); Celik, Hakan Hamid [Dept. of Pediatric Dentistry, Faculty of Dentistry, Kirikkale Unversity, Ankara (Turkmenistan); Yuksel, Selcen [Dept. of Biostatistics, Faculty of Medicine, Yildirim Beyazit University, Ankara (Turkmenistan); Ozen, Tuncer [Dept. of Dentomaxillofacial Radiology, Gulhane Military Hospital, Dental Clinics, Ankara (Turkmenistan)

    2015-12-15

    This study was performed to compare the accuracy of micro-computed tomography (CT) and cone-beam computed tomography (CBCT) in detecting accessory canals in primary molars. Forty-one extracted human primary first and second molars were embedded in wax blocks and scanned using micro-CT and CBCT. After the images were taken, the samples were processed using a clearing technique and examined under a stereomicroscope in order to establish the gold standard for this study. The specimens were classified into three groups: maxillary molars, mandibular molars with three canals, and mandibular molars with four canals. Differences between the gold standard and the observations made using the imaging methods were calculated using Spearman's rho correlation coefficient test. The presence of accessory canals in micro-CT images of maxillary and mandibular root canals showed a statistically significant correlation with the stereomicroscopic images used as a gold standard. No statistically significant correlation was found between the CBCT findings and the stereomicroscopic images.Although micro-CT is not suitable for clinical use, it provides more detailed information about minor anatomical structures. However, CBCT is convenient for clinical use but may not be capable of adequately analyzing the internal anatomy of primary teeth.

  9. Comparison of micro-computerized tomography and cone-beam computerized tomography in the detection of accessory canals in primary molars

    International Nuclear Information System (INIS)

    Acar, Buket; Kamburoglu, Kivanc; Tatar, Ilkan; Arikan, Volkan; Celik, Hakan Hamid; Yuksel, Selcen; Ozen, Tuncer

    2015-01-01

    This study was performed to compare the accuracy of micro-computed tomography (CT) and cone-beam computed tomography (CBCT) in detecting accessory canals in primary molars. Forty-one extracted human primary first and second molars were embedded in wax blocks and scanned using micro-CT and CBCT. After the images were taken, the samples were processed using a clearing technique and examined under a stereomicroscope in order to establish the gold standard for this study. The specimens were classified into three groups: maxillary molars, mandibular molars with three canals, and mandibular molars with four canals. Differences between the gold standard and the observations made using the imaging methods were calculated using Spearman's rho correlation coefficient test. The presence of accessory canals in micro-CT images of maxillary and mandibular root canals showed a statistically significant correlation with the stereomicroscopic images used as a gold standard. No statistically significant correlation was found between the CBCT findings and the stereomicroscopic images.Although micro-CT is not suitable for clinical use, it provides more detailed information about minor anatomical structures. However, CBCT is convenient for clinical use but may not be capable of adequately analyzing the internal anatomy of primary teeth

  10. Gamma tomography apparatus

    International Nuclear Information System (INIS)

    Span, F.J.

    1988-01-01

    The patent concerns a gamma tomography apparatus for medical diagnosis. The apparatus comprises a gamma scintillation camera head and a suspension system for supporting and positioning the camera head with respect for the patient. Both total body scanning and single photon emission tomography can be carried out with the apparatus. (U.K.)

  11. Emission computed tomography

    International Nuclear Information System (INIS)

    Budinger, T.F.; Gullberg, G.T.; Huesman, R.H.

    1979-01-01

    This chapter is devoted to the methods of computer assisted tomography for determination of the three-dimensional distribution of gamma-emitting radionuclides in the human body. The major applications of emission computed tomography are in biological research and medical diagnostic procedures. The objectives of these procedures are to make quantitative measurements of in vivo biochemical and hemodynamic functions

  12. Tomography of nonclassical states

    NARCIS (Netherlands)

    Bazrafkan, MR; Man'ko, [No Value

    2003-01-01

    A review of the symplectic tomography method is presented. Superpositions of different types of photon states are considered within the framework of the tomography approach. Such nonclassical photon states as even and odd coherent states, crystallized Schrodinger cat states, and other superposition

  13. Micro-computer based communication system

    International Nuclear Information System (INIS)

    Meyers, M.; Hinton, C.; Pauly, C.; Tau, S.; Rathmell, R.

    1981-01-01

    The CNEA 20UD tandem accelerator manufactured by National Electrostatics Corp. is predominately controlled through a hard wired console. In the past, accelerators have used mechanical control rods to control parameters inside the high voltage terminals and dead sections. The 20UD column, has relatively complex equipment within the terminal and dead sections. Because of its complexity and the length of the column (approximately 48 ft. from ground to terminal) it was concluded that a digital communication link would be required to provide the smooth, high resolution control needed for the ion-optic components and to provide a reliable system to monitor the large number of parameters. To further ensure reliability, some basic components such as foil strippers and the terminal matching quadrupole have back-up control via control rods to allow limited operation in the event of a failure of the digital system

  14. Micro-Computers in Biology Inquiry.

    Science.gov (United States)

    Barnato, Carolyn; Barrett, Kathy

    1981-01-01

    Describes the modification of computer programs (BISON and POLLUT) to accommodate species and areas indigenous to the Pacific Coast area. Suggests that these programs, suitable for PET microcomputers, may foster a long-term, ongoing, inquiry-directed approach in biology. (DS)

  15. Retrograde cystogram for precise localization and irradiation of the urinary bladder of mice

    International Nuclear Information System (INIS)

    Meier, D.

    1988-01-01

    Using a Bangerter cannula contrast medium (Telebrix 30 Meglumine) was instilled for retrograde urography in adult, female mice. Afterwards localization, size and shape of the urinary bladder were examined by computer tomography. (author)

  16. Computerised Axial Tomography (CAT)

    Science.gov (United States)

    1990-06-01

    Ministry of’ Defence, Defence Research Information Centre, UK. Computerised Axial Tomography ( CAT ) Report Secufty C"uMiauion tide Onadtiicadon (U. R, Cor S...DRIC T 8485 COMPUTERISED AXIAL TOMOGRAPHY ( CAT ) F.P. GENTILE, F. SABETTA, V. TRO1* ISS R 78/4.Rome, 1.5 Mlarch 1978 (from Italian) B Distribution(f...dello Radiazioni ISSN 0390--6477 F.P. GENTILE, F. SABETTA. V. TROI Computerised Axial Tomography ( CAT ) March 15, 1978). This paper is a review of

  17. Quantification in emission tomography

    International Nuclear Information System (INIS)

    Buvat, Irene

    2011-11-01

    The objective of this lecture is to understand the possibilities and limitations of the quantitative analysis of single photon emission computed tomography (SPECT) and positron emission tomography (PET) images. It is also to identify the conditions to be fulfilled to obtain reliable quantitative measurements from images. Content: 1 - Introduction: Quantification in emission tomography - definition and challenges; quantification biasing phenomena 2 - Main problems impacting quantification in PET and SPECT: problems, consequences, correction methods, results (Attenuation, scattering, partial volume effect, movement, un-stationary spatial resolution in SPECT, fortuitous coincidences in PET, standardisation in PET); 3 - Synthesis: accessible efficiency, know-how, Precautions, beyond the activity measurement

  18. Positron emission tomography

    International Nuclear Information System (INIS)

    Wienhard, K.; Heiss, W.D.

    1984-01-01

    The principles and selected clinical applications of positron emission tomography are described. In this technique a chemical compound is labeled with a positron emitting isotope and its biochemical pathway is traced by coincidence detection of the two annihilation photons. The application of the techniques of computed tomography allows to reconstruct the spatial distribution of the radioactivity within a subject. The 18 F-deoxyglucose method for quantitative measurement of local glucose metabolism is discussed in order to illustrate the possibilities of positron emission tomography to record physiological processes in vivo. (orig.) [de

  19. Application of three-dimensional computed tomography in craniofacial clinical practice and research.

    Science.gov (United States)

    Anderson, P J; Yong, R; Surman, T L; Rajion, Z A; Ranjitkar, S

    2014-06-01

    Following the invention of the first computed tomography (CT) scanner in the early 1970s, many innovations in three-dimensional (3D) diagnostic imaging technology have occurred, leading to a wide range of applications in craniofacial clinical practice and research. Three-dimensional image analysis provides superior and more detailed information compared with conventional plain two-dimensional (2D) radiography, with the added benefit of 3D printing for preoperative treatment planning and regenerative therapy. Current state-of-the-art multidetector CT (MDCT), also known as medical CT, has an important role in the diagnosis and management of craniofacial injuries and pathology. Three-dimensional cone beam CT (CBCT), pioneered in the 1990s, is gaining increasing popularity in dental and craniofacial clinical practice because of its faster image acquisition at a lower radiation dose, but sound guidelines are needed to ensure its optimal clinical use. Recent innovations in micro-computed tomography (micro-CT) have revolutionized craniofacial biology research by enabling higher resolution scanning of teeth beyond the capabilities of MDCT and CBCT, presenting new prospects for translational clinical research. Even after four decades of refinement, CT technology continues to advance and broaden the horizons of craniofacial clinical practice and phenomics research. © 2014 Australian Dental Association.

  20. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... tomography (CT) scan. View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. ...

  1. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... tomography (CT) scan. View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. ...

  2. Cardiac positron emission tomography

    International Nuclear Information System (INIS)

    Eftekhari, M.; Ejmalian, G.

    2003-01-01

    Positron emission tomography is an intrinsically tool that provide a unique and unparalleled approach for clinicians and researchers to interrogate the heart noninvasively. The ability to label substances of physiological interest with positron-emitting radioisotopes has permitted insight into normal blood flow and metabolism and the alterations that occur with disease states. Positron emission tomography of the heart has evolved as a unique, noninvasive approach for the assessment of myocardial perfusion, metabolism, and function. Because of the intrinsic quantitative nature of positron emission tomography measurements as well as the diverse compounds that can be labeled with positron- emitting radioisotopes, studies with positron emission tomography have provided rich insight into the physiology of the heart under diverse conditions

  3. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... for Brain Tumors Radiation Therapy for Head and Neck Cancer Others American Stroke Association National Stroke Association ... Computer Tomography (CT) Safety During Pregnancy Head and Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine ...

  4. Positron emission tomography

    International Nuclear Information System (INIS)

    Iio, Masahiro

    1982-01-01

    Utilization of positron emission tomography was reviewed in relation to construction and planned construction of small-size medical cyclotrons, planned construction of positron cameras and utilization of short-lived radionuclides. (Chiba, N.)

  5. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... other medical conditions and whether you have a history of heart disease, asthma, diabetes, kidney disease or ... Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to Computed Tomography (CT) - ...

  6. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... other medical conditions and whether you have a history of heart disease, asthma, diabetes, kidney disease or ... Neck Cancer X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to Computed Tomography (CT) - ...

  7. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... top of page Additional Information and Resources RTAnswers.org Radiation Therapy for Brain Tumors Radiation Therapy for ... Tomography (CT) - Head Sponsored by Please note RadiologyInfo.org is not a medical facility. Please contact your ...

  8. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... top of page Additional Information and Resources RTAnswers.org Radiation Therapy for Head and Neck Cancer top ... Tomography (CT) - Sinuses Sponsored by Please note RadiologyInfo.org is not a medical facility. Please contact your ...

  9. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... are the limitations of CT of the Sinuses? What is CT (Computed Tomography) of the Sinuses? Computed ... nasal cavity by small openings. top of page What are some common uses of the procedure? CT ...

  10. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... the limitations of CT Scanning of the Head? What is CT Scanning of the Head? Computed tomography, ... than regular radiographs (x-rays). top of page What are some common uses of the procedure? CT ...

  11. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... of the Head? Computed tomography, more commonly known as a CT or CAT scan, is a diagnostic ... white on the x-ray; soft tissue, such as organs like the heart or liver, shows up ...

  12. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... of the Sinuses? Computed tomography, more commonly known as a CT or CAT scan, is a diagnostic ... white on the x-ray; soft tissue, such as organs like the heart or liver, shows up ...

  13. Intracoronary optical coherence tomography

    DEFF Research Database (Denmark)

    Tenekecioglu, Erhan; Albuquerque, Felipe N; Sotomi, Yohei

    2017-01-01

    By providing valuable information about the coronary artery wall and lumen, intravascular imaging may aid in optimizing interventional procedure results and thereby could improve clinical outcomes following percutaneous coronary intervention (PCI). Intravascular optical coherence tomography (OCT...

  14. Computer tomography in otolaryngology

    International Nuclear Information System (INIS)

    Gradzki, J.

    1981-01-01

    The principles of design and the action of computer tomography which was applied also for the diagnosis of nose, ear and throat diseases are discussed. Computer tomography makes possible visualization of the structures of the nose, nasal sinuses and facial skeleton in transverse and eoronal planes. The method enables an accurate evaluation of the position and size of neoplasms in these regions and differentiation of inflammatory exudates against malignant masses. In otology computer tomography is used particularly in the diagnosis of pontocerebellar angle tumours and otogenic brain abscesses. Computer tomography of the larynx and pharynx provides new diagnostic data owing to the possibility of obtaining transverse sections and visualization of cartilage. Computer tomograms of some cases are presented. (author)

  15. Tomography in nuclear medicine

    International Nuclear Information System (INIS)

    Levi de Cabrejas, Mariana

    1999-01-01

    This book is a contribution to the training and diffusion of the tomography method image diagnosis in nuclear medicine, which principal purpose is the information to professionals and technical personnel, specially for the spanish speaking staff

  16. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info About Us News Physician Resources Professions Site Index A-Z Computed Tomography ( ...

  17. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info About Us News Physician Resources Professions Site Index A-Z Computed Tomography ( ...

  18. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... Computed tomography (CT) of the sinuses uses special x-ray equipment to evaluate the paranasal sinus cavities – hollow, air-filled spaces within the bones of the face surrounding the ...

  19. Electrical Impedance Tomography Technology

    Data.gov (United States)

    National Aeronautics and Space Administration — The goal for the Electrical Impedance Tomography Technology (EITT) project is to develop a reliable portable, lightweight device providing two-dimensional...

  20. Introduction to Seismic Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Rowe, Charlotte Anne [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-11-21

    Tomography is a method of obtaining an image of a 3d object by observing the behavior of energy transmissions through the object. The image is obtained by Interrogating the object with Energy sources at a variety of Locations and observing the Object’s effects on the energy at a Variety of sensors. Tomography was first Used to build 3-dimensional Scans through Human bodies. These Are called computed Tomographic (ct) scans.

  1. Positron emission tomography

    International Nuclear Information System (INIS)

    Dvorak, O.

    1989-01-01

    The principle is briefly described of positron emission tomography, and its benefits and constraints are listed. It is emphasized that positron emission tomography (PET) provides valuable information on metabolic changes in the organism that are otherwise only very difficult to obtain, such as brain diagnosis including relationships between mental disorders and the physiology and pathophysiology of the brain. A PET machine is to be installed in Czechoslovakia in the near future. (L.O.)

  2. Effects of fetal exposure to gamma rays on aggressive behavior in adult male mice

    International Nuclear Information System (INIS)

    Minamisawa, Takeru; Hirokaga, Kouichi; Sasaki, Shunsaku; Noda, Yutaka.

    1992-01-01

    Aggressive behavior (AB) in first generation (F 1 ) hybrid male C57BL/6 x C3H mice irradiated on the 14th day of gestation was studied at 100-135 days of age. Gravid female mice were irradiated with 1.0 or 2.0 Gy of gamma rays to the whole body. The AB of pairs of mice were recorded with a capacitance-induction motility monitor and on videotape. Recordings were continued for 90 min, starting at 2:00 PM. Vigorous wrestling, boxing and biting were regarded as AB. Data recorded at 15-min intervals were stored on micro-computer discs. The body weight for the irradiated group was significantly lower than that for the control group. The number of instances of AB was significantly higher in the irradiated group. The AB of the 2.0 Gy group was significantly more intensive than that of the control group. No difference in the duration of AB was found for the 2 irradiated and the control groups. Results demonstrate that male mice irradiated prenatally show increased aggressiveness. (author)

  3. Cloning Mice.

    Science.gov (United States)

    Ogura, Atsuo

    2017-08-01

    Viable and fertile mice can be generated by somatic nuclear transfer into enucleated oocytes, presumably because the transplanted somatic cell genome becomes reprogrammed by factors in the oocyte. The first somatic cloned offspring of mice were obtained by directly injecting donor nuclei into recipient enucleated oocytes. When this method is used (the so-called Honolulu method of somatic cell nuclear transfer [SCNT]), the donor nuclei readily and completely condense within the enucleated metaphase II-arrested oocytes, which contain high levels of M-phase-promoting factor (MPF). It is believed that the condensation of the donor chromosomes promotes complete reprogramming of the donor genome within the mouse oocytes. Another key to the success of mouse cloning is the use of blunt micropipettes attached to a piezo impact-driving micromanipulation device. This system saves a significant amount of time during the micromanipulation of oocytes and thus minimizes the loss of oocyte viability in vitro. For example, a group of 20 oocytes can be enucleated within 10 min by an experienced operator. This protocol is composed of seven parts: (1) preparing micropipettes, (2) setting up the enucleation and injection micropipettes, (3) collecting and enucleating oocytes, (4) preparing nucleus donor cells, (5) injecting donor nuclei, (6) activating embryos and culturing, and (7) transferring cloned embryos. © 2017 Cold Spring Harbor Laboratory Press.

  4. Tomography studies of biological cells on polymer scaffolds

    International Nuclear Information System (INIS)

    Thurner, P; Mueller, B; Sennhauser, U; Hubbell, J; Mueller, R

    2004-01-01

    Advances in cell biology and tissue engineering rely heavily on performing 2D cell culture experiments. Analysis of these is conventionally done with 2D imaging techniques such as light (LM) or electron microscopy (SEM), since they are readily available. Cells, however, might act significantly differently when cultured in 2D or 3D environments. In order to analyse cells in a 3D arrangement, new imaging techniques are necessary not only in order to visualize the periphery of the cell culture in reflection mode but also to perform qualitative and quantitative investigations of the inner parts. Synchrotron radiation micro-computed tomography (SRμCT) using hard x-rays was shown to be a promising tool that can be used for 3D cell culture visualization. SRμCT allows not only visualization of cell cultures in their native 3D environment but also use of the volumetric nature of this imaging procedure to evaluate the cells quantitatively. In our approach, cells were seeded on polymer yarns, stained and measured with SRμCT in absorption and in differential absorption contrast mode. A new segmentation procedure was developed and the measured volumetric data were quantitatively assessed. Quantification parameters included total cell volume, total yarn volume, cell volume density, which is the ratio of cell to yarn volume, and the radial cell mass distribution. The applied variation of the staining parameter of gold enhancement incubation time was shown to have significant influence on the cell volume density. Differential absorption contrast mode was found to provide similar but no additional information on the investigated sample. Using novel approaches of hierarchical volumetric imaging allows closure of the gap between imaging of whole organs and single cells and might be expanded to even higher resolutions, offering investigation of the cell machinery in closer detail

  5. 4D Electron Tomography

    Science.gov (United States)

    Kwon, Oh-Hoon; Zewail, Ahmed H.

    2010-06-01

    Electron tomography provides three-dimensional (3D) imaging of noncrystalline and crystalline equilibrium structures, as well as elemental volume composition, of materials and biological specimens, including those of viruses and cells. We report the development of 4D electron tomography by integrating the fourth dimension (time resolution) with the 3D spatial resolution obtained from a complete tilt series of 2D projections of an object. The different time frames of tomograms constitute a movie of the object in motion, thus enabling studies of nonequilibrium structures and transient processes. The method was demonstrated using carbon nanotubes of a bracelet-like ring structure for which 4D tomograms display different modes of motion, such as breathing and wiggling, with resonance frequencies up to 30 megahertz. Applications can now make use of the full space-time range with the nanometer-femtosecond resolution of ultrafast electron tomography.

  6. Quantitative cardiac computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Thelen, M.; Dueber, C.; Wolff, P.; Erbel, R.; Hoffmann, T.

    1985-06-01

    The scope and limitations of quantitative cardiac CT have been evaluated in a series of experimental and clinical studies. The left ventricular muscle mass was estimated by computed tomography in 19 dogs (using volumetric methods, measurements in two axes and planes and reference volume). There was good correlation with anatomical findings. The enddiastolic volume of the left ventricle was estimated in 22 patients with cardiomyopathies; using angiography as a reference, CT led to systematic under-estimation. It is also shown that ECG-triggered magnetic resonance tomography results in improved visualisation and may be expected to improve measurements of cardiac morphology.

  7. Optical Coherence Tomography

    DEFF Research Database (Denmark)

    Mogensen, Mette; Themstrup, Lotte; Banzhaf, Christina

    2014-01-01

    Optical coherence tomography (OCT) has developed rapidly since its first realisation in medicine and is currently an emerging technology in the diagnosis of skin disease. OCT is an interferometric technique that detects reflected and backscattered light from tissue and is often described as the o......Optical coherence tomography (OCT) has developed rapidly since its first realisation in medicine and is currently an emerging technology in the diagnosis of skin disease. OCT is an interferometric technique that detects reflected and backscattered light from tissue and is often described...

  8. Digital multilayer tomography

    International Nuclear Information System (INIS)

    Dueber, C.; Klose, K.J.; Thelen, M.

    1991-01-01

    With digital multilayer tomography a sequence of projection images is recorded by an image intensifier television system and stored as digital data during a linear run of a layer sequence. Using this data record, tomograms of the examined body region can be computed for any layer thickness by shifts and superimposition of the single projections later at a digital workstation. The qualities of digital and conventional tomograms are basically comparable. A drawback of digital tomography is its lower local resolution (512 x 512 image matrix), advantages are a lower radiation exposure, a shorter patient examination time, and the facilities of digital image processing (later processing, archive setup, transmission). (orig.) [de

  9. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) is ... a CT scan. View full size with caption Pediatric Content Some imaging tests and treatments have special ...

  10. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) is a fast, painless exam that uses ... of Children's CT? What is Children's CT? Computed tomography, more commonly known as a CT or CAT ...

  11. Computed tomography in facial trauma

    International Nuclear Information System (INIS)

    Zilkha, A.

    1982-01-01

    Computed tomography (CT), plain radiography, and conventional tomography were performed on 30 patients with facial trauma. CT demonstrated bone and soft-tissue involvement. In all cases, CT was superior to tomography in the assessment of facial injury. It is suggested that CT follow plain radiography in the evaluation of facial trauma

  12. Multislice computed tomography coronary angiography

    NARCIS (Netherlands)

    F. Cademartiri (Filippo)

    2005-01-01

    markdownabstract__Abstract__ Computed Tomography (CT) imaging is also known as "CAT scanning" (Computed Axial Tomography). Tomography is from the Greek word "tomos" meaning "slice" or "section" and "graphia" meaning "describing". CT was invented in 1972 by British engineer Godfrey Hounsfield

  13. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Head ...

  14. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Sinuses ...

  15. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... Share your patient story here Images × Image Gallery Patient undergoing computed tomography (CT) scan. View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. Related ...

  16. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... Share your patient story here Images × Image Gallery Patient undergoing computed tomography (CT) scan. View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. Related ...

  17. Computed tomography in traumatology

    International Nuclear Information System (INIS)

    Heller, M.; Jend, H.H.

    1986-01-01

    This volume offers a critical review and assessment of new avenues opened up by computed tomography in traumatology. Over 200 illustrations, including numerous CT scans, aid the physician engaged emergency care and postoperative treatment of accident victims. Technical prerequisites, special techniques of investigation, pathomorphology of organ changes conditioned by trauma, diagnostic leading symptoms and signs, and diagnostics of iatrogenic injuries and lesions are presented

  18. Computed tomography system

    International Nuclear Information System (INIS)

    Lambert, T.W.; Blake, J.E.

    1981-01-01

    This invention relates to computed tomography and is particularly concerned with determining the CT numbers of zones of interest in an image displayed on a cathode ray tube which zones lie in the so-called level or center of the gray scale window. (author)

  19. Holography and tomography

    Energy Technology Data Exchange (ETDEWEB)

    Howells, M. [Lawrence Berkeley National Lab., CA (United States)

    1997-02-01

    This session includes a collection of outlines of pertinent information, diagrams, graphs, electron micrographs, and color photographs pertaining to historical aspects and recent advances in the development of X-ray Gabor Holography. Many of the photographs feature or pertain to instrumentation used in holography, tomography, and cryo-holography.

  20. Celebral computerized tomography

    International Nuclear Information System (INIS)

    Lofteroed, B.; Sortland, O.

    1985-01-01

    Indications for cerebral computerized tomography (CT) and the diagnostic results from this examination are evaluated in 127 children. Pathological changes were found in 31 children, mostly based on such indications as increasing head size, suspicion of brain tumor, cerebral paresis, delayed psychomotor development and epileptic seizures. A list of indications for CT in children is given

  1. Positron emission tomography

    International Nuclear Information System (INIS)

    Pavuk, M.

    2003-12-01

    The aim of this project is to provide a simple summary of new trends in positron emission tomography and its basic physical principles. It provides thereby compendious introduction of the trends of the present development in diagnostics using PET systems. A review of available literature was performed. (author)

  2. Chest computed tomography

    DEFF Research Database (Denmark)

    Loeve, Martine; Krestin, Gabriel P.; Rosenfeld, Margaret

    2013-01-01

    are not suitable to study CF lung disease in young children. Chest computed tomography (CT) holds great promise for use as a sensitive surrogate endpoint in CF. A large body of evidence has been produced to validate the use of chest CT as primary endpoint to study CF lung disease. However, before chest CT can...

  3. Positron emission tomography

    NARCIS (Netherlands)

    Paans, AMJ

    Positron Emission Tomography (PET) is a method for determining biochemical and physiological processes in vivo in a quantitative way by using radiopharmaceuticals labelled with positron emitting radionuclides as C-11, N-13, O-15 and F-18 and by measuring the annihilation radiation using a

  4. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... Computed tomography (CT) of the head uses special x-ray equipment to help assess head injuries, severe headaches, ... is a diagnostic medical test that, like traditional x-rays, produces multiple images or pictures of the inside ...

  5. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... Computed tomography (CT) of the sinuses uses special x-ray equipment to evaluate the paranasal sinus cavities – hollow, ... is a diagnostic medical test that, like traditional x-rays, produces multiple images or pictures of the inside ...

  6. Computed tomography for radiographers

    International Nuclear Information System (INIS)

    Brooker, M.J.

    1986-01-01

    This book is directed towards giving radiographers an introduction to and basic knowledge of computerized tomography. The technical section discusses gantries and x-ray production, computer and disc drive image display, storage, artefacts quality assurance and design of departments. The clinical section includes patient preparation, radiotherapy planning, and interpretation of images from various areas of the anatomy. (U.K.)

  7. Holography and tomography

    International Nuclear Information System (INIS)

    Howells, M.

    1997-01-01

    This session includes a collection of outlines of pertinent information, diagrams, graphs, electron micrographs, and color photographs pertaining to historical aspects and recent advances in the development of X-ray Gabor Holography. Many of the photographs feature or pertain to instrumentation used in holography, tomography, and cryo-holography

  8. Role of paraoxonase-1 in bone anabolic effects of parathyroid hormone in hyperlipidemic mice

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Jinxiu [Department of Physiology, University of California, Los Angeles (United States); Cheng, Henry [Department of Medicine, University of California, Los Angeles (United States); Atti, Elisa [Division of Diagnostic and Surgical Sciences, School of Dentistry, University of California, Los Angeles (United States); Shih, Diana M. [Department of Medicine, University of California, Los Angeles (United States); Demer, Linda L. [Department of Physiology, University of California, Los Angeles (United States); Department of Medicine, University of California, Los Angeles (United States); Department of Bioengineering, University of California, Los Angeles (United States); Tintut, Yin, E-mail: ytintut@mednet.ucla.edu [Department of Medicine, University of California, Los Angeles (United States)

    2013-02-01

    Highlights: ► Anabolic effects of PTH were tested in hyperlipidemic mice overexpressing PON1. ► Expression of antioxidant regulatory genes was induced in PON1 overexpression. ► Bone resorptive activity was reduced in PON1 overexpressing hyperlipidemic mice. ► PON1 restored responsiveness to intermittent PTH in bones of hyperlipidemic mice. -- Abstract: Hyperlipidemia blunts anabolic effects of intermittent parathyroid hormone (PTH) on cortical bone, and the responsiveness to PTH are restored in part by oral administration of the antioxidant ApoA-I mimetic peptide, D-4F. To evaluate the mechanism of this rescue, hyperlipidemic mice overexpressing the high-density lipoprotein-associated antioxidant enzyme, paraoxonase 1 (Ldlr{sup −/−}PON1{sup tg}) were generated, and daily PTH injections were administered to Ldlr{sup −/−}PON1{sup tg} and to littermate Ldlr{sup −/−} mice. Expression of bone regulatory genes was determined by realtime RT-qPCR, and cortical bone parameters of the femoral bones by micro-computed tomographic analyses. PTH-treated Ldlr{sup −/−}PON1{sup tg} mice had significantly greater expression of PTH receptor (PTH1R), activating transcription factor-4 (ATF4), and osteoprotegerin (OPG) in femoral cortical bone, as well as significantly greater cortical bone mineral content, thickness, and area in femoral diaphyses compared with untreated Ldlr{sup −/−}PON1{sup tg} mice. In contrast, in control mice (Ldlr{sup −/−}) without PON1 overexpression, PTH treatment did not induce these markers. Calvarial bone of PTH-treated Ldlr{sup −/−}PON1{sup tg} mice also had significantly greater expression of osteoblastic differentiation marker genes as well as BMP-2-target and Wnt-target genes. Untreated Ldlr{sup −/−}PON1{sup tg} mice had significantly greater expression of PTHR1 than untreated Ldlr{sup −/−} mice, whereas sclerostin expression was reduced. In femoral cortical bones, expression levels of transcription factors, Fox

  9. Targeted microbubbles for imaging tumor angiogenesis: assessment of whole-body biodistribution with dynamic micro-PET in mice

    DEFF Research Database (Denmark)

    Willmann, Jürgen K; Cheng, Zhen; Davis, Corrine

    2008-01-01

    To evaluate in vivo whole-body biodistribution of microbubbles (MBs) targeted to tumor angiogenesis-related vascular endothelial growth factor (VEGF) receptor 2 (VEGFR2) by using dynamic micro-positron emission tomography (PET) in living mice.......To evaluate in vivo whole-body biodistribution of microbubbles (MBs) targeted to tumor angiogenesis-related vascular endothelial growth factor (VEGF) receptor 2 (VEGFR2) by using dynamic micro-positron emission tomography (PET) in living mice....

  10. Minimal invasive localization of the germinal disc in ovo for subsequent chicken sexing using optical coherence tomography

    Science.gov (United States)

    Burkhardt, Anke; Geissler, Stefan; Cimalla, Peter; Walther, Julia; Koch, Edmund

    2010-02-01

    Reason for using optical coherence tomography (OCT) to locate the germinal disc is the questionable and ethically alarming killing of male layer chickens because for the layer line only the females are necessary. To avoid this and to protect the animal rights, the sex of the fertilized chicken egg has to be determined as early as possible in the unincubated state. Because the information whether the chick becomes male or female can be found in the germinal disc an accurate localization for sexing is essential. The germinal disc is located somewhere on top of the yolk and has a diameter of approximately 4 - 5 mm. Different imaging methods like ultrasonography, 3D-X-ray micro computed tomography and magnetic resonance imaging were used for localization until now, but found to be impractical. The goal of this study is to prove if OCT can be a moderate approach for the precise in ovo localization. Because the eggshell is an impenetrable barrier for OCT and to minimize the penetration of germs a very small hole is placed in the eggshell and a fan-shaped optical scanning pattern is used.

  11. Highly resolving computerized tomography

    International Nuclear Information System (INIS)

    Kurtz, B.; Petersen, D.; Walter, E.

    1984-01-01

    With the development of highly-resolving devices for computerized tomography, CT diagnosis of the lumbar vertebral column has gained increasing importance. As an ambulatory, non-invasive method it has proved in comparative studies to be at least equivalent to myelography in the detection of dislocations of inter-vertebral disks (4,6,7,15). Because with modern devices not alone the bones, but especially the spinal soft part structures are clearly and precisely presented with a resolution of distinctly below 1 mm, a further improvement of the results is expected as experience will increase. The authors report on the diagnosis of the lumbar vertebral column with the aid of a modern device for computerized tomography and wish to draw particular attention to the possibility of doing this investigation as a routine, and to the diagnostic value of secondary reconstructions. (BWU) [de

  12. Highly resolving computerized tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, B.; Petersen, D.; Walter, E.

    1984-01-01

    With the development of highly-resolving devices for computerized tomography, CT diagnosis of the lumbar vertebral column has gained increasing importance. As an ambulatory, non-invasive method it has proved in comparative studies to be at least equivalent to myelography in the detection of dislocations of inter-vertebral disks (4,6,7,15). Because with modern devices not alone the bones, but especially the spinal soft part structures are clearly and precisely presented with a resolution of distinctly below 1 mm, a further improvement of the results is expected as experience will increase. The authors report on the diagnosis of the lumbar vertebral column with the aid of a modern device for computerized tomography and wish to draw particular attention to the possibility of doing this investigation as a routine, and to the diagnostic value of secondary reconstructions.

  13. Mathematical Methods in Tomography

    CERN Document Server

    Louis, Alfred; Natterer, Frank

    1991-01-01

    The conference was devoted to the discussion of present and future techniques in medical imaging, including 3D x-ray CT, ultrasound and diffraction tomography, and biomagnetic ima- ging. The mathematical models, their theoretical aspects and the development of algorithms were treated. The proceedings contains surveys on reconstruction in inverse obstacle scat- tering, inversion in 3D, and constrained least squares pro- blems.Research papers include besides the mentioned imaging techniques presentations on image reconstruction in Hilbert spaces, singular value decompositions, 3D cone beam recon- struction, diffuse tomography, regularization of ill-posed problems, evaluation reconstruction algorithms and applica- tions in non-medical fields. Contents: Theoretical Aspects: J.Boman: Helgason' s support theorem for Radon transforms-a newproof and a generalization -P.Maass: Singular value de- compositions for Radon transforms- W.R.Madych: Image recon- struction in Hilbert space -R.G.Mukhometov: A problem of in- teg...

  14. Neutron beam tomography software

    International Nuclear Information System (INIS)

    Newbery, A.C.R.

    1988-05-01

    When a sample is traversed by a neutron beam, inhomogeneities in the sample will cause deflections, and the deflections will permit conclusions to be drawn concerning the location and size of the inhomogeneities. The associated computation is similar to problems in tomography, analogous to X-ray tomography though significantly different in detail. We do not have any point-sample information, but only mean values over short line segments. Since each mean value is derived from a separate neutron counter, the quantity of available data has to be modest; also, since each datum is an integral, its geometric precision is inferior to that of X-ray data. Our software is designed to cope with these difficulties. (orig.) [de

  15. Positron emission tomography

    International Nuclear Information System (INIS)

    Yamamoto, Y.L.; Thompson, C.J.; Diksic, M.; Meyer, E.; Feindel, W.H.

    1984-01-01

    One of the most exciting new technologies introduced in the last 10 yr is positron emission tomography (PET). PET provides quantitative, three-dimensional images for the study of specific biochemical and physiological processes in the human body. This approach is analogous to quantitative in-vivo autoradiography but has the added advantage of permitting non-invasive in vivo studies. PET scanning requires a small cyclotron to produce short-lived positron emitting isotopes such as oxygen-15, carbon-11, nitrogen-13 and fluorine-18. Proper radiochemical facilities and advanced computer equipment are also needed. Most important, PET requires a multidisciplinary scientific team of physicists, radiochemists, mathematicians, biochemists and physicians. The most recent trends are reviewed in the imaging technology, radiochemistry, methodology and clinical applications of positron emission tomography. (author)

  16. Reinforced concrete tomography

    International Nuclear Information System (INIS)

    Mariscotti, M.A.J.; Morixe, M.; Tarela, P.A.; Thieberger, P.

    1997-01-01

    In this paper we describe the technique of reinforced concrete tomography, its historical background, recent technological developments and main applications. Gamma radiation sensitive plates are imprinted with radiation going through the concrete sample under study, and then processed to reveal the presence of reinforcement and defects in the material density. The three dimensional reconstruction, or tomography, of the reinforcement out of a single gammagraphy is an original development alternative to conventional methods. Re-bar diameters and positions may be determined with an accuracy of ± 1 mm 0.5-1 cm, respectively. The non-destructive character of this technique makes it particularly attractive in cases of inhabited buildings and diagnoses of balconies. (author) [es

  17. Optical Tomography in Combustion

    DEFF Research Database (Denmark)

    Evseev, Vadim

    spectral measurements at several line-of-sights with a view to applications for tomographic measurements on full-scale industrial combustion systems. The system was successfully applied on industrial scale for simultaneous fast exhaust gas temperature measurements in the three optical ports of the exhaust......D project, it was also important to investigate the spectral properties of major combustion species such as carbon dioxide and carbon monoxide in the infrared range at high temperatures to provide the theoretical background for the development of the optical tomography methods. The new software....... JQSRT 113 (2012) 2222, 10.1016/j.jqsrt.2012.07.015] included in the PhD thesis as an attachment. The knowledge and experience gained in the PhD project is the first important step towards introducing the advanced optical tomography methods of combustion diagnostics developed in the project to future...

  18. Computed Tomography. Chapter 11

    Energy Technology Data Exchange (ETDEWEB)

    Geleijns, J. [Leiden University Medical Centre, Leiden (Netherlands)

    2014-09-15

    After its clinical introduction in 1971, computed tomography (CT) developed from an X ray modality that was limited to axial imaging of the brain in neuroradiology into a versatile 3-D whole body imaging modality for a wide range of applications, including oncology, vascular radiology, cardiology, traumatology and interventional radiology. CT is applied for diagnosis and follow-up studies of patients, for planning of radiotherapy, and even for screening of healthy subpopulations with specific risk factors.

  19. Positron emission tomography

    International Nuclear Information System (INIS)

    Chandrasekhar, Preethi; Himabindu, Pucha

    2000-01-01

    Positron Emission Tomography (PET) is a non-invasive nuclear imaging technique used to study different molecular pathways and anatomical structures. PET has found extensive applications in various fields of medicine viz. cardiology, oncology, psychiatry/psychology, neuro science and pulmonology. This study paper basically deals with the physics, chemistry and biology behind the PET technique. It discusses the methodology for generation of the radiotracers responsible for emission of positrons and the annihilation and detection techniques. (author)

  20. Compton tomography system

    Science.gov (United States)

    Grubsky, Victor; Romanoov, Volodymyr; Shoemaker, Keith; Patton, Edward Matthew; Jannson, Tomasz

    2016-02-02

    A Compton tomography system comprises an x-ray source configured to produce a planar x-ray beam. The beam irradiates a slice of an object to be imaged, producing Compton-scattered x-rays. The Compton-scattered x-rays are imaged by an x-ray camera. Translation of the object with respect to the source and camera or vice versa allows three-dimensional object imaging.

  1. High resolution positron tomography

    International Nuclear Information System (INIS)

    Brownell, G.L.; Burnham, C.A.

    1982-01-01

    The limits of spatial resolution in practical positron tomography are examined. The four factors that limit spatial resolution are: positron range; small angle deviation; detector dimensions and properties; statistics. Of these factors, positron range may be considered the fundamental physical limitation since it is independent of instrument properties. The other factors are to a greater or lesser extent dependent on the design of the tomograph

  2. Positron emission tomography

    International Nuclear Information System (INIS)

    Marchenkov, N.S.

    2000-01-01

    The foundations of the positron emission tomography (PET), widely used for the medical diagnostics, are considered. The brief description of the cyclotron for production of radionuclides, applied in the PET, the target devices for manufacturing the position emitters, the moduli for the radiopharmaceuticals synthesis (RPS) for the PET is presented. The necessity and concept of complete automation of the RPS for the PET are discussed [ru

  3. Computed Tomography Status

    Science.gov (United States)

    Hansche, B. D.

    1983-01-01

    Computed tomography (CT) is a relatively new radiographic technique which has become widely used in the medical field, where it is better known as computerized axial tomographic (CAT) scanning. This technique is also being adopted by the industrial radiographic community, although the greater range of densities, variation in samples sizes, plus possible requirement for finer resolution make it difficult to duplicate the excellent results that the medical scanners have achieved.

  4. Coded aperture tomography revisited

    International Nuclear Information System (INIS)

    Bizais, Y.; Rowe, R.W.; Zubal, I.G.; Bennett, G.W.; Brill, A.B.

    1983-01-01

    Coded aperture (CA) Tomography never achieved wide spread use in Nuclear Medicine, except for the degenerate case of Seven Pinhole tomagraphy (7PHT). However it enjoys several attractive features (high sensitivity and tomographic ability with a statis detector). On the other hand, resolution is usually poor especially along the depth axis and the reconstructed volume is rather limited. Arguments are presented justifying the position that CA tomography can be useful for imaging time-varying 3D structures, if its major drawbacks (poor longitudinal resolution and difficulty in quantification) are overcome. Poor results obtained with 7PHT can be explained by both a very limited angular range sampled and a crude modelling of the image formation process. Therefore improvements can be expected by the use of a dual-detector system, along with a better understanding of its sampling properties and the use of more powerful reconstruction algorithms. Non overlapping multipinhole plates, because they do not involve a decoding procedure, should be considered first for practical applications. Use of real CA should be considered for cases in which non overlapping multipinhole plates do not lead to satisfactory solutions. We have been and currently are carrying out theoretical and experimental works, in order to define the factors which limit CA imaging and to propose satisfactory solutions for Dynamic Emission Tomography

  5. Cardiac positron tomography

    International Nuclear Information System (INIS)

    Geltmann, E.M.; Roberts, R.; Sobel, B.E.

    1980-01-01

    Positron emission tomography (PET) performed after the administration of the positron-emitting radionuclides carbon-11 ( 11 C), nitrogen-13 ( 13 N), oxygen-15 ( 15 O) and fluorine-18 ( 18 F) has permitted the improved noninvasive assessment of the regional myocardial metabolism of normal physiologic substrates and intermediates and their cogeners. In experimental animals, the rate of oxidation of 11 C-palmitate correlates closely with other indexes of oxygen consumption, and the extraction of 11 C-palmitate (like that of 18 F-fatty acids and 18 F-fluoredoxyglucose) ist markedly diminished in regions of myocardial ischemia. In both experimental animals and in patients, myocardial infarct site and size, determined by positron emission tomography after the intravenous injection of 11 C-palmitate, correlate closely with the electrocardiographic infarct locus and enzymatically estimated infarct size as well as with the location and extent of regional left ventricular wall motion abnormalities. PET offers promise for assessment of flow as well despite the complexities involved. PET with 13 NH 3 appears to provide one useful qualitative index, although this tracer ist actively metabolized. Because of the quantitative capabilities of positron emission tomography and the rapid progress which is being made in the development of fast scan, multi-slice, and gated instrumentation, this technique is likely to facilitate improved understanding and characterization of regional myocardial metabolism and blood flow in man under physiological and pathophysiological conditions. (orig.) [de

  6. Mathematics of Computed Tomography

    Science.gov (United States)

    Hawkins, William Grant

    A review of the applications of the Radon transform is presented, with emphasis on emission computed tomography and transmission computed tomography. The theory of the 2D and 3D Radon transforms, and the effects of attenuation for emission computed tomography are presented. The algebraic iterative methods, their importance and limitations are reviewed. Analytic solutions of the 2D problem the convolution and frequency filtering methods based on linear shift invariant theory, and the solution of the circular harmonic decomposition by integral transform theory--are reviewed. The relation between the invisible kernels, the inverse circular harmonic transform, and the consistency conditions are demonstrated. The discussion and review are extended to the 3D problem-convolution, frequency filtering, spherical harmonic transform solutions, and consistency conditions. The Cormack algorithm based on reconstruction with Zernike polynomials is reviewed. An analogous algorithm and set of reconstruction polynomials is developed for the spherical harmonic transform. The relations between the consistency conditions, boundary conditions and orthogonal basis functions for the 2D projection harmonics are delineated and extended to the 3D case. The equivalence of the inverse circular harmonic transform, the inverse Radon transform, and the inverse Cormack transform is presented. The use of the number of nodes of a projection harmonic as a filter is discussed. Numerical methods for the efficient implementation of angular harmonic algorithms based on orthogonal functions and stable recursion are presented. The derivation of a lower bound for the signal-to-noise ratio of the Cormack algorithm is derived.

  7. Six dimensional X-ray Tensor Tomography with a compact laboratory setup

    Science.gov (United States)

    Sharma, Y.; Wieczorek, M.; Schaff, F.; Seyyedi, S.; Prade, F.; Pfeiffer, F.; Lasser, T.

    2016-09-01

    Attenuation based X-ray micro computed tomography (XCT) provides three-dimensional images with micrometer resolution. However, there is a trade-off between the smallest size of the structures that can be resolved and the measurable sample size. In this letter, we present an imaging method using a compact laboratory setup that reveals information about micrometer-sized structures within samples that are several orders of magnitudes larger. We combine the anisotropic dark-field signal obtained in a grating interferometer and advanced tomographic reconstruction methods to reconstruct a six dimensional scattering tensor at every spatial location in three dimensions. The scattering tensor, thus obtained, encodes information about the orientation of micron-sized structures such as fibres in composite materials or dentinal tubules in human teeth. The sparse acquisition schemes presented in this letter enable the measurement of the full scattering tensor at every spatial location and can be easily incorporated in a practical, commercially feasible laboratory setup using conventional X-ray tubes, thus allowing for widespread industrial applications.

  8. In Vivo Diffuse Optical Tomography and Fluorescence Molecular Tomography

    Directory of Open Access Journals (Sweden)

    Mingze Li

    2010-01-01

    Full Text Available Diffuse optical tomography (DOT and fluorescence molecular tomography (FMT are two attractive imaging techniques for in vivo physiological and psychological research. They have distinct advantages such as non-invasiveness, non-ionizing radiation, high sensitivity and longitudinal monitoring. This paper reviews the key components of DOT and FMT. Light propagation model, mathematical reconstruction algorithm, imaging instrumentation and medical applications are included. Future challenges and perspective on optical tomography are discussed.

  9. Mesenteric panniculitis: computed tomography aspects

    International Nuclear Information System (INIS)

    Moreira, Luiza Beatriz Melo; Alves, Jose Ricardo Duarte; Marchiori, Edson; Pinheiro, Ricardo Andrade; Melo, Alessandro Severo Alves de; Noro, Fabio

    2001-01-01

    Mesenteric panniculitis is an inflammatory process that represents the second stage of a rare progressive disease involving the adipose tissue of the mesentery. Imaging methods used in the diagnosis of mesenteric panniculitis include barium studies, ultrasonography, computed tomography and magnetic resonance imaging. Computed tomography is important for both, diagnosis and evaluation of the extension of the disease and treatment monitoring. Computed tomography findings may vary according to the stage of the disease and the amount of inflammatory material or fibrosis. There is also good correlation between the computed tomography and anatomical pathology findings. The authors studied 10 patients with mesenteric panniculitis submitted to computed tomography. Magnetic resonance imaging was also performed in one patient. In all patients, computed tomography revealed a heterogeneous mass in the mesentery with density of fat, interspersed with areas of soft tissue density and dilated vessels. (author)

  10. Scanning Microwave Induced Acoustic Tomography

    National Research Council Canada - National Science Library

    Wang, Lihong V

    2002-01-01

    .... Specifically, our accomplishments include (1) an exact and an approximate time-domain reconstruction algorithm for thermoacoustic tomography in a spherical geometry was derived and published, (2...

  11. Ambient occlusion - A powerful algorithm to segment shell and skeletal intrapores in computed tomography data

    Science.gov (United States)

    Titschack, J.; Baum, D.; Matsuyama, K.; Boos, K.; Färber, C.; Kahl, W.-A.; Ehrig, K.; Meinel, D.; Soriano, C.; Stock, S. R.

    2018-06-01

    During the last decades, X-ray (micro-)computed tomography has gained increasing attention for the description of porous skeletal and shell structures of various organism groups. However, their quantitative analysis is often hampered by the difficulty to discriminate cavities and pores within the object from the surrounding region. Herein, we test the ambient occlusion (AO) algorithm and newly implemented optimisations for the segmentation of cavities (implemented in the software Amira). The segmentation accuracy is evaluated as a function of (i) changes in the ray length input variable, and (ii) the usage of AO (scalar) field and other AO-derived (scalar) fields. The results clearly indicate that the AO field itself outperforms all other AO-derived fields in terms of segmentation accuracy and robustness against variations in the ray length input variable. The newly implemented optimisations improved the AO field-based segmentation only slightly, while the segmentations based on the AO-derived fields improved considerably. Additionally, we evaluated the potential of the AO field and AO-derived fields for the separation and classification of cavities as well as skeletal structures by comparing them with commonly used distance-map-based segmentations. For this, we tested the zooid separation within a bryozoan colony, the stereom classification of an ophiuroid tooth, the separation of bioerosion traces within a marble block and the calice (central cavity)-pore separation within a dendrophyllid coral. The obtained results clearly indicate that the ideal input field depends on the three-dimensional morphology of the object of interest. The segmentations based on the AO-derived fields often provided cavity separations and skeleton classifications that were superior to or impossible to obtain with commonly used distance-map-based segmentations. The combined usage of various AO-derived fields by supervised or unsupervised segmentation algorithms might provide a promising

  12. Positron Emission Tomography (PET)

    International Nuclear Information System (INIS)

    Welch, M.J.

    1990-01-01

    Positron emission tomography (PET) assesses biochemical processes in the living subject, producing images of function rather than form. Using PET, physicians are able to obtain not the anatomical information provided by other medical imaging techniques, but pictures of physiological activity. In metaphoric terms, traditional imaging methods supply a map of the body's roadways, its, anatomy; PET shows the traffic along those paths, its biochemistry. This document discusses the principles of PET, the radiopharmaceuticals in PET, PET research, clinical applications of PET, the cost of PET, training of individuals for PET, the role of the United States Department of Energy in PET, and the futures of PET. 22 figs

  13. Computed tomography device

    International Nuclear Information System (INIS)

    Ohhashi, A.

    1985-01-01

    A computed tomography device comprising a subtraction unit which obtains differential data strings representing the difference between each time-serial projection data string of a group of projection data strings corresponding to a prospective reconstruction image generated by projection data strings acquired by a data acquisition system, a convolution unit which convolves each time-serial projection data string of the group of projection data strings corresponding to the prospective reconstruction image, and a back-projection unit which back-projects the convolved data strings

  14. Compressive Phase Contrast Tomography

    International Nuclear Information System (INIS)

    Maia, Filipe; MacDowell, Alastair; Marchesini, Stefano; Padmore, Howard A.; Parkinson, Dula Y.; Pien, Jack; Schirotzek, Andre; Yang, Chao

    2010-01-01

    When x-rays penetrate soft matter, their phase changes more rapidly than their amplitude. Interference effects visible with high brightness sources creates higher contrast, edge enhanced images. When the object is piecewise smooth (made of big blocks of a few components), such higher contrast datasets have a sparse solution. We apply basis pursuit solvers to improve SNR, remove ring artifacts, reduce the number of views and radiation dose from phase contrast datasets collected at the Hard X-Ray Micro Tomography Beamline at the Advanced Light Source. We report a GPU code for the most computationally intensive task, the gridding and inverse gridding algorithm (non uniform sampled Fourier transform).

  15. Positron Emission Tomography (PET)

    Energy Technology Data Exchange (ETDEWEB)

    Welch, M.J.

    1990-01-01

    Positron emission tomography (PET) assesses biochemical processes in the living subject, producing images of function rather than form. Using PET, physicians are able to obtain not the anatomical information provided by other medical imaging techniques, but pictures of physiological activity. In metaphoric terms, traditional imaging methods supply a map of the body's roadways, its, anatomy; PET shows the traffic along those paths, its biochemistry. This document discusses the principles of PET, the radiopharmaceuticals in PET, PET research, clinical applications of PET, the cost of PET, training of individuals for PET, the role of the United States Department of Energy in PET, and the futures of PET. 22 figs.

  16. Recent RI tomography

    International Nuclear Information System (INIS)

    Katsuyama, Naofumi; Kawakami, Kenshi

    1979-01-01

    In this paper, new equipments for radionuclide tomography and recent radiopharmaceuticals with positron emission are described. Positron CT is very usefull for functional imaging. Those nucleides 11 C, 13 N and 15 O have been studied for their sake, but used as a usefull tool as tracer elements for the basic research in the fields of chemistry, bio-chemistry, biology and medicine. Also they have been utilized in the diagnosis of diseases, particularly in the non-invasive and dynamic assessment of metabolic and functional disorders in the patients. We will also describe the clinical usefullness of a commercial scanner such as the Anger multiplane tomographic scanner (PHO/CON). (author)

  17. Gantry for computed tomography

    International Nuclear Information System (INIS)

    Kelman, A.L.; Peterson, T.E.

    1981-01-01

    A novel design of gantry for use in computed tomography is described in detail. In the new gantry, curved tracks are mounted to the laterally spaced apart sides of the frame which rotates and carries the detector and X-ray source. This permits the frame to be tilted either side of vertical enabling angular slices of body layers to be viewed and allows simplification of the algorithm which the computer uses for image reconstruction. The tracks are supported on rollers which carry the substantial weight. Explicit engineering details are presented especially of the ball bearing races used in the rotation. (U.K.)

  18. Gantry for computed tomography

    International Nuclear Information System (INIS)

    Brandt, R.T.; Hein, P.W.

    1981-01-01

    A novel design of gantry for use in computed tomography is described in detail. In the new gantry, curved tracks are mounted to the laterally spaced apart sides of the frame which rotates and carries the detector and X-ray source. This permits the frame to be tilted either side of vertical enabling angular slices of body layers to be viewed and allows simplification of the algorithm which the computer uses for image reconstruction. The tracks are supported on rollers which carry the substantial weight. Explicit engineering details are presented. (U.K.)

  19. Method for computed tomography

    International Nuclear Information System (INIS)

    Wagner, W.

    1980-01-01

    In transversal computer tomography apparatus, in which the positioning zone in which the patient can be positioned is larger than the scanning zone in which a body slice can be scanned, reconstruction errors are liable to occur. These errors are caused by incomplete irradiation of the body during examination. They become manifest not only as an incorrect image of the area not irradiated, but also have an adverse effect on the image of the other, completely irradiated areas. The invention enables reduction of these errors

  20. Positron Emission Tomography (PET)

    Science.gov (United States)

    Welch, M. J.

    1990-01-01

    Positron emission tomography (PET) assesses biochemical processes in the living subject, producing images of function rather than form. Using PET, physicians are able to obtain not the anatomical information provided by other medical imaging techniques, but pictures of physiological activity. In metaphoric terms, traditional imaging methods supply a map of the body's roadways, its, anatomy; PET shows the traffic along those paths, its biochemistry. This document discusses the principles of PET, the radiopharmaceuticals in PET, PET research, clinical applications of PET, the cost of PET, training of individuals for PET, the role of the United States Department of Energy in PET, and the futures of PET.

  1. Solar Stereoscopy and Tomography

    Directory of Open Access Journals (Sweden)

    Markus J. Aschwanden

    2011-10-01

    Full Text Available We review stereoscopic and tomographic methods used in the solar corona, including ground-based and space-based measurements, using solar rotation or multiple spacecraft vantage points, in particular from the STEREO mission during 2007--2010. Stereoscopic and tomographic observations in the solar corona include large-scale structures, streamers, active regions, coronal loops, loop oscillations, acoustic waves in loops, erupting filaments and prominences, bright points, jets, plumes, flares, CME source regions, and CME-triggered global coronal waves. Applications in the solar interior (helioseismic tomography and reconstruction and tracking of CMEs from the outer corona and into the heliosphere (interplanetary CMEs are not included.

  2. Radial reflection diffraction tomography

    Science.gov (United States)

    Lehman, Sean K.

    2012-12-18

    A wave-based tomographic imaging method and apparatus based upon one or more rotating radially outward oriented transmitting and receiving elements have been developed for non-destructive evaluation. At successive angular locations at a fixed radius, a predetermined transmitting element can launch a primary field and one or more predetermined receiving elements can collect the backscattered field in a "pitch/catch" operation. A Hilbert space inverse wave (HSIW) algorithm can construct images of the received scattered energy waves using operating modes chosen for a particular application. Applications include, improved intravascular imaging, bore hole tomography, and non-destructive evaluation (NDE) of parts having existing access holes.

  3. Positron emission tomography

    CERN Document Server

    Paans, A M J

    2006-01-01

    Positron Emission Tomography (PET) is a method for measuring biochemical and physiological processes in vivo in a quantitative way by using radiopharmaceuticals labelled with positron emitting radionuclides such as 11C, 13N, 15O and 18F and by measuring the annihilation radiation using a coincidence technique. This includes also the measurement of the pharmacokinetics of labelled drugs and the measurement of the effects of drugs on metabolism. Also deviations of normal metabolism can be measured and insight into biological processes responsible for diseases can be obtained. At present the combined PET/CT scanner is the most frequently used scanner for whole-body scanning in the field of oncology.

  4. Positron emission tomography

    International Nuclear Information System (INIS)

    Paans, A.M.J.

    1981-01-01

    Positron emitting radiopharmaceuticals have special applications in in-vivo studies of biochemical processes. The combination of a cyclotron for the production of radionuclides and a positron emission tomograph for the registration of the distribution of radioactivity in the body enables the measurement of local radioactivity concentration in tissues, and opens up new possibilities in the diagnosis and examination of abnormalities in the metabolism. The principles and procedures of positron emission tomography are described and the necessary apparatus considered, with emphasis on the positron camera. The first clinical applications using 55 Co bloemycine for tumor detection are presented. (C.F.)

  5. Dynamic tomography in dentistry

    International Nuclear Information System (INIS)

    Richards, A.G.

    1976-01-01

    Dynamic tomography is a procedure in which a sandwich of eight underexposed radiographs is utilized to display sharp images of details lying in a thin layer at any chosen depth within a subject. When the sandwich of films is viewed by transmitted light, the location of this chosen layer can be moved up or down within the subject by simply mechanically moving the radiographs in a precise manner relative to each other. The amount of radiation used in exposing the eight radiographs is the same as would be used to fully expose two normal radiographs

  6. Dosimetry in computed tomography

    International Nuclear Information System (INIS)

    Andisco, D.; Blanco, S.; Buzzia, A.E.

    2014-01-01

    Objective: The amount of computed tomography (CT) studies that are performed each year in the world is growing exponentially mainly due to the incorporation of multislice CT that allows studies in a few seconds. But, despite the benefit received by patients with the diagnosis, radiation dose is a concern in the professional community and it has be reduced as much as reasonably possible. This article describes the main dosimetric CT units used in order to work with this practice easily, using the values that provide modern equipment and internationally known reference levels. (authors) [es

  7. Practical adaptive quantum tomography

    Science.gov (United States)

    Granade, Christopher; Ferrie, Christopher; Flammia, Steven T.

    2017-11-01

    We introduce a fast and accurate heuristic for adaptive tomography that addresses many of the limitations of prior methods. Previous approaches were either too computationally intensive or tailored to handle special cases such as single qubits or pure states. By contrast, our approach combines the efficiency of online optimization with generally applicable and well-motivated data-processing techniques. We numerically demonstrate these advantages in several scenarios including mixed states, higher-dimensional systems, and restricted measurements. http://cgranade.com complete data and source code for this work are available online [1], and can be previewed at https://goo.gl/koiWxR.

  8. Computed tomography of surface related radionuclide distributions ('BONN'-tomography)

    International Nuclear Information System (INIS)

    Bockisch, A.; Koenig, R.

    1989-01-01

    A method called the 'BONN' tomography is described to produce planar projections of circular activity distributions using standard single photon emission computed tomography. The clinical value of the method is demonstrated for bone scans of the jaw, thorax, and pelvis. Numerical or projection-related problems are discussed. (orig.) [de

  9. Accuracy of volumetric measurement of simulated root resorption lacunas based on cone beam computed tomography.

    Science.gov (United States)

    Wang, Y; He, S; Guo, Y; Wang, S; Chen, S

    2013-08-01

    To evaluate the accuracy of volumetric measurement of simulated root resorption cavities based on cone beam computed tomography (CBCT), in comparison with that of Micro-computed tomography (Micro-CT) which served as the reference. The State Key Laboratory of Oral Diseases at Sichuan University. Thirty-two bovine teeth were included for standardized CBCT scanning and Micro-CT scanning before and after the simulation of different degrees of root resorption. The teeth were divided into three groups according to the depths of the root resorption cavity (group 1: 0.15, 0.2, 0.3 mm; group 2: 0.6, 1.0 mm; group 3: 1.5, 2.0, 3.0 mm). Each depth included four specimens. Differences in tooth volume before and after simulated root resorption were then calculated from CBCT and Micro-CT scans, respectively. The overall between-method agreement of the measurements was evaluated using the concordance correlation coefficient (CCC). For the first group, the average volume of resorption cavity was 1.07 mm(3) , and the between-method agreement of measurement for the volume changes was low (CCC = 0.098). For the second and third groups, the average volumes of resorption cavities were 3.47 and 6.73 mm(3) respectively, and the between-method agreements were good (CCC = 0.828 and 0.895, respectively). The accuracy of 3-D quantitative volumetric measurement of simulated root resorption based on CBCT was fairly good in detecting simulated resorption cavities larger than 3.47 mm(3), while it was not sufficient for measuring resorption cavities smaller than 1.07 mm(3) . This method could be applied in future studies of root resorption although further studies are required to improve its accuracy. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Development of a simple photon emission computed tomography dedicated to the small animal

    International Nuclear Information System (INIS)

    Bekaert, V.

    2006-11-01

    The development of in vivo small animal imaging becomes essential to study human pathologies. The ImaBio project of Institut Pluridisciplinaire Hubert Curien (IPHC) fits in the process of developing new instruments for biomedical applications with the development of a multimodality imaging platform dedicated to small animal imaging (AMISSA). This thesis presents the study, the design and the development of a Single Photon Emission Computed Tomography (SPECT) which will be integrated to the AMISSA platform. The result of these developments is the possibility to obtain the spatial distribution of an injected molecule into the animal. The SPECT technical solutions are based on the acquired knowledge of the institute allowing the conception of a device with cameras adapted to the gamma detection produced by the radiotracers used in single photon imaging. In order to cover the entire of the transverse field of view, four gamma cameras are arranged in a ring around the volume of interest. Each camera consists of 5 individual modules based on a YAP:Ce crystal array, a multi-anode photomultiplier and a dedicated multichannel electronic device. Finally, 20 detection modules were calibrated to give the same result for an identical energy deposit. The data are acquired then process to extract the positions and the energies deposited by gamma photons in the crystals. This last information is then gathered to build the projections. The 3D reconstructed image from the projections is carried out by the sequence of two algorithms, analytical and iterative OS-EM, both modified to take into account the singular geometry of our detection system. Finally, the obtained image is fused with the anatomical information given by the micro Computed Tomography system. (author)

  11. Development of novel emission tomography system

    Science.gov (United States)

    Fu, Geng

    In recent years, small animals, such as mice and rats, have been widely used as subjects of study in biomedical research while molecular biology and imaging techniques open new opportunities to investigate disease model. With the help of medical imaging techniques, researchers can investigate underlying mechanisms inside the small animal, which are useful for both early diagnosis and treatment monitoring. Based on tracer principle single photon emission computed tomography (SPECT) has increased popularity in small animal imaging due to its higher spatial resolution and variety of single-photon emitting radionuclides. Since the image quality strongly depends on the detector properties, both scintillation and semiconductor detectors are under active investigation for high resolution X-ray and gamma ray photon detection. The desired detector properties include high intrinsic spatial resolution, high energy resolution, and high detection efficiency. In this thesis study, we have made extensive efforts to develop novel emission tomography system, and evaluate the use of both semiconductor and ultra-high resolution scintillation detectors for small animal imaging. This thesis work includes the following three areas. Firstly, we have developed a novel energy-resolved photon counting (ERPC) detector. With the benefits of high energy resolution, high spatial resolution, flexible detection area, and a wide dynamic range of 27--200keV, ERPC detector is well-suited for small animal SPECT applications. For prototype ERPC detector excellent imaging (˜350microm) and spectroscopic performance (4keV Co-57 122keV) has been demonstrated in preliminary study. Secondly, to further improve spatial resolution to hundred-micron level, an ultra-high resolution Intensified EMCCD (I-EMCCD) detector has been designed and evaluated. This detector consists of the newly developed electron multiplying CCD (EMCCD) sensor, columnar CsI(Tl) scintillator, and an electrostatic de-magnifier (DM) tube

  12. Auroral Tomography Workshop, Proceedings

    International Nuclear Information System (INIS)

    Steen, Aa.

    1993-08-01

    In ionospheric and atmospheric physics the importance of multi-station imaging has grown as a consequence of the availability of scientific grade CCD cameras with digital output and affordable massive computing power. Tomographic inversion techniques are used in many different areas, e.g. medicine, plasma research and space physics. The tomography workshop was announced to gather a limited group of people interested in auroral tomography or tomographic inversion methods in general. ALIS (Auroral Large Imaging System) is a multi-station ground-based system developed primarily for three-dimensional auroral imaging, however other non-auroral objects can be studied with ALIS, e.g. stratospheric clouds. Several of the contributions in the workshop dealt with problems related to geometries similar to the ALIS-configuration. The Proceedings contain written contributions received either in abstract form or as full papers. The Proceedings also contain contributions intended for the Workshop but not presented due to the absence of the speaker. Separate abstracts have been prepared for 15 of the 17 papers

  13. Compressed sensing electron tomography

    International Nuclear Information System (INIS)

    Leary, Rowan; Saghi, Zineb; Midgley, Paul A.; Holland, Daniel J.

    2013-01-01

    The recent mathematical concept of compressed sensing (CS) asserts that a small number of well-chosen measurements can suffice to reconstruct signals that are amenable to sparse or compressible representation. In addition to powerful theoretical results, the principles of CS are being exploited increasingly across a range of experiments to yield substantial performance gains relative to conventional approaches. In this work we describe the application of CS to electron tomography (ET) reconstruction and demonstrate the efficacy of CS–ET with several example studies. Artefacts present in conventional ET reconstructions such as streaking, blurring of object boundaries and elongation are markedly reduced, and robust reconstruction is shown to be possible from far fewer projections than are normally used. The CS–ET approach enables more reliable quantitative analysis of the reconstructions as well as novel 3D studies from extremely limited data. - Highlights: • Compressed sensing (CS) theory and its application to electron tomography (ET) is described. • The practical implementation of CS–ET is outlined and its efficacy demonstrated with examples. • High fidelity tomographic reconstruction is possible from a small number of images. • The CS–ET reconstructions can be more reliably segmented and analysed quantitatively. • CS–ET is applicable to different image content by choice of an appropriate sparsifying transform

  14. Positron emission tomography. Positronemisionstomografi

    Energy Technology Data Exchange (ETDEWEB)

    Bolwig, T G; Haunsoe, S; Dahlgaard Hove, J; Hesse, B; Hoejgard, L; Jensen, M; Paulson, O B; Hastrup Svendsen, J; Soelvsten Soerensen, S

    1994-10-01

    Positron emission tomography (PET) is a method for quantitative imaging of regional physiological and biochemical parameters. Positron emitting radioactive isotopes can be produced by a cyclotron, eg. the biologically important carbon ([sup 11]C), oxygen ([sup 15]O), and nitrogen ([sup 13]N) elements. With the tomographic principles of the PET scanner the quantitative distribution of the administered isotopes can be determined and images can be provided as well as dynamic information on blood flow, metabolism and receptor function. In neurology PET has been used for investigations on numerous physiological processes in the brain: circulation, metabolism and receptor studies. In Parkinson's disease PET studies have been able to localize the pathology specifically, and in early stroke PET technique can outline focal areas with living but non-functioning cells, and this could make it possible to intervene in this early state. With positron emission tomography a quantitative evaluation of myocardial blood flow, glucose and fatty acid metabolism can be made as well as combined assessments of blood flow and metabolism. Combined studies of blood flow and metabolism can determine whether myocardial segments with abnormal motility consist of necrotic or viable tissue, thereby delineating effects of revascularisation. In the future it will probably be possible to characterize the myocardial receptor status in different cardiac diseases. The PET technique is used in oncology for clinical as well as more basic research on tumor perfusion and metabolism. Further, tumor uptake of positron labelled cytotoxic drugs might predict the clinical benefit of treatment. (au) (19 refs.).

  15. Waste inspection tomography (WIT)

    Energy Technology Data Exchange (ETDEWEB)

    Bernardi, R.T. [Bio-Imaging Research, Inc., Lincolnshire, IL (United States)

    1995-10-01

    Waste Inspection Tomography (WIT) provides mobile semi-trailer mounted nondestructive examination (NDE) and assay (NDA) for nuclear waste drum characterization. WIT uses various computed tomography (CT) methods for both NDE and NDA of nuclear waste drums. Low level waste (LLW), transuranic (TRU), and mixed radioactive waste can be inspected and characterized without opening the drums. With externally transmitted x-ray NDE techniques, WIT has the ability to identify high density waste materials like heavy metals, define drum contents in two- and three-dimensional space, quantify free liquid volumes through density and x-ray attenuation coefficient discrimination, and measure drum wall thickness. With waste emitting gamma-ray NDA techniques, WIT can locate gamma emitting radioactive sources in two- and three-dimensional space, identify gamma emitting, isotopic species, identify the external activity levels of emitting gamma-ray sources, correct for waste matrix attenuation, provide internal activity approximations, and provide the data needed for waste classification as LLW or TRU.

  16. Transverse tomography and radiotherapy

    International Nuclear Information System (INIS)

    Leer, J.W.H.

    1982-01-01

    This study was intended to delineate the indications for radiotherapy treatment-planning with the help of computerized axial tomography (C.T.) and transverse analog tomography (T.A.T.). Radiotherapy localisation procedures with the conventional method (simulator), with the CT-scanner and with the transverse analog tomograph (T.A.T., Simtomix, Oldelft) were compared. As criterium for evaluation differences in reconstruction drawing based on these methods were used. A certain method was judged ''superior'' to another if the delineation of the target volume was more accurate, if a better impression was gained of the site of (for irradiation) organs at risk, or if the localisation could only be performed with that method. The selected group of patients consisted of 120 patients for whom a reconstruction drawing in the transverse plane was made according to the treatment philosophy. In this group CT-assisted localisation was judged on 68 occasions superior to the conventional method. In a number of cases it was found that a ''standard'' change in a standard target volume, on the base of augmented anatomical knowledge, made the conventional method sufficient. The use of CT-scanner for treatment planning was estimated. For ca. 270/1000 new patients a CT-scan is helpful (diagnostic scan), for 140 of them the scan is necessary (planning scan). The quality of the anatomical information obtained with the T.A.T. does not yet fall within acceptable limits, but progress has been made. (Auth.)

  17. Positron emission tomography

    International Nuclear Information System (INIS)

    Bolwig, T.G.; Haunsoe, S.; Dahlgaard Hove, J.; Hesse, B.; Hoejgard, L.; Jensen, M.; Paulson, O.B.; Hastrup Svendsen, J.; Soelvsten Soerensen, S.

    1994-01-01

    Positron emission tomography (PET) is a method for quantitative imaging of regional physiological and biochemical parameters. Positron emitting radioactive isotopes can be produced by a cyclotron, eg. the biologically important carbon ( 11 C), oxygen ( 15 O), and nitrogen ( 13 N) elements. With the tomographic principles of the PET scanner the quantitative distribution of the administered isotopes can be determined and images can be provided as well as dynamic information on blood flow, metabolism and receptor function. In neurology PET has been used for investigations on numerous physiological processes in the brain: circulation, metabolism and receptor studies. In Parkinson's disease PET studies have been able to localize the pathology specifically, and in early stroke PET technique can outline focal areas with living but non-functioning cells, and this could make it possible to intervene in this early state. With positron emission tomography a quantitative evaluation of myocardial blood flow, glucose and fatty acid metabolism can be made as well as combined assessments of blood flow and metabolism. Combined studies of blood flow and metabolism can determine whether myocardial segments with abnormal motility consist of necrotic or viable tissue, thereby delineating effects of revascularisation. In the future it will probably be possible to characterize the myocardial receptor status in different cardiac diseases. The PET technique is used in oncology for clinical as well as more basic research on tumor perfusion and metabolism. Further, tumor uptake of positron labelled cytotoxic drugs might predict the clinical benefit of treatment. (au) (19 refs.)

  18. Waste inspection tomography (WIT)

    International Nuclear Information System (INIS)

    Bernardi, R.T.

    1995-01-01

    Waste Inspection Tomography (WIT) provides mobile semi-trailer mounted nondestructive examination (NDE) and assay (NDA) for nuclear waste drum characterization. WIT uses various computed tomography (CT) methods for both NDE and NDA of nuclear waste drums. Low level waste (LLW), transuranic (TRU), and mixed radioactive waste can be inspected and characterized without opening the drums. With externally transmitted x-ray NDE techniques, WIT has the ability to identify high density waste materials like heavy metals, define drum contents in two- and three-dimensional space, quantify free liquid volumes through density and x-ray attenuation coefficient discrimination, and measure drum wall thickness. With waste emitting gamma-ray NDA techniques, WIT can locate gamma emitting radioactive sources in two- and three-dimensional space, identify gamma emitting, isotopic species, identify the external activity levels of emitting gamma-ray sources, correct for waste matrix attenuation, provide internal activity approximations, and provide the data needed for waste classification as LLW or TRU

  19. Computer tomography of the neurocranium.

    Science.gov (United States)

    Liliequist, B; Forssell, A

    1976-07-01

    The experience with computer tomography of the neurocranium in 300 patients submitted for computer tomography of the brain is reported. The more appropriate projections which may be obtained with the second generation of scanners in combination with an elaborated reconstruction technique seem to constitute a replacement of conventional skull films.

  20. [Computed tomography of the heart

    DEFF Research Database (Denmark)

    Kristensen, T.S.; Kofoed, K.F.; der, Recke P. von

    2009-01-01

    Noninvasive evaluation of the coronary arteries by multi-detector row computed tomography is a promising new alternative to conventional invasive coronary angiography. This article describes the technical background, methods, limitations and clinical applications and reviews current literature...... that compares the diagnostic accuracy of multi-detector row computed tomography with that of coronary angiography Udgivelsesdato: 2009/4/6...

  1. EDITORIAL: Industrial Process Tomography

    Science.gov (United States)

    Anton Johansen, Geir; Wang, Mi

    2008-09-01

    There has been tremendous development within measurement science and technology over the past couple of decades. New sensor technologies and compact versatile signal recovery electronics are continuously expanding the limits of what can be measured and the accuracy with which this can be done. Miniaturization of sensors and the use of nanotechnology push these limits further. Also, thanks to powerful and cost-effective computer systems, sophisticated measurement and reconstruction algorithms previously only accessible in advanced laboratories are now available for in situ online measurement systems. The process industries increasingly require more process-related information, motivated by key issues such as improved process control, process utilization and process yields, ultimately driven by cost-effectiveness, quality assurance, environmental and safety demands. Industrial process tomography methods have taken advantage of the general progress in measurement science, and aim at providing more information, both quantitatively and qualitatively, on multiphase systems and their dynamics. The typical approach for such systems has been to carry out one local or bulk measurement and assume that this is representative of the whole system. In some cases, this is sufficient. However, there are many complex systems where the component distribution varies continuously and often unpredictably in space and time. The foundation of industrial tomography is to conduct several measurements around the periphery of a multiphase process, and use these measurements to unravel the cross-sectional distribution of the process components in time and space. This information is used in the design and optimization of industrial processes and process equipment, and also to improve the accuracy of multiphase system measurements in general. In this issue we are proud to present a selection of the 145 papers presented at the 5th World Congress on Industrial Process Tomography in Bergen

  2. Proton computed tomography

    International Nuclear Information System (INIS)

    Hanson, K.M.

    1978-01-01

    The use of protons or other heavy charged particles instead of x rays in computed tomography (CT) is explored. The results of an experimental implementation of proton CT are presented. High quality CT reconstructions are obtained at an average dose reduction factor compared with an EMI 5005 x-ray scanner of 10:1 for a 30-cm-diameter phantom and 3.5:1 for a 20-cm diameter. The spatial resolution is limited by multiple Coulomb scattering to about 3.7 mm FWHM. Further studies are planned in which proton and x-ray images of fresh human specimens will be compared. Design considerations indicate that a clinically useful proton CT scanner is eminently feasible

  3. The neutron computer tomography

    International Nuclear Information System (INIS)

    Matsumoto, G.; Krata, S.

    1983-01-01

    The method of computer tomography (CT) was applied for neutrons instead of X-rays. The neutron radiography image of samples was scanned by microphotometer to get the transmission data. This process was so time-consuming that the number of incident angles to samples could not be increased. The transmission data was processed by FACOM computer and CT image was gained. In the experiment at the Japan Research Reactor No. 4 at Tokai-mura with 18 projection angles, the resolution of paraffin in the aluminum block was less than 0.8 mm. In the experiment at Van de Graaf accelerator of Nagoya University, this same resolution was 1.2 mm because of the angle distribution of neutron beam. This experiment is the preliminary one, the facility which utilizes neutron television and video-recorder will be necessary for the next stage. (Auth.)

  4. Emission computed tomography

    International Nuclear Information System (INIS)

    Phelps, M.E.

    1977-01-01

    Although there are many common aspects to x-ray transmission and radionuclide emission (ECT) computerized tomography, there are added difficulties and a number of particular factors which form the basis of ECT. The relationship between the physical factors, system design, methodologic approach and assumptions of ECT is discussed. The instrumentation design and application strategies in ECT at this time are diverse and in a rapid stage of development. The approaches are divided into two major categories of Single Photon Counting (SPC) employing scanner and camera concepts with radionuclides of 99 /sup m/Tc, 201 Tl, 123 I etc., and Annihilation Coincidence Detection (ACD) of positron-emitting radionuclides. Six systems in the former and ten systems in the latter category, with examples of typical studies, illustrate the different approaches

  5. Tomography by positrons emission

    International Nuclear Information System (INIS)

    Mosconi, Sergio L.

    1999-01-01

    The tomography by positrons emission is a technology that allows to measure the concentration of positrons emission in a tri dimensional body through external measurements. Among the isotope emissions have carbon isotopes are ( 11 C), of the oxygen ( 15 O), of the nitrogen ( 13 N) that are three the element that constitute the base of the organic chemistry. Theses have on of the PET's most important advantages, since many biological interesting organic molecules can be tracer with these isotopes for the metabolism studies 'in vivo' through PET, without using organic tracers that modify the metabolism. The mentioned isotopes, also possess the characteristic of having short lifetime, that constitute on of PET's advantages from the dosimetric point of view. Among 11 C, 15 O, and 13 N, other isotopes that can be obtained of a generator as the 68 Ga and 82 Rb

  6. Positron emission computed tomography

    International Nuclear Information System (INIS)

    Grover, M.; Schelbert, H.R.

    1985-01-01

    Regional mycardial blood flow and substrate metabolism can be non-invasively evaluated and quantified with positron emission computed tomography (Positron-CT). Tracers of exogenous glucose utilization and fatty acid metabolism are available and have been extensively tested. Specific tracer kinetic models have been developed or are being tested so that glucose and fatty acid metabolism can be measured quantitatively by Positron-CT. Tracers of amino acid and oxygen metabolism are utilized in Positron-CT studies of the brain and development of such tracers for cardiac studies are in progress. Methods to quantify regional myocardial blood flow are also being developed. Previous studies have demonstrated the ability of Positron-/CT to document myocardial infarction. Experimental and clinical studies have begun to identify metabolic markers of reversibly ischemic myocardium. The potential of Positron-CT to reliably detect potentially salvageable myocardium and, hence, to identify appropriate therapeutic interventions is one of the most exciting applications of the technique

  7. Positron emission tomography camera

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    A positron emission tomography camera having a plurality of detector planes positioned side-by-side around a patient area to detect radiation. Each plane includes a plurality of photomultiplier tubes and at least two rows of scintillation crystals on each photomultiplier tube extend across to adjacent photomultiplier tubes for detecting radiation from the patient area. Each row of crystals on each photomultiplier tube is offset from the other rows of crystals, and the area of each crystal on each tube in each row is different than the area of the crystals on the tube in other rows for detecting which crystal is actuated and allowing the detector to detect more inter-plane slides. The crystals are offset by an amount equal to the length of the crystal divided by the number of rows. The rows of crystals on opposite sides of the patient may be rotated 90 degrees relative to each other

  8. Gantry for computed tomography

    International Nuclear Information System (INIS)

    Kelman, A.L.; O'Dell, W.R.; Brook, R.F.; Hein, P.W.; Brandt, R.T.

    1981-01-01

    A novel design of gantry for use in computed tomography is described in detail. In the new gantry, curved tracks are mounted to the laterally spaced apart sides of the frame which rotates and carries the detector and X-ray source. This permits the frame to be tilted either side of vertical enabling angular slices of body layers to be viewed and allows simplification of the algorithm which the computer uses for image reconstruction. A failsafe, solenoid brake is described which can lock the shaft against rotation. The gantry also contains a hoist mechanism which aids maintenance of the heavy X-ray tube and/or detector arrays. Explicit engineering details are presented. (U.K.)

  9. Positron emission tomography camera

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    A positron emission tomography camera having a plurality of detector rings positioned side-by-side or offset by one-half of the detector cross section around a patient area to detect radiation therefrom. Each ring contains a plurality of scintillation detectors which are positioned around an inner circumference with a septum ring extending inwardly from the inner circumference along each outer edge of each ring. An additional septum ring is positioned in the middle of each ring of detectors and parallel to the other septa rings, whereby the inward extent of all the septa rings may be reduced by one-half and the number of detectors required in each ring is reduced. The additional septa reduces the costs of the positron camera and improves its performance

  10. Positron emission tomography camera

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    A positron emission tomography camera having a plurality of detector rings positioned side-by-side or offset by one-half of the detector cross section around a patient area to detect radiation therefrom. Each detector ring or offset ring includes a plurality of photomultiplier tubes and a plurality of scintillation crystals are positioned relative to the photomultiplier tubes whereby each tube is responsive to more than one crystal. Each alternate crystal in the ring is offset by one-half or less of the thickness of the crystal such that the staggered crystals are seen by more than one photomultiplier tube. This sharing of crystals and photomultiplier tubes allows identification of the staggered crystal and the use of smaller detectors shared by larger photomultiplier tubes thereby requiring less photomultiplier tubes, creating more scanning slices, providing better data sampling, and reducing the cost of the camera. The offset detector ring geometry reduces the costs of the positron camera and improves its performance

  11. Optical Coherence Tomography

    DEFF Research Database (Denmark)

    Fercher, A.F.; Andersen, Peter E.

    2017-01-01

    Optical coherence tomography (OCT) is a technique that is used to peer inside a body noninvasively. Tissue structure defined by tissue absorption and scattering coefficients, and the speed of blood flow, are derived from the characteristics of light remitted by the body. Singly backscattered light...... detected by partial coherence interferometry (PCI) is used to synthesize the tomographic image coded in false colors. A prerequisite of this technique is a low time-coherent but high space-coherent light source, for example, a superluminescent diode or a supercontinuum source. Alternatively, the imaging...... technique can be realized by using ultrafast wavelength scanning light sources. For tissue imaging, the light source wavelengths are restricted to the red and near-infrared (NIR) region from about 600 to 1300 nm, the so-called therapeutic window, where absorption (μa ≈ 0.01 mm−1) is small enough. Transverse...

  12. Projection radiography and tomography

    International Nuclear Information System (INIS)

    Tobias, C.A.; Fabrikant, J.I.; Benton, E.V.; Holley, W.R.

    1980-01-01

    Our program on heavy-ion radiography began soon after heavy ions were accelerated to high energies. Heavy ions are capable of very high electron density discrimination combined with good radial image resolution and low dose. Since heavy-ion beams produce many secondries, plastic nuclear detectors have an advantage for recording heavy-ion images. Projection imaging is now a practical technique that can resolve density differences between normal tissue and tumor tissue in some cases in which X rays could not make a distinction. Initial attempts at heavy-ion tomography also indicate potential for high resolution in this field. The physical basis for heavy-ion radiography and tomographic reconstruction studies are discussed in detail

  13. Improving limited-projection-angle fluorescence molecular tomography using a co-registered x-ray computed tomography scan.

    Science.gov (United States)

    Radrich, Karin; Ale, Angelique; Ermolayev, Vladimir; Ntziachristos, Vasilis

    2012-12-01

    We examine the improvement in imaging performance, such as axial resolution and signal localization, when employing limited-projection-angle fluorescence molecular tomography (FMT) together with x-ray computed tomography (XCT) measurements versus stand-alone FMT. For this purpose, we employed living mice, bearing a spontaneous lung tumor model, and imaged them with FMT and XCT under identical geometrical conditions using fluorescent probes for cancer targeting. The XCT data was employed, herein, as structural prior information to guide the FMT reconstruction. Gold standard images were provided by fluorescence images of mouse cryoslices, providing the ground truth in fluorescence bio-distribution. Upon comparison of FMT images versus images reconstructed using hybrid FMT and XCT data, we demonstrate marked improvements in image accuracy. This work relates to currently disseminated FMT systems, using limited projection scans, and can be employed to enhance their performance.

  14. Waste Inspection Tomography (WIT)

    International Nuclear Information System (INIS)

    Bernardi, R.T.

    1995-01-01

    Waste Inspection Tomography (WIT) provides mobile semi-trailer mounted nondestructive examination (NDE) and assay (NDA) for nuclear waste drum characterization. WIT uses various computed tomography (CT) methods for both NDE and NDA of nuclear waste drums. Low level waste (LLW), transuranic (TRU), and mixed radioactive waste can be inspected and characterized without opening the drums. With externally transmitted x-ray NDE techniques, WIT has the ability to identify high density waste materials like heavy metals, define drum contents in two- and three-dimensional space, quantify free liquid volumes through density and x-ray attenuation coefficient discrimination, and measure drum wall thickness. With waste emitting gamma-ray NDA techniques, WIT can locate gamma emitting radioactive sources in two- and three-dimensional space, identify gamma emitting isotopic species, identify the external activity levels of emitting gamma-ray sources, correct for waste matrix attenuation, provide internal activity approximations, and provide the data needed for waste classification as LLW or TRU. The mobile feature of WIT allows inspection technologies to be brought to the nuclear waste drum storage site without the need to relocate drums for safe, rapid, and cost-effective characterization of regulated nuclear waste. The combination of these WIT characterization modalities provides the inspector with an unprecedented ability to non-invasively characterize the regulated contents of waste drums as large as 110 gallons, weighing up to 1,600 pounds. Any objects that fit within these size and weight restrictions can also be inspected on WIT, such as smaller waste bags and drums that are five and thirty-five gallons

  15. Ocean acoustic tomography

    International Nuclear Information System (INIS)

    Cornuelle, Bruce D; Worcester, Peter F; Dzieciuch, Matthew A

    2008-01-01

    Ocean acoustic tomography (OAT) was proposed in 1979 by Walter Munk and Carl Wunsch as an analogue to x-ray computed axial tomography for the oceans. The oceans are opaque to most electromagnetic radiation, but there is a strong acoustic waveguide, and sound can propagate for 10 Mm and more with distinct multiply-refracted ray paths. Transmitting broadband pulses in the ocean leads to a set of impulsive arrivals at the receiver which characterize the impulse response of the sound channel. The peaks observed at the receiver are assumed to represent the arrival of energy traveling along geometric ray paths. These paths can be distinguished by arrival time, and by arrival angle when a vertical array of receivers is available. Changes in ray arrival time can be used to infer changes in ocean structure. Ray travel time measurements have been a mainstay of long-range acoustic measurements, but the strong sensitivity of ray paths to range-dependent sound speed perturbations makes the ray sampling functions uncertain in real cases. In the ray approximation travel times are sensitive to medium changes only along the corresponding eigenrays. Ray theory is an infinite-frequency approximation, and its eikonal equation has nonlinearities not found in the acoustic wave equation. We build on recent seismology results (kernels for body wave arrivals in the earth) to characterize the kernel for converting sound speed change in the ocean to travel time changes using more complete propagation physics. Wave-theoretic finite frequency kernels may show less sensitivity to small-scale sound speed structure.

  16. Mechanical Forces Exacerbate Periodontal Defects in Bsp-null Mice

    Science.gov (United States)

    Soenjaya, Y.; Foster, B.L.; Nociti, F.H.; Ao, M.; Holdsworth, D.W.; Hunter, G.K.; Somerman, M.J.

    2015-01-01

    Bone sialoprotein (BSP) is an acidic phosphoprotein with collagen-binding, cell attachment, and hydroxyapatite-nucleating properties. BSP expression in mineralized tissues is upregulated at onset of mineralization. Bsp-null (Bsp-/-) mice exhibit reductions in bone mineral density, bone turnover, osteoclast activation, and impaired bone healing. Furthermore, Bsp-/- mice have marked periodontal tissue breakdown, with a lack of acellular cementum leading to periodontal ligament detachment, extensive alveolar bone and tooth root resorption, and incisor malocclusion. We hypothesized that altered mechanical stress from mastication contributes to periodontal destruction observed in Bsp-/- mice. This hypothesis was tested by comparing Bsp-/- and wild-type mice fed with standard hard pellet diet or soft powder diet. Dentoalveolar tissues were analyzed using histology and micro–computed tomography. By 8 wk of age, Bsp-/- mice exhibited molar and incisor malocclusion regardless of diet. Bsp-/- mice with hard pellet diet exhibited high incidence (30%) of severe incisor malocclusion, 10% lower body weight, 3% reduced femur length, and 30% elevated serum alkaline phosphatase activity compared to wild type. Soft powder diet reduced severe incisor malocclusion incidence to 3% in Bsp-/- mice, supporting the hypothesis that occlusal loading contributed to the malocclusion phenotype. Furthermore, Bsp-/- mice in the soft powder diet group featured normal body weight, long bone length, and serum alkaline phosphatase activity, suggesting that tooth dysfunction and malnutrition contribute to growth and skeletal defects reported in Bsp-/- mice. Bsp-/- incisors also erupt at a slower rate, which likely leads to the observed thickened dentin and enhanced mineralization of dentin and enamel toward the apical end. We propose that the decrease in eruption rate is due to a lack of acellular cementum and associated defective periodontal attachment. These data demonstrate the importance of BSP

  17. Magnetic resonance tomography in syringomyelia

    International Nuclear Information System (INIS)

    Koehler, D.; Treisch, J.; Hertel, G.; Schoerner, W.; Fiegler, W.; Staedtisches Rudolf-Virchow Krankenhaus, Berlin

    1985-01-01

    Thirteen patients with a clinical diagnosis of syringomyelia were examined by nuclear tomography (0.35 T magnet) in the spin-echo mode. In all thirteen patients, the T1 images (Se 400/35) showed a longitudinal cavity with a signal intensity of CSF. The shape and extent of the syrinx could be adequately demonstrated in 12 of the 13 examinations. Downward displacement of the cerebellar tonsils was seen in eight cases. The examination took between half and one hour. Advantages of magnetic resonance tomography (nuclear tomography) include the absence of artifacts, images in the line of the lesion and its non-invasiveness. (orig.) [de

  18. Computed tomography of the pancreas

    International Nuclear Information System (INIS)

    Kolmannskog, F.; Kolbenstvedt, A.; Aakhus, T.; Bergan, A.; Fausa, O.; Elgjo, K.

    1980-01-01

    The findings by computed tomography in 203 cases of suspected pancreatic tumours, pancreatitis or peripancreatic abnormalities were evaluated. The appearances of the normal and the diseased pancreas are described. Computed tomography is highly accurate in detecting pancreatic masses, but can not differentiate neoplastic from inflammatory disease. The only reliable signs of pancreatic carcinoma are a focal mass in the pancreas, together with liver metastasis. When a pancreatic mass is revealed by computed tomography, CT-guided fine-needle aspiration biopsy of the pancreas is recommended. Thus the need for more invasive diagnostic procedures and explorative laparotomy may be avoided in some patients. (Auth.)

  19. Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography in Disseminated Cryptococcosis.

    Science.gov (United States)

    Tripathy, Sarthak; Parida, Girish Kumar; Roy, Shambo Guha; Singhal, Abhinav; Mallick, Saumya Ranjan; Tripathi, Madhavi; Shamim, Shamim Ahmed

    2017-01-01

    Disseminated cryptococcosis without pulmonary involvement is a very rare phenomenon. Patterns of organ involvement in cryptococcosis resemble various other infective conditions as well as malignant conditions on fluorodeoxyglucose positron emission tomography-computed tomography. We present a case of a 43-year-old male patient who had disseminated cryptococcosis. The rarity of the case being noninvolvement of lungs and meninges and resembling more like lymphoma due to the diffuse involvement of the lymph nodes on both sides of the diaphragm.

  20. Trabecular bone structure parameters from 3D image processing of clinical multi-slice and cone-beam computed tomography data

    Energy Technology Data Exchange (ETDEWEB)

    Klintstroem, Eva; Smedby, Oerjan [Linkoeping University, Center for Medical Image Science and Visualization (CMIV), Linkoeping (Sweden); UHL County Council of Oestergoetland, Department of Radiology, Linkoeping (Sweden); Linkoeping University, Department of Medical and Health Sciences (IMH)/Radiology, Linkoeping (Sweden); Moreno, Rodrigo [Linkoeping University, Center for Medical Image Science and Visualization (CMIV), Linkoeping (Sweden); Linkoeping University, Department of Medical and Health Sciences (IMH)/Radiology, Linkoeping (Sweden); Brismar, Torkel B. [KUS Huddinge, Department of Clinical Science, Intervention and Technology at Karolinska Institutet and Department of Radiology, Stockholm (Sweden)

    2014-02-15

    Bone strength depends on both mineral content and bone structure. The aim of this in vitro study was to develop a method of quantitatively assessing trabecular bone structure by applying three-dimensional image processing to data acquired with multi-slice and cone-beam computed tomography using micro-computed tomography as a reference. Fifteen bone samples from the radius were examined. After segmentation, quantitative measures of bone volume, trabecular thickness, trabecular separation, trabecular number, trabecular nodes, and trabecular termini were obtained. The clinical machines overestimated bone volume and trabecular thickness and underestimated trabecular nodes and number, but cone-beam CT to a lesser extent. Parameters obtained from cone beam CT were strongly correlated with μCT, with correlation coefficients between 0.93 and 0.98 for all parameters except trabecular termini. The high correlation between cone-beam CT and micro-CT suggest the possibility of quantifying and monitoring changes of trabecular bone microarchitecture in vivo using cone beam CT. (orig.)

  1. Parkinson disease and positron tomography

    International Nuclear Information System (INIS)

    Baron, J.C.

    1984-10-01

    Physiopathologic investigations of Parkinson disease and parkinsonian syndrome using positron tomography are briefly reviewed: study of cerebral blood flow and metabolism; effects of L-DOPA; study of dopaminergic receptors and of 18 F-Fluoro-L-DOPA incorporation [fr

  2. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... is Children's CT? Computed tomography, more commonly known as a CT or CAT scan, is a diagnostic ... is used to evaluate: complications from infections such as pneumonia a tumor that arises in the lung ...

  3. Computed tomography of drill cores

    International Nuclear Information System (INIS)

    Taylor, T.

    1985-08-01

    A preliminary computed tomography evaluation of drill cores of granite and sandstone has generated geologically significant data. Density variations as small as 4 percent and fractures as narrow as 0.1 mm were easily detected

  4. Computed tomography of pulmonary nodules

    International Nuclear Information System (INIS)

    Nakata, Hajime; Honda, Hiroshi; Nakayama, Chikashi; Kimoto, Tatsuya; Nakayama, Takashi

    1983-01-01

    We have evaluated the value of computed tomography (CT) in distinguishing benign and malignant pulmonary nodules. CT was performed on 30 cases of solitary pulmonary nodules consisting of 17 primary lung cancers, 3 metastatic tumors and 10 benign nodules. The CT number was calculated for each lesion. Three benign nodules showed CT numbers well above the range of malignant nodules, and only in one of them was calcification visible on conventional tomography. In 6 benign nodules, the CT numbers overlapped those of malignant lesion and could not be differentiated. Thus the measurement of CT number can be useful to confirm the benign nature of certain nodules when calcification is unclear or not visible on conventional tomography. As for the morphological observation of the nodule, CT was not superior to conventional tomography and its value seems to be limited. (author)

  5. Parsimonious Refraction Interferometry and Tomography

    KAUST Repository

    Hanafy, Sherif; Schuster, Gerard T.

    2017-01-01

    We present parsimonious refraction interferometry and tomography where a densely populated refraction data set can be obtained from two reciprocal and several infill shot gathers. The assumptions are that the refraction arrivals are head waves

  6. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... Children's (Pediatric) CT (Computed Tomography) Sponsored by Please note RadiologyInfo.org is not a medical facility. Please ... is further reviewed by committees from the American College of Radiology (ACR) and the Radiological Society of ...

  7. Computerized tomography in myotonic dystrophy

    International Nuclear Information System (INIS)

    Gellerich, I.; Mueller, D.; Koch, R.D.

    1986-01-01

    Besides clinical symptoms, progress and electromyography computerized tomography improves the diagnostics of myotonic dystrophy. Even small changes in muscular structure are detectable and especially the musculus soleus exhibits early and pronounced alterations. By means of density distribution pattern an improved characterization of the disease is possible. Additional information is obtained by cerebral computerized tomography. Atrophy of brain tissue is to be expected in all patients with myotonic dystrophy. (author)

  8. Attenuation Correction Strategies for Positron Emission Tomography/Computed Tomography and 4-Dimensional Positron Emission Tomography/Computed Tomography

    OpenAIRE

    Pan, Tinsu; Zaidi, Habib

    2013-01-01

    This article discusses attenuation correction strategies in positron emission tomography/computed tomography (PET/CT) and 4 dimensional PET/CT imaging. Average CT scan derived from averaging the high temporal resolution CT images is effective in improving the registration of the CT and the PET images and quantification of the PET data. It underscores list mode data acquisition in 4 dimensional PET and introduces 4 dimensional CT popular in thoracic treatment planning to 4 dimensional PET/CT. ...

  9. Neuroanatomy of cranial computed tomography

    International Nuclear Information System (INIS)

    Kretschmann, H.J.; Weinrich, W.

    1985-01-01

    Based on the fundamental structures visualized by means of computed tomography, the authors present the functional systems which are relevant in neurology by means of axial cross-sections. All drawings were prepared from original preparations by means of a new technique which is similar to the grey values of X-ray CT and nuclear magnetic resonance tomography. A detailed description is given of the topics of neurofunctional lesions

  10. Computed tomography apparatus

    International Nuclear Information System (INIS)

    Fairbairn, I.A.

    1984-01-01

    In fan-beam computed tomography apparatus, timing reference pulses, normally occurring at intervals t, for data transfer and reset of approx. 500 integrators in the signal path from the detector array, are generated from the scan displacement, e.g. using a graticule and optical sensor to relate the measurement paths geometrically to the body section. Sometimes, a slow scan rate is required to provide a time-averaged density image, e.g. for planning irradiation therapy, and then the sensed impulses will occur at extended intervals and can cause integrator overload. An improvement is described which provides a pulse generator which responds to a reduced scan rate by generating a succession of further transfer and reset pulses at intervals approximately equal to t starting a time t after each timing reference pulse. Then, using an adding device and RAM, all the transferred signals integrated in the interval t' between two successive slow scan reference pulses are accumulated in order to form a corresponding measurement signal. (author)

  11. Solar tomography adaptive optics.

    Science.gov (United States)

    Ren, Deqing; Zhu, Yongtian; Zhang, Xi; Dou, Jiangpei; Zhao, Gang

    2014-03-10

    Conventional solar adaptive optics uses one deformable mirror (DM) and one guide star for wave-front sensing, which seriously limits high-resolution imaging over a large field of view (FOV). Recent progress toward multiconjugate adaptive optics indicates that atmosphere turbulence induced wave-front distortion at different altitudes can be reconstructed by using multiple guide stars. To maximize the performance over a large FOV, we propose a solar tomography adaptive optics (TAO) system that uses tomographic wave-front information and uses one DM. We show that by fully taking advantage of the knowledge of three-dimensional wave-front distribution, a classical solar adaptive optics with one DM can provide an extra performance gain for high-resolution imaging over a large FOV in the near infrared. The TAO will allow existing one-deformable-mirror solar adaptive optics to deliver better performance over a large FOV for high-resolution magnetic field investigation, where solar activities occur in a two-dimensional field up to 60'', and where the near infrared is superior to the visible in terms of magnetic field sensitivity.

  12. Positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Lindback, Stig [GEMS PET Systems AB, Uppsala (Sweden)

    1995-07-15

    Positron Emission Tomography (PET) is an advanced nuclear medicine technique used for research at major centres. Unique diagnostic information is obtained from tomographic measurements of the biochemistry and physiology of tissues and organs. In theory, diseases are related to biochemical changes and these can be observed with PET long before any anatomical changes are detectable. In PET the radioactive component is a positron-emitting isotope or 'tracer'. The positrons annihilate with electrons in the body to produce two gamma rays 180° apart; coincidence detection of these gammas provides a very efficient method of determining the spatial distribution of the radioisotope tracer. Because physiological measurements are usually required in a single imaging session, very short-lived isotopes are used to label the tracer molecules; isotope production and labelling is usually carried out in situ. The most commonly used radionuclides are carbon- 11 (half-life 20 minutes), nitrogen-13 (10 minutes), oxygen-15 (2 minutes), and fluorine-18 (110 minutes). A PET system has three major components: - a particle accelerator with targets for production of the positron-emitting isotopes; - chemistry modules for synthesis and labelling of the desired tracers; - and a PET camera for in-vivo measurements of the distribution of the tracer in the body.

  13. Positron emission tomography

    International Nuclear Information System (INIS)

    Lindback, Stig

    1995-01-01

    Positron Emission Tomography (PET) is an advanced nuclear medicine technique used for research at major centres. Unique diagnostic information is obtained from tomographic measurements of the biochemistry and physiology of tissues and organs. In theory, diseases are related to biochemical changes and these can be observed with PET long before any anatomical changes are detectable. In PET the radioactive component is a positron-emitting isotope or 'tracer'. The positrons annihilate with electrons in the body to produce two gamma rays 180° apart; coincidence detection of these gammas provides a very efficient method of determining the spatial distribution of the radioisotope tracer. Because physiological measurements are usually required in a single imaging session, very short-lived isotopes are used to label the tracer molecules; isotope production and labelling is usually carried out in situ. The most commonly used radionuclides are carbon- 11 (half-life 20 minutes), nitrogen-13 (10 minutes), oxygen-15 (2 minutes), and fluorine-18 (110 minutes). A PET system has three major components: - a particle accelerator with targets for production of the positron-emitting isotopes; - chemistry modules for synthesis and labelling of the desired tracers; - and a PET camera for in-vivo measurements of the distribution of the tracer in the body

  14. Computed tomography intravenous cholangiography

    International Nuclear Information System (INIS)

    Nascimento, S.; Murray, W.; Wilson, P.

    1997-01-01

    Indications for direct visualization of the bile ducts include bile duct dilatation demonstrated by ultrasound or computed tomography (CT) scanning, where the cause of the bile duct dilatation is uncertain or where the anatomy of bile duct obstruction needs further clarification. Another indication is right upper quadrant pain, particularly in a post-cholecystectomy patient, where choledocholithiasis is suspected. A possible new indication is pre-operative evaluation prior to laparoscopic cholecystectomy. The bile ducts are usually studied by endoscopic retrograde cholangiopancreatography (ERCP), or, less commonly, trans-hepatic cholangiography. The old technique of intravenous cholangiography has fallen into disrepute because of inconsistent bile-duct opacification. The advent of spiral CT scanning has renewed interest in intravenous cholangiography. The CT technique is very sensitive to the contrast agent in the bile ducts, and angiographic and three-dimensional reconstructions of the biliary tree can readily be obtained using the CT intravenous cholangiogram technique (CT IVC). Seven patients have been studied using this CT IVC technique, between February 1995 and June 1996, and are the subject of the present report. Eight further studies have since been performed. The results suggest that CT IVC could replace ERCP as the primary means of direct cholangiography, where pancreatic duct visualization is not required. (authors)

  15. Multiphoton tomography of astronauts

    Science.gov (United States)

    König, Karsten; Weinigel, Martin; Pietruszka, Anna; Bückle, Rainer; Gerlach, Nicole; Heinrich, Ulrike

    2015-03-01

    Weightlessness may impair the astronaut's health conditions. Skin impairments belong to the most frequent health problems during space missions. Within the Skin B project, skin physiological changes during long duration space flights are currently investigated on three European astronauts that work for nearly half a year at the ISS. Measurements on the hydration, the transepidermal water loss, the surface structure, elasticity and the tissue density by ultrasound are conducted. Furthermore, high-resolution in vivo histology is performed by multiphoton tomography with 300 nm spatial and 200 ps temporal resolution. The mobile certified medical tomograph with a flexible 360° scan head attached to a mechano-optical arm is employed to measure two-photon autofluorescence and SHG in the volar forearm of the astronauts. Modification of the tissue architecture and of the fluorescent biomolecules NAD(P)H, keratin, melanin and elastin are detected as well as of SHG-active collagen. Thinning of the vital epidermis, a decrease of the autofluoresence intensity, an increase in the long fluorescence lifetime, and a reduced skin ageing index SAAID based on an increased collagen level in the upper dermis have been found. Current studies focus on recovery effects.

  16. Electrical impedance tomography

    Science.gov (United States)

    Lobo, Beatriz; Hermosa, Cecilia; Abella, Ana

    2018-01-01

    Continuous assessment of respiratory status is one of the cornerstones of modern intensive care unit (ICU) monitoring systems. Electrical impedance tomography (EIT), although with some constraints, may play the lead as a new diagnostic and guiding tool for an adequate optimization of mechanical ventilation in critically ill patients. EIT may assist in defining mechanical ventilation settings, assess distribution of tidal volume and of end-expiratory lung volume (EELV) and contribute to titrate positive end-expiratory pressure (PEEP)/tidal volume combinations. It may also quantify gains (recruitment) and losses (overdistention or derecruitment), granting a more realistic evaluation of different ventilator modes or recruitment maneuvers, and helping in the identification of responders and non-responders to such maneuvers. Moreover, EIT also contributes to the management of life-threatening lung diseases such as pneumothorax, and aids in guiding fluid management in the critical care setting. Lastly, assessment of cardiac function and lung perfusion through electrical impedance is on the way. PMID:29430443

  17. Extraction of fibre network architecture by X-ray tomography and prediction of elastic properties using an affine analytical model

    International Nuclear Information System (INIS)

    Tsarouchas, D.; Markaki, A.E.

    2011-01-01

    This paper proposes a method for extracting reliable architectural characteristics from complex porous structures using micro-computed tomography (μCT) images. The work focuses on a highly porous material composed of a network of fibres bonded together. The segmentation process, allowing separation of the fibres from the remainder of the image, is the most critical step in constructing an accurate representation of the network architecture. Segmentation methods, based on local and global thresholding, were investigated and evaluated by a quantitative comparison of the architectural parameters they yielded, such as the fibre orientation and segment length (sections between joints) distributions and the number of inter-fibre crossings. To improve segmentation accuracy, a deconvolution algorithm was proposed to restore the original images. The efficacy of the proposed method was verified by comparing μCT network architectural characteristics with those obtained using high resolution CT scans (nanoCT). The results indicate that this approach resolves the architecture of these complex networks and produces results approaching the quality of nanoCT scans. The extracted architectural parameters were used in conjunction with an affine analytical model to predict the axial and transverse stiffnesses of the fibre network. Transverse stiffness predictions were compared with experimentally measured values obtained by vibration testing.

  18. ELHnet: a convolutional neural network for classifying cochlear endolymphatic hydrops imaged with optical coherence tomography.

    Science.gov (United States)

    Liu, George S; Zhu, Michael H; Kim, Jinkyung; Raphael, Patrick; Applegate, Brian E; Oghalai, John S

    2017-10-01

    Detection of endolymphatic hydrops is important for diagnosing Meniere's disease, and can be performed non-invasively using optical coherence tomography (OCT) in animal models as well as potentially in the clinic. Here, we developed ELHnet, a convolutional neural network to classify endolymphatic hydrops in a mouse model using learned features from OCT images of mice cochleae. We trained ELHnet on 2159 training and validation images from 17 mice, using only the image pixels and observer-determined labels of endolymphatic hydrops as the inputs. We tested ELHnet on 37 images from 37 mice that were previously not used, and found that the neural network correctly classified 34 of the 37 mice. This demonstrates an improvement in performance from previous work on computer-aided classification of endolymphatic hydrops. To the best of our knowledge, this is the first deep CNN designed for endolymphatic hydrops classification.

  19. Of mice and men

    CERN Multimedia

    1973-01-01

    At the end of March , sixty mice were irradiated at the synchro-cyclotron in the course of an experimental programme studying radiation effects on mice and plants (Vicia faba bean roots) being carried out by the CERN Health Physics Group.

  20. The MICE Online Systems

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    The Muon Ionization Cooling Experiment (MICE) is designed to test transverse cooling of a muon beam, demonstrating an important step along the path toward creating future high intensity muon beam facilities. Protons in the ISIS synchrotron impact a titanium target, producing pions which decay into muons that propagate through the beam line to the MICE cooling channel. Along the beam line, particle identification (PID) detectors, scintillating fiber tracking detectors, and beam diagnostic tools identify and measure individual muons moving through the cooling channel. The MICE Online Systems encompass all tools; including hardware, software, and documentation, within the MLCR (MICE Local Control Room) that allow the experiment to efficiently record high quality data. Controls and Monitoring (C&M), Data Acquisition (DAQ), Online Monitoring and Reconstruction, Data Transfer, and Networking all fall under the Online Systems umbrella. C&M controls all MICE systems including the target, conventional an...

  1. Optical Coherence Tomography

    Directory of Open Access Journals (Sweden)

    Pier Alberto Testoni

    2007-01-01

    Full Text Available Optical coherence tomography (OCT is an optical imaging modality that performs high-resolution, cross-sectional, subsurface tomographic imaging of the microstructure of tissues. The physical principle of OCT is similar to that of B-mode ultrasound imaging, except that it uses infrared light waves rather than acoustic waves. The in vivo resolution is 10–25 times better (about 10 µm than with high-frequency ultrasound imaging, but the depth of penetration is limited to 1–3 mm, depending on tissue structure, depth of focus of the probe used, and pressure applied to the tissue surface. In the last decade, OCT technology has evolved from an experimental laboratory tool to a new diagnostic imaging modality with a wide spectrum of clinical applications in medical practice, including the gastrointestinal tract and pancreatico-biliary ductal system. OCT imaging from the gastrointestinal tract can be done in humans by using narrow-diameter, catheter-based probes that can be inserted through the accessory channel of either a conventional front-view endoscope, for investigating the epithelial structure of the gastrointestinal tract, or a side-view endoscope, inside a standard transparent ERCP (endoscopic retrograde cholangiopancreatography catheter, for investigating the pancreatico-biliary ductal system. The esophagus and esophagogastric junction have been the most widely investigated organs so far; more recently, duodenum, colon, and the pancreatico-biliary ductal system have also been extensively investigated. OCT imaging of the gastrointestinal wall structure is characterized by a multiple-layer architecture that permits an accurate evaluation of the mucosa, lamina propria, muscularis mucosae, and part of the submucosa. The technique may therefore be used to identify preneoplastic conditions of the gastrointestinal tract, such as Barrett's epithelium and dysplasia, and evaluate the depth of penetration of early-stage neoplastic lesions. OCT imaging

  2. Digital hilar tomography. Comparison with conventional technique

    International Nuclear Information System (INIS)

    Schaefer, C.B.; Braunschweig, R.; Teufl, F.; Kaiser, W.; Claussen, C.D.

    1993-01-01

    The aim of the following study was to compare conventional hilar tomography and digital hilar tomography. 20 patients were examined both with conventional and digital hilar tomography using the same tomographic technique and the identical exposure dose. All patients underwent computed tomography of the chest as a golden standard. The digital technique, especially the edge-enhanced image version, showed superior image quality. ROC-analysis by 4 readers found equal diagnostic performance without any statistical difference. Digital hilar tomography shows a superior and constant image quality and lowers the rate of re-exposure. Therefore, digital hilar tomography is the preferable method. (orig.) [de

  3. An introduction to emission computed tomography

    International Nuclear Information System (INIS)

    Williams, E.D.

    1985-01-01

    This report includes salient features of the theory and an examination of practical considerations for someone who is using or introducing tomography, selecting equipment for it or wishing to develop a clinical application. Emphasis is on gamma camera tomography. The subject is dealt with under the following headings: emission computed and gamma camera tomography and the relationship to other medical imaging techniques, the tomographic reconstruction technique theory, rotating gamma camera tomography, attenuation correction and quantitative reconstruction, other single photon tomographic techniques, positron tomography, image display, clinical application of single photon and positron tomography, and commercial systems for SPECT. Substantial bibliography. (U.K.)

  4. Three-dimensional hard and soft tissue imaging of the human cochlea by scanning laser optical tomography (SLOT.

    Directory of Open Access Journals (Sweden)

    Nadine Tinne

    Full Text Available The present study focuses on the application of scanning laser optical tomography (SLOT for visualization of anatomical structures inside the human cochlea ex vivo. SLOT is a laser-based highly efficient microscopy technique which allows for tomographic imaging of the internal structure of transparent specimens. Thus, in the field of otology this technique is best convenient for an ex vivo study of the inner ear anatomy. For this purpose, the preparation before imaging comprises decalcification, dehydration as well as optical clearing of the cochlea samples in toto. Here, we demonstrate results of SLOT imaging visualizing hard and soft tissue structures with an optical resolution of down to 15 μm using extinction and autofluorescence as contrast mechanisms. Furthermore, the internal structure can be analyzed nondestructively and quantitatively in detail by sectioning of the three-dimensional datasets. The method of X-ray Micro Computed Tomography (μCT has been previously applied to explanted cochlea and is solely based on absorption contrast. An advantage of SLOT is that it uses visible light for image formation and thus provides a variety of contrast mechanisms known from other light microscopy techniques, such as fluorescence or scattering. We show that SLOT data is consistent with μCT anatomical data and provides additional information by using fluorescence. We demonstrate that SLOT is applicable for cochlea with metallic cochlear implants (CI that would lead to significant artifacts in μCT imaging. In conclusion, the present study demonstrates the capability of SLOT for resolution visualization of cleared human cochleae ex vivo using multiple contrast mechanisms and lays the foundation for a broad variety of additional studies.

  5. Microstructural analysis of TRISO particles using multi-scale X-ray computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Lowe, T., E-mail: tristan.lowe@manchester.ac.uk [Manchester X-ray Imaging Facility, School of Materials, University of Manchester, M13 9PL (United Kingdom); Bradley, R.S. [Manchester X-ray Imaging Facility, School of Materials, University of Manchester, M13 9PL (United Kingdom); Yue, S. [Manchester X-ray Imaging Facility, School of Materials, University of Manchester, M13 9PL (United Kingdom); The Research Complex at Harwell, Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0FA (United Kingdom); Barii, K. [School of Mechanical Engineering, University of Manchester, M13 9PL (United Kingdom); Gelb, J. [Zeiss Xradia Inc., Pleasanton, CA (United States); Rohbeck, N. [Manchester X-ray Imaging Facility, School of Materials, University of Manchester, M13 9PL (United Kingdom); Turner, J. [School of Mechanical Engineering, University of Manchester, M13 9PL (United Kingdom); Withers, P.J. [Manchester X-ray Imaging Facility, School of Materials, University of Manchester, M13 9PL (United Kingdom); The Research Complex at Harwell, Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0FA (United Kingdom)

    2015-06-15

    TRISO particles, a composite nuclear fuel built up by ceramic and graphitic layers, have outstanding high temperature resistance. TRISO fuel is the key technology for High Temperature Reactors (HTRs) and the Generation IV Very High Temperature Reactor (VHTR) variant. TRISO offers unparalleled containment of fission products and is extremely robust during accident conditions. An understanding of the thermal performance and mechanical properties of TRISO fuel requires a detailed knowledge of pore sizes, their distribution and interconnectivity. Here 50 nm, nano-, and 1 μm resolution, micro-computed tomography (CT), have been used to quantify non-destructively porosity of a surrogate TRISO particle at the 0.3–10 μm and 3–100 μm scales respectively. This indicates that pore distributions can reliably be measured down to a size approximately 3 times the pixel size which is consistent with the segmentation process. Direct comparison with Scanning Electron Microscopy (SEM) sections indicates that destructive sectioning can introduce significant levels of coarse damage, especially in the pyrolytic carbon layers. Further comparative work is required to identify means of minimizing such damage for SEM studies. Finally since it is non-destructive, multi-scale time-lapse X-ray CT opens the possibility of intermittently tracking the degradation of TRISO structure under thermal cycles or radiation conditions in order to validate models of degradation such as kernel movement. X-ray CT in-situ experimentation of TRISO particles under load and temperature could also be used to understand the internal changes that occur in the particles under accident conditions.

  6. Clinical multiphoton FLIM tomography

    Science.gov (United States)

    König, Karsten

    2012-03-01

    This paper gives an overview on current clinical high resolution multiphoton fluorescence lifetime imaging in volunteers and patients. Fluorescence lifetime imaging (FLIM) in Life Sciences was introduced in Jena/Germany in 1988/89 based on a ZEISS confocal picosecond dye laser scanning microscope equipped with a single photon counting unit. The porphyrin distribution in living cells and living tumor-bearing mice was studied with high spatial, temporal, and spectral resolution. Ten years later, time-gated cameras were employed to detect dental caries in volunteers based on one-photon excitation of autofluorescent bacteria with long fluorescence lifetimes. Nowadays, one-photon FLIM based on picosecond VIS laser diodes are used to study ocular diseases in humans. Already one decade ago, first clinical twophoton FLIM images in humans were taken with the certified clinical multiphoton femtosecond laser tomograph DermaInspectTM. Multiphoton tomographs with FLIM modules are now operating in hospitals at Brisbane, Tokyo, Berlin, Paris, London, Modena and other European cities. Multiple FLIM detectors allow spectral FLIM with a temporal resolution down to 20 ps (MCP) / 250 ps (PMT) and a spectral resolution of 10 nm. Major FLIM applications include the detection of intradermal sunscreen and tattoo nanoparticles, the detection of different melanin types, the early diagnosis of dermatitis and malignant melanoma, as well as the measurement of therapeutic effects in pateints suffering from dermatitis. So far, more than 1,000 patients and volunteers have been investigated with the clinical multiphoton FLIM tomographs DermaInspectTM and MPTflexTM.

  7. Tomography with energy dispersive diffraction

    Science.gov (United States)

    Stock, S. R.; Okasinski, J. S.; Woods, R.; Baldwin, J.; Madden, T.; Quaranta, O.; Rumaiz, A.; Kuczewski, T.; Mead, J.; Krings, T.; Siddons, P.; Miceli, A.; Almer, J. D.

    2017-09-01

    X-ray diffraction can be used as the signal for tomographic reconstruction and provides a cross-sectional map of the crystallographic phases and related quantities. Diffraction tomography has been developed over the last decade using monochromatic x-radiation and an area detector. This paper reports tomographic reconstruction with polychromatic radiation and an energy sensitive detector array. The energy dispersive diffraction (EDD) geometry, the instrumentation and the reconstruction process are described and related to the expected resolution. Results of EDD tomography are presented for two samples containing hydroxyapatite (hAp). The first is a 3D-printed sample with an elliptical crosssection and contains synthetic hAp. The second is a human second metacarpal bone from the Roman-era cemetery at Ancaster, UK and contains bio-hAp which may have been altered by diagenesis. Reconstructions with different diffraction peaks are compared. Prospects for future EDD tomography are also discussed.

  8. Computed tomography in renal trauma

    International Nuclear Information System (INIS)

    Brueck, W.; Eisenberger, F.; Buck, J.

    1981-01-01

    In a group of 19 patients suffering from flank trauma and gross hematuria the diagnostic value of angiography was compared with that of computed tomography. The cases that underwent both tests were found to have the some diagnosis of rupture of the kidney. Typical CT-findings in kidney rupture are demonstrated. Whereas angiography presents an exact picture of the arterial system of the kidney, including its injures computed tomography reveals the extent of organ lesons by showing extra- and intrarenal hematomas. If surgery is planned angiography is still mandatory, whereby the indication is largely determined by the clinical findings. Computed tomography as a non-invasive method is equally suitable for follow-ups. (orig.) [de

  9. Recent advances in neutron tomography

    International Nuclear Information System (INIS)

    McFarland, E.; Massachusetts Inst. of Technology, Cambridge, MA; Lanza, R.

    1993-01-01

    Neutron imaging has been shown to be an excellent imaging tool for many nondestructive evaluation applications. Significantly improved contrast over X-ray images is possible for materials commonly found in engineering assemblies. The major limitations have been the neutron source and detection. A low cost, position sensitive neutron tomography detector system has been designed and built based on an electro-optical detector system using a LiF-ZnS scintillator screen and a cooled charge coupled device. This detector system can be used for neutron radiography as well as two and three-dimensional neutron tomography. Calculated performance of the system predicted near-quantum efficiency for position sensitive neutron detection. Experimental data was recently taken using this system at McClellan Air Force Base, Air Logistics Center, Sacramento, CA. With increased availability of low cost neutron sources and advanced image processing, neutron tomography will become an increasingly important nondestructive imaging method

  10. Feasibility of speckle variance OCT for imaging cutaneous microvasculature regeneration during healing of wounds in diabetic mice

    Science.gov (United States)

    Sharma, P.; Kumawat, J.; Kumar, S.; Sahu, K.; Verma, Y.; Gupta, P. K.; Rao, K. D.

    2018-02-01

    We report on a study to assess the feasibility of a swept source-based speckle variance optical coherence tomography setup for monitoring cutaneous microvasculature. Punch wounds created in the ear pinnae of diabetic mice were monitored at different times post wounding to assess the structural and vascular changes. It was observed that the epithelium thickness increases post wounding and continues to be thick even after healing. Also, the wound size assessed by vascular images is larger than the physical wound size. The results show that the developed speckle variance optical coherence tomography system can be used to monitor vascular regeneration during wound healing in diabetic mice.

  11. Positron tomography. Methodology and applications

    International Nuclear Information System (INIS)

    Kellershohn, C.; Comar, D.

    1979-01-01

    Whereas single photon tomography provides a new and rewarding dimension to conventional nuclear medicine, positron tomography makes a new original approach possible of the analysis in vivo of fundamental biological and physiological processes. The main object of both is the sectional representation of the distribution of a radioactive indicator injected into the body system; compared with conventional detectors (gamma cameras and scintigraphic systems) they provide much greater accuracy in localization. The characteristics of these two methods can be presented schematically by comparing their respective advantages and drawbacks [fr

  12. Uncertainty analysis in seismic tomography

    Science.gov (United States)

    Owoc, Bartosz; Majdański, Mariusz

    2017-04-01

    Velocity field from seismic travel time tomography depends on several factors like regularization, inversion path, model parameterization etc. The result also strongly depends on an initial velocity model and precision of travel times picking. In this research we test dependence on starting model in layered tomography and compare it with effect of picking precision. Moreover, in our analysis for manual travel times picking the uncertainty distribution is asymmetric. This effect is shifting the results toward faster velocities. For calculation we are using JIVE3D travel time tomographic code. We used data from geo-engineering and industrial scale investigations, which were collected by our team from IG PAS.

  13. Positron emission tomography in oncology

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    This report describes the current and potential uses of positron emission tomography in clinical medicine and research related to oncology. Assessment will be possible of metabolism and physiology of tumors and their effects on adjacent tissues. Specific probes are likely to be developed for target sites on tumors, including monoclonal antibodies and specific growth factors that recognize tumors. To date, most oncological applications of positron emission tomography tracers have been qualitative; in the future, quantitative metabolic measurements should aid in the evaluation of tumor biology and response to treatment

  14. NMF on positron emission tomography

    DEFF Research Database (Denmark)

    Bödvarsson, Bjarni; Hansen, Lars Kai; Svarer, Claus

    2007-01-01

    In positron emission tomography, kinetic modelling of brain tracer uptake, metabolism or binding requires knowledge of the cerebral input function. Traditionally, this is achieved with arterial blood sampling in the arm or as shown in (Liptrot, M, et al., 2004) by non-invasive K-means clustering....... We propose another method to estimate time-activity curves (TAC) extracted directly from dynamic positron emission tomography (PET) scans by non-negative matrix factorization (NMF). Since the scaling of the basis curves is lost in the NMF the estimated TAC is scaled by a vector alpha which...

  15. Virtual electrical capacitance tomography sensor

    International Nuclear Information System (INIS)

    Li, Y; Yang, W Q

    2005-01-01

    Electrical capacitance tomography (ECT) is an effective technique for elucidating the distribution of dielectric materials inside closed pipes or vessels. This paper describes a virtual electrical capacitance tomography (VECT) system, which can simulate a range of sensor and hardware configurations and material distributions. A selection of popular image reconstruction algorithms has been made available and image error and capacitance error tools enable their performance to be evaluated and compared. Series of frame-by-frame results can be stored for simulating real-time dynamic flows. The system is programmed in Matlab with DOS functions. It is convenient to use and low-cost to operate, providing an effective tool for engineering experiment

  16. Cranial computed tomography in psychiatry

    International Nuclear Information System (INIS)

    Falkai, P.; Bogerts, B.

    1993-01-01

    Computed tomography has gained importance as a diagnostic tool in psychiatry to exclude structural brain pathology, but has passed on its role in research to magnetic resonance tomography. It helps to distinguish between senile dementia of Alzheimer type and multi-infarct dementia. The enlargement of the ventricular system and cortical sulci is well established in schizophrenic and affective psychosis. Some alcohol addicts show a considerable degree of cerebral atrophy, only exceeded by demented patients, but this condition is potentially reversible. To screen psychiatric patients by CT is recommendable, as 2-10% of hospitalized psychiatric patients have structural brain disease. (orig.) [de

  17. Positron emission tomography/computed tomography scanning for ...

    African Journals Online (AJOL)

    Background: Although the site of nosocomial sepsis in the critically ill ventilated patient is usually identifiable, it may remain occult, despite numerous investigations. The rapid results and precise anatomical location of the septic source using positron emission tomography (PET) scanning, in combination with computed ...

  18. Cardiac Computed Tomography (Multidetector CT, or MDCT)

    Science.gov (United States)

    ... Disease Venous Thromboembolism Aortic Aneurysm More Cardiac Computed Tomography (Multidetector CT, or MDCT) Updated:Sep 19,2016 What is Computerized Tomography (CT)? CT is a noninvasive test that uses ...

  19. The value of computed tomography in ''sciatica''

    International Nuclear Information System (INIS)

    Boehm-Jurkovic, H.; Hammer, B.

    1981-01-01

    13 cases of therapy-resistant lumboischialgia without herniated disk, caused in 12 cases by a tumour and in 1 case by an abscess, were examined by computed tomography of the lumbar and pelvic region. This method is indicated immediately after insufficient results of conventional X-ray methods (including tomography) and of lumbosacral radiculography. The computed tomography is indispensable also in patients with ''sciatica'' with a known malignoma. The information given by computed tomography is essential for the therapy planning. (author)

  20. Protean appearance of craniopharyngioma on computed tomography

    International Nuclear Information System (INIS)

    Danziger, A.; Price, H.I.

    1979-01-01

    Craniopharyngiomas present a diverse appearance on computed tomography. Histological diagnosis is not always possible, but computed tomography is of great assistance in the delineation of the tumour as well as of the degree of associated hydrocephalus. Computed tomography also enables rapid non-invasive follow-up after surgery or radiotherapy, or both