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Sample records for microcomputed tomography guided

  1. 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.

  2. Comparative study of chitosan/fibroin-hydroxyapatite and collagen membranes for guided bone regeneration in rat calvarial defects: micro-computed tomography analysis.

    Science.gov (United States)

    Song, Jae Min; Shin, Sang Hun; Kim, Yong Deok; Lee, Jae Yeol; Baek, Young Jae; Yoon, Sang Yong; Kim, Hong Sung

    2014-06-01

    This study aimed to utilize micro-computed tomography (micro-CT) analysis to compare new bone formation in rat calvarial defects using chitosan/fibroin-hydroxyapatite (CFB-HAP) or collagen (Bio-Gide) membranes. Fifty-four (54) rats were studied. A circular bony defect (8 mm diameter) was formed in the centre of the calvaria using a trephine bur. The CFB-HAP membrane was prepared by thermally induced phase separation. In the experimental group (n=18), the CFB-HAP membrane was used to cover the bony defect, and in the control group (n=18), a resorbable collagen membrane (Bio-Gide) was used. In the negative control group (n=18), no membrane was used. In each group, six animals were euthanized at 2, 4 and 8 weeks after surgery. The specimens were then analysed using micro-CT. There were significant differences in bone volume (BV) and bone mineral density (BMD) (Pmembrane groups. However, there were no significant differences between the CFB-HAP group and the collagen group. We concluded that the CFB-HAP membrane has significant potential as a guided bone regeneration (GBR) membrane.

  3. Microcomputers: Software Evaluation. Evaluation Guides. Guide Number 17.

    Science.gov (United States)

    Gray, Peter J.

    This guide discusses three critical steps in selecting microcomputer software and hardware: setting the context, software evaluation, and managing microcomputer use. Specific topics addressed include: (1) conducting an informal task analysis to determine how the potential user's time is spent; (2) identifying tasks amenable to computerization and…

  4. Microcomputers: Communication Software. Evaluation Guides. Guide Number 13.

    Science.gov (United States)

    Gray, Peter J.

    This guide discusses four types of microcomputer-based communication programs that could prove useful to evaluators: (1) the direct communication of information generated by one computer to another computer; (2) using the microcomputer as a terminal to a mainframe computer to input, direct the analysis of, and/or output data using a statistical…

  5. Comparative study of chitosan/fibroin–hydroxyapatite and collagen membranes for guided bone regeneration in rat calvarial defects: micro-computed tomography analysis

    OpenAIRE

    Song, Jae Min; Shin, Sang Hun; Kim, Yong Deok; Lee, Jae Yeol; Baek, Young Jae; Yoon, Sang Yong; Kim, Hong Sung

    2014-01-01

    This study aimed to utilize micro-computed tomography (micro-CT) analysis to compare new bone formation in rat calvarial defects using chitosan/fibroin–hydroxyapatite (CFB–HAP) or collagen (Bio-Gide) membranes. Fifty-four (54) rats were studied. A circular bony defect (8 mm diameter) was formed in the centre of the calvaria using a trephine bur. The CFB–HAP membrane was prepared by thermally induced phase separation. In the experimental group (n=18), the CFB–HAP membrane was used to cover the...

  6. Microcomputers and Evaluation. Evaluation Guides: Guide Number 1.

    Science.gov (United States)

    Gray, Peter J.

    The potential uses of microcomputers in evaluation research are discussed in this pamphlet. At the beginning, a matrix is provided showing the relationship between the steps in the evaluation research process and common types of computer software. Thereafter, the guide is organized sequentially around the evaluation research activities that are…

  7. Microcomputed tomography-based assessment of retrieved dental implants

    NARCIS (Netherlands)

    Narra, N.; Antalainen, A.K.; Zipprich, H.; Sándor, G.K.; Wolff, J.

    2015-01-01

    Purpose: The aim of this study was to demonstrate the potential of microcomputed tomography (micro-CT) technology in the assessment of retrieved dental implants. Cases are presented to illustrate the value of micro-CT imaging techniques in determining possible mechanical causes for dental implant

  8. Microcomputers: Statistical Analysis Software. Evaluation Guide Number 5.

    Science.gov (United States)

    Gray, Peter J.

    This guide discusses six sets of features to examine when purchasing a microcomputer-based statistics program: hardware requirements; data management; data processing; statistical procedures; printing; and documentation. While the current statistical packages have several negative features, they are cost saving and convenient for small to moderate…

  9. Micro-computed tomography for small animal imaging: Technological details

    Institute of Scientific and Technical Information of China (English)

    Hao Li; Hui Zhang; Zhiwei Tang; Guangshu Hu

    2008-01-01

    The high-resolution micro-computed tomography(micro-CT)system has now become an important tool for biological research.The micro-CT system enables a non-invasive inspection to screen anatomical changes in small animals.The promising advantages include high-spatial resolution,high sensitivity to bone and lung,short scan time and cost-effectiveness.The dose received by the small animal might be a critical concern in the research.In this article,the choice of the components,fundamental physical problems,the image reconstruction algorithm and the representative applications of micro-CT are summarized.Some results from our research group are also presented to show high-resolution images obtained by the micro-CT system.

  10. Microcomputers: Word Processing. Evaluation Guides. Guide Number 3.

    Science.gov (United States)

    Gray, Peter J.

    Designed to provide guidance in selecting the appropriate microcomputer-based word processing program, this document discusses the key characteristics of word processing software, including formatting, editing, merging, and printing. Possible capabilities of word processing features are identified, i.e., indent, tab, center, creation of footnotes,…

  11. X-Ray Micro-Computed Tomography Imaging of the Buzzard Coulee Chondrite

    Science.gov (United States)

    Melanson, D.; Samson, C.; Herd, R. K.; Fry, C.; McCausland, P. J. A.; Umoh, J.; Holdsworth, D. W.

    2012-03-01

    This abstract outlines research and some results of X-ray micro-computed tomography imaging of the Buzzard Coulee H4 chondrite. A comparison of bulk density results and an analysis of radio-density profile curves are discussed.

  12. Visualization of Three-Dimensional Nephron Structure With Microcomputed Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Bentley,M.; Jorgensen, S.; Lerman, L.; Ritman, E.; Romero, J.

    2007-01-01

    The three-dimensional architecture of nephrons in situ and their interrelationship with other nephrons are difficult to visualize by microscopic methods. The present study uses microcomputed X-ray tomography (micro-CT) to visualize intact nephrons in situ. Rat kidneys were perfusion-fixed with buffered formalin and their vasculature was subsequently perfused with radiopaque silicone. Cortical tissue was stained en bloc with osmium tetroxide, embedded in plastic, scanned, and reconstructed at voxel resolutions of 6, 2, and 1 {mu}m. At 6 {mu}m resolution, large blood vessels and glomeruli could be visualized but nephrons and their lumens were small and difficult to visualize. Optimal images were obtained using a synchrotron radiation source at 2 {mu}m resolution where nephron components could be identified, correlated with histological sections, and traced. Proximal tubules had large diameters and opaque walls, whereas distal tubules, connecting tubules, and collecting ducts had smaller diameters and less opaque walls. Blood vessels could be distinguished from nephrons by the luminal presence of radiopaque silicone. Proximal tubules were three times longer than distal tubules. Proximal and distal tubules were tightly coiled in the outer cortex but were loosely coiled in the middle and inner cortex. The connecting tubules had the narrowest diameters of the tubules and converged to form arcades that paralleled the radial vessels as they extended to the outer cortex. These results illustrate a potential use of micro-CT to obtain three-dimensional information about nephron architecture and nephron interrelationships, which could be useful in evaluating experimental tubular hypertrophy, atrophy, and necrosis.

  13. Visualization of three-dimensional nephron structure with microcomputed tomography.

    Science.gov (United States)

    Bentley, Michael D; Jorgensen, Steven M; Lerman, Lilach O; Ritman, Erik L; Romero, J Carlos

    2007-03-01

    The three-dimensional architecture of nephrons in situ and their interrelationship with other nephrons are difficult to visualize by microscopic methods. The present study uses microcomputed X-ray tomography (micro-CT) to visualize intact nephrons in situ. Rat kidneys were perfusion-fixed with buffered formalin and their vasculature was subsequently perfused with radiopaque silicone. Cortical tissue was stained en bloc with osmium tetroxide, embedded in plastic, scanned, and reconstructed at voxel resolutions of 6, 2, and 1 microm. At 6 microm resolution, large blood vessels and glomeruli could be visualized but nephrons and their lumens were small and difficult to visualize. Optimal images were obtained using a synchrotron radiation source at 2 microm resolution where nephron components could be identified, correlated with histological sections, and traced. Proximal tubules had large diameters and opaque walls, whereas distal tubules, connecting tubules, and collecting ducts had smaller diameters and less opaque walls. Blood vessels could be distinguished from nephrons by the luminal presence of radiopaque silicone. Proximal tubules were three times longer than distal tubules. Proximal and distal tubules were tightly coiled in the outer cortex but were loosely coiled in the middle and inner cortex. The connecting tubules had the narrowest diameters of the tubules and converged to form arcades that paralleled the radial vessels as they extended to the outer cortex. These results illustrate a potential use of micro-CT to obtain three-dimensional information about nephron architecture and nephron interrelationships, which could be useful in evaluating experimental tubular hypertrophy, atrophy, and necrosis.

  14. Microcomputed tomography and shock microdeformation studies on shatter cones

    Science.gov (United States)

    Zaag, Patrice Tristan; Reimold, Wolf Uwe; Hipsley, Christy Anna

    2016-08-01

    One of the aspects of impact cratering that are still not fully understood is the formation of shatter cones and related fracturing phenomena. Yet, shatter cones have been applied as an impact-diagnostic criterion for decades without the role of shock waves and target rock defects in their formation having been elucidated ever. We have tested the application of the nondestructive microcomputed tomography (μCT) method to visualize the interior of shatter cones in order to possibly resolve links between fracture patterns and shatter cone surface features (striations and intervening "valleys"). Shatter-coned samples from different impact sites and in different lithologies were investigated for their μCT suitability, with a shatter cone in sandstone from the Serra da Cangalha impact structure (Brazil) remaining as the most promising candidate because of the fracture resolution achieved. To validate the obtained CT data, the scanned specimen was cut into three orthogonal sets of thin sections. Scans with 13 μm resolution were obtained. μCT scans and microscopic analysis unraveled an orientation of subplanar fractures and related fluid inclusion trails, and planar fracture (PF) orientations in the interior of shatter cones. Planar deformation features (PDF) were observed predominantly near the shatter cone surface. Previously undescribed varieties of feather features (FF), in the form of lamellae emanating from curviplanar and curved fractures, as well as an "arrowhead"-like FF development with microlamellae originating from both sides of a PF, were observed. The timing of shatter cone formation was investigated by establishing temporal relations to the generation of various shock microscopic effects. Shatter cones are, thus, generated post- or syn-formation of PF, FF, subplanar fractures, and PDF. The earliest possible time for shatter cone formation is during the late stage of the compressional phase, that is, shock wave passage, of an impact event.

  15. Microcomputers: Instrument Generation Software. Evaluation Guides. Guide Number 11.

    Science.gov (United States)

    Gray, Peter J.

    Designed to assist evaluators in selecting the appropriate software for the generation of various data collection instruments, this guide discusses such key program characteristics as text entry, item storage and manipulation, item retrieval, and printing. Some characteristics of a good instrument generation program are discussed; these include…

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

    OpenAIRE

    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 w...

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

    Science.gov (United States)

    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.

  18. 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)

  19. Comparison of optical coherence tomography, microcomputed tomography, and histology at a three-dimensionally imaged trabecular bone sample

    Science.gov (United States)

    Kasseck, Christoph; Kratz, Marita; Torcasio, Antonia; Gerhardt, Nils C.; van Lenthe, G. Harry; Gambichler, Thilo; Hoffmann, Klaus; Jones, David B.; Hofmann, Martin R.

    2010-07-01

    We investigate optical coherence tomography (OCT) as a method for imaging bone. The OCT images are compared directly to those of the standard methods of bone histology and microcomputed tomography (μCT) on a single, fixed human femoral trabecular bone sample. An advantage of OCT over bone histology is its noninvasive nature. OCT also images the lamellar structure of trabeculae at slightly higher contrast than normal bone histology. While μCT visualizes the trabecular framework of the whole sample, OCT can image additionally cells with a penetration depth limited approximately to 1 mm. The most significant advantage of OCT, however, is the absence of toxic effects (no ionizing radiation), i.e., continuous images may be made and individual cell tracking may be performed. The penetration depth of OCT, however, limits its use to small animal models and small bone organ cultures.

  20. Micro-Computed Tomography and Finite Element Method Study of Open-Cell Porous Materials

    Directory of Open Access Journals (Sweden)

    Wejrzanowski Tomasz

    2015-01-01

    Full Text Available In the present paper the characterization of structure and properties of open-cell porous materials by high-resolution x-ray micro-computed tomography (μCT and finite element method (FEM is addressed. The unique properties of open porosity foams make them interesting in a range of applications in science and engineering such as energy absorbers, lightweight construction materials or heat insulators. Consequently, a detailed knowledge of structure as well as mechanical properties (i.e. Young’s Modulus, Poisson’s Ratio of such foams is essential. The resulting pixel size of the μCT was 40 μm, which enabled satisfactory visualization of the complex foam structure and quantitative characterization. Foam morphology was studied on post-processed computed tomography images, while mechanical properties were analyzed with use of the finite element method on numerical model obtained from μCT results.

  1. Virtual casting of stab wounds in cartilage using micro-computed tomography.

    Science.gov (United States)

    Pounder, Derrick J; Sim, Louise J

    2011-06-01

    In homicidal stabbings using a serrated knife, stab wounds involving costal cartilage leave striations on the cut surface of the cartilage from the serration points on the blade edge. Class characteristics of the serrated blade can be determined from the striation marks, and individualizing characteristics may be seen also. The traditional method for recording the striation marks involves the pernickety technique of casting with dental impression material. We assessed the potential utility of micro-computed tomography scanning of the stab track as a technique for nondestructive recording of striation patterns and virtual casting of them. Stab tracks in porcine cartilage, produced with a coarsely serrated blade, were scanned with a bench-top micro-computed tomography scanner. The typical irregularly regular striation pattern could be demonstrated, and the images manipulated, using proprietary software to produce a virtual cast. Whether the technology will have sufficient resolution to image not only class characteristic tool marks but also the much finer individualizing tool marks remains to be evaluated, but the technology shows considerable promise.

  2. Assessment of Root Canal Filling Removal Effectiveness Using Micro-computed Tomography: A Systematic Review.

    Science.gov (United States)

    Rossi-Fedele, Giampiero; Ahmed, Hany Mohamed Aly

    2017-04-01

    The removal of obturation materials from the root canal system is a primary objective in root canal retreatment procedures. This systematic review aims to discuss the effectiveness of different instrumentation procedures in removing root-canal filling materials assessed by micro-computed tomography. An electronic search in PubMed and major endodontic journals was conducted using appropriate key words to identify investigations that examined the effectiveness of obturation material removal assessed by micro-computed tomography. Among 345 studies, 22 satisfied the inclusion criteria. Seven studies compared hand instrumentation with Nickel-Titanium rotary or reciprocating systems. Three studies investigated rotary systems, and another three studies explored reciprocation. Eight studies compared rotary systems and reciprocation in removing filling materials from the root canal system. Other factors, such as the role of solvents and irrigant agitation, were discussed. The application of different instrumentation protocols can effectively, but not completely, remove the filling materials from the root canal system. Only hand instrumentation was not associated with iatrogenic errors. Reciprocating and rotary systems exhibited similar abilities in removing root filling material. Retreatment files performed similarly to conventional ones. Solvents enhanced penetration of files but hindered cleaning of the root canal. The role of irrigant agitation was determined as controversial. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  3. 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...

  4. 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.

  5. 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.

  6. Mapping the calcification of bovine pericardium in rat model by enhanced micro-computed tomography.

    Science.gov (United States)

    Liu, Jing; Zhong, Shengping; Lan, Hualin; Meng, Xu; Zhang, Haibo; Fan, Yubo; Wang, Yuxing; Wang, Chunren; Wang, Zhaoxu

    2014-09-01

    The calcification initiation and progression of bioprosthetic heart valve were investigated in a rat model by enhanced micro-computed tomography, together with histologic study and scanning electron microscope analysis. The implantation data at early stage showed apparent dendritic patterns in the radiographic images for the glutaraldehyde-treated bovine pericardium and this dendritic pattern was verified to be associated with the vessel distribution in the tissue. Histologic study and scanning electron microscope analysis both indicated that the calcium deposits in the pericardium vessels regions were more grievous than those scattered in the collagen fibers in the first two weeks after implantation. Subsequently, calcification spreaded and the entire sample was severely calcified in 60 days. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Guided Wave Travel Time Tomography for Bends

    NARCIS (Netherlands)

    Volker, A.W.F.; Zon, A.T. van

    2012-01-01

    The concept of predictive maintenance using permanent sensors that monitor the integrity of an installation is an interesting addition to the current method of periodic inspections. Guided wave tomography has been developed to map the wall thickness using the travel times of guided waves. The method

  8. Guided wave travel time tomography for bends

    NARCIS (Netherlands)

    Volker, A.W.F.; Bloom, J.G.P.

    2010-01-01

    The concept of predictive maintenance using permanent sensors that monitor the integrity of an installation is an interesting addition to the current method of periodic inspections. Guided wave tomography has been developed to map the wall thickness using the travel times of guided waves. The method

  9. Nondestructive observation of teeth post core-space using optical coherence tomography: comparison with microcomputed tomography and live images

    Science.gov (United States)

    Minamino, Takuya; Mine, Atsushi; Matsumoto, Mariko; Sugawa, Yoshihiko; Kabetani, Tomoshige; Higashi, Mami; Kawaguchi, Asuka; Ohmi, Masato; Awazu, Kunio; Yatani, Hirofumi

    2015-10-01

    No previous reports have observed inside the root canal using both optical coherence tomography (OCT) and x-ray microcomputed tomography (μCT) for the same sample. The purpose of this study was to clarify both OCT and μCT image properties from observations of the same root canal after resin core build-up treatment. As OCT allows real-time observation of samples, gap formation may be able to be shown in real time. A dual-cure, one-step, self-etch adhesive system bonding agent, and dual-cure resin composite core material were used in root canals in accordance with instructions from the manufacturer. The resulting OCT images were superior for identifying gap formation at the interface, while μCT images were better to grasp the tooth form. Continuous tomographic images from real-time OCT observation allowed successful construction of a video of the resin core build-up procedure. After 10 to 12 s of light curing, a gap with a clear new signal occurred at the root-core material interface, proceeding from the coronal side (6 mm from the cemento-enamel junction) to the apical side of the root.

  10. Micro-computed tomography: Introducing new dimensions to taxonomy.

    Science.gov (United States)

    Faulwetter, Sarah; Vasileiadou, Aikaterini; Kouratoras, Michail; Thanos Dailianis; Arvanitidis, Christos

    2013-01-01

    Continuous improvements in the resolution of three-dimensional imaging have led to an increased application of these techniques in conventional taxonomic research in recent years. Coupled with an ever increasing research effort in cybertaxonomy, three-dimensional imaging could give a boost to the development of virtual specimen collections, allowing rapid and simultaneous access to accurate virtual representations of type material. This paper explores the potential of micro-computed tomography (X-ray micro-tomography), a non-destructive three-dimensional imaging technique based on mapping X-ray attenuation in the scanned object, for supporting research in systematics and taxonomy. The subsequent use of these data as virtual type material, so-called "cybertypes", and the creation of virtual collections lie at the core of this potential. Sample preparation, image acquisition, data processing and presentation of results are demonstrated using polychaetes (bristle worms), a representative taxon of macro-invertebrates, as a study object. Effects of the technique on the morphological, anatomical and molecular identity of the specimens are investigated. The paper evaluates the results and discusses the potential and the limitations of the technique for creating cybertypes. It also discusses the challenges that the community might face to establish virtual collections. Potential future applications of three-dimensional information in taxonomic research are outlined, including an outlook to new ways of producing, disseminating and publishing taxonomic information.

  11. Quantification and characterization of radiation-induced changes to mandibular vascularity using micro-computed tomography.

    Science.gov (United States)

    Deshpande, Sagar Satish; Donneys, Alexis; Farberg, Aaron Samuel; Tchanque-Fossuo, Catherine N; Felice, Peter A; Buchman, Steven Richard

    2014-01-01

    Perhaps the most vexing and exigent problem confronting head and neck cancer reconstruction is overcoming the impediments of collateral damage imposed by radiation therapy (XRT) on normal surrounding tissue. Radiation therapy is detrimental to bone and soft tissue repair resulting in an unacceptably high incidence of devastating wound healing complications as well as the associated morbidity of late pathologic fractures, reduced bone healing, and osteoradionecrosis. The consequences of XRT on bone vasculature, long known to be affected by radiation, have been poorly understood. The purpose of this study was to analyze the degree by which irradiation degrades existing bone vascularity using a powerful micro-computed tomography technique to attain highly precise quantitative metrics of the vascular tree. Fourteen 400-g male Sprague-Dawley rats underwent 35 Gy of fractionated XRT at 7 Gy/d. The animals were euthanized after 28 days, and the left ventricle was fixed and injected with Microfil (MV-122; Flow Tech, Carver, Mass) contrast. Left hemimandibles were dissected and scanned using high-resolution micro-computed tomography (18-μm voxels). The vessel number, thickness, separation, connectivity, and vessel volume fraction were analyzed for the region of interest, defined to be the volume behind the third molar spanning a total distance of 5.1 mm. Stereologic analysis and subsequent analysis of variance test demonstrated a significant and quantifiable diminution in the irradiated vasculature when compared with control animals. The vessel volume fraction (0.016 vs 0.032, P ≤ 0.003) and vessel thickness (0.042 vs 0.067 mm, P ≤ 0.001) were markedly reduced. Interestingly, further analysis demonstrated no significant differences between vessel separation and vessel number. The results of our study specifically quantify the corrosive affects of XRT on the vasculature of the mandible. The data from this novel technique go even further and imply retention of blood

  12. Micro-computed tomography image-based evaluation of 3D anisotropy degree of polymer scaffolds.

    Science.gov (United States)

    Pérez-Ramírez, Ursula; López-Orive, Jesús Javier; Arana, Estanislao; Salmerón-Sánchez, Manuel; Moratal, David

    2015-01-01

    Anisotropy is one of the most meaningful determinants of biomechanical behaviour. This study employs micro-computed tomography (μCT) and image techniques for analysing the anisotropy of regenerative medicine polymer scaffolds. For this purpose, three three-dimensional anisotropy evaluation image methods were used: ellipsoid of inertia (EI), mean intercept length (MIL) and tensor scale (t-scale). These were applied to three patterns (a sphere, a cube and a right prism) and to two polymer scaffold topologies (cylindrical orthogonal pore mesh and spherical pores). For the patterns, the three methods provided good results. Regarding the scaffolds, EI mistook both topologies (0.0158, [-0.5683; 0.6001]; mean difference and 95% confidence interval), and MIL showed no significant differences (0.3509, [0.0656; 0.6362]). T-scale is the preferable method because it gave the best capability (0.3441, [0.1779; 0.5102]) to differentiate both topologies. This methodology results in the development of non-destructive tools to engineer biomimetic scaffolds, incorporating anisotropy as a fundamental property to be mimicked from the original tissue and permitting its assessment by means of μCT image analysis.

  13. Micro-computed tomography of false starts produced on bone by different hand-saws.

    Science.gov (United States)

    Pelletti, Guido; Viel, Guido; Fais, Paolo; Viero, Alessia; Visentin, Sindi; Miotto, Diego; Montisci, Massimo; Cecchetto, Giovanni; Giraudo, Chiara

    2017-05-01

    The analysis of macro- and microscopic characteristics of saw marks on bones can provide useful information about the class of the tool utilized to produce the injury. The aim of the present study was to test micro-computed tomography (micro-CT) for the analysis of false starts experimentally produced on 32 human bone sections using 4 different hand-saws in order to verify the potential utility of micro-CT for distinguishing false starts produced by different saws and to correlate the morphology of the tool with that of the bone mark. Each sample was analysed through stereomicroscopy and micro-CT. Stereomicroscopic analysis allowed the identification of the false starts and the detection of the number of tool marks left by each saw. Micro-CT scans, through the integration of 3D renders and multiplanar reconstructions (MPR), allowed the identification of the shape of each false start correlating it to the injuring tool. Our results suggest that micro-CT could be a useful technique for assessing false starts produced by different classes of saws, providing accurate morphological profiles of the bone marks with all the advantages of high resolution 3D imaging (e.g., high accuracy, non-destructive analysis, preservation and documentation of evidence). However, further studies are necessary to integrate qualitative data with quantitative metrical analysis in order to further characterize the false start and the related injuring tool. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Three-dimensional microstructure of human alveolar trabecular bone: a micro-computed tomography study

    Science.gov (United States)

    2017-01-01

    Purpose The microstructural characteristics of trabecular bone were identified using micro-computed tomography (micro-CT), in order to develop a potential strategy for implant surface improvement to facilitate osseointegration. Methods Alveolar bone specimens from the cadavers of 30 humans were scanned by high-resolution micro-CT and reconstructed. Volumes of interest chosen within the jaw were classified according to Hounsfield units into 4 bone quality categories. Several structural parameters were measured and statistically analyzed. Results Alveolar bone specimens with D1 bone quality had significantly higher values for all structural parameters than the other bone quality categories, except for trabecular thickness (Tb.Th). The percentage of bone volume, trabecular separation (Tb.Sp), and trabecular number (Tb.N) varied significantly among bone quality categories. Tb.Sp varied markedly across the bone quality categories (D1: 0.59±0.22 mm, D4: 1.20±0.48 mm), whereas Tb.Th had similar values (D1: 0.30±0.08 mm, D4: 0.22±0.05 mm). Conclusions Bone quality depended on Tb.Sp and number—that is, endosteal space architecture—rather than bone surface and Tb.Th. Regardless of bone quality, Tb.Th showed little variation. These factors should be taken into account when developing individualized implant surface topographies. PMID:28261521

  15. The use of microcomputed tomography to study microvasculature in small rodents.

    Science.gov (United States)

    Bentley, Michael D; Ortiz, Maria C; Ritman, Erik L; Romero, J Carlos

    2002-05-01

    Appropriate nephron function is dependent on the intrarenal arrangement of blood vessels. The preferred and primary means to study the architecture of intrarenal circulation has been by filling it with opaque substances such as india ink, radio-opaque contrast material, or various polymers for study by light or scanning electron microscopy. With such methodologies, superficial vessels may obscure deep vessels and little quantitative information may be obtained. Serial-section microtomy has not been practical because of problems relating to alignment and registration of adjacent sections, lost sections, and preparation time and effort. Microcomputed tomography (micro-CT) overcomes such limitations and provides a means to study the three-dimensional architecture of filled vessels within an intact rodent kidney and to obtain more quantitative information. As an example of micro-CT's capabilities, we review the use of micro-CT to study the alterations in renal microvasculature caused by the development of liver cirrhosis after chronic bile duct ligation. In this example, micro-CT evidence shows a selective decrease in cortical vascular filling in the kidney, with a maintenance of medullary vascular filling. These changes may contribute to the salt and water retention that accompanies cirrhosis. These results indicate that micro-CT is a promising method to evaluate renal vascular architecture in the intact rodent kidney relative to physiological and pathological function.

  16. Shrinkage assessment of low shrinkage composites using micro-computed tomography.

    Science.gov (United States)

    Hirata, Ronaldo; Clozza, Emanuele; Giannini, Marcelo; Farrokhmanesh, Ehsan; Janal, Malvin; Tovar, Nick; Bonfante, Estevam A; Coelho, Paulo G

    2015-05-01

    The aim of this study was to quantify the polymerization volumetric shrinkage of one regular and two low shrinkage bulk fill composites in class I cavities with or without an adhesive layer, using three-dimensional (3D) micro-computed tomography (μCT). Class I cavity preparations (2.5 mm depth × 4 mm length × 4 mm wide) were standardized in 36 extracted human third molars, which were randomly divided in six groups (n = 6 each) as follows: Group VIT (regular composite without bonding agent); Group SDR (low shrinkage flowable composite without bonding agent); Group TET (low shrinkage composite without bonding agent); Group VIT/P (regular composite with bonding agent); Group SDR/X (low shrinkage flowable composite with bonding agent); TET/T (low shrinkage composite with bonding agent). Each tooth was scanned via µCT at cavity preparation, immediately after cavity filling, and after light-curing. Acquired μCT data were imported into Amira software for analysis and volume values evaluated between steps from cavity preparation until light-curing. Both low shrinkage composites showed a significantly less volumetric shrinkage than VIT. The use of dental adhesive significantly decreased the average volumetric contraction similarly for the three composites, by about 20%. Both low shrinkage composites showed less volumetric polymerization contraction than the regular composite. The use of dental adhesive decreased the total volumetric shrinkage for all evaluated composites. © 2014 Wiley Periodicals, Inc.

  17. Measurement of kidney stone formation in the rat model using micro-computed tomography

    Science.gov (United States)

    Umoh, Joseph U.; Pitelka, Vasek; Goldberg, Harvey A.; Holdsworth, David W.

    2012-03-01

    Kidney stones were induced in 5 rats by treating them with 1% ethylene glycol and 1% ammonium chloride through free drinking water for six weeks. The animals were anesthetized and imaged in vivo before the treatment at week 0, to obtain baseline data, then at weeks 2 and 6 to monitor the kidney stone formation. Micro-CT imaging was performed with x-ray tube voltage of 90 kV and a current of 40 mA. At week 2, kidney stone formation was observed. A micro-computed tomography methodology of estimating the volume and hydroxyapatite-equivalent mineral content of the kidney stone is presented. It determines the threshold CT number (390 HU) that separates the kidney stone from the tissue. The mean volume of the stones in the 10 kidneys significantly increased from 3.81+/-0.72 mm3 at week 2 to 23.96+/-9.12 mm3 at week 6 (perror was about 4%. This method allows analysis of the kidney stone formation to be carried out in vivo, with fewer experimental animals compared with other ex vivo methods, in which animals are sacrificed. It is precise, accurate, non-destructive, and could be used in pre-clinical research to study the formation of kidney stones in live small animals.

  18. Evaluation of Angiogenesis Using Micro-Computed Tomography in a Xenograft Mouse Model of Lung Cancer

    Directory of Open Access Journals (Sweden)

    Rajkumar Savai

    2009-01-01

    Full Text Available Quantitative evaluation of lung tumor angiogenesis using immunohistochemical techniques has been limited by difficulties in generating reproducible data. To analyze intrapulmonary tumor angiogenesis, we used high-resolution micro-computed tomography (micro-CT of lung tumors of mice inoculated with mouse Lewis lung carcinoma (LLC1 or human adenocarcinoma (A549 cell lines. The lung vasculature was filled with the radiopaque silicone rubber, Microfil, through the jugular vein (in vivo application or pulmonary artery (ex vivo application. In addition, human adenocarcinoma lung tumor-bearing mice treated site-specifically with humanized monoclonal antibody (bevacizumab against vascular endothelial growth factor. Quantitative analysis of lung tumor microvessels imaged with micro-CT showed that more vessels (mainly small, <0.02 mm2 were filled using the in vivo (5.4% compared with the ex vivo (2.1% method. Furthermore, bevacizumab-treated lung tumor-bearing mice showed significantly reduced lung tumor volume and lung tumor angiogenesis compared with untreated mice as assessed by micro-CT. Interestingly, microvascularization of mainly the smaller vessels (<0.02 mm2 was reduced after bevacizumab treatment. This observation with micro-CT was nicely correlated with immunohistochemical measurement of microvessels. Therefore, micro-CT is a novel method for investigating lung tumor angiogenesis, and this might be considered as an additional complementary tool for precise quantification of angiogenesis.

  19. Microcomputed Tomography Evaluation of Polymerization Shrinkage of Class I Flowable Resin Composite Restorations.

    Science.gov (United States)

    Sampaio, C S; Chiu, K-J; Farrokhmanesh, E; Janal, M; Puppin-Rontani, R M; Giannini, M; Bonfante, E A; Coelho, P G; Hirata, R

    The present study aimed to characterize the pattern and volume of polymerization shrinkage of flowable resin composites, including one conventional, two bulk fill, and one self-adhesive. Standardized class I preparations (2.5 mm depth × 4 mm length × 4 mm wide) were performed in 24 caries-free human third molars that were randomly divided in four groups, according to the resin composite and adhesive system used: group 1 = Permaflo + Peak Universal Bond (PP); group 2 = Filtek Bulk Fill + Scotchbond Universal (FS); group 3 = Surefil SDR + XP Bond (SX); and group 4 = Vertise flow self-adhering (VE) (n=6). Each tooth was scanned three times using a microcomputed tomography (μCT) apparatus. The first scan was done after the cavity preparation, the second after cavity filling with the flowable resin composite before curing, and the third after it was cured. The μCT images were imported into three-dimensional rendering software, and volumetric polymerization shrinkage percentage was calculated for each sample. Data were submitted to one-way analysis of variance and post hoc comparisons. No significant difference was observed among PP, FS, and VE. SX bulk fill resin composite presented the lowest values of volumetric shrinkage. Shrinkage was mostly observed along the occlusal surface and part of the pulpal floor. In conclusion, polymerization shrinkage outcomes in a 2.5-mm deep class I cavity were material dependent, although most materials did not differ. The location of shrinkage was mainly at the occlusal surface.

  20. Effects of Articular Cartilage Constituents on Phosphotungstic Acid Enhanced Micro-Computed Tomography

    Science.gov (United States)

    Karhula, Sakari S.; Finnilä, Mikko A.; Lammi, Mikko J.; Ylärinne, Janne H.; Kauppinen, Sami; Rieppo, Lassi; Pritzker, Kenneth P. H.; Nieminen, Heikki J.; Saarakkala, Simo

    2017-01-01

    Contrast-enhanced micro-computed tomography (CEμCT) with phosphotungstic acid (PTA) has shown potential for detecting collagen distribution of articular cartilage. However, the selectivity of the PTA staining to articular cartilage constituents remains to be elucidated. The aim of this study was to investigate the dependence of PTA for the collagen content in bovine articular cartilage. Adjacent bovine articular cartilage samples were treated with chondroitinase ABC and collagenase to degrade the proteoglycan and the collagen constituents in articular cartilage, respectively. Enzymatically degraded samples were compared to the untreated samples using CEμCT and reference methods, such as Fourier-transform infrared imaging. Decrease in the X-ray attenuation of PTA in articular cartilage and collagen content was observed in cartilage depth of 0–13% and deeper in tissue after collagen degradation. Increase in the X-ray attenuation of PTA was observed in the cartilage depth of 13–39% after proteoglycan degradation. The X-ray attenuation of PTA-labelled articular cartilage in CEμCT is associated mainly with collagen content but the proteoglycans have a minor effect on the X-ray attenuation of the PTA-labelled articular cartilage. In conclusion, the PTA labeling provides a feasible CEμCT method for 3D characterization of articular cartilage. PMID:28135331

  1. Quantification of arthritic bone degradation by analysis of 3D micro-computed tomography data

    Science.gov (United States)

    Svensson, Carl-Magnus; Hoffmann, Bianca; Irmler, Ingo M.; Straßburger, Maria; Figge, Marc Thilo; Saluz, Hans Peter

    2017-01-01

    The use of animal models of arthritis is a key component in the evaluation of therapeutic strategies against the human disease rheumatoid arthritis (RA). Here we present quantitative measurements of bone degradation characterised by the cortical bone profile using glucose-6-phosphate isomerase (G6PI) induced arthritis. We applied micro-computed tomography (μCT) during three arthritis experiments and one control experiment to image the metatarsals of the hind paws and to investigate the effect of experimental arthritis on their cortical bone profile. For measurements of the cortical profile we automatically identified slices that are orthogonal to individual metatarsals, thereby making the measurements independent of animal placement in the scanner. We measured the average cortical thickness index (CTI) of the metatarsals, as well as the thickness changes along the metatarsal. In this study we introduced the cortical thickness gradient (CTG) as a new measure and we investigated how arthritis affects this measure. We found that in general both CTI and CTG are able to quantify arthritic progression, whilst CTG was found to be the more sensitive measure. PMID:28290525

  2. 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.

  3. Three dimensional distribution of surfactant in microspheres revealed by synchrotron radiation X-ray microcomputed tomography

    Directory of Open Access Journals (Sweden)

    Li Wu

    2017-07-01

    Full Text Available This study investigated the formulation mechanism of microspheres via internal surfactant distribution. Eudragit L100 based microspheres loaded with bovine serum albumin were prepared by solid in oil in oil emulsion solvent evaporation method using acetone and liquid paraffin system containing sucrose stearate as a surfactant. The fabricated microspheres were evaluated for encapsulation efficiency, particle size, production yield, and in vitro release characteristics. The internal structures of microspheres were characterized using synchrotron radiation X-ray microcomputed tomography (SR-µCT. The enhanced contrast made the sucrose stearate distinguished from Eudragit to have its three dimensional (3D distribution. Results indicated that the content and concentration determined the state of sucrose stearate and had significant influences on the release kinetics of protein. The dispersity of sucrose stearate was the primary factor that controlled the structure of the microspheres and further affected the encapsulation efficiency, effective drug loading, as well as in vitro release behavior. In conclusion, the 3D internal distribution of surfactant in microspheres and its effects on protein release behaviors have been revealed for the first time. The highly resolved 3D architecture provides new evidence for the deep understanding of the microsphere formation mechanism.

  4. Noninvasive technique for monitoring drug transport through the murine cochlea using micro-computed tomography.

    Science.gov (United States)

    Haghpanahi, Masoumeh; Gladstone, Miriam B; Zhu, Xiaoxia; Frisina, Robert D; Borkholder, David A

    2013-10-01

    Local delivery of drugs to the inner ear has the potential to treat inner ear disorders including permanent hearing loss or deafness. Current mathematical models describing the pharmacokinetics of drug delivery to the inner ear have been based on large rodent studies with invasive measurements of concentration at few locations within the cochlea. Hence, estimates of clearance and diffusion parameters are based on fitting measured data with limited spatial resolution to a model. To overcome these limitations, we developed a noninvasive imaging technique to monitor and characterize drug delivery inside the mouse cochlea using micro-computed tomography (μCT). To increase the measurement accuracy, we performed a subject-atlas image registration to exploit the information readily available in the atlas image of the mouse cochlea and pass segmentation or labeling information from the atlas to our μCT scans. The approach presented here has the potential to quantify concentrations at any point along fluid-filled scalae of the inner ear. This may permit determination of spatially dependent diffusion and clearance parameters for enhanced models.

  5. Magnetic resonance imaging and micro-computed tomography combined atlas of developing and adult mouse brains for stereotaxic surgery.

    Science.gov (United States)

    Aggarwal, M; Zhang, J; Miller, M I; Sidman, R L; Mori, S

    2009-09-15

    Stereotaxic atlases of the mouse brain are important in neuroscience research for targeting of specific internal brain structures during surgical operations. The effectiveness of stereotaxic surgery depends on accurate mapping of the brain structures relative to landmarks on the skull. During postnatal development in the mouse, rapid growth-related changes in the brain occur concurrently with growth of bony plates at the cranial sutures, therefore adult mouse brain atlases cannot be used to precisely guide stereotaxis in developing brains. In this study, three-dimensional stereotaxic atlases of C57BL/6J mouse brains at six postnatal developmental stages: postnatal day (P) 7, P14, P21, P28, P63 and in adults (P140-P160) were developed, using diffusion tensor imaging (DTI) and micro-computed tomography (CT). At present, most widely-used stereotaxic atlases of the mouse brain are based on histology, but the anatomical fidelity of ex vivo atlases to in vivo mouse brains has not been evaluated previously. To account for ex vivo tissue distortion due to fixation as well as individual variability in the brain, we developed a population-averaged in vivo magnetic resonance imaging adult mouse brain stereotaxic atlas, and a distortion-corrected DTI atlas was generated by nonlinearly warping ex vivo data to the population-averaged in vivo atlas. These atlas resources were developed and made available through a new software user-interface with the objective of improving the accuracy of targeting brain structures during stereotaxic surgery in developing and adult C57BL/6J mouse brains.

  6. Magnetic Resonance Imaging and Micro-Computed Tomography Combined Atlas of Developing and Adult Mouse Brains for Stereotaxic Surgery

    Science.gov (United States)

    Aggarwal, Manisha; Zhang, Jiangyang; Miller, Michael I.; Sidman, Richard L.; Mori, Susumu

    2009-01-01

    Stereotaxic atlases of the mouse brain are important in neuroscience research for targeting of specific internal brain structures during surgical operations. The effectiveness of stereotaxic surgery depends on accurate mapping of the brain structures relative to landmarks on the skull. During postnatal development in the mouse, rapid growth-related changes in the brain occur concurrently with growth of bony plates at the cranial sutures, therefore adult mouse brain atlases cannot be used to precisely guide stereotaxis in developing brains. In this study, three-dimensional stereotaxic atlases of C57BL/6J mouse brains at six postnatal developmental stages: P7, P14, P21, P28, P63 and in adults (P140–P160) were developed, using diffusion tensor imaging (DTI) and micro-computed tomography (CT). At present, most widely-used stereotaxic atlases of the mouse brain are based on histology, but the anatomical fidelity of ex vivo atlases to in vivo mouse brains has not been evaluated previously. To account for ex vivo tissue distortion due to fixation as well as individual variability in the brain, we developed a population-averaged in vivo MRI adult mouse brain stereotaxic atlas, and a distortion-corrected DTI atlas was generated by nonlinearly warping ex vivo data to the population-averaged in vivo atlas. These atlas resources were developed and made available through a new software user-interface with the objective of improving the accuracy of targeting brain structures during stereotaxic surgery in developing and adult C57BL/6J mouse brains. PMID:19490934

  7. Long-term macrobioerosion in the Mediterranean Sea assessed by micro-computed tomography

    Science.gov (United States)

    Färber, Claudia; Titschack, Jürgen; Schönberg, Christine Hanna Lydia; Ehrig, Karsten; Boos, Karin; Baum, Daniel; Illerhaus, Bernhard; Asgaard, Ulla; Granville Bromley, Richard; Freiwald, André; Wisshak, Max

    2016-06-01

    Biological erosion is a key process for the recycling of carbonate and the formation of calcareous sediments in the oceans. Experimental studies showed that bioerosion is subject to distinct temporal variability, but previous long-term studies were restricted to tropical waters. Here, we present results from a 14-year bioerosion experiment that was carried out along the rocky limestone coast of the island of Rhodes, Greece, in the Eastern Mediterranean Sea, in order to monitor the pace at which bioerosion affects carbonate substrate and the sequence of colonisation by bioeroding organisms. Internal macrobioerosion was visualised and quantified by micro-computed tomography and computer-algorithm-based segmentation procedures. Analysis of internal macrobioerosion traces revealed a dominance of bioeroding sponges producing eight types of characteristic Entobia cavity networks, which were matched to five different clionaid sponges by spicule identification in extracted tissue. The morphology of the entobians strongly varied depending on the species of the producing sponge, its ontogenetic stage, available space, and competition by other bioeroders. An early community developed during the first 5 years of exposure with initially very low macrobioerosion rates and was followed by an intermediate stage when sponges formed large and more diverse entobians and bioerosion rates increased. After 14 years, 30 % of the block volumes were occupied by boring sponges, yielding maximum bioerosion rates of 900 g m-2 yr-1. A high spatial variability in macrobioerosion prohibited clear conclusions about the onset of macrobioerosion equilibrium conditions. This highlights the necessity of even longer experimental exposures and higher replication at various factor levels in order to better understand and quantify temporal patterns of macrobioerosion in marine carbonate environments.

  8. 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.

  9. Stenotic Bicuspid and Tricuspid Aortic Valves - Micro-Computed Tomography and Biological Indices of Calcification.

    Science.gov (United States)

    Mazur, Piotr; Wypasek, Ewa; Gawęda, Bogusław; Sobczyk, Dorota; Kapusta, Przemysław; Natorska, Joanna; Malinowski, Krzysztof Piotr; Tarasiuk, Jacek; Bochenek, Maciej; Wroński, Sebastian; Chmielewska, Katarzyna; Kapelak, Bogusław; Undas, Anetta

    2017-06-23

    Valve calcification is well estimated by ex-vivo micro-computed tomography (micro-CT). The objective of this study was to investigate the associations between micro-CT findings and biological indices of calcification in aortic stenosis (AS), as well as differences between bicuspid aortic valve (BAV) and tricuspid aortic valve (TAV).Methods and Results:Aortic valves and plasma were obtained from patients undergoing valve surgery. Valves were dissected and underwent micro-CT, genetic analyses, and calcium content assessment. Plasma levels of calcification markers were measured. Forty-two patients with isolated severe AS, including 22 with BAV, were studied. BAV patients had a lower median CT value (140.0 [130.0-152.0] vs. 157.0 [147.0-176.0], P=0.002) and high-density calcification (HDC) fraction (9.3 [5.7-23.3] % vs. 21.3 [14.3-31.2] %, P=0.01), as compared with TAV. Calcification fraction (CF) correlated with AS severity (measured as maximal transvalvular pressure gradient [r=0.34, P=0.03], maximal flow velocity [r=0.38, P=0.02], and indexed aortic valve area [r=-0.37, P=0.02]). For TAV patients only, mRNA expression of integrin-binding sialoprotein correlated with CF (r=0.45, P=0.048), and the receptor activator of the nuclear factor κ-B ligand transcript correlated with HDC corrugation (r=0.54, P=0.01). TAV patients with AS present more mineralized calcifications in micro-CT than BAV subjects. The relative volume of calcifications increases with the AS severity. In TAV patients, upregulated expression of genes involved in osteoblastogenesis in AS correlates with leaflet mineralization in micro-CT.

  10. 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.

  11. Investigation of spatial resolution characteristics of an in vivo microcomputed tomography system

    Energy Technology Data Exchange (ETDEWEB)

    Ghani, Muhammad U. [Center for Biomedical engineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, OK 73019 (United States); Zhou, Zhongxing [Center for Biomedical engineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, OK 73019 (United States); School of Precision and Optoelectronics Engineering, Tianjin University, Tianjin 300072 (China); Ren, Liqiang; Wong, Molly; Li, Yuhua; Zheng, Bin [Center for Biomedical engineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, OK 73019 (United States); Yang, Kai [Department of Radiology, Massachusetts General Hospital, 55 Fruit Street, Boston, MA 02114 (United States); Liu, Hong, E-mail: liu@ou.edu [Center for Biomedical engineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, OK 73019 (United States)

    2016-01-21

    The spatial resolution characteristics of an in vivo microcomputed tomography (CT) system was investigated in the in-plane (x–y), cross plane (z) and projection imaging modes. The microCT system utilized in this study employs a flat panel detector with a 127 µm pixel pitch, a microfocus x-ray tube with a focal spot size ranging from 5–30 µm, and accommodates three geometric magnifications (M) of 1.72, 2.54 and 5.10. The in-plane modulation transfer function (MTF) curves were measured as a function of the number of projections, geometric magnification (M), detector binning and reconstruction magnification (M{sub Recon}). The in plane cutoff frequency (10% MTF) ranged from 2.31 lp/mm (M=1.72, 2×2 binning) to 12.56 lp/mm (M=5.10, 1×1 binning) and a bar pattern phantom validated those measurements. A slight degradation in the spatial resolution was observed when comparing the image reconstruction with 511 and 918 projections, whose effect was visible at the lower frequencies. Small value of M{sub Recon} has little or no impact on the in-plane spatial resolution owning to a stable system. Large value of M{sub Recon} has implications on the spatial resolution and it was evident when comparing the bar pattern images reconstructed with M{sub Recon}=1.25 and 2.5. The cross plane MTF curves showed that the spatial resolution increased as the slice thickness decreased. The cutoff frequencies in the projection imaging mode yielded slightly higher values as compared to the in-plane and cross plane modes at all the geometric magnifications (M). At M=5.10, the cutoff resolution of the projection and cross plane on an ultra-high contrast resolution bar chip phantom were 14.9 lp/mm and 13–13.5 lp/mm. Due to the finite focal spot size of the x-ray tube, the detector blur and the reconstruction kernel functions, the system's spatial resolution does not reach the limiting spatial resolution as defined by the Nyquist's detector criteria with an ideal point source

  12. Viability of microcomputed tomography to study tropical marine worm galleries in humid muddy sediments

    Energy Technology Data Exchange (ETDEWEB)

    Pennafirme, Simone F., E-mail: sipennafirme@gmail.com [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Inst. de Biologia. Dept. de Biologia Marinha; Machado, Alessandra S.; Lima, Inaya; Suzuki, Katia N.; Lopes, Ricardo T., E-mail: machado@lin.ufrj.br, E-mail: inaya@lin.ufrj.br, E-mail: norisuzuki6@yahoo.com.br, E-mail: ricardo@lin.ufj.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), RJ (Brazil). Lab. de Instrumentacao Nuclear

    2013-07-01

    Bioturbation is an ecological process driven by organisms, which transports nutrients and gases from air/water to sediment through their galleries, by the time they feed, burrow and/or construct galleries. This exchange is vital to the maintenance of micro and macrobenthic organisms, mainly in muddy flat environments. Species with distinct galleries could create levels of bioturbation, affecting the benthic interactions. In this sense, it is fundamental developing a non-destructive method that permits identifying/quantifying the properties of these galleries. The recent advances in micro-computed tomography are allowing the high resolution 3D images generation. However, once muddy sediments are rich in organic matter and interstitial water, these would lead to motion artifacts which could, in turn, decrease the accuracy of galleries identification/quantification. In this context, the aim of this study was to develop a protocol which combines laboratory experiments and microtomography analysis in order to generate accurate 3D images of the small marine worm's galleries within humid muddy sediments. The sediment was collected at both muddy flats of Surui's and Itaipu lagoon's mangroves (RJ-Brazil), sieved (0.5mm mesh) and introduced with one individual of the marine worm Laeonereis acuta (Nereididae, Polychaeta) in each acrylic corer holders (4.4cm of internal diameter). High energy microtomography scanner was used to obtain 3D images and the setup calibration was 130 kV and 61 mA. Each acquisition image time was among 4h and 6h. Several procedures of drying remained water inside the cores were performed aiming obtaining images without movement artifacts due to circulating water, and this issue was one of the main studied parameter. In order to investigate possible chemical effects, 2ml of formalin (35%) with menthol were added to the surface of the cores. The results show that although the drying time was appropriated, the chemicals created bubbles

  13. Ultrasonic guided wave tomography for ice detection.

    Science.gov (United States)

    Zhao, Xiang; Rose, Joseph L

    2016-04-01

    Of great concern for many structures, particularly critical sections of rotary and fixed wing aircrafts, is the ability to detect ice either on grounded or in-flight vehicles. As a consequence, some work is reported here that could be useful for a variety of different industries where ice formation is an important problem. This paper presents experimental validations of a probability-based reconstruction algorithm (PRA) on ice detection of plate-like structures. The ice detection tests are performed for three different specimens: a single layer aluminum plate with a circular ice sensing array, a titanium plate with a sparse rectangular ice sensing array, and a carbon-fiber-reinforced titanium plate with an embedded ice sensing array mounted on a carbon fiber back plate. Cases from the simple to the more challenging exemplify that special modes can be used to differentiate ice from water, a sparse rectangular array could also be used for ice detection, and an ice sensing array could be further used to detect the ice on the sensor free side, a very useful application of ice sensing for aircraft wings, for example. Ice detection images for the respective cases are reconstructed to investigate the feasibility of ice sensing with ultrasonic guided wave tomography technology. The results show that the PRA based ultrasonic guided wave tomography method successfully detected and showed ice spots correctly for all three cases. This corroborates the fact that ultrasonic guided wave imaging technology could be a potential useful ice sensing tool in plate-like structures.

  14. 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.

  15. Three-dimensional microstructural investigation of high magnetization nano-micro composite fluids using x-ray microcomputed tomography

    Science.gov (United States)

    Borbáth, T.; Borbáth, I.; Günther, S.; Marinica, O.; Vékás, L.; Odenbach, S.

    2014-05-01

    X-ray microcomputed tomography was used in a three-dimensional investigation of the microstructure of suspensions of multi-domain soft iron particles in magnetic nanofluids. The measurements were performed using two different approaches: with the sample kept frozen, and with the sample under the effect of an external magnetic field. Results show that even a relatively low magnetic field gradient drives the micron-sized iron particles towards the stronger field and thus leads to a redistribution of the ferromagnetic particles in the magnetic nanofluid. Three-dimensional images of the internal microstructure of the composite magnetizable fluid (CMF) were obtained not only for the nano-micro composite system placed in a closed sample holder, but also for the spikes formed at the CMF free surface. It was demonstrated that x-ray microcomputed tomography is an efficient way to investigate the distribution and chain formation of ferromagnetic microparticles in a magnetic nanofluid carrier allowing an analysis even at a single particle level.

  16. Micro-computed tomography assisted distal femur metaphyseal blunt punch compression for determining trabecular bone strength in mice.

    Science.gov (United States)

    Sankar, Uma; Pritchard, Zachary J; Voor, Michael J

    2016-05-03

    Shorter generation time and the power of genetic manipulation make mice an ideal model system to study bone biology as well as bone diseases. However their small size presents a challenge to perform strength measurements, particularly of the weight-bearing cancellous bone in the murine long bones. We recently developed an improved method to measure the axial compressive strength of the cancellous bone in the distal femur metaphysis in mice. Transverse micro-computed tomography image slices that are 7µm thick were used to locate the position where the epiphysis-metaphysis transition occurs. This enabled the removal of the distal femur epiphysis at the exact transition point exposing the full extent of metaphyseal trabecular bone, allowing more accurate and consistent measurement of its strength. When applied to a murine model system consisting of five month old male wild-type (WT) and Ca(2+)/calmodulin dependent protein kinase kinase 2 (CaMKK2) knockout (KO) Camkk2(-/-) mice that possess recorded differences in trabecular bone volume, data collected using this method showed good correlation between bone volume fraction and strength of trabecular bone. In combination with micro-computed tomography and histology, this method will provide a comprehensive and consistent assessment of the microarchitecture and tissue strength of the cancellous bone in murine mouse models.

  17. Field trials results of guided wave tomography

    Science.gov (United States)

    Volker, Arno; van Zon, Tim; van der Leden, Edwin

    2015-03-01

    Corrosion is one of the industries major issues regarding the integrity of assets. Guided wave travel time tomography is a method capable of providing an absolute wall thickness map. This method is currently making the transition from the laboratory to the field. For this purpose a dedicated data acquisition system and special purpose EMAT sensor rings have been developed. The system can be deployed for permanent monitoring and inspections. Field trials have been conducted on various pipes with different diameters, containing either liquid or gas. The main focus has been on pipe supports. The results demonstrate the successful operation of the technology in the field. Expected corrosion damage was clearly visible on the produced results enabling asset owner to make calculated decisions on the pipelines safety, maintenance and operations.

  18. Visualizing polymeric bioresorbable scaffolds with three-dimensional image reconstruction using contrast-enhanced micro-computed tomography.

    Science.gov (United States)

    Tu, Sheng; Hu, Fudong; Cai, Wei; Xiao, Liyan; Zhang, Linlin; Zheng, Hong; Jiang, Qiong; Chen, Lianglong

    2017-05-01

    There are no previous studies showing how to visualize polymeric bioresorbable scaffolds (BRSs) by micro-computed tomography (mCT). There are no previous studies showing how to visualize polymeric bioresorbable scaffolds (BRSs) by micro-computed tomography (mCT). This study aimed to explore the feasibility of detecting polymeric BRS with 3-dimensional reconstruction of BRS images by contrast-enhanced mCT and to determine the optimal imaging settings. BRSs, made of poly-L-lactic acid (PLLA), were implanted in coronary bifurcation models. Five treatments were conducted to examine an optimal condition for imaging BRSs: Baseline treatment, samples were filled with normal saline and scanned with mCT immediately; Treatment-1, -2, -3 and -4, samples were filled with contrast medium and scanned with mCT immediately and 1, 2 and 3 h thereafter, corresponding to soaking time of contrast medium of 0, 1, 2 and 3 h. Compared to Baseline, mCT scanning completely discriminate the scaffold struts from the vascular lumen immediately after filling the samples with contrast agent but not from the vascular wall until the contrast agent soaking time was more than 2 h (Treatment-3 and -4). By setting 10-15 HU as a cut-point of CT values, the scaffold strut detectable rate at Baseline and Teatment-1, -2, -3 and -4 were 1.23 ± 0.31%, 1.65 ± 0.26%, 58.14 ± 12.84%, 97.97 ± 1.43% and 98.90 ± 0.38%, respectively (Treatment-3 vs. Treatment-2, p scaffold struts from the surrounding structures in the phantom samples.

  19. Resolution effect in X-ray microcomputed tomography imaging and small pore's contribution to permeability for a Berea sandstone

    Science.gov (United States)

    Peng, Sheng; Marone, Federica; Dultz, Stefan

    2014-03-01

    Resolution selection when using X-ray microcomputed tomography should be made based on the compromise between accuracy and representativeness. The question is then how accurate is accurate enough, that is, how small a pore is small enough to be ignored without generating misleading results on pore representation and subsequent flow properties such as permeability. In this study, synchrotron X-ray microcomputed tomographic scans of a Berea sandstone sample were acquired for two resolutions (with 1.85 and 5.92 μm pixel width). Higher resolution images resolve more small pores, and have similar large pores as the lower resolution images. Pore characterization and permeability estimation were conducted based on these two sets of images. The pore parameters and permeability were also measured for another larger sample from the same rock fragment through laboratory experiments. The comparison between the different resolution image analyses and the laboratory measurement indicates that small pores contribute to larger porosity, smaller tortuosity, and larger surface area, but do not influence permeability significantly. Therefore, relatively low resolution (pixel width up to 5.92 μm) can be used for Berea sandstone when permeability is the focus. However, use of even lower resolution needs to be careful since lower resolution not only excludes more small pores, but also has the potential to overestimate the pore size and thereby the permeability. Kozeny-Carman equation was used to estimate the permeability with geometric and diffusional tortuosity. The results indicate that the latter tortuosity can serve better for the permeability estimation than the former.

  20. Comparisons of the diagnostic accuracies of optical coherence tomography, micro-computed tomography, and histology in periodontal disease: an ex vivo study

    Science.gov (United States)

    2017-01-01

    Purpose Optical coherence tomography (OCT) is a noninvasive diagnostic technique that may be useful for both qualitative and quantitative analyses of the periodontium. Micro-computed tomography (micro-CT) is another noninvasive imaging technique capable of providing submicron spatial resolution. The purpose of this study was to present periodontal images obtained using ex vivo dental OCT and to compare OCT images with micro-CT images and histologic sections. Methods Images of ex vivo canine periodontal structures were obtained using OCT. Biologic depth measurements made using OCT were compared to measurements made on histologic sections prepared from the same sites. Visual comparisons were made among OCT, micro-CT, and histologic sections to evaluate whether anatomical details were accurately revealed by OCT. Results The periodontal tissue contour, gingival sulcus, and the presence of supragingival and subgingival calculus could be visualized using OCT. OCT was able to depict the surface topography of the dentogingival complex with higher resolution than micro-CT, but the imaging depth was typically limited to 1.2–1.5 mm. Biologic depth measurements made using OCT were a mean of 0.51 mm shallower than the histologic measurements. Conclusions Dental OCT as used in this study was able to generate high-resolution, cross-sectional images of the superficial portions of periodontal structures. Improvements in imaging depth and the development of an intraoral sensor are likely to make OCT a useful technique for periodontal applications. PMID:28261522

  1. Recent developments in guided wave travel time tomography

    NARCIS (Netherlands)

    Zon, A.T. van; Volker, A.W.F.

    2014-01-01

    The concept of predictive maintenance using permanent sensors that monitor the integrity of an installation is an interesting addition to the current method of periodic inspections. Guided wave tomography had been developed to create a map of the wall thickness using the travel times of guided waves

  2. Evaluating the microstructure of human brain tissues using synchrotron radiation-based micro-computed tomography

    Science.gov (United States)

    Schulz, Georg; Morel, Anne; Imholz, Martha S.; Deyhle, Hans; Weitkamp, Timm; Zanette, Irene; Pfeiffer, Franz; David, Christian; Müller-Gerbl, Magdalena; Müller, Bert

    2010-09-01

    Minimally invasive deep brain neurosurgical interventions require a profound knowledge of the morphology of the human brain. Generic brain atlases are based on histology including multiple preparation steps during the sectioning and staining. In order to correct the distortions induced in the anisotropic, inhomogeneous soft matter and therefore improve the accuracy of brain atlases, a non-destructive 3D imaging technique with the required spatial and density resolution is of great significance. Micro computed tomography provides true micrometer resolution. The application to post mortem human brain, however, is questionable because the differences of the components concerning X-ray absorption are weak. Therefore, magnetic resonance tomography has become the method of choice for three-dimensional imaging of human brain. Because the spatial resolution of this method is limited, an alternative has to be found for the three-dimensional imaging of cellular microstructures within the brain. Therefore, the present study relies on the synchrotron radiationbased micro computed tomography in the recently developed grating-based phase contrast mode. Using data acquired at the beamline ID 19 (ESRF, Grenoble, France) we demonstrate that grating-based tomography yields premium images of human thalamus, which can be used for the correction of histological distortions by 3D non-rigid registration.

  3. 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

  4. Micro-computed tomography and histomorphometric analysis of human alveolar bone repair induced by laser phototherapy: a pilot study.

    Science.gov (United States)

    Romão, M M A; Marques, M M; Cortes, A R G; Horliana, A C R T; Moreira, M S; Lascala, C A

    2015-12-01

    Immediate dental implant placement in the molar region is critical, because of the high amount of bone loss and the discrepancy between alveolar crest thickness and the implant platform. Laser phototherapy (LPT) improves bone repair. The aim of this study was to evaluate the human alveolar bone repair 40 days after molar extraction in patients submitted to LPT. Twenty patients were selected for this randomized controlled clinical trial; 10 underwent LPT (laser group) with a GaAlAs diode laser (808 nm, 100 mW, 0.04 cm(2), 75 J/cm(2), 30s per point, 3 J per point, at five points). The control group patients (n=10) were not irradiated. Forty days later, the tissue formed inside the sockets was analyzed by micro-computed tomography and histomorphometry. Data from the two groups were compared with Student's t-test and Pearson's correlation test. The relative bone volume was significantly higher in the laser group (Palveolar bone repair after molar extraction, leading to a more homogeneous trabecular configuration represented by thin and close trabeculae.

  5. 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.

  6. Phase-Contrast Micro-Computed Tomography Measurements of the Intraocular Pressure-Induced Deformation of the Porcine Lamina Cribrosa.

    Science.gov (United States)

    Coudrillier, Baptiste; Geraldes, Diogo M; Vo, Nghia T; Atwood, Robert; Reinhard, Christina; Campbell, Ian C; Raji, Yazdan; Albon, Julie; Abel, Richard L; Ethier, C Ross

    2016-04-01

    The lamina cribrosa (LC) is a complex mesh-like tissue in the posterior eye. Its biomechanical environment is thought to play a major role in glaucoma, the second most common cause of blindness. Due to its small size and relative inaccessibility, high-resolution measurements of LC deformation, important in characterizing LC biomechanics, are challenging. Here we present a novel noninvasive imaging method, which enables measurement of the three-dimensional deformation of the LC caused by acute elevation of intraocular pressure (IOP). Posterior segments of porcine eyes were imaged using synchrotron radiation phase contrast micro-computed tomography (PC μCT) at IOPs between 6 and 37 mmHg. The complex trabecular architecture of the LC was reconstructed with an isotropic spatial resolution of 3.2 μm. Scans acquired at different IOPs were analyzed with digital volume correlation (DVC) to compute full-field deformation within the LC. IOP elevation caused substantial tensile, shearing and compressive devformation within the LC, with maximum tensile strains at 30 mmHg averaging 5.5%, and compressive strains reaching 20%. We conclude that PC μCT provides a novel high-resolution method for imaging the LC, and when combined with DVC, allows for full-field 3D measurement of ex vivo LC biomechanics at high spatial resolution.

  7. Analysis of maize ( Zea mays ) kernel density and volume using microcomputed tomography and single-kernel near-infrared spectroscopy.

    Science.gov (United States)

    Gustin, Jeffery L; Jackson, Sean; Williams, Chekeria; Patel, Anokhee; Armstrong, Paul; Peter, Gary F; Settles, A Mark

    2013-11-20

    Maize kernel density affects milling quality of the grain. Kernel density of bulk samples can be predicted by near-infrared reflectance (NIR) spectroscopy, but no accurate method to measure individual kernel density has been reported. This study demonstrates that individual kernel density and volume are accurately measured using X-ray microcomputed tomography (μCT). Kernel density was significantly correlated with kernel volume, air space within the kernel, and protein content. Embryo density and volume did not influence overall kernel density. Partial least-squares (PLS) regression of μCT traits with single-kernel NIR spectra gave stable predictive models for kernel density (R(2) = 0.78, SEP = 0.034 g/cm(3)) and volume (R(2) = 0.86, SEP = 2.88 cm(3)). Density and volume predictions were accurate for data collected over 10 months based on kernel weights calculated from predicted density and volume (R(2) = 0.83, SEP = 24.78 mg). Kernel density was significantly correlated with bulk test weight (r = 0.80), suggesting that selection of dense kernels can translate to improved agronomic performance.

  8. A micro-computed tomography study of the negotiation and anatomical feature in apical root canal of mandibular molars.

    Science.gov (United States)

    Min, Yi; Ma, Jing-Zhi; Shen, Ya; Cheung, Gary Shun-Pan; Gao, Yuan

    2016-11-01

    The aim of this study was to investigate the clinical negotiation of various apical anatomic features of the mandibular first molars in a Chinese population using micro-computed tomography (micro-CT). A total of 152 mandibular first molars were scanned with micro-CT at 30 µm resolution. The apical 5 mm of root canal (ARC) was reconstructed three dimensionally and classified. Subsequently, the access cavity was prepared with the ARC anatomy blinded to the operator. The ARC was negotiated with a size 10 K file with or without precurve. Information on the ability to obtain a reproducible glide path was recorded. The anatomical classification of ARC was Type I with 68.45% in mandibular first molars. The negotiation result of ARC with Category i was 387 canals (74.00%). With a bent negotiating file, 96 canals were negotiated, including 88 reproducible glide paths (Category ii) and 8 irregular glide paths (Category iii). About 7.65% canals could not be negotiated with patency successfully (Category iv). The statistical analyze shown the anatomic feature of ARC had effect on the negotiation of ARC (p negotiation. The category of negotiation in ARC would be helpful in the using of NiTi rotary instruments. Negotiation of ARC to the working length with patency should be careful and skillful because of the complexities of ARC. SCANNING 38:819-824, 2016. © 2016 Wiley Periodicals, Inc.

  9. 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

    2015-06-01

    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. © 2015 Wiley Periodicals, Inc.

  10. Nondestructive material characterization of meteorites with synchrotron-based high energy x-ray phase micro-computed tomography

    Science.gov (United States)

    Liu, Huiqiang; Xiao, Tiqiao; Xie, Honglan; Fu, Yanan; Zhang, Xueliang; Fan, Xiaoxi

    2017-02-01

    Synchrotron radiation based x-ray propagation-based micro-computed tomography (SRPCT) has been widely used to nondestructively access 3D structural information in many fields in the last decade. However, for strongly absorbed objects with small density-differential compositions, conventional SRPCT technique fails in providing high-contrast images for visualization of objects characteristic information except edge-enhancements at interfaces or boundaries of samples. In this study, we successfully employed the SRPCT technique with phase retrieval, the high energy x-ray phase-attenuation-duality (PAD) algorithm, into nondestructive material characterization of invaluable meteorite samples due to the greatly enhanced phase-contrast of different bulk material areas, as compared to conventional SRPCT on equal dose basis. Our experimental results demonstrated the PAD-SRPCT technique is superior to conventional SRPCT technique to access density and structure distributions of different meteorite compositions with high density resolution, owing to the striking contrast-to-noise ratio (CNR). In addition, a new mass-density measurement method was presented to estimate the mass density of different compositions in the meteorite sample based on the calibration of the imaging system.

  11. 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.)

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

    Science.gov (United States)

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

    2012-08-01

    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, influence the dimensional measurement properties of the system as a whole. Therefore, it is important to know what leads to, and what are the consequences of, e.g., a geometrical misalignment of the scanner system, image unsharpness (blurring), or noise or image artefacts. In our study, the two main 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, it will minimize the user's influence by a systematic line of action, taking into account the physical and technical limitations and influences on dimensional measurements.

  13. 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.

  14. 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.

  15. 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.

  16. A novel in vivo vascular imaging approach for hierarchical quantification of vasculature using contrast enhanced micro-computed tomography.

    Directory of Open Access Journals (Sweden)

    Laura Nebuloni

    Full Text Available The vasculature of body tissues is continuously subject to remodeling processes originating at the micro-vascular level. The formation of new blood vessels (angiogenesis is essential for a number of physiological and pathophysiological processes such as tissue regeneration, tumor development and the integration of artificial tissues. There are currently no time-lapsed in vivo imaging techniques providing information on the vascular network at the capillary level in a non-destructive, three-dimensional and high-resolution fashion. This paper presents a novel imaging framework based on contrast enhanced micro-computed tomography (micro-CT for hierarchical in vivo quantification of blood vessels in mice, ranging from largest to smallest structures. The framework combines for the first time a standard morphometric approach with densitometric analysis. Validation tests showed that the method is precise and robust. Furthermore, the framework is sensitive in detecting different perfusion levels after the implementation of a murine ischemia-reperfusion model. Correlation with both histological data and micro-CT analysis of vascular corrosion casts confirmed accuracy of the method. The newly developed time-lapsed imaging approach shows high potential for in vivo monitoring of a number of different physiological and pathological conditions in angiogenesis and vascular development.

  17. Impact of Mineral Precipitation on Flow and Mixing in Porous Media Determined by Microcomputed Tomography and MRI.

    Science.gov (United States)

    Bray, Joshua M; Lauchnor, Ellen G; Redden, George D; Gerlach, Robin; Fujita, Yoshiko; Codd, Sarah L; Seymour, Joseph D

    2017-02-07

    Precipitation reactions influence transport properties in porous media and can be coupled to advective and dispersive transport. For example, in subsurface environments, mixing of groundwater and injected solutions can induce mineral supersaturation of constituents and drive precipitation reactions. Magnetic resonance imaging (MRI) and microcomputed tomography (μ-CT) were employed as complementary techniques to evaluate advection, dispersion, and formation of precipitate in a 3D porous media flow cell. Two parallel fluids were flowed concentrically through packed glass beads under two relative flow rates with Na2CO3 and CaCl2 in the inner and outer fluids, respectively. CaCO3 became supersaturated and formed a precipitate at the mixing interface between the two solutions. Spatial maps of changing local velocity fields and dispersion in the flow cell were generated from MRI, while high resolution μ-CT imaging visualized the precipitate formed in the porous media. Formation of a precipitate minimized dispersive and advective transport between the two fluids and the shape of the precipitation front was influenced by the relative flow rates. This work demonstrates that the combined use of MRI and μ-CT can be highly complementary in the study of reactive transport processes in porous media.

  18. Airway remodeling in a mouse asthma model assessed by in-vivo respiratory-gated micro-computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Lederlin, Mathieu; Montaudon, Michel [Universite Bordeaux 2, Laboratoire de Physiologie Cellulaire Respiratoire, Bordeaux (France); Institut National de la Sante et de la Recherche Medicale (INSERM), U885, Bordeaux (France); CHU Bordeaux, Unite d' Imagerie Thoracique, Pessac (France); Ozier, Annaig; Begueret, Hugues; Ousova, Olga; Marthan, Roger; Berger, Patrick [Universite Bordeaux 2, Laboratoire de Physiologie Cellulaire Respiratoire, Bordeaux (France); Institut National de la Sante et de la Recherche Medicale (INSERM), U885, Bordeaux (France); Laurent, Francois [Universite Bordeaux 2, Laboratoire de Physiologie Cellulaire Respiratoire, Bordeaux (France); Institut National de la Sante et de la Recherche Medicale (INSERM), U885, Bordeaux (France); CHU Bordeaux, Unite d' Imagerie Thoracique, Pessac (France); CHU de Bordeaux, Hopital du Haut-Leveque, Hopital Cardiologique, Unite d' Imagerie Thoracique et Cardiovasculaire, Pessac (France)

    2010-01-15

    The aim of our study was to evaluate the feasibility of non-invasive respiratory-gated micro-computed tomography (micro-CT) for assessment of airway remodelling in a mouse asthma model. Six female BALB/c mice were challenged intranasally with ovalbumin. A control group of six mice received saline inhalation. All mice underwent plethysmographic study and micro-CT. For each mouse, peribronchial attenuation values of 12 bronchi were measured, from which a peribronchial density index (PBDI) was computed. Mice were then sacrificed and lungs examined histologically. Final analysis involved 10 out of 12 mice. Agreement of measurements across observers and over time was very good (intraclass correlation coefficients: 0.94-0.98). There was a significant difference in PBDI between asthmatic and control mice (-210 vs. -338.9 HU, P=0.008). PBDI values were correlated to bronchial muscle area (r=0.72, P=0.018). This study shows that respiratory-gated micro-CT may allow non-invasive monitoring of bronchial remodelling in asthmatic mice and evaluation of innovative treatment effects. (orig.)

  19. Characterization of Fatigue Fractures in Closed-Cell Aluminum Foam Using x-ray Micro-Computed Tomography

    Science.gov (United States)

    Kafka, O. L.; Ingraham, M. D.; Morrison, D. J.; Issen, K. A.

    2014-03-01

    A post-mortem study of Alporas closed-cell aluminum foam specimens previously failed under strain-controlled fully reversed tension-compression fatigue was conducted using x-ray micro-computed tomography (μCT). Volumetric renders of the 3D structure of the material were produced. Fractures were identified and marked throughout voxel-based images of the specimens. This produced a 3D plot of fracture locations. At high strain amplitudes (0.175-0.5%), fractures formed an interconnected planar zone oriented approximately perpendicular to the loading axis; typically, the angle of the plane differed from that of a tension failure. Conversely, at low strain amplitudes (0.05-0.1%), short fractures have been formed diffusely within the specimen. In both cases, observed fractures were tortuous. Our previous work with surface strain mapping via digital image correlation (DIC) suggested that for all strain amplitudes, a crack, evidenced by a zone of high extensile strain, was formed and propagated through the material. This result was confirmed at high strain amplitudes, but not at low strain amplitudes. The discrepancy is attributed to three potential causes. Using DIC, short cracks cannot be accurately resolved with relatively coarse light intensity patterns. DIC images indicate fractures under load, while μCT imaging was conducted under zero load. Finally, the localized extension seen in DIC images could be attributed to strain with no resultant fractures.

  20. 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.

  1. The root canal morphology in mandibular first premolars: a comparative evaluation of cone-beam computed tomography and micro-computed tomography.

    Science.gov (United States)

    Zhang, Dan; Chen, Junhong; Lan, Guihua; Li, Min; An, Jianping; Wen, Xiujie; Liu, Luchuan; Deng, Manjing

    2017-05-01

    This study evaluated the accuracy of cone-beam computed tomography (CBCT) in detecting the root canal morphology of mandibular first premolars using micro-computed tomography (micro-CT) as a reference standard. In total, 143 extracted human mandibular first premolars were selected and scanned using micro-CT and CBCT. The acquired images were used to evaluate the root canal morphology in each tooth, and evaluations were repeated after 2 weeks. The root canal configurations observed on the three-dimensional images were recorded, and the findings from both modalities were compared using chi-square tests. The actual agreement between the two modalities was assessed using kappa statistics. In total, the root morphologies in 136 mandibular first premolars were consistently identified by both CBCT and micro-CT: type I in 104, type III in five, type V in 20, and type IX in seven. Of the remaining seven teeth, the morphology in two, one, and four teeth was identified as type I, type VII, and type IX (type 1-3 in two and type 1-2-3 in two), respectively, by micro-CT and misdiagnosed as type III, type V, and type V, respectively, by CBCT. There were no significant differences between the two modalities with regard to the accurate detection of root canal configurations, with a kappa value of 0.886 for the actual agreement. Although CBCT may be accurate in detecting the root canal configuration in mandibular first premolars, it produces poorer image details compared with micro-CT. CBCT is a reliable radiological technique, but its accuracy in detecting details of the root canal morphology in mandibular first premolars, especially in some complex root canal configurations, needs to be improved.

  2. Three-dimensional arrangement of β-tricalcium phosphate granules evaluated by microcomputed tomography and fractal analysis.

    Science.gov (United States)

    Ndiaye, Mambaye; Terranova, Lisa; Mallet, Romain; Mabilleau, Guillaume; Chappard, Daniel

    2015-01-01

    The macrophysical properties of granular biomaterials used to fill bone defects have rarely been considered. Granules of a given biomaterial occupy three-dimensional (3-D) space when packed together and create a macroporosity suitable for the invasion of vascular and bone cells. Granules of β-tricalcium phosphate were prepared using polyurethane foam technology and increasing the amount of material powder in the slurry (10, 11, 15, 18, 21 and 25 g). After sintering, granules of 1000-2000 μm were prepared by sieving. They were analyzed morphologically by scanning electron microscopy and placed in polyethylene test tubes to produce 3-D scaffolds. Microcomputed tomography (microCT) was used to image the scaffolds and to determine porosity and fractal dimension in three dimensions. Two-dimensional sections of the microCT models were binarized and used to compute classical morphometric parameters describing porosity (interconnectivity index, strut analysis and star volumes) and fractal dimensions. In addition, two newly important fractal parameters (lacunarity and succolarity) were measured. Compression analysis of the stacks of granules was done. Porosity decreased as the amount of material in the slurry increased but non-linear relationships were observed between microarchitectural parameters describing the pores and porosity. Lacunarity increased in the series of granules but succolarity (reflecting the penetration of a fluid) was maximal in the 15-18 g groups and decreased noticeably in the 25 g group. The 3-D arrangement of biomaterial granules studied by these new fractal techniques allows the optimal formulation to be derived based on the lowest amount of material, suitable mechanical resistance during crushing and the creation of large interconnected pores. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  3. 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.

  4. Three-dimensional microstructural analysis of human lumber vertebrae using microcomputed tomography in bone metastasis from prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Tamada, Tsutomu [Kawasaki Medical School, Kurashiki, Okayama (Japan)

    2000-11-01

    Prostate cancer frequently metastasizes to bone, inducing osteosclerotic lesions. However, the morphological details of bone metastasis of prostate cancer have not been clarified. The trabecular bone structure of bone metastasis from prostate cancer was investigated in three dimensions using microcomputed tomography (micro-CT). A total of 17 cubes of the lumber spine of a 77-year-old man with prostate cancer were excised post mortem: four of them from non-metastatic and the rest from metastatic sites. The samples were measured using micro-CT with a resolution of 23.2 {mu}m and the standard structural indices and degree of anisotropy were computed. After micro-CT measurement, the samples were tested in a destructive manner for the assessment of mechanical properties. Samples from the metastatic sites showed significantly higher values than those from non-metastatic sites for bone volume (BV), bone surface (BS), bone volume fraction (BV/TV), trabecular thickness (Tb.Th), and trabecular number (Tb.N) (p<0.005). Bone surface density (BS/BV) and trabecular separation (Tb.Sp) were significantly higher in the samples from non-metastatic sites (p<0.001). Samples from metastatic sites showed a more isotropic arrangement of trabecular bone than those from non-metastatic sites. Three-dimensionally reconstructed images depicted several different patterns of sclerotic bone metastasis, and osteolytic appearance was observed in all of them. Structural parameters such as BV/TV were well correlated with the mechanical properties (r=0.899). The present study clarified the trabecular microstructure of bone metastasis from prostate cancer and suggests that both osteolysis and osteogenesis progress while interacting with each other in all phases of bone metastasis. (author)

  5. 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.

  6. Characterization of the Distal Esophagus High-Pressure Zone with Manometry, Ultrasound and Micro-Computed Tomography

    Science.gov (United States)

    Vegesna, Anil K.; Sloan, Joshua A.; Singh, Baltej; Phillips, Steven J; Braverman, Alan S.; Barbe, Mary F.; Ruggieri, Michael R.; Miller, Larry S.

    2012-01-01

    Background We sought to determine how the individual components of the distal esophagus and proximal stomach form the gastroesophageal junction high-pressure zone (GEJHPZ) anti-reflux barrier. Methods An endoscopic ultrasound/manometry catheter was pulled through the proximal stomach and distal esophagus in 20 normal subjects. The axial length and width of individual structures on endoscopic ultrasound were measured. The anatomic orientation of gastroesophageal junction (GEJ) components was examined in two organ donor specimens using micro-computed tomography (micro-CT). Key Results The three distinct structures identified within the GEJHPZ, from distal to proximal, were: the gastric clasp and sling muscle fiber complex, crural diaphragm, and lower esophageal circular smooth muscle fibers (LEC). The LEC was statistically significantly thicker than adjacent esophageal muscles. These structures were associated with 3 pressure peaks. The pressure peak produced by the clasp/sling fiber complex often overlapped with the pressure peak from the crural diaphragm. The most proximal peak, associated with the LEC, was significantly greater and bimodal in 9 of 20 subjects. This bimodal LEC pressure peak correlated with two areas of thickened muscle observed with ultrasound. Micro-CT of GEJ from organ donors confirmed the two areas of thickened muscle. Conclusions and inferences Three distinct anatomic structures, the clasp and sling muscle fibers, crural diaphragm, and LEC combine to form the anti-reflux barrier of the proximal stomach and distal esophagus. The clasp and sling muscle fibers combine with the crural diaphragm to form a distal pressure profile. The more proximal LEC has a bimodal pressure profile in some patients. PMID:22998376

  7. Age estimation during the blow fly intra-puparial period: a qualitative and quantitative approach using micro-computed tomography.

    Science.gov (United States)

    Martín-Vega, Daniel; Simonsen, Thomas J; Wicklein, Martina; Hall, Martin J R

    2017-05-04

    Minimum post-mortem interval (minPMI) estimates often rely on the use of developmental data from blow flies (Diptera: Calliphoridae), which are generally the first colonisers of cadavers and, therefore, exemplar forensic indicators. Developmental data of the intra-puparial period are of particular importance, as it can account for more than half of the developmental duration of the blow fly life cycle. During this period, the insect undergoes metamorphosis inside the opaque, barrel-shaped puparium, formed by the hardening and darkening of the third instar larval cuticle, which shows virtually no external changes until adult emergence. Regrettably, estimates based on the intra-puparial period are severely limited due to the lack of reliable, non-destructive ageing methods and are frequently based solely on qualitative developmental markers. In this study, we use non-destructive micro-computed tomography (micro-CT) for (i) performing qualitative and quantitative analyses of the morphological changes taking place during the intra-puparial period of two forensically relevant blow fly species, Calliphora vicina and Lucilia sericata, and (ii) developing a novel and reliable method for estimating insect age in forensic practice. We show that micro-CT provides age-diagnostic qualitative characters for most 10% time intervals of the total intra-puparial period, which can be used over a range of temperatures and with a resolution comparable to more invasive and time-consuming traditional imaging techniques. Moreover, micro-CT can be used to yield a quantitative measure of the development of selected organ systems to be used in combination with qualitative markers. Our results confirm micro-CT as an emerging, powerful tool in medico-legal investigations.

  8. A Quantitative Volumetric Micro-Computed Tomography Method to Analyze Lung Tumors in Genetically Engineered Mouse Models

    Directory of Open Access Journals (Sweden)

    Brian B. Haines

    2009-01-01

    Full Text Available Two genetically engineered, conditional mouse models of lung tumor formation, K-rasLSL-G12D and K-rasLSL-G12D/p53LSL-R270H, are commonly used to model human lung cancer. Developed by Tyler Jacks and colleagues, these models have been invaluable to study in vivo lung cancer initiation and progression in a genetically and physiologically relevant context. However, heterogeneity, multiplicity and complexity of tumor formation in these models make it challenging to monitor tumor growth in vivo and have limited the application of these models in oncology drug discovery. Here, we describe a novel analytical method to quantitatively measure total lung tumor burden in live animals using micro-computed tomography imaging. Applying this methodology, we studied the kinetics of tumor development and response to targeted therapy in vivo in K-ras and K-ras/p53 mice. Consistent with previous reports, lung tumors in both models developed in a time- and dose (Cre recombinase-dependent manner. Furthermore, the compound K-rasLSL-G12D/p53LSL-R270H mice developed tumors faster and more robustly than mice harboring a single K-rasLSL-G12D oncogene, as expected. Erlotinib, a small molecule inhibitor of the epidermal growth factor receptor, significantly inhibited tumor growth in K-rasLSL-G12D/p53LSL-R270H mice. These results demonstrate that this novel imaging technique can be used to monitor both tumor progression and response to treatment and therefore supports a broader application of these genetically engineered mouse models in oncology drug discovery and development.

  9. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-05-10

    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{sub 4}) solution. As a tissue-staining contrast agent, OsO{sub 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{sub 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{sup -/-}) mice at 10 {mu}m resolution. The results show that walls of coronary arteries as small as 45 {mu}m 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{sub 4} and micro-CT permits the visualization of the coronary artery wall in intact mouse hearts.

  11. Use of micro-computed tomography for the assessment of periapical lesions in small rodents: a systematic review.

    Science.gov (United States)

    Kalatzis-Sousa, N G; Spin-Neto, R; Wenzel, A; Tanomaru-Filho, M; Faria, G

    2017-04-01

    This systematic review aimed to evaluate the literature on the acquisition-, reconstruction- and analysis parameters of micro-computed tomography (micro-CT) for the assessment of periapical lesions in rats and mice, and to illustrate the effect of variation in these parameters. The PubMed database was searched from 2000 to January 2015 (English-language publications) for reports on the use of micro-CT to evaluate periapical lesions in rats and mice. QUADAS criteria were used to rate the quality of the studies. To illustrate the effect of variations in acquisition-, reconstruction-, and analysis parameters on images of periapical lesions, micro-CT examination of two hemi-mandibles of mice, with periapical lesions around the first molar was undertaken. Twenty-one studies were identified, which analysed periapical lesions in rats or mice using micro-CT. According to the QUADAS, no study was classified as high-, seven were classified as moderate-, and 14 as low quality. The effect of variation in parameters was that voxel size may interfere with image sharpness, reconstruction may interfere with image sharpness and contrast, and inadequate plane orientation may alter the size of the periapical lesion. Nonpersonalized ROIs resulted in areas that were not part of the periapical lesion. Changing the limits of the threshold for bone-tissue visualization increased lesion size. There is no defined protocol for acquiring and analysing micro-CT images of periapical lesions in rats and mice. Furthermore, acquisition-, reconstruction- and analysis parameters are not adequately explained, which may compromise the scientific impact of the studies. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  12. Integration and evaluation of a needle-positioning robot with volumetric microcomputed tomography image guidance for small animal stereotactic interventions

    Energy Technology Data Exchange (ETDEWEB)

    Waspe, Adam C.; McErlain, David D.; Pitelka, Vasek; Holdsworth, David W.; Lacefield, James C.; Fenster, Aaron [Biomedical Engineering Graduate Program and Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, London, Ontario N6A 5K8 (Canada); Department of Medical Biophysics and Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, London, Ontario N6A 5K8 (Canada); Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario N6A 5C1 (Canada); Biomedical Engineering Graduate Program, Department of Medical Biophysics, Department of Medical Imaging, Department of Surgery, and Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, London, Ontario N6A 5K8 (Canada); Biomedical Engineering Graduate Program, Department of Electrical and Computer Engineering, Department of Medical Biophysics, and Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, London, Ontario N6A 5K8 (Canada); Biomedical Engineering Graduate Program, Department of Medical Biophysics, Department of Medical Imaging, and Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, London, Ontario N6A 5K8 (Canada)

    2010-04-15

    Purpose: Preclinical research protocols often require insertion of needles to specific targets within small animal brains. To target biologically relevant locations in rodent brains more effectively, a robotic device has been developed that is capable of positioning a needle along oblique trajectories through a single burr hole in the skull under volumetric microcomputed tomography (micro-CT) guidance. Methods: An x-ray compatible stereotactic frame secures the head throughout the procedure using a bite bar, nose clamp, and ear bars. CT-to-robot registration enables structures identified in the image to be mapped to physical coordinates in the brain. Registration is accomplished by injecting a barium sulfate contrast agent as the robot withdraws the needle from predefined points in a phantom. Registration accuracy is affected by the robot-positioning error and is assessed by measuring the surface registration error for the fiducial and target needle tracks (FRE and TRE). This system was demonstrated in situ by injecting 200 {mu}m tungsten beads into rat brains along oblique trajectories through a single burr hole on the top of the skull under micro-CT image guidance. Postintervention micro-CT images of each skull were registered with preintervention high-field magnetic resonance images of the brain to infer the anatomical locations of the beads. Results: Registration using four fiducial needle tracks and one target track produced a FRE and a TRE of 96 and 210 {mu}m, respectively. Evaluation with tissue-mimicking gelatin phantoms showed that locations could be targeted with a mean error of 154{+-}113 {mu}m. Conclusions: The integration of a robotic needle-positioning device with volumetric micro-CT image guidance should increase the accuracy and reduce the invasiveness of stereotactic needle interventions in small animals.

  13. Application of Micro-Computed Tomography with Iodine Staining to Cardiac Imaging, Segmentation and Computational Model Development

    Science.gov (United States)

    Aslanidi, OV; Nikolaidou, T; Zhao, J; Smaill, BH; Gilbert, SH; Holden, AV; Lowe, T; Withers, PJ; Jarvis, JC; Stephenson, RS; Hart, G; Hancox, JC; Boyett, MR; Zhang, H

    2012-01-01

    Micro-computed tomography (micro-CT) has been widely used to generate high-resolution 3D tissue images from small animals non-destructively, especially for mineralized skeletal tissues. However, its application to the analysis of soft cardiovascular tissues has been limited by poor inter-tissue contrast. Recent ex vivo studies have shown that contrast between muscular and connective tissue in micro-CT images can be enhanced by staining with iodine. In the present study, we apply this novel technique for imaging of cardiovascular structures in canine hearts. We optimize the method to obtain high resolution X-ray micro-CT images of the canine atria and its distinctive regions - including the Bachmann’s bundle, atrioventricular node, pulmonary arteries and veins - with clear inter-tissue contrast. The imaging results are used to reconstruct and segment the detailed 3D geometry of the atria. Structure tensor analysis shows that the arrangement of atrial fibres can also be characterised using the enhanced micro-CT images, as iodine preferentially accumulates within the muscular fibres rather than in connective tissues. This novel technique can be particularly useful in non-destructive imaging of 3D cardiac architectures from large animals and humans, due to the combination of relatively high speed (~1 hour/scan of a large canine heart) and high voxel resolution (36 μm) provided. In summary, contrast micro-CT facilitates fast and non-destructive imaging and segmenting of detailed 3D cardiovascular geometries, as well as measuring fibre orientation, which are crucial in constructing biophysically detailed computational cardiac models. PMID:22829390

  14. 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.

  15. Evaluation of the in vitro degradation of macroporous hydrogels using gravimetry, confined compression testing, and microcomputed tomography.

    Science.gov (United States)

    Behravesh, Esfandiar; Timmer, Mark D; Lemoine, Jeremy J; Liebschner, Michael A K; Mikos, Antonios G

    2002-01-01

    This study investigated the in vitro degradation characteristics of macroporous hydrogels based on poly(propylene fumarate-co-ethylene glycol) (P(PF-co-EG)). Four formulations were fabricated to test the effect of porosity and cross-linking density on the degradation of the resulting macroporous hydrogels. Macroporosity was introduced by the addition of sodium bicarbonate and ascorbic acid, the precursors of the carbon dioxide porogen, in the initiation system for the hydrogel cross-linking. Macroporous hydrogels with porosities of 0.80 +/- 0.03 and 0.89 +/- 0.03 were synthesized by the addition of sodium bicarbonate of concentrations 40 and 80 mg/mL and ascorbic acid of concentrations 0.05 and 0.1 mol/L, respectively. Poly(ethylene glycol) diacrylate (PEG-DA) was utilized as a cross-linker. The molecular weight between cross-links had a significant effect on weight loss after 12 weeks, where samples with M(C) of 1,880 +/- 320 synthesized with a P(PF-co-EG):PEG-DA ratio of 3:1 had a significantly greater mass loss due to degradation than those with M(C) of 1,000 +/- 100 synthesized with a P(PF-co-EG):PEG-DA ratio of 1:1. In contrast, porosity played a minimal role in determining the weight loss. Mechanical testing of the hydrogels under confined compression showed a decrease in compressive modulus over the degradation time for all formulations. In addition, an increase in hydrogel equilibrium water content and pore wall thickness was observed with degradation time, whereas the hydrogel porosity and surface area density remained invariant. The results from microcomputed tomography corroborated with the rest of the measurements and indicated a bulk degradation mechanism of the macroporous hydrogels.

  16. Integration and evaluation of a needle-positioning robot with volumetric microcomputed tomography image guidance for small animal stereotactic interventions.

    Science.gov (United States)

    Waspe, Adam C; McErlain, David D; Pitelka, Vasek; Holdsworth, David W; Lacefield, James C; Fenster, Aaron

    2010-04-01

    Preclinical research protocols often require insertion of needles to specific targets within small animal brains. To target biologically relevant locations in rodent brains more effectively, a robotic device has been developed that is capable of positioning a needle along oblique trajectories through a single burr hole in the skull under volumetric microcomputed tomography (micro-CT) guidance. An x-ray compatible stereotactic frame secures the head throughout the procedure using a bite bar, nose clamp, and ear bars. CT-to-robot registration enables structures identified in the image to be mapped to physical coordinates in the brain. Registration is accomplished by injecting a barium sulfate contrast agent as the robot withdraws the needle from predefined points in a phantom. Registration accuracy is affected by the robot-positioning error and is assessed by measuring the surface registration error for the fiducial and target needle tracks (FRE and TRE). This system was demonstrated in situ by injecting 200 microm tungsten beads into rat brains along oblique trajectories through a single burr hole on the top of the skull under micro-CT image guidance. Postintervention micro-CT images of each skull were registered with preintervention high-field magnetic resonance images of the brain to infer the anatomical locations of the beads. Registration using four fiducial needle tracks and one target track produced a FRE and a TRE of 96 and 210 microm, respectively. Evaluation with tissue-mimicking gelatin phantoms showed that locations could be targeted with a mean error of 154 +/- 113 microm. The integration of a robotic needle-positioning device with volumetric micro-CT image guidance should increase the accuracy and reduce the invasiveness of stereotactic needle interventions in small animals.

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

    Science.gov (United States)

    Christiansen, Blaine A

    2016-12-01

    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.

  18. Fast laboratory-based micro-computed tomography for pore-scale research: Illustrative experiments and perspectives on the future

    Science.gov (United States)

    Bultreys, Tom; Boone, Marijn A.; Boone, Matthieu N.; De Schryver, Thomas; Masschaele, Bert; Van Hoorebeke, Luc; Cnudde, Veerle

    2016-09-01

    Over the past decade, the wide-spread implementation of laboratory-based X-ray micro-computed tomography (micro-CT) scanners has revolutionized both the experimental and numerical research on pore-scale transport in geological materials. The availability of these scanners has opened up the possibility to image a rock's pore space in 3D almost routinely to many researchers. While challenges do persist in this field, we treat the next frontier in laboratory-based micro-CT scanning: in-situ, time-resolved imaging of dynamic processes. Extremely fast (even sub-second) micro-CT imaging has become possible at synchrotron facilities over the last few years, however, the restricted accessibility of synchrotrons limits the amount of experiments which can be performed. The much smaller X-ray flux in laboratory-based systems bounds the time resolution which can be attained at these facilities. Nevertheless, progress is being made to improve the quality of measurements performed on the sub-minute time scale. We illustrate this by presenting cutting-edge pore scale experiments visualizing two-phase flow and solute transport in real-time with a lab-based environmental micro-CT set-up. To outline the current state of this young field and its relevance to pore-scale transport research, we critically examine its current bottlenecks and their possible solutions, both on the hardware and the software level. Further developments in laboratory-based, time-resolved imaging could prove greatly beneficial to our understanding of transport behavior in geological materials and to the improvement of pore-scale modeling by providing valuable validation.

  19. 3D tissue-engineered construct analysis via conventional high-resolution microcomputed tomography without X-ray contrast.

    Science.gov (United States)

    Voronov, Roman S; VanGordon, Samuel B; Shambaugh, Robert L; Papavassiliou, Dimitrios V; Sikavitsas, Vassilios I

    2013-05-01

    As the field of tissue engineering develops, researchers are faced with a large number of degrees of freedom regarding the choice of material, architecture, seeding, and culturing. To evaluate the effectiveness of a tissue-engineered strategy, histology is typically done by physically slicing and staining a construct (crude, time-consuming, and unreliable). However, due to recent advances in high-resolution biomedical imaging, microcomputed tomography (μCT) has arisen as a quick and effective way to evaluate samples, while preserving their structure in the original state. However, a major barrier for using μCT to do histology has been its inability to differentiate between materials with similar X-ray attenuation. Various contrasting strategies (hardware and chemical staining agents) have been proposed to address this problem, but at a cost of additional complexity and limited access. Instead, here we suggest a strategy for how virtual 3D histology in silico can be conducted using conventional μCT, and we provide an illustrative example from bone tissue engineering. The key to our methodology is an implementation of scaffold surface architecture that is ordered in relation to cells and tissue, in concert with straightforward image-processing techniques, to minimize the reliance on contrasting for material segmentation. In the case study reported, μCT was used to image and segment porous poly(lactic acid) nonwoven fiber mesh scaffolds that were seeded dynamically with mesenchymal stem cells and cultured to produce soft tissue and mineralized tissue in a flow perfusion bioreactor using an osteogenic medium. The methodology presented herein paves a new way for tissue engineers to identify and distinguish components of cell/tissue/scaffold constructs to easily and effectively evaluate the tissue-engineering strategies that generate them.

  20. 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

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

    Science.gov (United States)

    2012-01-01

    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 commonly seen in teeth ≤5

  2. 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.

  3. 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.

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

    Science.gov (United States)

    Santos, L. A. N.; Roque-Torres, G. D.; Oliveira, V. F.; Freitas, D. Q.

    2016-01-01

    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. PMID:27293913

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

    Science.gov (United States)

    Santos, L A N; Lopes, L J; Roque-Torres, G D; Oliveira, V F; Freitas, D Q

    2016-01-01

    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.

  6. Micro-Computed Tomography Study of Filling Material Removal from Oval-shaped Canals by Using Rotary, Reciprocating, and Adaptive Motion Systems.

    Science.gov (United States)

    Crozeta, Bruno Monguilhott; Silva-Sousa, Yara Teresinha Correa; Leoni, Graziela Bianchi; Mazzi-Chaves, Jardel Francisco; Fantinato, Thais; Baratto-Filho, Flares; Sousa-Neto, Manoel Damião

    2016-05-01

    This study evaluated filling material removal from distal oval-shaped canals of mandibular molars with rotary, reciprocating, and adaptive motion systems by using micro-computed tomography. After cone-beam computed tomography scanning, 21 teeth were selected, prepared up to a size 40 file, root filled, and divided into 3 groups (n = 7) according to the filling material removal technique: group PTUR, ProTaper Universal Retreatment combined with ProTaper Universal F2, F3, F4, and F5 files; group RP, Reciproc R50 file; and group TFA: TF Adaptive 50.04 files. The specimens were scanned preoperatively and postoperatively to assess filling material removal by using micro-computed tomography imaging, and the percent volume of residual filling material was calculated. The statistical analysis showed the lowest percent volume of residual filling material at the coronal third in all groups (P  .05). In the middle third, group TFA (31.2 ± 10.1) showed lower volume of residual filling material than group RP (52.4 ± 14.1) (P material than group RP (70.6 ± 7.2) (P material from the canals. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  7. Three dimensional imaging of paraffin embedded human lung tissue samples by micro-computed tomography.

    Directory of Open Access Journals (Sweden)

    Anna E Scott

    Full Text Available Understanding the three-dimensional (3-D micro-architecture of lung tissue can provide insights into the pathology of lung disease. Micro computed tomography (µCT has previously been used to elucidate lung 3D histology and morphometry in fixed samples that have been stained with contrast agents or air inflated and dried. However, non-destructive microstructural 3D imaging of formalin-fixed paraffin embedded (FFPE tissues would facilitate retrospective analysis of extensive tissue archives of lung FFPE lung samples with linked clinical data.FFPE human lung tissue samples (n = 4 were scanned using a Nikon metrology µCT scanner. Semi-automatic techniques were used to segment the 3D structure of airways and blood vessels. Airspace size (mean linear intercept, Lm was measured on µCT images and on matched histological sections from the same FFPE samples imaged by light microscopy to validate µCT imaging.The µCT imaging protocol provided contrast between tissue and paraffin in FFPE samples (15 mm x 7 mm. Resolution (voxel size 6.7 µm in the reconstructed images was sufficient for semi-automatic image segmentation of airways and blood vessels as well as quantitative airspace analysis. The scans were also used to scout for regions of interest, enabling time-efficient preparation of conventional histological sections. The Lm measurements from µCT images were not significantly different to those from matched histological sections.We demonstrated how non-destructive imaging of routinely prepared FFPE samples by laboratory µCT can be used to visualize and assess the 3D morphology of the lung including by morphometric analysis.

  8. Predicting mouse vertebra strength with micro-computed tomography-derived finite element analysis.

    Science.gov (United States)

    Nyman, Jeffry S; Uppuganti, Sasidhar; Makowski, Alexander J; Rowland, Barbara J; Merkel, Alyssa R; Sterling, Julie A; Bredbenner, Todd L; Perrien, Daniel S

    2015-01-01

    As in clinical studies, finite element analysis (FEA) developed from computed tomography (CT) images of bones are useful in pre-clinical rodent studies assessing treatment effects on vertebral body (VB) strength. Since strength predictions from microCT-derived FEAs (μFEA) have not been validated against experimental measurements of mouse VB strength, a parametric analysis exploring material and failure definitions was performed to determine whether elastic μFEAs with linear failure criteria could reasonably assess VB strength in two studies, treatment and genetic, with differences in bone volume fraction between the control and the experimental groups. VBs were scanned with a 12-μm voxel size, and voxels were directly converted to 8-node, hexahedral elements. The coefficient of determination or R (2) between predicted VB strength and experimental VB strength, as determined from compression tests, was 62.3% for the treatment study and 85.3% for the genetic study when using a homogenous tissue modulus (E t) of 18 GPa for all elements, a failure volume of 2%, and an equivalent failure strain of 0.007. The difference between prediction and measurement (that is, error) increased when lowering the failure volume to 0.1% or increasing it to 4%. Using inhomogeneous tissue density-specific moduli improved the R (2) between predicted and experimental strength when compared with uniform E t=18 GPa. Also, the optimum failure volume is higher for the inhomogeneous than for the homogeneous material definition. Regardless of model assumptions, μFEA can assess differences in murine VB strength between experimental groups when the expected difference in strength is at least 20%.

  9. Computed tomography-guided biopsy. I. Overview.

    Science.gov (United States)

    Haaga, J R; Reich, N E; Havrilla, T R; Alfidi, R J; Meaney, T F

    1978-03-01

    The authors are preparing a series of communications on CT-guided biopsy procedures to be published in future issues of this journal. The present article, which previously appeared in the Cleveland Clinic Quarterly, is intended to serve as an introduction to the concept of CT-guided biopsies. Because the principles of the biopsy procedure remain the same, we do not believe that a "rewrite" of the previously published article would be required. We hope that by presenting this article and subsequent articles concerning the use of CT-guided biopsies, the reader will acquire an appreciation of the proper role of this exciting new technique in comparison to the available imaging modalities. We believe that as individuals become more experienced with the imaging capabilities of these CT devices, they will want to develop the technique of obtaining biopsy confirmation of the imaging diagnosis.

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

    Science.gov (United States)

    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

  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. 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

  13. Design and validation of a novel bioreactor principle to combine online micro-computed tomography monitoring and mechanical loading in bone tissue engineering

    Science.gov (United States)

    Hagenmüller, Henri; Hitz, Marco; Merkle, Hans P.; Meinel, Lorenz; Müller, Ralph

    2010-01-01

    Mechanical loading plays an important role in bone remodeling in vivo and, therefore, has been suggested as a key parameter in stem cell-based engineering of bone-like tissue in vitro. However, the optimization of loading protocols during stem cell differentiation and subsequent bone-like tissue formation is challenged by multiple input factors, which are difficult to control and validate. These include the variable cellular performance of cells harvested from different patients, nonstandardized culture media components, the choice of the biomaterial forming the scaffold, and its morphology, impacting a broader validity of mechanical stimulation regimens. To standardize the cell culture of bone-like tissue constructs, we suggest the involvement of time-lapsed feedback loops. For this purpose we present a prototype bioreactor that combines online, nondestructive monitoring using micro-computed tomography and direct mechanical loading of three-dimensional tissue engineering constructs. Validation of this system showed displacement steps down to 1 μm and cyclic sinusoidal loadings of up to 10 Hz. Load detection resolution was 0.01 N, and micro-computed tomography data were of high quality. For the first time, the developed bioreactor links time-lapsed, nondestructive, and dynamic imaging with mechanical stimulation, designed for cell culture under sterile conditions. This system is believed to substantially improve today's experimental options to study and optimize osteogenic stem cell culture and differentiation at the interface with mechanical stimulation.

  14. Grapevine petioles are more sensitive to drought induced embolism than stems: evidence from in vivo MRI and microcomputed tomography observations of hydraulic vulnerability segmentation.

    Science.gov (United States)

    Hochberg, Uri; Albuquerque, Caetano; Rachmilevitch, Shimon; Cochard, Herve; David-Schwartz, Rakefet; Brodersen, Craig R; McElrone, Andrew; Windt, Carel W

    2016-09-01

    The 'hydraulic vulnerability segmentation' hypothesis predicts that expendable distal organs are more susceptible to water stress-induced embolism than the main stem of the plant. In the current work, we present the first in vivo visualization of this phenomenon. In two separate experiments, using magnetic resonance imaging or synchrotron-based microcomputed tomography, grapevines (Vitis vinifera) were dehydrated while simultaneously scanning the main stems and petioles for the occurrence of emboli at different xylem pressures (Ψx ). Magnetic resonance imaging revealed that 50% of the conductive xylem area of the petioles was embolized at a Ψx of -1.54 MPa, whereas the stems did not reach similar losses until -1.9 MPa. Microcomputed tomography confirmed these findings, showing that approximately half the vessels in the petioles were embolized at a Ψx of -1.6 MPa, whereas only few were embolized in the stems. Petioles were shown to be more resistant to water stress-induced embolism than previously measured with invasive hydraulic methods. The results provide the first direct evidence for the hydraulic vulnerability segmentation hypothesis and highlight its importance in grapevine responses to severe water stress. Additionally, these data suggest that air entry through the petiole into the stem is unlikely in grapevines during drought.

  15. Design and validation of a novel bioreactor principle to combine online micro-computed tomography monitoring and mechanical loading in bone tissue engineering.

    Science.gov (United States)

    Hagenmüller, Henri; Hitz, Marco; Merkle, Hans P; Meinel, Lorenz; Müller, Ralph

    2010-01-01

    Mechanical loading plays an important role in bone remodeling in vivo and, therefore, has been suggested as a key parameter in stem cell-based engineering of bone-like tissue in vitro. However, the optimization of loading protocols during stem cell differentiation and subsequent bone-like tissue formation is challenged by multiple input factors, which are difficult to control and validate. These include the variable cellular performance of cells harvested from different patients, nonstandardized culture media components, the choice of the biomaterial forming the scaffold, and its morphology, impacting a broader validity of mechanical stimulation regimens. To standardize the cell culture of bone-like tissue constructs, we suggest the involvement of time-lapsed feedback loops. For this purpose we present a prototype bioreactor that combines online, nondestructive monitoring using micro-computed tomography and direct mechanical loading of three-dimensional tissue engineering constructs. Validation of this system showed displacement steps down to 1 microm and cyclic sinusoidal loadings of up to 10 Hz. Load detection resolution was 0.01 N, and micro-computed tomography data were of high quality. For the first time, the developed bioreactor links time-lapsed, nondestructive, and dynamic imaging with mechanical stimulation, designed for cell culture under sterile conditions. This system is believed to substantially improve today's experimental options to study and optimize osteogenic stem cell culture and differentiation at the interface with mechanical stimulation.

  16. Comparative micro-computed tomography evaluation of apical root canal transportation with the use of ProTaper, RaCe and Safesider systems in human teeth.

    Science.gov (United States)

    Ceyhanli, Kadir T; Erdilek, Necdet; Tatar, Ilkan; Cetintav, Bekir

    2014-04-01

    The aim of this study was to compare apical centring ability of nickel titanium (NiTi) ProTaper, RaCe and mainly stainless steel Safesider systems using micro-computed tomography. Thirty freshly extracted mandibular molars with two separate mesial canals and separate foramina were used for the study. Mesial roots were embedded in acrylic resin and instrumented with the ProTaper, RaCe or Safesider systems. Root canal transportation and centring ability of the instruments were evaluated using superimposed micro-computed tomography images of the apical 4 mm of the roots taken at 1 mm intervals. One-way analysis of variance and post hoc Tukey's tests were performed to compare apical transportations. Significant differences were observed between groups at the apical 1, 2 and 3 mm levels (P ProTaper instruments caused more apical root canal transportation than did RaCe instruments at apical 3 mm (P = 0.045). NiTi instrumentation systems showed better centring ability than the mainly stainless steel Safesider system because of the flexible structure of the NiTi alloy.

  17. Microcomputers in Education. Selected Bibliography.

    Science.gov (United States)

    Arsulich, Michael

    The more than 300 recent publications on microcomputers in education which are listed include guides, several books, ERIC documents, and journal articles. Entries are categorized by six primary topic areas: microcomputers; computer literacy; computer assisted instruction (drill and practice, tutorial, and simulation applications); computer managed…

  18. Helical path separation for guided wave tomography

    Energy Technology Data Exchange (ETDEWEB)

    Huthwaite, P.; Seher, M. [Department of Mechanical Engineering, Imperial College, London, SW7 2AZ (United Kingdom)

    2015-03-31

    The pipe wall loss caused by corrosion can be quantified across an area by transmitting guided Lamb waves through the region and measuring the resulting signals. Typically the dispersive relationship for these waves, resulting in the wave velocity being a function of thickness, is exploited which enables the wall thickness to be determined from a velocity reconstruction. The accuracy and quality of this reconstruction is commonly limited by the angle of view available from the transducer arrays. These arrays are often attached as a pair of ring arrays either side of the inspected region, and due to the cyclic nature of the pipe, waves are able to travel in an inifinite number of helical paths between any two transducers. The first arrivals can be separated relatively easily by time gating, but by using just these components the angle of view is strongly restricted. To improve the viewing angle, it is necessary to separate the wavepackets. This paper provides an outline of a separation approach: initially the waves are backpropagated to their source to align the different signals, then a filtering technique is applied to select the desired components. The technique is applied to experimental data and demonstrated to robustly separate the signals.

  19. 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

  20. Retracted: Micro-computed tomography evaluation of apical transportation and centring ability of Reciproc and WaveOne systems in severely curved root canals.

    Science.gov (United States)

    de Meireles, D A; de Brito, T C C A; Marques, A A F; Garrido, A D B; Garcia, L F R; Sponchiado, E C

    2015-08-01

    The following article from International Endodontic Journal, 'Micro-computed tomography evaluation of apical transportation and centring ability of Reciproc and WaveOne systems in severely curved root canals' by D. A. de Meireles, T. C. C. A. de Brito, A. A. F. Marques, A. D. B. Garrido, L. F. R. Garcia & E. C. Sponchiado Jr, published online on 5 February 2015 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the authors, the journal Editor in Chief, Prof. Paul Dummer, and John Wiley & Sons Ltd. The retraction has been agreed due to the use of techniques for crucial measurements in canal shaping and a lack of clarity regarding the measuring methodology. The use of inadequate measuring methodologies makes the findings of the paper invalid.

  1. Efficacy of ProTaper Universal Rotary Retreatment system for gutta-percha removal from oval root canals: a micro-computed tomography study.

    Science.gov (United States)

    Ma, Jingzhi; Al-Ashaw, Ahmed Jawad; Shen, Ya; Gao, Yuan; Yang, Yan; Zhang, Chengfei; Haapasalo, Markus

    2012-11-01

    The aim of this study was to use micro-computed tomography to evaluate the amount of remaining root filling material in oval canals filled by using 2 obturation techniques after retreatment with the ProTaper Universal Retreatment with or without solvent. Forty mandibular incisor teeth with oval canals were prepared to the ProTaper Universal F3 and filled with gutta-percha and iRoot SP sealer by using continuous wave of condensation or cold lateral condensation techniques. The root fillings were removed with the ProTaper Universal Retreatment system, and the canals were prepared further with ProTaper F4. The operating time was measured. Preoperative and postoperative micro-computed tomography imaging was used to assess the percentage of volume of residual filling material in the canals. Remaining filling material was observed in all specimens. The mean volume of remaining material was higher in the continuous wave of condensation groups than in the cold lateral condensation groups, especially in the apical portions of the root canals (P removal and root canal refinement than in the solvent groups (P remove all gutta-percha/sealer from the oval canals. More root filling material was left in the root canals filled by using the continuous wave condensation technique than those filled by using the cold lateral condensation technique after retreatment. In the nonsolvent groups, less time was needed to achieve satisfactory gutta-percha removal and root canal refinement than in the solvent groups. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  2. CT guided diffuse optical tomography for breast cancer imaging

    Science.gov (United States)

    Baikejiang, Reheman; Zhang, Wei; Zhu, Dianwen; Li, Changqing

    2016-03-01

    Diffuse optical tomography (DOT) has attracted attentions in the last two decades due to its intrinsic sensitivity in imaging chromophores of tissues such as blood, water, and lipid. However, DOT has not been clinically accepted yet due to its low spatial resolution caused by strong optical scattering in tissues. Structural guidance provided by an anatomical imaging modality enhances the DOT imaging substantially. Here, we propose a computed tomography (CT) guided multispectral DOT imaging system for breast cancer detection. To validate its feasibility, we have built a prototype DOT imaging system which consists of a laser at wavelengths of 650 and an electron multiplying charge coupled device (EMCCD) camera. We have validated the CT guided DOT reconstruction algorithms with numerical simulations and phantom experiments, in which different imaging setup parameters, such as projection number of measurements, the width of measurement patch, have been investigated. Our results indicate that an EMCCD camera with air cooling is good enough for the transmission mode DOT imaging. We have also found that measurements at six projections are sufficient for DOT to reconstruct the optical targets with 4 times absorption contrast when the CT guidance is applied. Finally, we report our effort and progress on the integration of the multispectral DOT imaging system into a breast CT scanner.

  3. Guided Wave Tomography Based on Full-Waveform Inversion.

    Science.gov (United States)

    Rao, Jing; Ratassepp, Madis; Fan, Zheng

    2016-02-29

    In this paper, a guided wave tomography method based on Full Waveform Inversion (FWI) is developed for accurate and high resolu- tion reconstruction of the remaining wall thickness in isotropic plates. The forward model is computed in the frequency domain by solving a full-wave equation in a two-dimensional acoustic model, accounting for higher order eects such as diractions and multiple scattering. Both numerical simulations and experiments were carried out to obtain the signals of a dispersive guided mode propagating through defects. The inversion was based on local optimization of a waveform mist func- tion between modeled and measured data, and was applied iteratively to discrete frequency components from low to high frequencies. The resulting wave velocity maps were then converted to thickness maps by the dispersion characteristics of selected guided modes. The results suggest that the FWI method is capable to reconstruct the thickness map of a irregularly shaped defect accurately on a 10 mm thick plate with the thickness error within 0.5 mm.

  4. Microcomputer interfacing and applications

    CERN Document Server

    Mustafa, M A

    1990-01-01

    This is the applications guide to interfacing microcomputers. It offers practical non-mathematical solutions to interfacing problems in many applications including data acquisition and control. Emphasis is given to the definition of the objectives of the interface, then comparing possible solutions and producing the best interface for every situation. Dr Mustafa A Mustafa is a senior designer of control equipment and has written many technical articles and papers on the subject of computers and their application to control engineering.

  5. "Speaking" Microcomputer

    Science.gov (United States)

    Mandy, C.; Annerton, J.

    1986-01-01

    Microcomputer system allows blind person to use portable computer and communicate with remote mainframe computer. System prepares data for transmission to mainframe, translates data transmitted from mainframe for its own use, and converts data ordinarily displayed on its video screen into synthesized speech.

  6. "Speaking" Microcomputer

    Science.gov (United States)

    Mandy, C.; Annerton, J.

    1986-01-01

    Microcomputer system allows blind person to use portable computer and communicate with remote mainframe computer. System prepares data for transmission to mainframe, translates data transmitted from mainframe for its own use, and converts data ordinarily displayed on its video screen into synthesized speech.

  7. Evaluation of aggregate microstructures following natural regeneration in bauxite residue as characterized by synchrotron-based X-ray micro-computed tomography.

    Science.gov (United States)

    Zhu, Feng; Liao, Jiaxin; Xue, Shengguo; Hartley, William; Zou, Qi; Wu, Hao

    2016-12-15

    Bauxite residue often has poor physical conditions which impede plant growth. Native plant encroachment on a bauxite residue disposal area in Central China reveals that natural regeneration may improve its physicochemical properties. Residue samples collected from three different disposal ages were assessed to evaluate residue micromorphology and three-dimensional (3D) aggregate microstructure under natural regeneration. The residue aggregates in different disposal ages were divided in two sections: macro-aggregate (2-1mm) and micro-aggregate (0.25-0.05mm). Residue aggregate micromorphology was determined by scanning electron microscope and energy dispersive X-ray spectroscopy, and the residue aggregate microstructure was determined by synchrotron-based X-ray micro-computed tomography (SR-μCT) and image analysis techniques. Natural regeneration may improve residue aggregate stability and form a stable aggregate structure. Calcium content increased whilst sodium content decreased significantly on the surface of residue aggregates. Under natural soil-forming processes bauxite residue porosity, specific surface area, average length of paths, and average tortuosity of paths all significantly increased. This demonstrated that natural regeneration may stimulate the formation of stable aggregate structure in residues. Further understanding should focus on particle interaction forces and agglomeration mechanisms with the addition of external ameliorations. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. 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

  9. Longitudinal Use of Micro-computed Tomography Does Not Alter Microarchitecture of the Proximal Tibia in Sham or Ovariectomized Sprague-Dawley Rats.

    Science.gov (United States)

    Longo, Amanda B; Sacco, Sandra M; Salmon, Phil L; Ward, Wendy E

    2016-06-01

    In vivo micro-computed tomography (μCT) provides the ability to measure longitudinal changes to tibia microarchitecture, but the effect of this radiation is not well understood. The right proximal tibia of Sprague-Dawley rats (n = 12/group) randomized to Sham-control (Sham) or ovariectomy (OVX) surgery at 12 weeks of age was scanned using μCT at 13, 17, 21, and 25 weeks of age, at a resolution of 18 μm and a radiation dose of 603 mGy. The left proximal tibia was scanned only at 25 weeks of age to serve as an internal non-irradiated control. Repeated irradiation did not affect tibia microarchitecture in Sham or OVX groups, although there was an increase in cortical eccentricity (P tibia at 13, 17, 21, and 25 weeks does not cause adverse effects to microarchitecture, regardless of hormone status. This radiation dose can be applied over a typical 3-month study period to comprehensively understand how an intervention alters tibia microarchitecture without confounding effects of radiation.

  10. 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.

  11. Comparative study on submillimeter flaws in stitched T-joint carbon fiber reinforced polymer by infrared thermography, microcomputed tomography, ultrasonic c-scan and microscopic inspection

    Science.gov (United States)

    Zhang, Hai; Hassler, Ulf; Genest, Marc; Fernandes, Henrique; Robitaille, Francois; Ibarra-Castanedo, Clemente; Joncas, Simon; Maldague, Xavier

    2015-10-01

    Stitching is used to reduce dry-core (incomplete infusion of T-joint core) and reinforce T-joint structure. However, it may cause new types of flaws, especially submillimeter flaws. Microscopic inspection, ultrasonic c-scan, pulsed thermography, vibrothermography, and laser spot thermography are used to investigate the internal flaws in a stitched T-joint carbon fiber-reinforced polymer (CFRP) matrix composites. Then, a new microlaser line thermography is proposed. Microcomputed tomography (microCT) is used to validate the infrared results. A comparison between microlaser line thermography and microCT is performed. It was concluded that microlaser line thermography can detect the internal submillimeter defects. However, the depth and size of the defects can affect the detection results. The microporosities with a diameter of less than 54 μm are not detected in the microlaser line thermography results. Microlaser line thermography can detect the microporosity (a diameter of 0.162 mm) from a depth of 90 μm. However, it cannot detect the internal microporosity (a diameter of 0.216 mm) from a depth of 0.18 mm. The potential causes are given. Finally, a comparative study is conducted.

  12. Thermal-stress analysis of ceramic laminate veneer restorations with different incisal preparations using micro-computed tomography-based 3D finite element models.

    Science.gov (United States)

    Celebi, Alper Tunga; Icer, Esra; Eren, Meltem Mert; Baykasoglu, Cengiz; Mugan, Ata; Yildiz, Esra

    2017-11-01

    Main objective of this study is to investigate the thermal behavior of ceramic laminate veneer restorations of the maxillary central incisor with different incisal preparations such as butt joint and palatinal chamfer using finite element method. In addition, it is also aimed to understand the effect of different thermal loads which simulates hot and cold liquid imbibing in the mouth. Three-dimensional solid models of the sound tooth and prepared veneer restorations were obtained using micro-computed tomography images. Each ceramic veneer restoration was made up of ceramic, luting resin cement and adhesive layer which were generated based on the scanned images using computer-aided design software. Our solid model also included the remaining dental tissues such as periodontal ligament and surrounding cortical and spongy bones. Time-dependent linear thermal analyses were carried out to compare temperature changes and stress distributions of the sound and restored tooth models. The liquid is firstly in contact with the crown area where the maximum stresses were obtained. For the restorations, stresses on palatinal surfaces were found larger than buccal surfaces. Through interior tissues, the effect of thermal load diminished and smaller stress distributions were obtained near pulp and root-dentin regions. We found that the palatinal chamfer restoration presents comparatively larger stresses than the butt joint preparation. In addition, cold thermal loading showed larger temperature changes and stress distributions than those of hot thermal loading independent from the restoration technique. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Novel fusion for hybrid optical/microcomputed tomography imaging based on natural light surface reconstruction and iterated closest point

    Science.gov (United States)

    Ning, Nannan; Tian, Jie; Liu, Xia; Deng, Kexin; Wu, Ping; Wang, Bo; Wang, Kun; Ma, Xibo

    2014-02-01

    In mathematics, optical molecular imaging including bioluminescence tomography (BLT), fluorescence tomography (FMT) and Cerenkov luminescence tomography (CLT) are concerned with a similar inverse source problem. They all involve the reconstruction of the 3D location of a single/multiple internal luminescent/fluorescent sources based on 3D surface flux distribution. To achieve that, an accurate fusion between 2D luminescent/fluorescent images and 3D structural images that may be acquired form micro-CT, MRI or beam scanning is extremely critical. However, the absence of a universal method that can effectively convert 2D optical information into 3D makes the accurate fusion challengeable. In this study, to improve the fusion accuracy, a new fusion method for dual-modality tomography (luminescence/fluorescence and micro-CT) based on natural light surface reconstruction (NLSR) and iterated closest point (ICP) was presented. It consisted of Octree structure, exact visual hull from marching cubes and ICP. Different from conventional limited projection methods, it is 360° free-space registration, and utilizes more luminescence/fluorescence distribution information from unlimited multi-orientation 2D optical images. A mouse mimicking phantom (one XPM-2 Phantom Light Source, XENOGEN Corporation) and an in-vivo BALB/C mouse with implanted one luminescent light source were used to evaluate the performance of the new fusion method. Compared with conventional fusion methods, the average error of preset markers was improved by 0.3 and 0.2 pixels from the new method, respectively. After running the same 3D internal light source reconstruction algorithm of the BALB/C mouse, the distance error between the actual and reconstructed internal source was decreased by 0.19 mm.

  14. Tomography for multiconjugate adaptive optics systems using laser guide stars

    Science.gov (United States)

    Gavel, Donald T.

    2004-10-01

    In this paper we present a solution to the MCAO reconstruction problem using multiple laser guide stars and show that it can be interpreted as a form of back-projection tomography. It is shown that a key intermediate step is to determine a minimum-variance estimate of the index variations over the atmospheric volume. We follow the idea of Tokovinin and Viard [JOSA-A, April 2001] in initially formulating the problem in the Fourier domain; we then extend the interpretation to the spatial domain. The former results were limited to the case of infinite aperture and plane wave beacons, and the statistically optimal wavefront solution was given for a single science direction. The new approach is more general and interpretable as tomographic back-projections, which gives rise to algorithms for the finite aperture, cone (laser) beams, and wide-science-field cases. A fortuitous consequence of this analysis is that a "fast" algorithm suitable for real-time implementation has become evident. The reconstruction requires only filtering and the inversion of small (dimension = number of guidestars) matrices. In simulations, we compare results with those of a spatial domain least-square matrix-inversion method.

  15. 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.

  16. Iodine potassium iodide improves the contrast-to-noise ratio of micro-computed tomography images of the human middle ear.

    Science.gov (United States)

    Rohani, S A; Ghomashchi, S; Umoh, J; Holdsworth, D W; Agrawal, S K; Ladak, H M

    2016-12-01

    High-resolution imaging of middle-ear geometry is necessary for finite-element modeling. Although micro-computed tomography (microCT) is widely used because of its ability to image bony structures of the middle ear, it is difficult to visualize soft tissues - including the tympanic membrane and the suspensory ligaments/tendons - because of lack of contrast. The objective of this research is to quantitatively evaluate the efficacy of iodine potassium iodide (IKI) solution as a contrast agent. Six human temporal bones were used in this experiment, which were obtained in right-left pairs, from three cadaveric heads. All bones were fixed using formaldehyde. Three bones (one from each pair) were stained in IKI solution for 2 days, whereas the other three were not stained. Samples were scanned using a microCT system at a resolution of 20 μm. Eight soft tissues in the middle ear were segmented: anterior mallear ligament, incudomallear joint, lateral mallear ligament, posterior incudal ligament, stapedial annular ligament, stapedius muscle, tympanic membrane and tensor tympani muscle. Contrast-to-noise ratios (CNRs) of each soft tissue were calculated for each temporal bone. Combined CNRs of the soft tissues in unstained samples were 6.1 ± 3.0, whereas they were 8.1 ± 2.7 in stained samples. Results from Welch's t-test indicate significant difference between the two groups at a 95% confidence interval. Results for paired t-tests for each of the individual soft tissues also indicated significant improvement of contrast in all tissues after staining. Relatively large soft tissues in the middle ear such as the tympanic membrane and the tensor tympani muscle were impacted by staining more than smaller tissues such as the stapedial annular ligament. The increase in contrast with IKI solution confirms its potential application in automatic segmentation of the middle-ear soft tissues.

  17. 下颌切牙根管解剖显微CT研究%Study of root canal morphology of mandibular incisors by micro-computed tomography in vitro

    Institute of Scientific and Technical Information of China (English)

    朱艳玲; 杨健

    2014-01-01

    Objective:To investigate the anatomy of mandibular incisors using microcomputed tomography(Micro-CT).Methods:62 extracted mandibular incisors were selected from dental clinic and observed by Micro-CT.The anatomy of the teeth was analyzed. Results:83.9% of mandibular incisors had a single canal,72.6% had no accessory canal.The location of the apical foramen varied considerably.The mean distance from the root apex to the major lateral apical foramen was (0.613 ±0.298)mm.Of the canals the bucco-lingual diameter were greater than the mesio-distal diameters and the root bucco-lingual canal tapers were greater than the me-sio-distal.Conclusion:The morphology data of mandibular incisors were obtained using Micro-CT.%目的:采用高分辨率的显微CT观察离体下颌切牙根管解剖结构。方法:收集62颗离体下颌切牙,使用显微CT扫描及三维重建获取每颗牙的解剖数据。结果:83.9%下颌切牙为单根管,72.6%无侧副根管,根尖孔位于旁侧者占56.5%,侧方根尖孔至解剖根尖的距离为(0.613±0.298)mm,下颌切牙根管颊舌向直径及锥度大于近远中向。结论:利用显微CT获得了下颌切牙根管复杂解剖结构的解剖数据。

  18. Micro-computed Tomography Assessment of Dentinal Micro-cracks after Root Canal Preparation with TRUShape and Self-adjusting File Systems.

    Science.gov (United States)

    Zuolo, Mario Luis; De-Deus, Gustavo; Belladonna, Felipe Gonçalves; Silva, Emmanuel João Nogueira Leal da; Lopes, Ricardo Tadeu; Souza, Erick Miranda; Versiani, Marco Aurélio; Zaia, Alexandre Augusto

    2017-04-01

    The aim of the present study was to evaluate the percentage frequency of dentinal micro-cracks observed after root canal preparation with TRUShape and Self-Adjusting File (SAF) systems by means of micro-computed tomography imaging analysis. A conventional full-sequence rotary system (BioRace) and a single-file reciprocation system (Reciproc) were used as reference techniques for comparison because of their known assertive cutting efficiency. Forty anatomically matched mandibular incisors were selected, scanned at a resolution of 14.25 μm, and assigned to 4 experimental groups (n = 10), according to the preparation protocol: TRUShape, SAF, BioRace, and Reciproc systems. After the experimental procedures, the specimens were scanned again, and the registered preoperative and postoperative cross-section images of the roots (n = 70,030) were screened to identify the presence of dentinal micro-cracks. Overall, dentinal defects were observed in 28,790 cross-section images (41.11%). In the TRUShape, SAF, BioRace, and Reciproc groups, dentinal micro-cracks were visualized in 56.47% (n = 9842), 42.38% (n = 7450), 32.90% (n = 5826), and 32.77% (n = 5672) of the slices, respectively. All dentinal defects observed in the postoperative data sets were already present in the corresponding preoperative images. None of the preparation systems induced the formation of new dentinal micro-cracks. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  19. A technique for evaluating bone ingrowth into 3D printed, porous Ti6Al4V implants accurately using X-ray micro-computed tomography and histomorphometry.

    Science.gov (United States)

    Palmquist, Anders; Shah, Furqan A; Emanuelsson, Lena; Omar, Omar; Suska, Felicia

    2017-03-01

    This paper investigates the application of X-ray micro-computed tomography (micro-CT) to accurately evaluate bone formation within 3D printed, porous Ti6Al4V implants manufactured using Electron Beam Melting (EBM), retrieved after six months of healing in sheep femur and tibia. All samples were scanned twice (i.e., before and after resin embedding), using fast, low-resolution scans (Skyscan 1172; Bruker micro-CT, Kontich, Belgium), and were analysed by 2D and 3D morphometry. The main questions posed were: (i) Can low resolution, fast scans provide morphometric data of bone formed inside (and around) metal implants with a complex, open-pore architecture?, (ii) Can micro-CT be used to accurately quantify both the bone area (BA) and bone-implant contact (BIC)?, (iii) What degree of error is introduced in the quantitative data by varying the threshold values?, and (iv) Does resin embedding influence the accuracy of the analysis? To validate the accuracy of micro-CT measurements, each data set was correlated with a corresponding centrally cut histological section. The results show that quantitative histomorphometry corresponds strongly with 3D measurements made by micro-CT, where a high correlation exists between the two techniques for bone area/volume measurements around and inside the porous network. On the contrary, the direct bone-implant contact is challenging to estimate accurately or reproducibly. Large errors may be introduced in micro-CT measurements when segmentation is performed without calibrating the data set against a corresponding histological section. Generally, the bone area measurement is strongly influenced by the lower threshold limit, while the upper threshold limit has little or no effect. Resin embedding does not compromise the accuracy of micro-CT measurements, although there is a change in the contrast distributions and optimisation of the threshold ranges is required. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  2. Use of micro-computed tomography to evaluate the effects of exercise on preventing the degeneration of articular cartilage in tail-suspended rats

    Science.gov (United States)

    Luan, Hui-Qin; Sun, Lian-Wen; Huang, Yun-Fei; Wu, Xin-tong; Niu, Haijun; Liu, Hong; Fan, Yu-Bo

    2015-07-01

    Space flight has been shown to induce bone loss and muscle atrophy, which could initiate the degeneration of articular cartilage. Countermeasures to prevent bone loss and muscle atrophy have been explored, but few spaceflight or ground-based studies have focused on the effects on cartilage degeneration. In this study, we investigated the effects of exercise on articular cartilage deterioration in tail-suspended rats. Thirty-two female Sprague-Dawley rats were randomly divided into four groups (n = 8 in each): tail suspension (TS), tail suspension plus passive motion (TSP), tail suspension plus active exercise (TSA), and control (CON) groups. In the TS, TSP, and TSA groups, the rat hindlimbs were unloaded for 21 days by tail suspension. Next, the cartilage thickness and volume, and the attenuation coefficient of the distal femur were evaluated by micro-computed tomography (μCT). Histological analysis was used to assess the surface integrity of the cartilage, cartilage thickness, and chondrocytes. The results showed that: (1) the cartilage thickness on the distal femur was significantly lower in the TS and TSP groups compared with the CON and TSA groups; (2) the cartilage volume in the TS group was significantly lower compared with the CON, TSA, and TSP groups; and (3) histomorphology showed that the chondrocytes formed clusters where the degree of matrix staining was lower in the TS and TSP groups. There were no significant differences between any of these parameters in the CON and TSA groups. The cartilage thickness measurements obtained by μCT and histomorphology correlated well. In general, tail suspension could induce articular cartilage degeneration, but active exercise was effective in preventing this degeneration in tail-suspended rats.

  3. A micro-computed tomography assessment of the efficacy of rotary and reciprocating techniques for filling material removal in root canal retreatment.

    Science.gov (United States)

    Monguilhott Crozeta, Bruno; Damião de Sousa-Neto, Manoel; Bianchi Leoni, Graziela; Francisco Mazzi-Chaves, Jardel; Terezinha Corrêa Silva-Sousa, Yara; Baratto-Filho, Flares

    2016-11-01

    The aim of this study was to compare the efficacy of rotary and reciprocating techniques for removing filling material from root canals, using micro-computed tomography (micro-CT) imaging. The distal root canals of 42 human mandibular molars were instrumented with hand files up to size 40 according to a step-down technique and obturated with gutta-percha and an epoxy resin-based sealer using Tagger's hybrid technique. Teeth were divided into six groups (n = 7) according to the instruments used for removal of filling material: group PTUR (Protaper Universal Retreatment), group W40 (WaveOne 40.08), group R40 (Reciproc 40.06), group R50 (Reciproc 50.05), group W25/W40 (WaveOne 25.08/40.08), and group R25/R40/R50 (Reciproc 25.08/40.06/50.05). Teeth were scanned with a micro-CT device before and after use of the instruments to calculate the percentage of remaining filling material. Data were compared using one-way ANOVA and Fisher's LSD test at 5 % significance level. The mean percentage of remaining filling material was significantly lower when canals were retreated with the set of instruments R25/R40/R50 and single instruments W40 and R50 compared with the set of instruments W25/W40 (P removed the root fillings completely. PTUR instruments performed equally effective regarding filling removal compared with W40, R40, R50, W25/W40, and R25/R40/R50. For WaveOne, the use of a single instrument (size 40, taper 0.08) was more effective in removing filling material, while for Reciproc showed similar cleaning ability using single instrument or combination of instruments. The results of this in vitro study provide consistent information on filling material removal capacity of mechanized systems during retreatment at the different root canal thirds.

  4. Sine systemate chaos? A versatile tool for earthworm taxonomy: non-destructive imaging of freshly fixed and museum specimens using micro-computed tomography.

    Science.gov (United States)

    Fernández, Rosa; Kvist, Sebastian; Lenihan, Jennifer; Giribet, Gonzalo; Ziegler, Alexander

    2014-01-01

    In spite of the high relevance of lumbricid earthworms ('Oligochaeta': Lumbricidae) for soil structure and functioning, the taxonomy of this group of terrestrial invertebrates remains in a quasi-chaotic state. Earthworm taxonomy traditionally relies on the interpretation of external and internal morphological characters, but the acquisition of these data is often hampered by tedious dissections or restricted access to valuable and rare museum specimens. The present state of affairs, in conjunction with the difficulty of establishing primary homologies for multiple morphological features, has led to an almost unrivaled instability in the taxonomy and systematics of certain earthworm groups, including Lumbricidae. As a potential remedy, we apply for the first time a non-destructive imaging technique to lumbricids and explore the future application of this approach to earthworm taxonomy. High-resolution micro-computed tomography (μCT) scanning of freshly fixed and museum specimens was carried out using two cosmopolitan species, Aporrectodea caliginosa and A. trapezoides. By combining two-dimensional and three-dimensional dataset visualization techniques, we demonstrate that the morphological features commonly used in earthworm taxonomy can now be analyzed without the need for dissection, whether freshly fixed or museum specimens collected more than 60 years ago are studied. Our analyses show that μCT in combination with soft tissue staining can be successfully applied to lumbricid earthworms. An extension of the approach to other families is poised to strengthen earthworm taxonomy by providing a versatile tool to resolve the taxonomic chaos currently present in this ecologically important, but taxonomically neglected group of terrestrial invertebrates.

  5. Automated 3D-2D registration of X-ray microcomputed tomography with histological sections for dental implants in bone using chamfer matching and simulated annealing.

    Science.gov (United States)

    Becker, Kathrin; Stauber, Martin; Schwarz, Frank; Beißbarth, Tim

    2015-09-01

    We propose a novel 3D-2D registration approach for micro-computed tomography (μCT) and histology (HI), constructed for dental implant biopsies, that finds the position and normal vector of the oblique slice from μCT that corresponds to HI. During image pre-processing, the implants and the bone tissue are segmented using a combination of thresholding, morphological filters and component labeling. After this, chamfer matching is employed to register the implant edges and fine registration of the bone tissues is achieved using simulated annealing. The method was tested on n=10 biopsies, obtained at 20 weeks after non-submerged healing in the canine mandible. The specimens were scanned with μCT 100 and processed for hard tissue sectioning. After registration, we assessed the agreement of bone to implant contact (BIC) using automated and manual measurements. Statistical analysis was conducted to test the agreement of the BIC measurements in the registered samples. Registration was successful for all specimens and agreement of the respective binary images was high (median: 0.90, 1.-3. Qu.: 0.89-0.91). Direct comparison of BIC yielded that automated (median 0.82, 1.-3. Qu.: 0.75-0.85) and manual (median 0.61, 1.-3. Qu.: 0.52-0.67) measures from μCT were significant positively correlated with HI (median 0.65, 1.-3. Qu.: 0.59-0.72) between μCT and HI groups (manual: R(2)=0.87, automated: R(2)=0.75, p<0.001). The results show that this method yields promising results and that μCT may become a valid alternative to assess osseointegration in three dimensions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Quantifying floral shape variation in 3D using microcomputed tomography: a case study of a hybrid line between actinomorphic and zygomorphic flowers

    Directory of Open Access Journals (Sweden)

    Chun-Neng eWang

    2015-09-01

    Full Text Available The quantification of floral shape variations is difficult because flower structures are both diverse and complex. Traditionally, floral shape variations are quantified using the qualitative and linear measurements of two-dimensional (2D images. The 2D images cannot adequately describe flower structures, and thus lead to unsatisfactory discrimination of the flower shape. This study aimed to acquire three-dimensional (3D images by using microcomputed tomography (μCT and to examine the floral shape variations by using geometric morphometrics (GM. To demonstrate the advantages of the 3D-µCT-GM approach, we applied the approach to a second-generation population of florist’s gloxinia (Sinningia speciosa crossed from parents of zygomorphic and actinomorphic flowers. The flowers in the population considerably vary in size and shape, thereby served as good materials to test the applicability of the proposed phenotyping approach. Procedures were developed to acquire 3D volumetric flower images using a μCT scanner, to segment the flower regions from the background, and to select homologous characteristic points (i.e., landmarks from the flower images for the subsequent GM analysis. The procedures identified 95 landmarks for each flower and thus improved the capability of describing and illustrating the flower shapes, compared with typically lower number of landmarks in 2D analyses. The GM analysis demonstrated that flower opening and dorsoventral symmetry were the principal shape variations of the flowers. The degrees of flower opening and corolla asymmetry were then subsequently quantified directly from the 3D flower images. The 3D-µCT-GM approach revealed shape variations that could not be identified using typical 2D approaches and accurately quantified the flower traits that presented a challenge in 2D images. The approach opens new avenues to investigate floral shape variations.

  7. Comparison of bioimpedance spectroscopy and X-Ray micro-computed tomography for total fat volume measurement in mice.

    Science.gov (United States)

    Aubertin, Gaelle; Sayeh, Amira; Dillenseger, Jean-Philippe; Ayme-Dietrich, Estelle; Choquet, Philippe; Niederhoffer, Nathalie

    2017-01-01

    Obesity and the metabolic syndrome are two pathologies whose prevalence are in a constant increase. Evaluation of the total fat mass but also of the distribution between visceral and subcutaneous adipose tissue are important factors while assessing the pathophysiology of these two pathologies. Computed tomography (CT) and bioimpedance (BIS) are the translational methods the most frequently used in human beings as well as in rodent models in longitudinal studies on adiposity and obesity. Surprisingly, no direct comparison of micro-CT and BIS was reported yet in mice. Therefore, the present study was carried out to evaluate and compare the accuracy and the uncertainty of measurement of micro-CT and BIS in this species. The proportion of fat mass was measured with BIS, micro-CT and direct post-mortem tissue weight, and correlations between the data were established to evaluate the accuracy of the methods but also the uncertainty of BIS and micro-CT. There were significant correlations between weights of fat tissues on scale and proportion of total fat mass determined by BIS or micro-CT (r = 0.81 and 0.86 respectively) but both methods overestimated the total fat mass, especially in the smallest animals; overestimation of fat mass was amplified with BIS compared to micro-CT. In addition BIS and micro-CT were highly correlated (r = 0.94). Test-test reliability showed a greater variability of the BIS with respect to the micro-CT (coefficient of variation = 17.2 vs 5.6% respectively). Hence, as far as subtle differences between groups or changes within one group are awaited, micro-CT may appear as the most reliable method for determination of fat mass in mice. Micro-CT, unlike BIS, will also allow to qualitatively and quantitatively differentiate between subcutaneous and visceral adipose tissues, which is of major importance in studies on adiposity and its complications.

  8. 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.

  9. Local electrode atom probe tomography a user's guide

    CERN Document Server

    Larson, David J; Ulfig, Robert M; Geiser, Brian P; Kelly, Thomas F; Humphreys, Professor Sir Colin J

    2014-01-01

    The first single-source reference to all the major features of LEAP tomography, this volume includes a wealth of practical tips and covers all four core aspects of a LEAP tomography experiment from start to finish, as well as the software methods employed.

  10. Real-time-guided bone regeneration around standardized critical size calvarial defects using bone marrow-derived mesenchymal stem cells and collagen membrane with and without using tricalcium phosphate: an in vivo microcomputed tomographic and histologic experiment in rats

    Institute of Scientific and Technical Information of China (English)

    Khalid Al-Hezaimi; Sundar Ramalingam; Mansour Al-Askar; Aws S ArRejaie; Nasser Nooh; Fawad Jawad; Abdullah Aldahmash; Muhammad Atteya; Cun-Yu Wang

    2016-01-01

    The aimof the present real time in vivo micro-computed tomography (mCT) and histologic experiment was to assess the efficacy of guided bone regeneration (GBR) around standardized calvarial critical size defects (CSD) using bone marrow-derived mesenchymal stem cells (BMSCs), and collagen membrane (CM) with and without tricalcium phosphate (TCP) graft material. In the calvaria of nine female Sprague-Dawley rats, full-thickness CSD (diameter 4.6 mm) were created under general anesthesia. Treatment-wise, rats were divided into three groups. In group 1, CSD was covered with a resorbable CM; in group 2, BMSCs were filled in CSD and covered with CM; and in group 3, TCP soaked in BMSCs was placed in CSD and covered with CM. All defects were closed using resorbable sutures. Bone volume and bone mineral density of newly formed bone (NFB) and remaining TCP particles and rate of new bone formation was determined at baseline, 2, 4, 6, and 10 weeks using in vivo mCT. At the 10th week, the rats were killed and calvarial segments were assessed histologically. The results showed that the hardness ofNFBwas similar to that of the native bone in groups 1 and 2 as compared to theNFB in group 3. Likewise, values for the modulus of elasticity were also significantly higher in group 3 compared to groups 1 and 2. This suggests that TCP when used in combination with BMSCs and without CM was unable to form bone of significant strength that could possibly provide mechanical “lock” between the natural bone and NFB. The use of BMSCs as adjuncts to conventional GBR initiated new bone formation as early as 2 weeks of treatment compared to when GBR is attempted without adjunct BMSC therapy.

  11. Rescuing Perishable Neuroanatomical Information from a Threatened Biodiversity Hotspot: Remote Field Methods for Brain Tissue Preservation Validated by Cytoarchitectonic Analysis, Immunohistochemistry, and X-Ray Microcomputed Tomography.

    Directory of Open Access Journals (Sweden)

    Daniel F Hughes

    Full Text Available Biodiversity hotspots, which harbor more endemic species than elsewhere on Earth, are increasingly threatened. There is a need to accelerate collection efforts in these regions before threatened or endangered species become extinct. The diverse geographical, ecological, genetic, morphological, and behavioral data generated from the on-site collection of an individual specimen are useful for many scientific purposes. However, traditional methods for specimen preparation in the field do not permit researchers to retrieve neuroanatomical data, disregarding potentially useful data for increasing our understanding of brain diversity. These data have helped clarify brain evolution, deciphered relationships between structure and function, and revealed constraints and selective pressures that provide context about the evolution of complex behavior. Here, we report our field-testing of two commonly used laboratory-based techniques for brain preservation while on a collecting expedition in the Congo Basin and Albertine Rift, two poorly known regions associated with the Eastern Afromontane biodiversity hotspot. First, we found that transcardial perfusion fixation and long-term brain storage, conducted in remote field conditions with no access to cold storage laboratory equipment, had no observable impact on cytoarchitectural features of lizard brain tissue when compared to lizard brain tissue processed under laboratory conditions. Second, field-perfused brain tissue subjected to prolonged post-fixation remained readily compatible with subsequent immunohistochemical detection of neural antigens, with immunostaining that was comparable to that of laboratory-perfused brain tissue. Third, immersion-fixation of lizard brains, prepared under identical environmental conditions, was readily compatible with subsequent iodine-enhanced X-ray microcomputed tomography, which facilitated the non-destructive imaging of the intact brain within its skull. In summary, we

  12. Comparison of Synchrotron Radiation-based Propagation Phase Contrast Imaging and Conventional Micro-computed Tomography for Assessing Intervertebral Discs and Endplates in a Murine Model.

    Science.gov (United States)

    Hu, Jianzhong; Ni, Shuangfei; Cao, Yong; Wang, Xiaokai; Liao, Shenghui; Lu, Hongbin

    2017-08-01

    The synchrotron radiation-based micro-computed tomography (SRμCT) and micro-CT (μCT) were applied to comparatively assess the intervertebral disc (IVD) and endplate (EP). To explore a new approach to evaluate the detailed structure of the IVD and EP during maturation and aging in a murine model. Till date, methods to observe the morphological changes in the IVD and EP from rodents have been relatively limited. SRμCT has been recognized as a potential way to visualize the structures containing sclerous and soft tissue. Our study focused on comparing the capacity of SRμCT and μCT in evaluating the detailed structure of the IVD and EP. Both SRμCT and μCT were performed to depict the structure of spinal tissue from 4-month-old mice. Then, the imaging quality was evaluated in the three-dimensional (3D) reconstructed model. Further, the changes in the EP and IVD during the maturation and aging process were assessed morphologically and quantitatively using SRμCT. The 3D reconstructed model of the EP from both μCT and SRμCT provided detailed information on its inner structure. However, the IVD was only depicted using SRμCT. Multi-angle observations of the 3D structure of EP and IVD from mice of different ages (15 days, 2 months, 4 months, and 18 months) were dynamically performed by SRμCT. Quantitative evaluations indicated that the total volume of EP and IVD, the average height of IVD and the canal-total volume ratio of EP increased from 15-day-old mice to 4-month-old mice and decreased in 18-month-old mice. The EP and IVD were clearly visualized using SRμCT. Compared with μCT, SRμCT provided a better ultrahigh resolution image of soft tissue and hard tissue simultaneously, which makes it a promising approach for the noninvasive study of disc degeneration. N /A.

  13. Efficacy of ProTaper NEXT Compared with Reciproc in Removing Obturation Material from Severely Curved Root Canals: A Micro-Computed Tomography Study.

    Science.gov (United States)

    Nevares, Giselle; de Albuquerque, Diana S; Freire, Laila G; Romeiro, Kaline; Fogel, Howard M; Dos Santos, Marcelo; Cunha, Rodrigo S

    2016-05-01

    The aim of this study was to compare the remaining root canal obturation, volume of dentin removed, and apical transportation after retreatment of severely curved root canals by using Reciproc (REC) or ProTaper NEXT (PTN) systems. Twenty-eight mesial canals of mandibular molars were instrumented and then obturated with gutta-percha and sealer and allocated into 2 balanced groups (n = 14), the REC group (R25 file) and the PTN group (X3 and X2 files). Micro-computed tomography analysis was performed to assess the percentage of residual obturation material, the amount of dentin removed, and apical transportation. The effective time for the removal of obturation and procedural errors were recorded. Obturation was effectively removed from the root canal in the REC and PTN groups (P ≤ .001), and the percentages of remaining obturation material were similar between both groups (84.8% PTN vs 86.5% REC) (P > .05). The amount of dentin removed (3.17 ± 2.64 mm(3) PTN versus 3.50 ± 2.82 mm(3) REC), apical transportation (at 1 mm: 0.096 ± 0.189 mm PTN versus 0.093 ± 0.186 mm REC; at 3 mm: 0.059 ± 0.069 mm PTN versus 0.082 ± 0.080 mm REC; at 5 mm: 0.097 ± 0.093 mm PTN versus 0.133 ± 0.138 mm REC), and the working time (269.69 ± 19.25 seconds PTN versus 268.62 ± 16.37 seconds REC) were also similar in both groups (P > .05). One file fractured in the REC group. Both systems were equally effective in the removal of obturation from severely curved canals and can be used for retreatment. Neither system could completely remove the obturation material; therefore, additional techniques are needed to improve cleaning of the root canal. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  14. Micro-computed tomography evaluation of the removal of calcium hydroxide medicament from C-shaped root canals of mandibular second molars.

    Science.gov (United States)

    Ma, J Z; Shen, Y; Al-Ashaw, A J; Khaleel, H Y; Yang, Y; Wang, Z J; Peng, B; Haapasalo, M

    2015-04-01

    To use micro-computed tomography (μ-CT) to evaluate the amount of calcium hydroxide [Ca(OH)2 ] remaining in the C-shaped root canals of mandibular second molars after attempting to remove it with passive ultrasonic and sonic irrigation. Thirty mandibular second molars, 15 in C1 and 15 in C2 configurations as first identified by μ-CT, were divided into three groups (five C1 and five C2 in each group) for the three irrigation methods. All teeth were prepared to ProTaper Universal F2 and filled with Ca(OH)2 paste. The Ca(OH)2 was removed with F2 files and irrigation without agitation or with agitation using either EndoActivator or ultrasonics. μ-CT was used to measure the initial amount of Ca(OH)2 present. After removal of Ca(OH)2, μ-CT imaging was used to assess the percentage of volume of residual Ca(OH)2 in the canal. Data were analysed using one-way anova test. There was no significant difference in the mean volume of the root canal systems after instrumentation amongst the three groups. The three irrigation techniques left 2-17% of Ca(OH)2 in the root canals after removal. The mean volume of the remaining Ca(OH)2 was higher in the group without agitation than in the groups with sonic or ultrasonic agitation (P < 0.05). In the apical third, 68% of the canal space remained occupied by Ca(OH)2 when no agitation was used, whereas 28% and 31% remained filled by Ca(OH)2 in the EndoActivator and ultrasonic groups, respectively. There was no significant difference in the amount of residual Ca(OH)2 between the EndoActivator and ultrasonic groups. The proportion of remaining Ca(OH)2 in the apical canals was higher than in the middle and coronal canals in all groups (P < 0.05). A considerable proportion of the apical canal space remained filled with Ca(OH)2 in the C-shaped root canals after instrumentation and conventional needle irrigation. Although combining rotary instrumentation and irrigation with sonic or ultrasonic agitation reduced the amount of residual Ca

  15. Three-Dimensional Quantification of Calcium Salt-Composite Resorption (CSC) In Vitro by Micro-computed Tomography (Micro-CT)

    Science.gov (United States)

    Winkler, T.; Dai, X. Y.; Mielke, G.; Vogt, S.; Buechner, H.; Schantz, J. T.; Harder, Y.; Machens, H. G.; Morlock, M. M.; Schilling, A. F.

    2014-04-01

    The commonly applied cell-based, two-dimensional (2D) in vitro resorption assays for biomaterials are limited in a variety of cases, including high initial roughness of material surface, uncontrollable solubilization (or resorption) of the entire material surface, or complex three-dimensional (3D) structure of the bioactive material itself. All these make the accurate assessment and successful selection of the optimal bone substitute material difficult. In vivo, micro-computed tomography (micro-CT) has been widely applied for the analysis of bone physiology and pathology, as well as for the 3D analysis of scaffolds for bone tissue engineering. In this study, we show that micro-CT can also be applied for the in vitro analysis of osteoclast-mediated resorption of biomaterials. For our experiments, we chose a calcium salt-composite (composite of calcium sulphate (CSC), calcium carbonate, glycerin-1,2,3-tripalmiate), which evades common 2D in vitro resorption analysis as a result of its high surface roughness and material composition. Human osteoclasts were differentiated from precursor cells on the surface of the material for 28 days. Cells were analyzed for expression of tartrate-resistant acid phosphatase 5b (TRAP5b), multinuclearity, and size. Volumetric analysis of resorption was performed by micro-CT. Multinucleated osteoclasts developed on the surface of the material. TRAP5b expression of the cells on CSC was comparable with TRAP5b expression of cells cultivated on dentin for the first 3 weeks of culture. At day 28, TRAP5b expression, cell number, and size of the TRAP+ cells were reduced on the CSC when compared with cells on dentin. Volumetric anaylsis by micro-CT showed a strong cellular effect on resorption of CSC. We consider micro-CT to be a promising technique for 3D quantification of cell-based resorption that will allow the study of cellular resorption of materials in vitro, which were up to now confined to animal experimental analysis.

  16. Rescuing Perishable Neuroanatomical Information from a Threatened Biodiversity Hotspot: Remote Field Methods for Brain Tissue Preservation Validated by Cytoarchitectonic Analysis, Immunohistochemistry, and X-Ray Microcomputed Tomography.

    Science.gov (United States)

    Hughes, Daniel F; Walker, Ellen M; Gignac, Paul M; Martinez, Anais; Negishi, Kenichiro; Lieb, Carl S; Greenbaum, Eli; Khan, Arshad M

    2016-01-01

    Biodiversity hotspots, which harbor more endemic species than elsewhere on Earth, are increasingly threatened. There is a need to accelerate collection efforts in these regions before threatened or endangered species become extinct. The diverse geographical, ecological, genetic, morphological, and behavioral data generated from the on-site collection of an individual specimen are useful for many scientific purposes. However, traditional methods for specimen preparation in the field do not permit researchers to retrieve neuroanatomical data, disregarding potentially useful data for increasing our understanding of brain diversity. These data have helped clarify brain evolution, deciphered relationships between structure and function, and revealed constraints and selective pressures that provide context about the evolution of complex behavior. Here, we report our field-testing of two commonly used laboratory-based techniques for brain preservation while on a collecting expedition in the Congo Basin and Albertine Rift, two poorly known regions associated with the Eastern Afromontane biodiversity hotspot. First, we found that transcardial perfusion fixation and long-term brain storage, conducted in remote field conditions with no access to cold storage laboratory equipment, had no observable impact on cytoarchitectural features of lizard brain tissue when compared to lizard brain tissue processed under laboratory conditions. Second, field-perfused brain tissue subjected to prolonged post-fixation remained readily compatible with subsequent immunohistochemical detection of neural antigens, with immunostaining that was comparable to that of laboratory-perfused brain tissue. Third, immersion-fixation of lizard brains, prepared under identical environmental conditions, was readily compatible with subsequent iodine-enhanced X-ray microcomputed tomography, which facilitated the non-destructive imaging of the intact brain within its skull. In summary, we have validated

  17. 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.

  18. Correlation analysis of cortical geometry of tibia and humerus of white leghorns using clinical quantitative computed tomography and microcomputed tomography scans1.

    Science.gov (United States)

    Regmi, P; Cox, A G; Robison, C I; Karcher, D M

    2017-03-24

    Peripheral quantitative computed tomography (QCT) has been used in poultry bone research in recent years to analyze cortical and cross-sectional geometry. For QCT to be used as a standard research tool for analysis of bones of laying hens (cortical thickness correlate the cortical parameters measured using clinical CT scans with the measurements from micro-CT, the current gold standard. A total of 15 tibiae and 14 humeri of Lohmann White hens was scanned using clinical CT and micro-CT. Reconstruction of the scans generated images with final voxel resolution of 195 μm for clinical CT scans and 46 μm for micro-CT scans. Cortical and total area were measured using MIMICS® software at proximal, middle, and distal locations of 20 mm sections of humerus diaphysis and 30 mm sections of tibia diaphysis. The total area for proximal and middle locations as well as proximal cortical area measurements for humeri produced strong correlation coefficients (R ≥ 0.70). Moderate strength correlation coefficients (R = 0.40 to 0.60) in humeri were seen in middle and distal cortical areas. Distal total area in humeri displayed a weak correlation coefficient (R ≤ 0.3; P = 0.25). Overall, tibiae demonstrated a weaker correlation. Proximal and middle cortical areas indicated moderate correlation coefficients (R = 0.40 to 0.60), while proximal and middle total areas accompanied by distal cortical and total area displayed weak correlation coefficients (R ≤ 0.3). Only the middle cortical area measurement for tibiae was significant (P = 0.03). These results indicate stronger correlation for humeri measurements among the scans than tibia. Overall, cross-sectional area measurements were only low to moderately correlated between clinical and micro-CT scans. © 2017 Poultry Science Association Inc.

  19. MICRO-VERS. Micro-computer Software for the Vocational Education Reporting System. User's Guide and Reference Manual. Version 3.1. Apple II.

    Science.gov (United States)

    Illinois State Board of Education, Springfield. Dept. of Adult, Vocational and Technical Education.

    This manual is intended to accompany a software system for the Apple II microcomputer that is designed to aid local districts in completing vocational education enrollment claims and Vocational Education Data System (VEDS) reports. Part I, Introduction, gives a brief overview of the Microcomputer Vocational Education Reporting System (MICRO-VERS),…

  20. An Evaluator's Guide to Using DB MASTER: A Microcomputer Based File Management Program. Research on Evaluation Program, Paper and Report Series No. 91.

    Science.gov (United States)

    Gray, Peter J.

    Ways a microcomputer can be used to establish and maintain an evaluation database and types of data management features possible on a microcomputer are described in this report, which contains step-by-step procedures and numerous examples for establishing a database, manipulating data, and designing and printing reports. Following a brief…

  1. Dual-energy X-ray absorptiometry, peripheral quantitative computed tomography, and micro-computed tomography techniques are discordant for bone density and geometry measurements in the guinea pig.

    Science.gov (United States)

    Mak, Ivy L; DeGuire, Jason R; Lavery, Paula; Agellon, Sherry; Weiler, Hope A

    2016-05-01

    This study aims to examine agreement among bone mineral content (BMC) and density (BMD) estimates obtained using dual-energy X-ray absorptiometry (DXA), peripheral quantitative computed tomography (pQCT), and micro-computed tomography (μCT) against high-resolution μCT and bone ash of the guinea pig femur. Middle-aged (n = 40, 86 weeks) male guinea pigs underwent in vivo followed by ex vivo DXA (Hologic QDR 4500A) scanning for intact and excised femur BMC and areal density. To assess bone architecture and strength, excised femurs were scanned on pQCT (Stratec XCT 2000L) as well as on two μCT scanners (LaTheta LCT-200; Skyscan 1174), followed by three-point bending test. Reproducibility was determined using triplicate scans; and agreement assessed using Bland-Altman plots with reference methods being high-resolution μCT (Skyscan) for BMD and bone ashing for BMC. All techniques showed satisfactory ex vivo precision (CV 0.05-4.3 %). However, bias compared to the reference method was highest (207.5 %) in trabecular bone volume fraction (BV/TV) measured by LaTheta, and unacceptable in most total femur and cortical bone measurements. Volumetric BMD (vBMD) and BV/TV derived by LaTheta and pQCT at the distal metaphysis were biased from the Skyscan by an average of 49.3 and 207.5 %, respectively. Variability of vBMD, BV/TV and cross-sectional area at the diaphysis ranged from -5.5 to 30.8 %. LaTheta best quantified total femur BMC with an upper bias of 3.3 %. The observed differences among imaging techniques can be attributable to inherent dissimilarity in construction design, calibration, segmentation and scanning resolution used. These bone imaging tools are precise but are not comparable, at least when assessing guinea pig bones.

  2. Comparison tomography relocation hypocenter grid search and guided grid search method in Java island

    Science.gov (United States)

    Nurdian, S. W.; Adu, N.; Palupi, I. R.; Raharjo, W.

    2016-11-01

    The main data in this research is earthquake data recorded from 1952 to 2012 with 9162 P wave and 2426 events are recorded by 30 stations located around Java island. Relocation hypocenter processed using grid search and guidded grid search method. Then the result of relocation hypocenter become input for tomography pseudo bending inversion process. It can be used to identification the velocity distribution in subsurface. The result of relocation hypocenter by grid search and guided grid search method after tomography process shown in locally and globally. In locally area grid search method result is better than guided grid search according to geological reseach area. But in globally area the result of guided grid search method is better for a broad area because the velocity variation is more diverse than the other one and in accordance with local geological research conditions.

  3. Feasibility of Computed Tomography-Guided Methods for Spatial Normalization of Dopamine Transporter Positron Emission Tomography Image.

    Directory of Open Access Journals (Sweden)

    Jin Su Kim

    Full Text Available Spatial normalization is a prerequisite step for analyzing positron emission tomography (PET images both by using volume-of-interest (VOI template and voxel-based analysis. Magnetic resonance (MR or ligand-specific PET templates are currently used for spatial normalization of PET images. We used computed tomography (CT images acquired with PET/CT scanner for the spatial normalization for [18F]-N-3-fluoropropyl-2-betacarboxymethoxy-3-beta-(4-iodophenyl nortropane (FP-CIT PET images and compared target-to-cerebellar standardized uptake value ratio (SUVR values with those obtained from MR- or PET-guided spatial normalization method in healthy controls and patients with Parkinson's disease (PD.We included 71 healthy controls and 56 patients with PD who underwent [18F]-FP-CIT PET scans with a PET/CT scanner and T1-weighted MR scans. Spatial normalization of MR images was done with a conventional spatial normalization tool (cvMR and with DARTEL toolbox (dtMR in statistical parametric mapping software. The CT images were modified in two ways, skull-stripping (ssCT and intensity transformation (itCT. We normalized PET images with cvMR-, dtMR-, ssCT-, itCT-, and PET-guided methods by using specific templates for each modality and measured striatal SUVR with a VOI template. The SUVR values measured with FreeSurfer-generated VOIs (FSVOI overlaid on original PET images were also used as a gold standard for comparison.The SUVR values derived from all four structure-guided spatial normalization methods were highly correlated with those measured with FSVOI (P < 0.0001. Putaminal SUVR values were highly effective for discriminating PD patients from controls. However, the PET-guided method excessively overestimated striatal SUVR values in the PD patients by more than 30% in caudate and putamen, and thereby spoiled the linearity between the striatal SUVR values in all subjects and showed lower disease discrimination ability. Two CT-guided methods showed

  4. Multispectral guided fluorescence diffuse optical tomography using upconverting nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Svenmarker, Pontus, E-mail: pontus.svenmarker@physics.umu.se [Department of Physics, Lund University, P.O. Box 118, SE-221 00 Lund (Sweden); Department of Physics, Umeå University, SE-901 87 Umeå (Sweden); Centre for Microbial Research (UCMR), Umeå University, SE-901 87 Umeå (Sweden); Xu, Can T.; Liu, Haichun; Wu, Xia; Andersson-Engels, Stefan [Department of Physics, Lund University, P.O. Box 118, SE-221 00 Lund (Sweden)

    2014-02-17

    We report on improved image detectability for fluorescence diffuse optical tomography using upconverting nanoparticles doped with rare-earth elements. Core-shell NaYF{sub 4}:Yb{sup 3+}/Er{sup 3+}@NaYF{sub 4} upconverting nanoparticles were synthesized through a stoichiometric method. The Yb{sup 3+}/Er{sup 3+} sensitizer-activator pair yielded two anti-Stokes shifted fluorescence emission bands at 540 nm and 660 nm, here used to a priori estimate the fluorescence source depth with sub-millimeter precision. A spatially varying regularization incorporated the a priori fluorescence source depth estimation into the tomography reconstruction scheme. Tissue phantom experiments showed both an improved resolution and contrast in the reconstructed images as compared to not using any a priori information.

  5. Computed tomography-guided percutaneous biopsy of pancreatic masses using pneumodissection

    Directory of Open Access Journals (Sweden)

    Chiang Jeng Tyng

    2013-06-01

    Full Text Available Objective To describe the technique of computed tomography-guided percutaneous biopsy of pancreatic tumors with pneumodissection. Materials and Methods In the period from June 2011 to May 2012, seven computed tomography-guided percutaneous biopsies of pancreatic tumors utilizing pneumodissection were performed in the authors' institution. All the procedures were performed with an automatic biopsy gun and coaxial system with Tru-core needles. The biopsy specimens were histologically assessed. Results In all the cases the pancreatic mass could not be directly approached by computed tomography without passing through major organs and structures. The injection of air allowed the displacement of adjacent structures and creation of a safe coaxial needle pathway toward the lesion. Biopsy was successfully performed in all the cases, yielding appropriate specimens for pathological analysis. Conclusion Pneumodissection is a safe, inexpensive and technically easy approach to perform percutaneous biopsy in selected cases where direct access to the pancreatic tumor is not feasible.

  6. Spinal cord infarction following therapeutic computed tomography-guided left L2 nerve root injection.

    Science.gov (United States)

    Somayaji, H S; Saifuddin, A; Casey, A T H; Briggs, T W R

    2005-02-15

    Case report. To report a rare case of spinal cord infarction following therapeutic computed tomography-guided nerve root injection. Diagnostic and therapeutic image-guided nerve root injection is commonly performed in the management of low back pain and sciatica. The severe complication of spinal cord infarction has been reported in only 3 cases previously. Retrospective review of case records and imaging. A 71-year-old woman presented with symptoms and signs of left L2 nerve root compression. She was managed with computed tomography-guided left L2 nerve root injection using bupivacaine and triamcinolone and developed immediate bilateral sensory loss and paraplegia. Magnetic resonance imaging demonstrated diffuse hyperintensity within the distal thoracic cord and conus on T2-weighted images, consistent with spinal cord infarction. We report the fourth case of spinal cord infarction following nerve root injection. The severity of this complication warrants that it should be considered during patient consent for this procedure.

  7. Real-Time Assessment of Guided Bone Regeneration in Standardized Calvarial Defects in Rats Using Bio-Oss With and Without Collagen Membrane: An In Vivo Microcomputed Tomographic and Histologic Experiment.

    Science.gov (United States)

    Nooh, Nasser; Ramalingam, Sundar; Al-Kindi, Mohammed; Al-Rasheed, Abdulaziz; Al-Hamdan, Khalid S; Al-Hezaimi, Khalid

    2016-01-01

    In vivo microcomputed tomography (μCT) enables real-time assessment of bone regeneration. The aim of this μCT and histologic experiment was to assess guided bone regeneration (GBR) around standardized calvarial defects in rats using particulate graft material (Bio-Oss) with and without collagen membranes (CMs). Eighteen female Sprague-Dawley rats aged 6 weeks and weighing 300 g were used. With the rats under general anesthesia, calvaria were exposed and a full-thickness standardized defect was created on the parietal bone. For treatment, rats were randomly assigned to the following three groups: (1) CM group; (2) Bio-Oss group; and (3) Bio-Oss + CM group. Bone volume and bone mineral density (BMD) of newly formed bone (NFB) and remnant bone particles were measured at baseline and 2, 4, 6, and 10 weeks after the operations using real-time in vivo μCT. At 10 weeks, all animals were sacrificed and calvarial tissues were assessed histologically. In the CM group, a significant increase in mean ± standard deviation (SD) BMD of NFB was observed at 6 weeks (0.32 ± 0.02 g/mm(3)) (P Bio-Oss group, mean ± SD volume (3.03 ± 0.14 mm(3)) (P Bio-Oss + CM group, mean ± SD volume (0.98 ± 0.19 mm(3)) and BMD (0.13 ± 0.01 g/mm(3)) of NFB significantly increased at 4 weeks compared with baseline (P Bio-Oss + CM group, mean ± SD volume (3.5 ± 0.7 mm(3)) and BMD (0.44 ± 0.03 g/mm(3)) of remnant bone particles were significantly reduced at 10 weeks compared with baseline values (5.8 ± 0.96 mm(3) and 1.3 ± 0.02 g/mm(3)) (P Bio-Oss + CM group exhibited the most. The results of this study revealed that, in real time, new bone formation starts as early as 4 weeks in standardized calvarial defects undergoing GBR with Bio-Oss + CM, compared with new bone formation at 6 weeks in defects undergoing GBR with Bio-Oss alone.

  8. A Practical Guide to Photoacoustic Tomography in the Life Sciences

    Science.gov (United States)

    Wang, Lihong V.; Yao, Junjie

    2016-01-01

    The life sciences can benefit greatly from imaging technologies that connect microscopic discoveries with macroscopic observations. Photoacoustic tomography (PAT), a highly sensitive modality for imaging rich optical absorption contrast over a wide range of spatial scales at high speed, is uniquely positioned for this need. In PAT, endogenous contrast reveals tissue’s anatomical, functional, metabolic, and histologic properties, and exogenous contrast provides molecular and cellular specificity. The spatial scale of PAT covers organelles, cells, tissues, organs, and small-animal organisms. Consequently, PAT is complementary to other imaging modalities in contrast mechanism, penetration, spatial resolution, and temporal resolution. We review the fundamentals of PAT and provide practical guidelines to the broad life science community for matching PAT systems with research needs. We also summarize the most promising biomedical applications of PAT, discuss related challenges, and envision its potential to lead to further breakthroughs. PMID:27467726

  9. Early-photon guided reconstruction method for time-domain fluorescence lifetime tomography

    Institute of Scientific and Technical Information of China (English)

    Lin Zhang; Chuangjian Cai; Yanlu Lv; Jianwen Luo

    2016-01-01

    A reconstruction method guided by early-photon fluorescence yield tomography is proposed for time-domain fluorescence lifetime tomography (FLT) in this study.The method employs the early-arriving photons to reconstruct a fluorescence yield map,which is utilized as a priori information to reconstruct the FLT via all the photons along the temporal-point spread functions.Phantom experiments demonstrate that,compared with the method using all the photons for reconstruction of fluorescence yield and lifetime maps,the proposed method can achieve higher spatial resolution and reduced crosstalk between different targets without sacrificing the quantification accuracy of lifetime and contrast between heterogeneous targets.

  10. Computed tomography guided needle biopsy in the head and neck region

    Directory of Open Access Journals (Sweden)

    Aris NTOMOUCHTSIS, Maria PANAGIOTOPOULOU, Kostas PARASKEVOPOULOS,

    2011-08-01

    Full Text Available SUMMARY: Introduction: The search for new methods of diagnostic identification of lesions and diseases in cases posing differential diagnostic challenges, as well as the objective of creating the least possible discomfort for patients, have led to the application and use of new technologies. Guided biopsy is a technique used to obtain biopsy samples, avoiding open biopsy and by extension, the possibility of tumour dissemination. Aim: In this paper, we seek to present the experience we have gained from using computed tomography guided needle biopsy in cases involving differential diagnostic difficulties. Material-Method: This technique was applied in cases of lesions in the head and neck region,where neither fine needle aspiration cytology (FNAC nor open biopsy could be used to establish diagnosis. In areas where post-operation or post-radiation scars are present,imaging is necessary, especially when suspicion of recurrence is raised. The identification of benign lesions or local recurrence of malignant tumours can help prevent surgical interventions or malpractices. Results: The diagnostic accuracy of computed tomography guided needle biopsy was very high, since in 90% of the cases presented here it helped establish the correct diagnosis. Conclusions:Computed tomography guided needle biopsy is a safe technique in the hands of experienced interventional radiologists and maxillofacial surgeons.

  11. Optical coherence tomography-guided classification of epiretinal membranes.

    Science.gov (United States)

    Konidaris, Vasileios; Androudi, Sofia; Alexandridis, Alexandros; Dastiridou, Anna; Brazitikos, Periklis

    2015-08-01

    To study and classify epiretinal membranes (ERMs) based on spectral domain optical coherence tomography (SD-OCT) findings. One hundred and twelve patients with ERMs were examined clinically and underwent OCT examination. The anatomical structure of the macula and vitreoretinal interface was studied. ERMs were classified in two categories: A, with posterior vitreous detachment (PVD) (91 cases), and B, with the absence of PVD (21 cases). Category A was divided into two subcategories: A1, without contraction of the ERM (37 cases), and A2, with the presence of membrane contraction (54 cases). A2 was further subdivided into A2.1, with retinal folding (15 cases), A2.2, with edema (23 cases), A2.3, with cystoid macular edema (9 cases), and A2.4, with lamellar macular hole (7 cases). Category B was divided in two subcategories: B1, without vitreomacular traction (VMT) (4 cases), and B2, with the presence of VMT (17 cases). Category B2 was subdivided into B2.1, with edema (9 cases), B2.2, presenting retinal detachment (5 cases), and B2.3, with schisis (3 cases). OCT classification of ERMs provides useful information on the anatomical structure of the retina, and the accurate estimation of vitreoretinal interface.

  12. Optical coherence tomography in guided surgery of GI cancer

    Science.gov (United States)

    Zagaynova, Elena V.; Abelevich, Alexander I.; Zagaynov, Vladimir E.; Gladkova, Natalia D.; Denisenko, Arkady N.; Feldchtein, Felix I.; Snopova, Ludmila B.; Kutis, Irina S.

    2005-04-01

    Optical Coherence Tomography (OCT) is a new high spatial resolution, real-time optical imaging modality, known from prior pilot studies for its high sensitivity to invasive cancer. We reported our results in an OCT feasibility study for accurate determination of the proximal border for esophageal carcinoma and the distal border for rectal carcinoma. The OCT study enrolled 19 patients with rectal adenocarcinoma and 24 patients with distal esophageal carcinoma (14 squamous cell carcinomas, 10 adenocarcinomas). During pre-surgery planning endoscopy we performed in vivo OCT imaging of the tumor border at four dial clock axes (12, 3, 6 and 9 o"clock). The OCT border then was marked by an electrocoagulator, or by a methylene blue tattoo. A cold biopsy (from the esophagus) was performed at visual and OCT borders and compared with visual and OCT readings. 27 post-surgery excised specimens were analyzed. OCT borders matched the histopathology in 94% cases in the rectum and 83.3% in the esophagus. In the cases of a mismatch between the OCT and histology borders, a deep tumor invasion occurred in the muscle layer (esophagus, rectum). Because of its high sensitivity to mucosal cancer, OCT can be used for pre-surgery planning and surgery guidance of the proximal border for esophageal carcinoma and the distal border for rectal carcinoma. However, deep invasion in the rectum or esophageal wall has to be controlled by alternative diagnostic modalities.

  13. Diagnostic yield and complications of transthoracic computed tomography-guided biopsies

    DEFF Research Database (Denmark)

    Vagn-Hansen, Chris Aksel; Pedersen, Malene Roland Vils; Rafaelsen, Søren Rafael

    2016-01-01

    INTRODUCTION: The widespread use of computed tomography (CT) improves detection of pulmonary lesions, which are not only detected at an increased rate but also at a smaller size. CT-guided lung biopsies are now more frequently used than fluoroscopy-guided lung biopsies. The main aim of the present...... paper was to investigate the outcome and complications of the biopsies. METHODS: We retrospectively collected the results and information from 520 CT-guided thorax biopsies. All biopsies were performed with CT-guided “beam-through” technique, using a 64-slice CT scanner. RESULTS: In 86% of the biopsies......, the tissue material was found to be sufficient. In 32% of the biopsies, a complication arose, mostly pneumothorax (30%), but chest drainage was needed in only 15% of the 520 cases. Patients with more than ten cigarette pack-years had a complication risk that was twice as high at that of patients with fewer...

  14. Initial Experience with a Cone-beam Breast Computed Tomography-guided Biopsy System

    Science.gov (United States)

    Seifert, Posy J; Morgan, Renee C; Conover, David L; Arieno, Andrea L

    2017-01-01

    Objective: To evaluate our initial experience with a cone-beam breast computed tomography (BCT)-guided breast biopsy system for lesion retrieval in phantom studies for use with a cone-beam BCT imaging system. Materials and Methods: Under the Institutional Review Board approval, a phantom biopsy study was performed using a dedicated BCT-guided biopsy system. Fifteen biopsies were performed on each of the small, medium, and large anthropomorphic breast phantoms with both BCT and stereotactic guidance for comparison. Each set of the 45 phantoms contained masses and calcification clusters of varying sizes. Data included mass/calcium retrieval rate and dose and length of procedure time for phantom studies. Results: Phantom mass and calcium retrieval rate were 100% for BCT and stereotactic biopsy. BCT dose for small and medium breast phantoms was found to be equivalent to or less than the corresponding stereotactic approach. Stereotactic-guided biopsy dose was 34.2 and 62.5 mGy for small and medium breast phantoms, respectively. BCT-guided biopsy dose was 15.4 and 30.0 mGy for small and medium breast phantoms, respectively. Both computed tomography biopsy and stereotactic biopsy study time ranged from 10 to 20 min. Conclusion: Initial experience with a BCT-guided biopsy system has shown to be comparable to stereotactic biopsy in phantom studies with equivalent or decreased dose. PMID:28217404

  15. Multiple large splenic abscesses managed with computed tomography-guided percutaneous catheter drainage in children.

    Science.gov (United States)

    Yeom, Jung Sook; Park, Ji Sook; Seo, Ji-Hyun; Park, Eun Sil; Lim, Jae-Young; Park, Chan Hoo; Woo, Hyang Ok; Park, Jung Je; Cho, Jae Min; Youn, Hee-Shang

    2013-12-01

    Splenic abscess is a rare finding in children. Splenectomy combined with broad-spectrum antibiotics has been the treatment of choice for multiple splenic abscesses. Herein, we report the case of a 14-year-old girl with multiple large splenic abscesses that were successfully managed after two image-guided percutaneous drainage procedures and administration of intravenous antibiotics. Initially, an abscess located at the periphery in the lower pole of the spleen was aspirated under ultrasound guidance. Finally, another abscess located near the hilum of the spleen was drained under computed tomography guidance. To the best of our knowledge, this is the first report of multiple large splenic abscesses treated with computed tomography-guided percutaneous drainage.

  16. Understanding the micro structure of Berea Sandstone by the simultaneous use of micro-computed tomography (micro-CT) and focused ion beam-scanning electron microscopy (FIB-SEM).

    Science.gov (United States)

    Bera, Bijoyendra; Mitra, Sushanta K; Vick, Douglas

    2011-07-01

    Berea sandstone is the building block for reservoirs containing precious hydrocarbon fuel. In this study, we comprehensively reveal the microstructure of Berea sandstone, which is often treated as a porous material with interconnected micro-pores of 2-5 μm. This has been possible due to the combined application of micro-computed tomography (CT) and focused ion beam (FIB)-scanning electron microscopy (SEM) on a Berea sample. While the use of micro-CT images are common for geological materials, the clubbing and comparison of tomography on Berea with state-of-the-art microstructure imaging techniques like FIB-SEM reveals some unforeseen features of Berea microstructure. In particular, for the first time FIB-SEM has been used to understand the micro-structure of reservoir rock material like Berea sandstone. By using these characterization tools, we are able to show that the micro-pores (less than 30 μm) are absent below the solid material matrix, and that it has small interconnected pores (30-40 μm) and large crater-like voids (100-250 μm) throughout the bulk material. Three-dimensional pore space reconstructions have been prepared from the CT images. Accordingly, characterization of Berea sandstone specimen is performed by calculation of pore-structure volumes and determination of porosity values.

  17. Computed tomography-guided core-needle biopsy of lung lesions: an oncology center experience

    Energy Technology Data Exchange (ETDEWEB)

    Guimaraes, Marcos Duarte; Fonte, Alexandre Calabria da; Chojniak, Rubens, E-mail: marcosduarte@yahoo.com.b [Hospital A.C. Camargo, Sao Paulo, SP (Brazil). Dept. of Radiology and Imaging Diagnosis; Andrade, Marcony Queiroz de [Hospital Alianca, Salvador, BA (Brazil); Gross, Jefferson Luiz [Hospital A.C. Camargo, Sao Paulo, SP (Brazil). Dept. of Chest Surgery

    2011-03-15

    Objective: The present study is aimed at describing the experience of an oncology center with computed tomography guided core-needle biopsy of pulmonary lesions. Materials and Methods: Retrospective analysis of 97 computed tomography-guided core-needle biopsy of pulmonary lesions performed in the period between 1996 and 2004 in a Brazilian reference oncology center (Hospital do Cancer - A.C. Camargo). Information regarding material appropriateness and the specific diagnoses were collected and analyzed. Results: Among 97 lung biopsies, 94 (96.9%) supplied appropriate specimens for histological analyses, with 71 (73.2%) cases being diagnosed as malignant lesions and 23 (23.7%) diagnosed as benign lesions. Specimens were inappropriate for analysis in three cases. The frequency of specific diagnosis was 83 (85.6%) cases, with high rates for both malignant lesions with 63 (88.7%) cases and benign lesions with 20 (86.7%). As regards complications, a total of 12 cases were observed as follows: 7 (7.2%) cases of hematoma, 3 (3.1%) cases of pneumothorax and 2 (2.1%) cases of hemoptysis. Conclusion: Computed tomography-guided core needle biopsy of lung lesions demonstrated high rates of material appropriateness and diagnostic specificity, and low rates of complications in the present study. (author)

  18. Uncommon primary tumors of the orbit diagnosed by computed tomography-guided core needle biopsy: report of two cases

    Energy Technology Data Exchange (ETDEWEB)

    Tyng, Chiang Jeng; Matushita Junior, Joao Paulo Kawaoka; Bitencourt, Almir Galvao Vieira; Amoedo, Mauricio Kauark; Barbosa, Paula Nicole Vieira; Chojniak, Rubens, E-mail: almirgvb@yahoo.com.br [A.C.Camargo Cancer Center, Sao Paulo, SP (Brazil). Dept. de Imagem; Neves, Flavia Branco Cerqueira Serra [Hospital do Servidor Publico Estadual, Sao Paulo, SP (Brazil). Div. de Oftalmologia

    2014-11-15

    Computed tomography-guided percutaneous biopsy is a safe and effective alternative method for evaluating selected intra-orbital lesions where the preoperative diagnosis is important for the therapeutic planning. The authors describe two cases of patients with uncommon primary orbital tumors whose diagnosis was obtained by means of computed tomography-guided core needle biopsy, with emphasis on the technical aspects of the procedure. (author)

  19. Three-dimensional visualisation of the internal anatomy of the sparrowhawk (Accipiter nisus) forelimb using contrast-enhanced micro-computed tomography.

    Science.gov (United States)

    Bribiesca-Contreras, Fernanda; Sellers, William I

    2017-01-01

    Gross dissection is a widespread method for studying animal anatomy, despite being highly destructive and time-consuming. X-ray computed tomography (CT) has been shown to be a non-destructive alternative for studying anatomical structures. However, in the past it has been limited to only being able to visualise mineralised tissues. In recent years, morphologists have started to use traditional X-ray contrast agents to allow the visualisation of soft tissue elements in the CT context. The aim of this project is to assess the ability of contrast-enhanced micro-CT (μCT) to construct a three-dimensional (3D) model of the musculoskeletal system of the bird wing and to quantify muscle geometry and any systematic changes due to shrinkage. We expect that this reconstruction can be used as an anatomical guide to the sparrowhawk wing musculature and form the basis of further biomechanical analysis of flight. A 3% iodine-buffered formalin solution with a 25-day staining period was used to visualise the wing myology of the sparrowhawk (Accipiter nisus). μCT scans of the wing were taken over the staining period until full penetration of the forelimb musculature by iodine was reached. A 3D model was reconstructed by manually segmenting out the individual elements of the avian wing using 3D visualisation software. Different patterns of contrast were observed over the duration of the staining treatment with the best results occurring after 25 days of staining. Staining made it possible to visualise and identify different elements of the soft tissue of the wing. Finally, a 3D reconstruction of the musculoskeletal system of the sparrowhawk wing is presented and numerical data of muscle geometry is compared to values obtained by dissection. Contrast-enhanced μCT allows the visualisation and identification of the wing myology of birds, including the smaller muscles in the hand, and provides a non-destructive way for quantifying muscle volume with an accuracy of 96.2%. By combining

  20. Three-dimensional visualisation of the internal anatomy of the sparrowhawk (Accipiter nisus forelimb using contrast-enhanced micro-computed tomography

    Directory of Open Access Journals (Sweden)

    Fernanda Bribiesca-Contreras

    2017-03-01

    Full Text Available Background Gross dissection is a widespread method for studying animal anatomy, despite being highly destructive and time-consuming. X-ray computed tomography (CT has been shown to be a non-destructive alternative for studying anatomical structures. However, in the past it has been limited to only being able to visualise mineralised tissues. In recent years, morphologists have started to use traditional X-ray contrast agents to allow the visualisation of soft tissue elements in the CT context. The aim of this project is to assess the ability of contrast-enhanced micro-CT (μCT to construct a three-dimensional (3D model of the musculoskeletal system of the bird wing and to quantify muscle geometry and any systematic changes due to shrinkage. We expect that this reconstruction can be used as an anatomical guide to the sparrowhawk wing musculature and form the basis of further biomechanical analysis of flight. Methods A 3% iodine-buffered formalin solution with a 25-day staining period was used to visualise the wing myology of the sparrowhawk (Accipiter nisus. μCT scans of the wing were taken over the staining period until full penetration of the forelimb musculature by iodine was reached. A 3D model was reconstructed by manually segmenting out the individual elements of the avian wing using 3D visualisation software. Results Different patterns of contrast were observed over the duration of the staining treatment with the best results occurring after 25 days of staining. Staining made it possible to visualise and identify different elements of the soft tissue of the wing. Finally, a 3D reconstruction of the musculoskeletal system of the sparrowhawk wing is presented and numerical data of muscle geometry is compared to values obtained by dissection. Discussion Contrast-enhanced μCT allows the visualisation and identification of the wing myology of birds, including the smaller muscles in the hand, and provides a non-destructive way for quantifying

  1. Doing Physics with Microcomputers.

    Science.gov (United States)

    Bak, Per

    1983-01-01

    Describes how microcomputers can perform very demanding/large-scale physics calculations at speeds not much slower than those of modern, full-size computers. Among the examples provided are a Monte Carlo simulation of the three-dimensional Ising model and a program (for the Apple microcomputer) using the time-independent Schrodinger Equation. (JN)

  2. Problem Solving Using Microcomputers.

    Science.gov (United States)

    Demana, Franklin; Waits, Bert

    1987-01-01

    It is argued that microcomputer technology has evolved to the stage that it should be routinely used by mathematics students at all levels. It is shown how the use of microcomputers can change the way problems are solved. Computer-generated graphics are highlighted. (PK)

  3. Sketching with a microcomputer

    DEFF Research Database (Denmark)

    Jacobi, P.

    This report describes the use of a microcomputer as a tool for the sketch design phase of the building process. A housing development scheme comprising 175 dwellings is chosen for illustrating the procedures. Here the microcomputer is utilized for analysing the landscape, for the three-dimensiona...

  4. The Microcomputer Revolution.

    Science.gov (United States)

    Kinne, Harold C.

    The history of the development of the microcomputer industry since its inception in 1975 is explored in this brief paper, which pays special attention to the advent of the small business computer. The author describes the growth of sales, the development of successful companies, the early resistance to use of microcomputers in business, and the…

  5. Guided-wave tomography imaging plate defects by laser-based ultrasonic techniques

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jun Pil; Lim, Ju Young; Cho, Youn Ho [School of Mechanical Engineering, Pusan National University, Pusan (Korea, Republic of)

    2014-12-15

    Contact-guided-wave tests are impractical for investigating specimens with limited accessibility and rough surfaces or complex geometric features. A non-contact setup with a laser-ultrasonic transmitter and receiver is quite attractive for guided-wave inspection. In the present work, we developed a non-contact guided-wave tomography technique using the laser-ultrasonic technique in a plate. A method for Lamb-wave generation and detection in an aluminum plate with a pulsed laser-ultrasonic transmitter and Michelson-interferometer receiver was developed. The defect shape and area in the images obtained using laser scanning, showed good agreement with the actual defect. The proposed approach can be used as a non-contact online inspection and monitoring technique.

  6. Computed tomography-guided percutaneous radiofrequency thermocoagulation for primary trigeminal neuralgia in older and younger patients

    Institute of Scientific and Technical Information of China (English)

    Guanghui Lai; Jiaxiang Ni; Baishan Wu; Mingwei He; Liqiang Yang; Jianning Yue; Yuna Guo

    2011-01-01

    We evaluated the immediate and long-term clinical efficacy of computed tomography (CT)-guided radiofrequency thermocoagulation for primary trigeminal neuralgia (RTPTN) in 852 patients includ-ing 502 patients aged ≥ 60 years and 350 patients aged < 60 years. After discharge, the incidence of complications was 1.0% and 0.9% in patients aged ≥ 60 years and patients aged < 60 years, respectively. Over 3-year follow-up after CT-guided RTPTN, 96.8% of the patients aged ≥ 60 years and 98.6% of the patients aged < 60 years were completely pain-free, and there was no significant difference between these two age brackets. In addition, there were no significant differences in quality of life scores and numbness scores between these two age brackets. These findings suggest that CT-guided RTPTN is a safe and effective method and is recommended for older and poor-risk patients.

  7. Combination of nonlinear ultrasonics and guided wave tomography for imaging the micro-defects.

    Science.gov (United States)

    Li, Weibin; Cho, Younho

    2016-02-01

    The use of guided wave tomography has become an attractive alternative to convert ultrasonic wave raw data to visualized results for quantitative signal interpretation. For more accurate life prediction and efficient management strategies for critical structural components, there is a demand of imaging micro-damages in early stage. However, there is rarely investigation on guided wave tomographic imaging of micro-defects. One of the reasons for this might be that it becomes challenging to monitor tiny signal difference coefficient in a reliable manner for wave propagation in the specimens with micro-damages. Nonlinear acoustic signal whose frequency differs from that of the input signal can be found in the specimens with micro-damages. Therefore, the combination of guided wave tomography and nonlinear acoustic response induced by micro-damages could be a feasibility study for imaging micro-damages. In this paper, the nonlinear Rayleigh surface wave tomographic method is investigated to locate and size micro-corrosive defect region in an isotropic solid media. The variations of acoustic nonlinear responses of ultrasonic waves in the specimens with and without defects are used in guided wave tomographic algorithm to construct the images. The comparisons between images obtained by experimental signals and real defect region induced by hydrogen corrosion are presented in this paper. Results show that the images of defect regions with different shape, size and location are successfully obtained by this novel technique, while there is no visualized result constructed by conventional linear ultrasonic tomographic one. The present approach shows a potential for inspecting, locating and imaging micro-defects by nonlinear Rayleigh surface wave tomography. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Computed tomography-guided resection of osteoid osteoma of the sacrum: a case report.

    Science.gov (United States)

    Fukuda, Shinsuke; Susa, Michiro; Watanabe, Itsuo; Nishimoto, Kazumasa; Horiuchi, Keisuke; Toyama, Yoshiaki; Morioka, Hideo

    2014-06-18

    Osteoid osteoma is a benign tumor that usually occurs in the long bones of young adults. Its symptoms can be diverse depending on the location of the tumor and especially difficult to diagnose when occurring in an atypical location. Osteoid osteoma arising in the sacrum is extremely rare, and here, we present a case that was treated successfully in a minimally invasive fashion under computed tomography guidance. A 25-year-old Asian man was referred to our institution due to persistent pain in the buttock after 12 months of conservative treatment. Computed tomography and magnetic resonance imaging scans revealed a ring-shaped radiolucency consistent with a nidus of osteoid osteoma in the sacrum. The lesion was subsequently resected under computed tomography guidance and the histological diagnosis was compatible with osteoid osteoma. His postoperative course was uneventful, and at two years after surgery our patient is symptom-free with no evidence of recurrence. Computed tomography-guided resection of osteoid osteoma in the spinal column is feasible and accurate if there is adequate margin from vital organs. Although rare, it is important to always bear in mind the possibility of osteoid osteoma occurring in the sacrum when no other apparent lesion is detected.

  9. Microcomputer Applications in Analytical Chemistry.

    Science.gov (United States)

    Long, Joseph W.

    The first part of this paper addresses the following topics: (1) the usefulness of microcomputers; (2) applications for microcomputers in analytical chemistry; (3) costs; (4) major microcomputer systems and subsystems; and (5) which microcomputer to buy. Following these brief comments, the major focus of the paper is devoted to a discussion of…

  10. Spontaneous Coronary Dissection: “Live Flash” Optical Coherence Tomography Guided Angioplasty

    Science.gov (United States)

    Bento, Angela Pimenta; Fernandes, Renato Gil dos Santos Pinto; Neves, David Cintra Henriques Silva; Patrício, Lino Manuel Ribeiro; de Aguiar, José Eduardo Chambel

    2016-01-01

    Optical Coherence tomography (OCT) is a light-based imaging modality which shows tremendous potential in the setting of coronary imaging. Spontaneous coronary artery dissection (SCAD) is an infrequent cause of acute coronary syndrome (ACS). The diagnosis of SCAD is made mainly with invasive coronary angiography, although adjunctive imaging modalities such as computed tomography angiography, IVUS, and OCT may increase the diagnostic yield. The authors describe a clinical case of a young woman admitted with the diagnosis of ACS. The ACS was caused by SCAD detected in the coronary angiography and the angioplasty was guided by OCT. OCT use in the setting of SCAD has been already described and the true innovation in this case was this unique use of OCT. The guidance of angioplasty with live and short images was very useful as it allowed clearly identifying the position of the guidewires at any given moment without the use of prohibitive amounts of contrast. PMID:26989520

  11. Breast cancer detection using Ktrans MRI imaging to guide near infrared spectroscopy tomography

    Science.gov (United States)

    Feng, Jinchao; Jiang, Shudong; Xu, Junqing; Zhao, Yan; Gui, Jiang; Pogue, Brian W.; Paulsen, Keith D.

    2017-02-01

    The parametric image of Volume Transfer Coefficient (Ktrans) in MRI has been used to guide image reconstruction of Near-Infrared Spectral Tomography (NIRST). The image reconstruction used direct regularization, in which no segmentation has been involved. A total of 24 patients were involved in this study and the reconstructed results show that the tumor total hemoglobin (HbT) contrast could be used to differentiate the malignant from the benign cases (p-value= 0.018). The addition of the MRI information allows more accurate and definitive HbT values from the NIRST.

  12. Optical coherence tomography in diagnostics and guided surgery of bladder cancer

    Science.gov (United States)

    Zagaynova, Elena; Streltzova, Olga; Gladkova, Natalia D.; Shakhova, Natalia M.; Feldchtein, Felix I.; Kamensky, Vladislav A.; Gelikonov, Grigory V.; Donchenko, Ekaterina

    2004-07-01

    We performed blind recognition of optical coherence tomography (OCT) images of human urinary bladder for diagnostics of carcinoma and premalignant conditions. OCT images of 63 patients were acquired in vivo during cystoscopic examination. The malignant/premalignant conditions were differentiated from benign/reactive with 98% sensitivity and 72% specificity. OCT was also used for intraoperative monitoring of zones around the tumor for adequate resection (31 patients). OCT - guided planning of the resection margin and examination of the postoperative resection line after transurethral resection (TUR) was performed.

  13. Computer tomography guided lung biopsy using interactive breath-hold control

    DEFF Research Database (Denmark)

    Ashraf, Haseem; Krag-Andersen, Shella; Naqibullah, Matiullah

    2017-01-01

    BACKGROUND: Interactive breath-hold control (IBC) may improve the accuracy and decrease the complication rate of computed tomography (CT)-guided lung biopsy, but this presumption has not been proven in a randomized study. METHODS: Patients admitted for CT-guided lung biopsy were randomized...... to biopsy either with (N=201) or without (N=206) IBC. Biopsy accuracy, procedure time, radiation, and complications were compared in the two groups. Predictors for pneumothorax were analyzed. RESULTS: Procedures performed with the use of IBC (N=130) did not show higher biopsy accuracy (P=0.979) but were...... associated with a higher risk of pneumothorax (P=0.022) compared to procedures without the use of IBC (N=171). Overall, 50% of the biopsies were malignant, 13% were benign, and 33% were inconclusive (4% missing). Long needle time (P=0.037) and small nodule size (P=0.001) were predictors of pneumothorax...

  14. Limited-view ultrasonic guided wave tomography using an adaptive regularization method

    Science.gov (United States)

    Rao, Jing; Ratassepp, Madis; Fan, Zheng

    2016-11-01

    Ultrasonic guided waves are useful to assess the integrity of a structure from a remote location. Recently, tomography techniques have been developed to quantitatively estimate the thickness map of plate-like structures based on the dispersion characteristics of guided waves. In many applications only limited locations are available to place transducers. The missing viewing angles lead to artifacts which can degrade the image quality. To address this problem, this paper applies the regularization method to synthesize the missing components. The regularization technique is performed by an adaptive threshold approach to the limited view reconstruction. The effectiveness of this method combined with the full waveform inversion method is demonstrated by using numerical simulations as well as experiments on an irregularly shaped defect and two flat-bottom defects. The results indicate that the additional components obtained from the regularization method can significantly reduce the artifacts, leading to better reconstruction accuracy.

  15. Computed tomography-guided percutaneous biopsy of bone lesions: rate of diagnostic success and complications

    Energy Technology Data Exchange (ETDEWEB)

    Maciel, Macello Jose Sampaio; Tyng, Chiang Jeng; Barbosa, Paula Nicole Vieira Pinto; Bitencourt, Almir Galvao Vieira; Matushita Junior, Joao Paulo Kawaoka; Zurstrassen, Charles Edouard; Chung, Wu Tu; Chojniak, Rubens, E-mail: macellomaciel@me.com [A.C.Camargo Cancer Center, Sao Paulo, SP (Brazil)

    2014-09-15

    Objective: To determine the rates of diagnostic success and complications of computed tomography (CT)-guided percutaneous biopsy of bone lesions suspected for malignancy. Materials and Methods: Retrospective study including 186 cases of CT-guided percutaneous biopsies of bone lesions in the period from January, 2010 to December, 2012. All the specimens were obtained with 8-10 gauge needles. The following data were collected: demographics, previous history of malignancy, data related to the lesion, to the procedure, and to histological results. Results: Most patients were women (57%), and the mean age was 53.0 ± 16.4 years. In 139 cases (74.6%), there was diagnostic suspicion of metastasis and the most common primary tumors were breast (32.1%) and prostate (11.8%). The bones most commonly involved were spine (36.0%), hip (32.8%) and long bones (18.3%). Complications occurred in only three cases (1.6%) including bone fracture, paraesthesia with functional impairment, and needle breakage requiring surgical removal. The specimens collected from 183 lesions (98.4%) were considered appropriate for diagnosis. Malignant results were more frequently found in patients who had a suspected secondary lesion and history of known malignancy (p < 0.001), and in patients who underwent PET/CT-guided procedures (p = 0.011). Conclusion: CT-guided percutaneous biopsy is a safe and effective procedure for the diagnosis of suspicious bone lesions. (author)

  16. Experimental Validation of a Fast Forward Model for Guided Wave Tomography of Pipe Elbows.

    Science.gov (United States)

    Brath, Alex J; Simonetti, Francesco; Nagy, Peter B; Instanes, Geir

    2017-05-01

    Ultrasonic guided wave tomography (GWT) methods for the detection of corrosion and erosion damage in straight pipe sections are now well advanced. However, successful application of GWT to pipe bends has not yet been demonstrated due to the computational burden associated with the complex forward model required to simulate guided wave propagation through the bend. In a previous paper [Brath et al., IEEE Trans. Ultrason., Ferroelectr., Freq. Control, vol. 61, pp. 815-829, 2014], we have shown that the speed of the forward model can be increased by replacing the 3-D pipe bend with a 2-D rectangular domain in which guided wave propagation is formulated based on an artificially inhomogeneous and elliptically anisotropic (INELAN) acoustic model. This paper provides further experimental validation of the INLEAN model by studying the traveltime shifts caused by the introduction of shallow defects on the elbow of a pipe bend. Comparison between experiments and simulations confirms that a defect can be modeled as a phase velocity perturbation to the INLEAN velocity field with accuracy that is within the experimental error of the measurements. In addition, it is found that the sensitivity of traveltime measurements to the presence of damage decreases as the damage position moves from the interior side of the bend (intrados) to the exterior one (extrados). This effect is due to the nonuniform ray coverage obtainable when transmitting the guided wave signals with one ring array of sources on one side of the elbow and receiving with a second array on the other side.

  17. Computed Tomography-guided Pericardiocentesis: An alternative approach for accessing the pericardium.

    Science.gov (United States)

    Melvan, John Nicholas; Madden, David; Vasquez, Julio C; DeLaRosa, Jacob

    2016-07-01

    Pericardial effusions compress the heart, decrease cardiac output, and lead to haemodynamic collapse. Ultrasound (US)-guided pericardiocentesis is the gold standard for treating pericardial effusions. Recently, the incorporation of computed tomography (CT) guidance has increased patient safety while entering the pericardium. Despite the superior performance of CT-guided pericardiocentesis in smaller, complex effusions, this procedure is not routinely performed by cardiologists and surgeons. Unlike those with an intact pericardium, patients with mediastinal trauma, pericardial adhesions, temporary pacing wires, and vascular conduits are high risk for pericardiocentesis. Tamponade physiology also increases patient susceptibility to the hypotensive effects of anaesthesia during surgical drainage. Here we illustrate the technique of CT-guided pericardiocentesis and demonstrate its application in specific clinical scenarios. We conclude that CT-guided pericardiocentesis provides a useful, alternative strategy for treating cardiac tamponade in high risk patients. Copyright © 2016 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

  18. Incidental finding of a left over guide wire on a positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Yap, Kok Hooi; Lee, Phong Teck; Buch, Mamta; Rammohan, Kandadai Seshadri

    2012-12-15

    The Seldinger technique is commonly used cannulate vessels for radiographical procedures. Loss of a guide wire into the circulation is a rare and preventable complication. It is often noticed by chance during routine radiographs. However, there is a lack of reported cases of incidental fin dings of leftover guide wire on a PET scan. An intravascular foreign body should be retrieved as soon as the diagnosis is made, to prevent complications such as embolisation or vascular damage by fractured wires. Interventional radiology is the method of choice for retrieval. We report a rare case of the coincidental finding of a lost guide wire on a PET scan. A 37 year old man presented with psychotic episodes, thigh weakness, weight gain, increased appetite and leg cramps. He was subsequently diagnosed with cushing syndrome secondary to ectopic adrenocorticotropic secretion from a right lung tumour. He subsequently underwent a staging positron emission tomography (PET) scan. The lung tumour had no uptake on PET bit had increased activity uptake on octreotide scanning. These appearances were suggestive of with carcinoid tumour. The PET scan also revealed an incidental finding of a leftover guide wire used during peripheral inserted central catheter (PICC) recently. The wire extended from right atrium to inferior vena cava. It also showed a high uptake in the adrenal glands, indicating hyperplasia, which was most likely due to adrenocorticotropic hormone stimulation. He underwent a percutaneous wire retrieval via the right femoral vein in a cardiac catheterisation laboratory and was transferred to a thoracic surgical unit for lung tumor resection.

  19. Lamb mode selection for accurate wall loss estimation via guided wave tomography

    Energy Technology Data Exchange (ETDEWEB)

    Huthwaite, P.; Ribichini, R.; Lowe, M. J. S.; Cawley, P. [Department of Mechanical Engineering, Imperial College, London, SW7 2AZ (United Kingdom)

    2014-02-18

    Guided wave tomography offers a method to accurately quantify wall thickness losses in pipes and vessels caused by corrosion. This is achieved using ultrasonic waves transmitted over distances of approximately 1–2m, which are measured by an array of transducers and then used to reconstruct a map of wall thickness throughout the inspected region. To achieve accurate estimations of remnant wall thickness, it is vital that a suitable Lamb mode is chosen. This paper presents a detailed evaluation of the fundamental modes, S{sub 0} and A{sub 0}, which are of primary interest in guided wave tomography thickness estimates since the higher order modes do not exist at all thicknesses, to compare their performance using both numerical and experimental data while considering a range of challenging phenomena. The sensitivity of A{sub 0} to thickness variations was shown to be superior to S{sub 0}, however, the attenuation from A{sub 0} when a liquid loading was present was much higher than S{sub 0}. A{sub 0} was less sensitive to the presence of coatings on the surface of than S{sub 0}.

  20. Cauda equina syndrome caused by epidural pneumorrhachis: treatment with percutaneous computed tomography-guided translaminar trephination.

    Science.gov (United States)

    Paik, Nam Chull; Lim, Chun Soo; Jang, Ho Suk

    2013-04-01

    A case report and review of the literature. To present a rare case, and its treatment, of cauda equina syndrome (CES) caused by epidural pneumorrhachis after repeated caudal epidural injections. Pneumorrhachis is defined as the presence of air in the epidural or subarachnoid space. Epidural pneumorrhachis is usually asymptomatic and managed conservatively, but rare cases of lumbar radiculopathy resulting from epidural air have been reported. To the best of our knowledge, there has been no previous report of CES caused by epidural air. A 63-year-old male presented with recent aggravation of a low backache, with pain radiating to both lower limbs. He also complained of newly developed numbness in the buttocks, groins, and perineum, and difficulty with urination and defecation, after repeated caudal epidural injections during a 3-week period. Computed tomography and magnetic resonance imaging revealed epidural pneumorrhachis compressing the lumbar dural sac at the L2-L3 and L3-L4 levels. The patient's symptoms persisted despite 3 days of oxygen inhalation therapy. Attempted needle aspiration of the epidural air was unsuccessful and percutaneous computed tomography-guided translaminar trephination was performed. The day after trephination, the patient's lower extremity motor strength began to improve; sphincter dysfunction began to resolve on the second day. During 8 weeks, his pain resolved and he gradually regained sensation. Two years later, the patient was free of symptoms or signs of CES. Epidural pneumorrhachis may cause dural sac compression, thus worsening a patient's previous symptoms and possibly eliciting new problems such as CES. Conservative treatment should be the first-line approach, but surgery is often necessary when the problem remains unsolved. Percutaneous computed tomography-guided translaminar trephination may be an alternative to surgical decompression of the epidural space in selected patients.

  1. Value of computed tomography-guided core needle biopsy in diagnosis of primary pulmonary lymphomas.

    Science.gov (United States)

    Wang, Zhiwei; Li, Xiaoguang; Chen, Jin; Jin, Zhengyu; Shi, Haifeng; Zhang, Xiaobo; Pan, Jie; Liu, Wei; Yang, Ning; Chen, Jie

    2013-01-01

    To evaluate the value of computed tomography (CT)-guided core needle biopsy in diagnosis of primary pulmonary lymphoma and its subtypes. A retrospective analysis of the records of all patients with primary pulmonary lymphoma between January 2005 and August 2011 was performed. There were 25 patients referred to the radiology department for CT-guided core needle biopsy. The success rate and complications were assessed. A definitive diagnosis and accurate histologic subtype were obtained in 21 patients with a success rate of 84.0%. Diagnosis was made in the other four patients with bronchoscopy and surgery. Non-Hodgkin lymphoma (NHL) was the diagnosis in all patients. Most subtypes were mucosa-associated lymphoid tissue (MALT) lymphomas (n = 19). The remaining subtypes included three diffuse large B-cell NHLs, two peripheral T-cell lymphomas not otherwise specified, and one anaplastic large cell NHL. The success rate of core needle biopsy was 95% (18 of 19) for MALT lymphomas, 67% (2 of 3) for diffuse large B cell NHLs, and 33% (1 of 3) for other NHLs. The success rate for MALT lymphomas was significantly higher than that of non-MALT lymphomas according to Fisher exact t test (P = .031). No serious complications occurred in any patients. CT-guided core needle biopsy is a reliable procedure to assist in diagnosis and classification of primary pulmonary lymphomas, especially MALT lymphomas. Copyright © 2013 SIR. Published by Elsevier Inc. All rights reserved.

  2. Damage detection tomography based on guided waves in composite structures using a distributed sensor network

    Science.gov (United States)

    Memmolo, Vittorio; Maio, Leandro; Boffa, Natalino Daniele; Monaco, Ernesto; Ricci, Fabrizio

    2016-01-01

    Structural health monitoring (SHM) based on guided waves allows assessing the health of a structure due to the sensitivity to the occurrence of delamination. However, wave propagation presents several complexities for effective damage identification in composite structures. An efficient implementation of a guided wave-based SHM system requires an accurate analysis of collected data to obtain a useful detection. This paper is concerned with the identification of small emerging delaminations in composite structural components using a sparse array of surface ultrasonic transducers. An ultrasonic-guided wave tomography technique focused on impact damage detection in composite plate-like structures is presented. A statistical damage index approach is adopted to interpret the recorded signals, and a subsequent graphic interpolation is implemented to reconstruct the damage appearance. Experimental tests carried out on a typical composite structure demonstrated the effectiveness of the developed technique with the aim to investigate the presence and location of damage using simple imaging reports and a limited number of measurements. A traditional ultrasonic inspection (C-scan) is used to assess the methodology.

  3. 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

    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....... 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...... into Analyze7.0. In-house software, Landmarker, was applied to calculate the distance between two equal points on the superimposed 3D models. Fig. 1 exemplifies the results of the reconstructed root canals before and after instrumentation. In Fig. 2 the colour scale indicates increasing dentin removal during...

  4. Diagnostic accuracy of computed tomography-guided biopsy in pathological fractures.

    Science.gov (United States)

    Stokes, Christopher M; Elsewaisy, Osama; Pang, Grant; Slavin, John L; Schlicht, Stephen M; Choong, Peter F M

    2017-07-01

    Obtaining a histological diagnosis is essential for appropriate management of pathological fractures. Computed tomography (CT) is an accurate method of obtaining diagnosis for musculoskeletal tumours. We analysed whether diagnostic accuracy was maintained in the evaluation of pathological fractures. A retrospective review of 101 consecutive patients presenting to our tertiary musculoskeletal tumour centre with pathological fracture was performed. Patients underwent core needle biopsy under CT guidance of pathological fractures diagnosed by plain radiography and either CT or magnetic resonance imaging. The histopathology of the CT-guided biopsy was compared with the sample obtained from open biopsy or definitive surgery to determine diagnostic accuracy. The mean age at diagnosis was 52 ± 20 years (range: 18-85) in a cohort of 46 men and 55 women. Diagnostic accuracy of CT-guided biopsy was 82.18%. There were 65 malignant and 36 benign tumours with diagnostic accuracy of 86.15% and 80.56%, respectively. The positive predictive value for a malignant tumour was 98.21% whilst it was 93.1% for benign tumours. The femur (53 cases) and humerus (25 cases) were the commonest bones fractured. The most frequent diagnoses were metastasis (20.79%), giant cell tumour (17.82%), osteosarcoma (9.90%) and myeloma (9.90%). There were no complications of CT-guided biopsy. Pathological fracture does not confound the diagnosis of musculoskeletal tumours. CT-guided biopsy is an accurate diagnostic tool in the evaluation of pathological fractures. Final diagnosis and management should be made in the context of appropriate anatomical and functional imaging using a multidisciplinary approach. © 2017 Royal Australasian College of Surgeons.

  5. Imaging osteoarthritis in the knee joints using x-ray guided diffuse optical tomography

    Science.gov (United States)

    Zhang, Qizhi; Yuan, Zhen; Sobel, Eric S.; Jiang, Huabei

    2010-02-01

    In our previous studies, near-infrared (NIR) diffuse optical tomography (DOT) had been successfully applied to imaging osteoarthritis (OA) in the finger joints where significant difference in optical properties of the joint tissues was evident between healthy and OA finger joints. Here we report for the first time that large joints such as the knee can also be optically imaged especially when DOT is combined with x-ray tomosynthesis where the 3D image of the bones from x-ray is incorporated into the DOT reconstruction as spatial a priori structural information. This study demonstrates that NIR light can image large joints such as the knee in addition to finger joints, which will drastically broaden the clinical utility of our x-ray guided DOT technique for OA diagnosis.

  6. Functional morphology of the copulatory organs of a reed beetle and a shining leaf beetle (Coleoptera: Chrysomelidae: Donaciinae, Criocerinae) using X-ray micro-computed tomography *

    Science.gov (United States)

    Schmitt, Michael; Uhl, Gabriele

    2015-01-01

    Abstract For more than 100 years it has been known that the sclerotised median lobe of beetles harbours a membranous structure (the "internal sac" or "endophallus") which is everted during copula inside the female genital tract. In order to explore the functional role of this structure and those associated with it, we cryofixed copulating pairs of Donacia semicuprea and Lilioceris lilii and studied the relative position of the elements of the copulatory apparatus of males and females by micro-computer-tomography. We found that the everted endophallus fills the lumen of the bursa copulatrix completely. Our data suggest that in Lilioceris lilii the tip of the sclerotised distal part of the ejaculatory duct, the flagellum, is positioned exactly over the opening of the spermathecal duct inside the bursa copulatrix. The mouth of the bursa copulatrix in Donacia semicuprea is armed with a strong muscle ring, and the whole wall of the bursa is covered externally with a layer of muscle fibres. These morphological differences correspond with differences in mating behaviour: In reed beetles (Donaciinae), females seemingly can control mating to a higher degree than in lily beetles (Lilioceris spp.). PMID:26798321

  7. Localization of Metal Electrodes in the Intact Rat Brain Using Registration of 3D Microcomputed Tomography Images to a Magnetic Resonance Histology Atlas1,2,3

    Science.gov (United States)

    Borg, Jana Schaich; Vu, Mai-Anh; Badea, Cristian; Badea, Alexandra; Johnson, G. Allan

    2015-01-01

    Abstract Simultaneous neural recordings taken from multiple areas of the rodent brain are garnering growing interest because of the insight they can provide about spatially distributed neural circuitry. The promise of such recordings has inspired great progress in methods for surgically implanting large numbers of metal electrodes into intact rodent brains. However, methods for localizing the precise location of these electrodes have remained severely lacking. Traditional histological techniques that require slicing and staining of physical brain tissue are cumbersome and become increasingly impractical as the number of implanted electrodes increases. Here we solve these problems by describing a method that registers 3D computed tomography (CT) images of intact rat brains implanted with metal electrode bundles to a magnetic resonance imaging histology (MRH) atlas. Our method allows accurate visualization of each electrode bundle’s trajectory and location without removing the electrodes from the brain or surgically implanting external markers. In addition, unlike physical brain slices, once the 3D images of the electrode bundles and the MRH atlas are registered, it is possible to verify electrode placements from many angles by “reslicing” the images along different planes of view. Furthermore, our method can be fully automated and easily scaled to applications with large numbers of specimens. Our digital imaging approach to efficiently localizing metal electrodes offers a substantial addition to currently available methods, which, in turn, may help accelerate the rate at which insights are gleaned from rodent network neuroscience. PMID:26322331

  8. The using of megavoltage computed tomography in image-guided brachytherapy for cervical cancer: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Tharavichitkul, Ekkasit; Janla-or, Suwapim; Wanwilairat, Somsak; Chakrabandhu, Somvilai; Klunklin, Pitchayaponne; Onchan, Wimrak; Supawongwattana, Bongkot; Chitapanarux, Imjai [Division of Therapeutic Radiology and Oncology, Dept. of Radiology, Faculty of Medicine, Chiang Mai University, Chiang Mai (Thailand); Galalae, Razvan M. [Faculty of Medicine, Christian-Albrecht University (Campus Kiel), Kiel (Germany)

    2015-06-15

    We present a case of cervical cancer treated by concurrent chemoradiation. In radiation therapy part, the combination of the whole pelvic helical tomotherapy plus image-guided brachytherapy with megavoltage computed tomography of helical tomotherapy was performed. We propose this therapeutic approach could be considered in a curative setting in some problematic situation as our institution.

  9. Computed Tomography Guided Hook-wire Precise Localization and Minimally Invasive Resection of Pulmonary Nodules

    Directory of Open Access Journals (Sweden)

    Tong WANG

    2015-11-01

    Full Text Available Background and objective Localization of pulmonary ground glass nodule is the technical difficulty of minimally invasive operation resection. The aim of this study is to evaluate the value of computed tomography (CT-guided Hook-wire precise localization in resection of pulmonary nodules by video-assisted thoracoscopic surgery (VATS as well as to discuss the necessity and feasibility of surgical resection of GGOs through a minimally invasive approach. Methods CT-guided Hook-wire precise localization and wedge resection was done on 25 cases with 26 pulmonary nodules by VATS from May 2013 to June 2015. The efficacy of localization was evaluated in terms of procedure time, VATS success rate, and associated complications of localization. Results All the 26 pulmonary nodules (6 solid nodules and 20 GGOs of 25 patients (10 males and 15 females were preoperatively detected and localized with Hook-wire under CT guidance. Nodule diameters ranged from 5 mm-20 mm (mean: 8 mm. The distance of lung lesions from the nearest pleural surfaces ranged within 5 mm-30 mm (mean: 14 mm. All resections of lesions guided by the Hook-wire were successfully performed by VATS (success rate: 100%. The mean procedure time for the CT-guided Hook-wire localization was 10 min (range: 5 min-10 min. The mean procedure time for VATS wedge resection was 20 min (range: 15 min-40 min. The mean hospital time was 4 d (range: 3 d-6 d. The major complication of CT-guided Hook-wire localization was mild pneumothorax in 4 patients, but no one needed chest tube drainage. Wedge resection was performed successfully in all cases. The dislocation of Hook-wire was found in only one patient during the operation, but the lesion was still successfully resected under VATS. Results of pathological examination of 16 mGGOs revealed 8 primary lung cancers and 8 nonspecific chronic inflammations. Results of pathological examination of 4 pGGOs revealed 1 primary lung cancers, 1 atypical adenomatous

  10. Computer tomography urography assisted real-time ultrasound-guided percutaneous nephrolithotomy on renal calculus.

    Science.gov (United States)

    Fang, You-Qiang; Wu, Jie-Ying; Li, Teng-Cheng; Zheng, Hao-Feng; Liang, Guan-Can; Chen, Yan-Xiong; Hong, Xiao-Bin; Cai, Wei-Zhong; Zang, Zhi-Jun; Di, Jin-Ming

    2017-06-01

    This study aimed to assess the role of pre-designed route on computer tomography urography (CTU) in the ultrasound-guided percutaneous nephrolithotomy (PCNL) for renal calculus.From August 2013 to May 2016, a total of 100 patients diagnosed with complex renal calculus in our hospital were randomly divided into CTU group and control group (without CTU assistance). CTU was used to design a rational route for puncturing in CTU group. Ultrasound was used in both groups to establish a working trace in the operation areas. Patients' perioperative parameters and postoperative complications were recorded.All operations were successfully performed, without transferring to open surgery. Time of channel establishment in CTU group (6.5 ± 4.3 minutes) was shorter than the control group (10.0 ± 6.7 minutes) (P = .002). In addition, there was shorter operation time, lower rates of blood transfusion, secondary operation, and less establishing channels. The incidence of postoperative complications including residual stones, sepsis, severe hemorrhage, and perirenal hematoma was lower in CTU group than in control group.Pre-designing puncture route on CTU images would improve the puncturing accuracy, lessen establishing channels as well as improve the security in the ultrasound-guided PCNL for complex renal calculus, but at the cost of increased radiation exposure.

  11. Efficacy of computed tomography guided radiofrequency ablation forosteoid osteomas in 31 patients

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Hoon; Ahn, Joong Mo; Lee, Joon Woo; Lee, Guen Young; Lee, Eu Gene; Oh, Joo Han; Cho, Hwan Seong; Kang, Heung Sik [Seoul National University Bundang Hospital, Seongnam (Korea, Republic of)

    2015-04-15

    To present the clinical outcome of computed tomography (CT) guided radiofrequency ablation (RFA) for osteoid osteoma. Thirty-one patients (M:F = 23:8, mean age: 20 years, range: 4-54 years) who underwent RFA for clinically suspected osteoid osteoma from May 2004 to December 2013 were retrospectively reviewed. RFA was done in all cases under CT guidance by one of three radiologists in our department. Electronic medical records and images were retrospectively reviewed in all patients. Lesions were located in femur (n = 20), tibia (n = 5), fibula (n = 2), humerus (n = 3), talus (n = 2), and calcaneus (n = 1). On discharge, 27 of 33 cases showed complete remission of pain (82%). One major complication (compartment syndrome) and 2 minor complications (reactive synovitis, minimal skin burn at electrode insertion site) were observed. On the last follow-up (0-78 months, mean: 12.6 months) 27 of 33 cases were successfully treated (82%) and had no more complaints. 3 cases presented remaining pain (9%). In 3 cases relapse occurred (9%) and RFA was repeated in 1 case. The repeated treatment was successful. CT-guided RFA is an effective method for the treatment of osteoid osteoma.

  12. Radiation dose reduction in computed tomography-guided lung interventions using an iterative reconstruction technique

    Energy Technology Data Exchange (ETDEWEB)

    Chang, D.H.; Hiss, S.; Borggrefe, J.; Bunck, A.C.; Maintz, D.; Hackenbroch, M. [Cologne University Hospital (Germany). Dept. of Radiology; Mueller, D. [Clinical Science Philips Healthcare GmbH, Munich (Germany). Clinical Science; Hellmich, M. [Cologne University Hospital (Germany). Inst. of Medical Statistics, Informatics and Epidemiology

    2015-10-15

    To compare the radiation doses and image qualities of computed tomography (CT)-guided interventions using a standard-dose CT (SDCT) protocol with filtered back projection and a low-dose CT (LDCT) protocol with both filtered back projection and iterative reconstruction. Image quality and radiation doses (dose-length product and CT dose index) were retrospectively reviewed for 130 patients who underwent CT-guided lung interventions. SDCT at 120 kVp and automatic mA modulation and LDCT at 100 kVp and a fixed exposure were each performed for 65 patients. Image quality was objectively evaluated as the contrast-to-noise ratio and subjectively by two radiologists for noise impression, sharpness, artifacts and diagnostic acceptability on a four-point scale. The groups did not significantly differ in terms of diagnostic acceptability and complication rate. LDCT yielded a median 68.6 % reduction in the radiation dose relative to SDCT. In the LDCT group, iterative reconstruction was superior to filtered back projection in terms of noise reduction and subjective image quality. The groups did not differ in terms of beam hardening artifacts. LDCT was feasible for all procedures and yielded a more than two-thirds reduction in radiation exposure while maintaining overall diagnostic acceptability, safety and precision. The iterative reconstruction algorithm is preferable according to the objective and subjective image quality analyses.

  13. THREE-DIMENSIONAL COMPUTED TOMOGRAPHY-GUIDED RADIOFREQUENCY TRIGEMINAL RHIZOTOMY FOR TREATMENT OF IDIOPATHIC TRIGEMINAL NEURALGIA

    Institute of Scientific and Technical Information of China (English)

    Meng Liu; Cheng-yuan Wu; Yu-guang Liu; Hong-wei Wang; Fan-gang Meng

    2005-01-01

    Objective To evaluate the effectiveness of three-dimensional computed tomography (3D-CT) guided radiofrequency trige minal rhizotomy (RF-TR) in treatment of idiopathic trigeminal neuralgia (ITN). Methods From 1999 to 2001, 18 patients with ITN were treated with percutaneous controlled RF-TR. Intraoperative 3D-CT scanning was performed to guide the trajectory of the puncture. After correction of the needle tip according to the CT scans and stimulation effects, 2 to 5 lesions were made for a duration of 60-90 seconds at a temperature of 60℃ to 75℃ depend ing on the pain distribution and the age of patient. Results The needles located in foramen ovale. Pain alleviated immediately with no serious complication in all patients. The patients were followed up for an average of 31.5 months (range 24-41 months). Acute pain relief was experienced by 17 patients after the procedure, reaching an initial success rate of 94.4%. Early (< 6 months) pain recurrence was observed in 2 patients (11.1%), whereas late (> 6 months) recurrence was reported in 3 patients (16.7%). Thirteen patients had complete pain control, with no need for medication thereafter. Five cases experienced partial pain relief, but required medication at a lower dose than in the preoperative period. Conclusion 3D-CT foramen ovale locations can raise the successful rate of puncture, enhance the safety, and reduce the incidence rate of complication.

  14. Computed tomography-guided percutaneous catheter drainage of primary and secondary iliopsoas abscesses

    Energy Technology Data Exchange (ETDEWEB)

    Cantasdemir, M. E-mail: cantas1@yahoo.com; Kara, B.; Cebi, D.; Selcuk, N.D.; Numan, F

    2003-10-01

    AIM: To report our experience with computed tomography (CT)-guided percutaneous catheter drainage (PCD) of iliopsoas abscesses. MATERIALS AND METHODS: Twenty-two iliopsoas abscesses in 21 patients (11 women, 10 men) aged between 18 and 66 years (mean 36 years) were treated with PCD. Abdominal CT demonstrated the iliopsoas abscesses, which were definitively determined by Gram staining and aspirate cultures. Twenty of the 22 iliopsoas abscesses were primary and two were secondary. All PCD procedures were performed under local anaesthesia using a single-step trocar technique (n=19) or Seldinger technique (n=3). RESULTS: PCD was an effective treatment in 21 out of the 22 iliopsoas abscesses. Recurrence was seen in three abscesses as minimal residual collections. Two of them resolved spontaneously with anti-tuberculous regimen. One required percutaneous needle aspiration. The procedure failed in a diabetic patient with a secondary abscess, who died due to sepsis. The length of time that catheters remained in place ranged from 21 to 75 days (mean 59.7 days). Complications included catheter dislocation in four abscesses, which required removal of dislocated catheters and indwelling new ones. CONCLUSION: CT-guided PCD is a safe and effective front-line treatment of iliopsoas abscesses. Surgery should be reserved for failure of PCD and presence of contraindications to PCD.

  15. [Clinical application of sinus floor elevation guided by cone-beam computer tomography].

    Science.gov (United States)

    Zhou, Wen-qing; Chen, Jan-rong; Zhou, Yong-qiang; Wu, Yan-ping; Chen, Lu; Ding, Shui-qing

    2014-02-01

    To investigate the value of using con-beam computer tomography (CBCT) to evaluate bone volume in the edentulous area of posterior maxilla, and guide sinus floor elevation. Twenty eight patients who planed to receive dental implant in the posterior maxilla underwent CBCT scan. After analysis of residual bone height, 19 patients with 5-10 mm bone height below the sinus floor underwent transcrestal sinus floor elevation, while 7 patients with less than 5 mm bone height below the sinus floor underwent lateral window sinus floor elevation. The treatment outcomes were assessed postoperatively. CBCT detected bone deficiency in the posterior maxillary alveolar bone in 26 patients, mucus cyst of maxillary sinus in 1 patient and sinus septa in 2 patients. Nineteen patients underwent transcrestal sinus floor elevation, and 7 patients underwent lateral window sinus floor elevation. All patients completed final dental restorations, and the restorations achieved satisfactory function and esthetic. CBCT imaging plays an important role in determining bone quality in posterior maxilla and guiding sinus floor elevation. Supported by Social Undertakings Technological Innovation and Demonstration Program of Nantong City (HS2011035).

  16. Just-in-time tomography (JiTT): a new concept for image-guided radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Pang, G; Rowlands, J A [Toronto-Sunnybrook Regional Cancer Centre, 2075 Bayview Avenue, Toronto M4N 3M5 (Canada); Imaging Research, Sunnybrook and Women' s College Health Sciences Centre, Departments of Radiation Oncology and Medical Biophysics, University of Toronto, Toronto (Canada)

    2005-11-07

    Soft-tissue target motion is one of the main concerns in high-precision radiation therapy. Cone beam computed tomography (CBCT) has been developed recently to image soft-tissue targets in the treatment room and guide the radiation therapy treatment. However, due to its relatively long image acquisition time the CBCT approach cannot provide images of the target at the instant of the treatment and thus it is not adequate for imaging targets with intrafraction motion. In this note, a new approach for image-guided radiation therapy-just-in-time tomography (JiTT)-is proposed. Differing from CBCT, JiTT takes much less time to generate the needed tomographical, beam's-eye-view images of the treatment target at the right moment to guide the radiation therapy treatment. (note)

  17. Teaching with Microcomputers.

    Science.gov (United States)

    Gerber, Michael M.

    1986-01-01

    The introduction to the special section on microcomputers in special education reviews the trend toward increasing computer use, raises such issues as the need for special educators to provide leadership in the use of computers for individualized instruction, and summarizes remaining articles in the section. (DB)

  18. Computed tomography guided needle biopsy: experience from 1,300 procedures

    Energy Technology Data Exchange (ETDEWEB)

    Chojniak, Rubens; Isberner, Rony Klaus; Viana, Luciana Marinho; Yu, Liao Shin; Aita, Alessandro Amorim; Soares, Fernando Augusto [Hospital do Cancer A.C. Camargo, Sao Paulo, SP (Brazil). Dept. de Radiologia e Patologia

    2006-01-15

    Context and objective: computed tomography (CT) guided biopsy is widely accepted as effective and safe for diagnosis in many settings. Accuracy depends on target organ and needle type. Cutting needles present advantages over fine needles. This study presents experience from CT guided biopsies performed at an oncology center. Design and setting: retrospective study at Hospital do Cancer A. C. Camargo, Sao Paulo.Methods: 1,300 consecutive CT guided biopsies performed between July 1994 and February 2000 were analyzed. Nodules or masses were suspected as primary malignancy in 845 cases (65%) or metastatic lesion in 455 (35%). 628 lesions were thoracic, 281 abdominal, 208 retroperitoneal, 134 musculoskeletal and 49 head/neck. All biopsies were performed by one radiologist or under his supervision: 765 (59%) with 22-gauge fine-needle/aspiration technique and 535 (41%) with automated 16 or 18-gauge cutting-needle biopsy. Results: adequate samples were obtained in 70-92% of fine-needle and 93-100% of cutting-needle biopsies. The specific diagnosis rates were 54-67% for fine-needle and 82-100% for cutting-needle biopsies, according to biopsy site. For any site, sample adequacy and specific diagnosis rate were always better for cutting-needle biopsy. Among 530 lung biopsies, there were 84 pneumothorax (16%) and two hemothorax (0.3%) cases, with thoracic drainage in 24 (4.9%). Among abdominal and retroperitoneal biopsies, there were two cases of major bleeding and one of peritonitis. Conclusion: both types of needle showed satisfactory results, but cutting-needle biopsy should be used when specific diagnosis is desired without greater incidence of complications. (author)

  19. Success rates for computed tomography-guided musculoskeletal biopsies performed using a low-dose technique

    Energy Technology Data Exchange (ETDEWEB)

    Motamedi, Kambiz; Levine, Benjamin D.; Seeger, Leanne L.; McNitt-Gray, Michael F. [UCLA Health System, Radiology, Los Angeles, CA (United States)

    2014-11-15

    To evaluate the success rate of a low-dose (50 % mAs reduction) computed tomography (CT) biopsy technique. This protocol was adopted based on other successful reduced-CT radiation dose protocols in our department, which were implemented in conjunction with quality improvement projects. The technique included a scout view and initial localizing scan with standard dose. Additional scans obtained for further guidance or needle adjustment were acquired by reducing the tube current-time product (mAs) by 50 %. The radiology billing data were searched for CT-guided musculoskeletal procedures performed over a period of 8 months following the initial implementation of the protocol. These were reviewed for the type of procedure and compliance with the implemented protocol. The compliant CT-guided biopsy cases were then retrospectively reviewed for patient demographics, tumor pathology, and lesion size. Pathology results were compared to the ultimate diagnoses and were categorized as diagnostic, accurate, or successful. Of 92 CT-guided procedures performed during this period, two were excluded as they were not biopsies (one joint injection and one drainage), 19 were excluded due to non-compliance (operators neglected to follow the protocol), and four were excluded due to lack of available follow-up in our electronic medical records. A total of 67 compliant biopsies were performed in 63 patients (two had two biopsies, and one had three biopsies). There were 32 males and 31 females with an average age of 50 (range, 15-84 years). Of the 67 biopsies, five were non-diagnostic and inaccurate and thus unsuccessful (7 %); five were diagnostic but inaccurate and thus unsuccessful (7 %); 57 were diagnostic and accurate thus successful (85 %). These results were comparable with results published in the radiology literature. The success rate of CT-guided biopsies using a low-dose protocol is comparable to published rates for conventional dose biopsies. The implemented low-dose protocol

  20. Multi-projection bioluminescence tomography guided system for small animal radiation research platform (SARRP)

    Science.gov (United States)

    Zhang, Bin; Iordachita, Iulian; Wong, John W.; Wang, Ken Kang-Hsin

    2016-03-01

    Cone beam computed tomography (CBCT) is limited in guiding irradiation for soft tissue targets. As a complementary imaging modality, bioluminescence tomography (BLT) provides strong soft tissue contrast. We developed a dual-use BLT system which consists of an optical assembly, a mobile cart and an independent mouse bed. The system is motorized which can easily dock onto an independent mouse bed operating as a standalone system for longitudinal bioluminescence imaging (BLI)/BLT studies and also dock onto the SARRP for on-line radiation guidance. Our initial tests for the system demonstrate that (i) the imaging depth is 28 mm, (ii) the optical background is sufficiently low and uniform, (iii) the non-uniform response of the optical imaging can be corrected by the flat field correction, and (iv) the imaging acquisition speed was improved by an average of 3.7 times faster than our previous systems. We also presented a geometry calibration procedure to map the planar BLIs acquired at multi-projections onto the surface of the CBCT image. The CBCT is required to generate the mesh for BLT reconstruction and used for treatment planning and radiation delivery. Feasibility study of the geometry calibration was performed on a manual-docking prototype. The mean and maximum mapping accuracy is 0.3 and 0.6 mm. The performance of the proposed motorized dual-use system is expected to be superior to that of the manual-docking prototype because of the mechanism stability. We anticipate the dual-use system as a highly efficient and cost-effective platform to facilitate optical imaging for preclinical radiation research.

  1. Dual source and dual detector arrays tetrahedron beam computed tomography for image guided radiotherapy

    Science.gov (United States)

    Kim, Joshua; Lu, Weiguo; Zhang, Tiezhi

    2014-02-01

    Cone-beam computed tomography (CBCT) is an important online imaging modality for image guided radiotherapy. But suboptimal image quality and the lack of a real-time stereoscopic imaging function limit its implementation in advanced treatment techniques, such as online adaptive and 4D radiotherapy. Tetrahedron beam computed tomography (TBCT) is a novel online imaging modality designed to improve on the image quality provided by CBCT. TBCT geometry is flexible, and multiple detector and source arrays can be used for different applications. In this paper, we describe a novel dual source-dual detector TBCT system that is specially designed for LINAC radiation treatment machines. The imaging system is positioned in-line with the MV beam and is composed of two linear array x-ray sources mounted aside the electrical portal imaging device and two linear arrays of x-ray detectors mounted below the machine head. The detector and x-ray source arrays are orthogonal to each other, and each pair of source and detector arrays forms a tetrahedral volume. Four planer images can be obtained from different view angles at each gantry position at a frame rate as high as 20 frames per second. The overlapped regions provide a stereoscopic field of view of approximately 10-15 cm. With a half gantry rotation, a volumetric CT image can be reconstructed having a 45 cm field of view. Due to the scatter rejecting design of the TBCT geometry, the system can potentially produce high quality 2D and 3D images with less radiation exposure. The design of the dual source-dual detector system is described, and preliminary results of studies performed on numerical phantoms and simulated patient data are presented.

  2. Dual source and dual detector arrays tetrahedron beam computed tomography for image guided radiotherapy.

    Science.gov (United States)

    Kim, Joshua; Lu, Weiguo; Zhang, Tiezhi

    2014-02-01

    Cone-beam computed tomography (CBCT) is an important online imaging modality for image guided radiotherapy. But suboptimal image quality and the lack of a real-time stereoscopic imaging function limit its implementation in advanced treatment techniques, such as online adaptive and 4D radiotherapy. Tetrahedron beam computed tomography (TBCT) is a novel online imaging modality designed to improve on the image quality provided by CBCT. TBCT geometry is flexible, and multiple detector and source arrays can be used for different applications. In this paper, we describe a novel dual source-dual detector TBCT system that is specially designed for LINAC radiation treatment machines. The imaging system is positioned in-line with the MV beam and is composed of two linear array x-ray sources mounted aside the electrical portal imaging device and two linear arrays of x-ray detectors mounted below the machine head. The detector and x-ray source arrays are orthogonal to each other, and each pair of source and detector arrays forms a tetrahedral volume. Four planer images can be obtained from different view angles at each gantry position at a frame rate as high as 20 frames per second. The overlapped regions provide a stereoscopic field of view of approximately 10-15 cm. With a half gantry rotation, a volumetric CT image can be reconstructed having a 45 cm field of view. Due to the scatter rejecting design of the TBCT geometry, the system can potentially produce high quality 2D and 3D images with less radiation exposure. The design of the dual source-dual detector system is described, and preliminary results of studies performed on numerical phantoms and simulated patient data are presented.

  3. Computed-tomography-guided anatomic standardization for quantitative assessment of dopamine transporter SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Yokoyama, Kota [National Center of Neurology and Psychiatry, Department of Radiology, Tokyo (Japan); National Center of Neurology and Psychiatry, Integrative Brain Imaging Center, Tokyo (Japan); Imabayashi, Etsuko; Matsuda, Hiroshi [National Center of Neurology and Psychiatry, Integrative Brain Imaging Center, Tokyo (Japan); Sumida, Kaoru; Sone, Daichi; Kimura, Yukio; Sato, Noriko [National Center of Neurology and Psychiatry, Department of Radiology, Tokyo (Japan); Mukai, Youhei; Murata, Miho [National Center of Neurology and Psychiatry, Department of Neurology, Tokyo (Japan)

    2017-03-15

    For the quantitative assessment of dopamine transporter (DAT) using [{sup 123}I]FP-CIT single-photon emission computed tomography (SPECT) (DaTscan), anatomic standardization is preferable for achieving objective and user-independent quantification of striatal binding using a volume-of-interest (VOI) template. However, low accumulation of DAT in Parkinson's disease (PD) would lead to a deformation error when using a DaTscan-specific template without any structural information. To avoid this deformation error, we applied computed tomography (CT) data obtained using SPECT/CT equipment to anatomic standardization. We retrospectively analyzed DaTscan images of 130 patients with parkinsonian syndromes (PS), including 80 PD and 50 non-PD patients. First we segmented gray matter from CT images using statistical parametric mapping 12 (SPM12). These gray-matter images were then anatomically standardized using the diffeomorphic anatomical registration using exponentiated Lie algebra (DARTEL) algorithm. Next, DaTscan images were warped with the same parameters used in the CT anatomic standardization. The target striatal VOIs for decreased DAT in PD were generated from the SPM12 group comparison of 20 DaTscan images from each group. We applied these VOIs to DaTscan images of the remaining patients in both groups and calculated the specific binding ratios (SBRs) using nonspecific counts in a reference area. In terms of the differential diagnosis of PD and non-PD groups using SBR, we compared the present method with two other methods, DaTQUANT and DaTView, which have already been released as software programs for the quantitative assessment of DaTscan images. The SPM12 group comparison showed a significant DAT decrease in PD patients in the bilateral whole striatum. Of the three methods assessed, the present CT-guided method showed the greatest power for discriminating PD and non-PD groups, as it completely separated the two groups. CT-guided anatomic standardization using

  4. Role of Manual Aspiration in Treating Pneumothorax after Computed Tomography-Guided Lung Biopsy

    Energy Technology Data Exchange (ETDEWEB)

    Yamagami, T.; Terayama, K.; Yoshimatsu, R.; Matsumoto, T.; Miura, H.; Nishimura, T. (Dept. of Radiology, Graduate School of Medical Science, Kyoto Prefectural Univ. of Medicine, Kyoto (Japan)). e-mail: yamagami@koto.kpu-m.ac.jp

    2009-12-15

    Background: Pneumothorax is the most common complication after computed tomography (CT)-guided lung biopsy. The presence of a pneumothorax per se does not complicate patient management, but an increasing pneumothorax, making chest tube placement necessary, is highly problematic. Purpose: To evaluate the efficacy and limitations of simple aspiration of air from the pleural space to prevent increased pneumothorax and avoid chest tube placement in cases of pneumothorax following CT-guided lung biopsy. Material and Methods: The subjects of our study were 642 consecutive lung lesions in 594 patients for which percutaneous needle lung biopsies were performed using CT guidance. While patients were on the CT scanner table, percutaneous manual aspiration was performed in all patients with a non-small pneumothorax demonstrated on post-biopsy chest CT images. The frequency of pneumothorax, management of each such case, and factors influencing the incidence of worsening pneumothorax that finally required chest tube placement were evaluated. Results: Post-biopsy pneumothorax occurred in 243 of 642 (38%) procedures. Of the 243 cases, 112 were treated with manual aspiration immediately after biopsy. In 210 (86.4%), the pneumothorax had resolved completely on follow-up chest radiographs without chest tube placement. Only 33 patients required chest tube placement. Requirement of chest tube insertion significantly increased in parallel with the degree of pneumothorax as shown on post-biopsy CT images. The rate of chest tube insertion was statistically higher in subjects with values for aspirated air above 543 ml. Conclusion: Percutaneous manual aspiration of biopsy-induced pneumothorax performed immediately after biopsy may prevent worsening of pneumothorax and avoid chest tube placement. The amount of aspirated air can be predictive of the requirement for chest tube placement

  5. Image-guided modified deep anterior lamellar keratoplasty (DALK) corneal transplant using intraoperative optical coherence tomography

    Science.gov (United States)

    Tao, Yuankai K.; LaBarbera, Michael; Ehlers, Justis P.; Srivastava, Sunil K.; Dupps, William J.

    2015-03-01

    Deep anterior lamellar keratoplasty (DALK) is an alternative to full-thickness corneal transplant and has advantages including the absence of allograft rejection; shortened duration of topical corticosteroid treatment and reduced associated risk of glaucoma, cataract, or infection; and enables use of grafts with poor endothelial quality. DALK begins by performing a trephination of approximately 80% stromal thickness, as measured by pachymetry. After removal of the anterior stoma, a needle is inserted into the residual stroma to inject air or viscoelastic to dissect Descemet's membrane. These procedures are inherently difficult and intraoperative rates of Descemet's membrane perforation between 4-39% have been reported. Optical coherence tomography (OCT) provides high-resolution images of tissue microstructures in the cornea, including Descemet's membrane, and allows quantitation of corneal layer thicknesses. Here, we use crosssectional intraoperative OCT (iOCT) measurements of corneal thickness during surgery and a novel micrometeradjustable biopsy punch to precision-cut the stroma down to Descemet's membrane. Our prototype cutting tool allows us to establish a dissection plane at the corneal endothelium interface, mitigates variability in cut-depths as a result of tremor, reduces procedure complexity, and reduces complication rates. iOCT-guided modified DALK procedures were performed on 47 cadaveric porcine eyes by non-experts and achieved a perforation rate of ~5% with a mean corneal dissection time <18 minutes. The procedure was also successful performed on a human donor eye without perforation. Our data shows the potential for iOCT-guided precision anterior segment surgery without variability as a result of tremor and improvements to standard clinical care.

  6. Preoperative computed tomography-guided percutaneous localization of ground glass pulmonary opacity with polylactic acid injection.

    Science.gov (United States)

    Hu, Mu; Zhi, Xiuyi; Zhang, Jian

    2015-07-01

    Localization of a ground glass nodule is a difficult challenge for thoracic surgeons, especially for ground glass opacities (GGOs) less than 10 mm in diameter. In this study we implement a new method for preoperative localization of pulmonary (GGOs). From October 2013 to December 2014, computed tomography-guided percutaneous polylactic acid injection localizations were performed for five pulmonary nodules in five patients (2 men and 3 women; mean age, 59.8 years; range, 54-65 years). The injection was feasible in all patients and the localization effect was excellent. The total procedure duration was 12.6 minutes (range; 10-15) and the volume of polylactic acid injected was 0.38 mL. The wedge resections were easily and successfully performed in all five cases. The cutting margin was no less than 2 cm from the lesion. This technique is promising for the determination of GGO location in thoracoscopic surgery for wedge resection.

  7. Light-emitting diode-based multiwavelength diffuse optical tomography system guided by ultrasound

    Science.gov (United States)

    Yuan, Guangqian; Alqasemi, Umar; Chen, Aaron; Yang, Yi; Zhu, Quing

    2014-01-01

    Abstract. Laser diodes are widely used in diffuse optical tomography (DOT) systems but are typically expensive and fragile, while light-emitting diodes (LEDs) are cheaper and are also available in the near-infrared (NIR) range with adequate output power for imaging deeply seated targets. In this study, we introduce a new low-cost DOT system using LEDs of four wavelengths in the NIR spectrum as light sources. The LEDs were modulated at 20 kHz to avoid ambient light. The LEDs were distributed on a hand-held probe and a printed circuit board was mounted at the back of the probe to separately provide switching and driving current to each LED. Ten optical fibers were used to couple the reflected light to 10 parallel photomultiplier tube detectors. A commercial ultrasound system provided simultaneous images of target location and size to guide the image reconstruction. A frequency-domain (FD) laser-diode-based system with ultrasound guidance was also used to compare the results obtained from those of the LED-based system. Results of absorbers embedded in intralipid and inhomogeneous tissue phantoms have demonstrated that the LED-based system provides a comparable quantification accuracy of targets to the FD system and has the potential to image deep targets such as breast lesions. PMID:25473884

  8. Optical coherence tomography for image-guided dermal filler injection and biomechanical evaluation

    Science.gov (United States)

    Singh, Manmohan; Wang, Shang; Yee, Richard W.; Han, Zhaolong; Aglyamov, Salavat R.; Larin, Kirill V.

    2017-02-01

    Dermal fillers are a very popular anti-ag ing treatment with estimated sales in the billions of dollars and millions of procedures performed. As the aging population continues to grow, these figures are only e xpected to increase. Dermal fillers have various compositions depending on their intended applicati on. Reactions to dermal fillers can be severe, such as ischemic events and filler migration to the eyes. Howe ver, these adverse reactions are rare. Nevertheless, the capability to perform imag e-guided filler injections would minimize th e risk of such reacti ons. In addition, the biomechanical properties of various fillers have been evalua ted, but there has been no investigation on the effects of filler on the biomechanical properties of skin. In this work, we utilize optical cohe rence tomography (OCT) for visualizing dermal filler injections with micrometer-scale sp atial resolution. In addition, we utilize noncontact optical coherence elastography (OCE) to quantify the changes in the biomechan ical properties of pig skin after the dermal filler injections. OCT was successfully able to visualize the dermal filler injecti on process, and OCE showed that the viscoelasticity of the pig skin was increased locally at the filler injection sites. OCT may be able to provide real-time image guidance in 3D, and when combined with functional OCT techniques such as optical microangiography, could be used to avoid blood vessels during the injection.

  9. Cone-beam computed tomography as a surgical guide to impacted anterior teeth

    Directory of Open Access Journals (Sweden)

    Fabiano Jeremias

    2016-01-01

    Full Text Available Surgical procedure for removal of impacted teeth is a challenge for clinicians as it involves accuracy in the diagnosis and localization of the dental elements. The cone-beam computed tomography (CBCT, compared to the conventional radiography, has a greater potential to provide complementary information because of its three-dimensional (3D images, reducing the possibility of failures in surgical procedures. Two 10-year-old boys presented with aesthetic issues associated with the juxtaposition of ectopic teeth with the permanent ones. Both two-dimensional and 3D preoperative radiographic diagnostic sets were produced. The occlusal and panoramic radiographs were not enough for proper localization of impacted incisors. Thus, the CBCT was used as a surgical guide. After 2 years of longitudinal following, no lesion was recorded, and the orthodontic treatment has proven successful. In all cases, CBCT contributed to both diagnosis and correct localization of supernumerary teeth, aiding the professional in the treatment planning, and consequently in the clinical success. The surgeries were completely safe, avoiding damage in noble structures, and providing a better recovering of the patients.

  10. The Microcomputer in the Library: I. Introduction.

    Science.gov (United States)

    Leggate, Peter; Dyer, Hilary

    1985-01-01

    This first in a series of six articles introducing microcomputer applications in smaller libraries discusses microcomputer components (hardware, operating systems, applications software); microcomputer history; current hardware; library applications; performance criteria; factors influencing performance; integrated systems; information retrieval;…

  11. Role of microcomputed tomography in microvascular imaging

    Science.gov (United States)

    Ritman, Erik L.

    2011-03-01

    Micro-CT scans generate three-dimensional images consisting of the order of 10003 voxels (3D picture elements), each cubic voxel being sub-micron to 100 micrometer on a side. The gray-scale modulation within tomographic images reflects the local attenuation of the x-ray. This allows for differentiation of different tissues by virtue of their elemental content. However, the elements in blood vessel walls and within blood differ little from organ parenchyma, hence they are not readily distinguishable unless the attenuation of blood is enhanced by injecting a heavy element (such as iodine) into the blood stream or by staining the vessel wall tissues with heavy metals such as osmium tetroxide. Three-dimensional micro-CT images a volume (of light-opaque tissue) large enough to include entire, intact, vascular trees without the need to destroy the 3D tissue specimen. Hence, the fluid dynamic and the perfusion territory size consequences, as well the micro-anatomic relationship of the vascular branching geometry and interconnectivity to parenchymal structures (e.g., nephron, hepatic lobule or cancer) can be readily appreciated and quantified. The permeability of microvasculature can also be imaged by virtue of the increased contrast resulting from the fraction of the injected contrast agent passing through the endothelium into the surrounding extravascular tissue. In recent years micro-CT based on the imaging of coherent x-ray scatter and on x-ray phase shift caused by local electron density distributions (reflecting molecular bond type in some cases) provide greater inherent image contrast than does x-ray attenuation. These new capabilities are now active avenues of research and development.

  12. Pancreatic trauma: The role of computed tomography for guiding therapeutic approach

    Institute of Scientific and Technical Information of China (English)

    Marco; Moschetta; Michele; Telegrafo; Valeria; Malagnino; Laura; Mappa; Amato; A; Stabile; Ianora; Dario; Dabbicco; Antonio; Margari; Giuseppe; Angelelli

    2015-01-01

    AIM: To evaluate the role of computed tomography(CT) for diagnosing traumatic injuries of the pancreas and guiding the therapeutic approach.METHODS: CT exams of 6740 patients admitted to our Emergency Department between May 2005 and January 2013 for abdominal trauma were retrospectively evaluated. Patients were identified through a search of our electronic archive system by using such terms as "pancreatic injury", "pancreatic contusion", "pancreatic laceration", "peri-pancreatic fluid", "pancreatic active bleeding". All CT examinations were performed before and after the intravenous injection of contrast material using a 16-slice multidetector row computed tomography scanner. The data sets were retrospectively analyzed by two radiologists in consensus searching for specific signs of pancreatic injury(parenchymal fracture and laceration, focal or diffuse pancreatic enlargement/edema, pancreatic hematoma, active bleeding, fluid between splenic vein and pancreas) and non-specific signs(inflammatory changes in peri-pancreatic fat and mesentery, fluid surrounding the superior mesentericartery, thickening of the left anterior renal fascia, pancreatic ductal dilatation, acute pseudocyst formation/peri-pancreatic fluid collection, fluid in the anterior and posterior pararenal spaces, fluid in transverse mesocolon and lesser sac, hemorrhage into peri-pancreatic fat, mesocolon and mesentery, extraperitoneal fluid, intraperitoneal fluid).RESULTS: One hundred and thirty-six/Six thousand seven hundred and forty(2%) patients showed CT signs of pancreatic trauma. Eight/one hundred and thirty-six(6%) patients underwent surgical treatment and the pancreatic injures were confirmed in all cases. Only in 6/8 patients treated with surgical approach, pancreatic duct damage was suggested in the radiological reports and surgically confirmed in all cases. In 128/136(94%) patients who underwent non-operative treatment CT images showed pancreatic edema in 97 patients, hematoma in 31 patients

  13. A General Introduction to Microcomputers.

    Science.gov (United States)

    Muiznieks, Viktors

    This basic introduction to microcomputers provides the neophyte with the terminology, definitions, and concepts that explain the microcomputer and computing technology in general. Mathematical operations with binary numbers, computer storage, controlling logic, and the concepts of stack and interrupt are explained. (RAO)

  14. Trends In Microcomputer Image Processing

    Science.gov (United States)

    Strum, William E.

    1988-05-01

    We have seen, in the last four years, the microcomputer become the platform of choice for many image processing applications. By 1991, Frost and Sullivan forecasts that 75% of all image processing will be carried out on microcomputers. Many factors have contributed to this trend and will be discussed in the following paper.

  15. Results from percutaneous drainage of Hinchey stage II diverticulitis guided by computed tomography scan.

    Science.gov (United States)

    Durmishi, Y; Gervaz, P; Brandt, D; Bucher, P; Platon, A; Morel, P; Poletti, P A

    2006-07-01

    Percutaneous abscess drainage guided by computed tomography scan is considered the initial step in the management of patients presenting with Hinchey II diverticulitis. The rationale behind this approach is to manage the septic complication conservatively and to follow this later using elective sigmoidectomy with primary anastomosis. The clinical outcomes for Hinchey II patients who underwent percutaneous abscess drainage in our institution were reviewed. Drainage was considered a failure when signs of continuing sepsis developed, abscess or fistula recurred within 4 weeks of drainage, and emergency surgical resection with or without a colostomy had to be performed. A total of 34 patients (17 men and 17 women; median age, 71 years; range, 34-90 years) were considered for analysis. The median abscess size was 6 cm (range, 3-18 cm), and the median duration of drainage was 8 days (range, 1-18 days). Drainage was considered successful for 23 patients (67%). The causes of failure for the remaining 11 patients included continuing sepsis (n = 5), abscess recurrence (n = 5), and fistula formation (n = 1). Ten patients who failed percutaneous abscess drainage underwent an emergency Hartmann procedure, with a median delay of 14 days (range, 1-65 days) between drainage and surgery. Three patients in this group (33%) died in the immediate postoperative period. Among the 23 patients successfully drained, 12 underwent elective sigmoid resection with a primary anastomosis. The median delay between drainage and surgery was 101 days (range, 40-420 days). In this group, there were no anastomotic leaks and no mortality. Drainage of Hinchey II diverticulitis guided by computed scan was successful in two-thirds of the cases, and 35% of the patients eventually underwent a safe elective sigmoid resection with primary anastomosis. By contrast, failure of percutaneous abscess drainage to control sepsis is associated with a high mortality rate when an emergency resection is performed. The

  16. Evaluation of a cone beam computed tomography geometry for image guided small animal irradiation.

    Science.gov (United States)

    Yang, Yidong; Armour, Michael; Wang, Ken Kang-Hsin; Gandhi, Nishant; Iordachita, Iulian; Siewerdsen, Jeffrey; Wong, John

    2015-07-01

    The conventional imaging geometry for small animal cone beam computed tomography (CBCT) is that a detector panel rotates around the head-to-tail axis of an imaged animal ('tubular' geometry). Another unusual but possible imaging geometry is that the detector panel rotates around the anterior-to-posterior axis of the animal ('pancake' geometry). The small animal radiation research platform developed at Johns Hopkins University employs the pancake geometry where a prone-positioned animal is rotated horizontally between an x-ray source and detector panel. This study is to assess the CBCT image quality in the pancake geometry and investigate potential methods for improvement. We compared CBCT images acquired in the pancake geometry with those acquired in the tubular geometry when the phantom/animal was placed upright simulating the conventional CBCT geometry. Results showed signal-to-noise and contrast-to-noise ratios in the pancake geometry were reduced in comparison to the tubular geometry at the same dose level. But the overall spatial resolution within the transverse plane of the imaged cylinder/animal was better in the pancake geometry. A modest exposure increase to two folds in the pancake geometry can improve image quality to a level close to the tubular geometry. Image quality can also be improved by inclining the animal, which reduces streak artifacts caused by bony structures. The major factor resulting in the inferior image quality in the pancake geometry is the elevated beam attenuation along the long axis of the phantom/animal and consequently increased scatter-to-primary ratio in that orientation. Not withstanding, the image quality in the pancake-geometry CBCT is adequate to support image guided animal positioning, while providing unique advantages of non-coplanar and multiple mice irradiation. This study also provides useful knowledge about the image quality in the two very different imaging geometries, i.e. pancake and tubular geometry, respectively.

  17. Preliminary results of miniaturized and robust ultrasound guided diffuse optical tomography system for breast cancer detection

    Science.gov (United States)

    Vavadi, Hamed; Mostafa, Atahar; Li, Jinglong; Zhou, Feifei; Uddin, Shihab; Xu, Chen; Zhu, Quing

    2017-02-01

    According to the World Health Organization, breast cancer is the most common cancer among women worldwide, claiming the lives of hundreds of thousands of women each year. Near infrared diffuse optical tomography (DOT) has demonstrated a great potential as an adjunct modality for differentiation of malignant and benign breast lesions and for monitoring treatment response of patients with locally advanced breast cancers. The path toward commercialization of DOT techniques depends upon the improvement of robustness and user-friendliness of this technique in hardware and software. In the past, our group have developed three frequency domain prototype systems which were used in several clinical studies. In this study, we introduce our newly under development US-guided DOT system which is being improved in terms of size, robustness and user friendliness by several custom electronic and mechanical design. A new and robust probe designed to reduce preparation time in clinical process. The processing procedure, data selection and user interface software also updated. With all these improvements, our new system is more robust and accurate which is one step closer to commercialization and wide use of this technology in clinical settings. This system is aimed to be used by minimally trained user in the clinical settings with robust performance. The system performance has been tested in the phantom experiment and initial results are demonstrated in this study. We are currently working on finalizing this system and do further testing to validate the performance of this system. We are aiming toward use of this system in clinical setting for patients with breast cancer.

  18. Cervical gross tumor volume dose predicts local control using magnetic resonance imaging/diffusion-weighted imaging-guided high-dose-rate and positron emission tomography/computed tomography-guided intensity modulated radiation therapy.

    Science.gov (United States)

    Dyk, Pawel; Jiang, Naomi; Sun, Baozhou; DeWees, Todd A; Fowler, Kathryn J; Narra, Vamsi; Garcia-Ramirez, Jose L; Schwarz, Julie K; Grigsby, Perry W

    2014-11-15

    Magnetic resonance imaging/diffusion weighted-imaging (MRI/DWI)-guided high-dose-rate (HDR) brachytherapy and (18)F-fluorodeoxyglucose (FDG) - positron emission tomography/computed tomography (PET/CT)-guided intensity modulated radiation therapy (IMRT) for the definitive treatment of cervical cancer is a novel treatment technique. The purpose of this study was to report our analysis of dose-volume parameters predicting gross tumor volume (GTV) control. We analyzed the records of 134 patients with International Federation of Gynecology and Obstetrics stages IB1-IVB cervical cancer treated with combined MRI-guided HDR and IMRT from July 2009 to July 2011. IMRT was targeted to the metabolic tumor volume and lymph nodes by use of FDG-PET/CT simulation. The GTV for each HDR fraction was delineated by use of T2-weighted or apparent diffusion coefficient maps from diffusion-weighted sequences. The D100, D90, and Dmean delivered to the GTV from HDR and IMRT were summed to EQD2. One hundred twenty-five patients received all irradiation treatment as planned, and 9 did not complete treatment. All 134 patients are included in this analysis. Treatment failure in the cervix occurred in 24 patients (18.0%). Patients with cervix failures had a lower D100, D90, and Dmean than those who did not experience failure in the cervix. The respective doses to the GTV were 41, 58, and 136 Gy for failures compared with 67, 99, and 236 Gy for those who did not experience failure (PD100, D90, and Dmean doses required for ≥90% local control to be 69, 98, and 260 Gy (P<.001). Total dose delivered to the GTV from combined MRI-guided HDR and PET/CT-guided IMRT is highly correlated with local tumor control. The findings can be directly applied in the clinic for dose adaptation to maximize local control. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Systematic study of target localization for bioluminescence tomography guided radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Jingjing [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University, Baltimore, Maryland 21231 and School of Physics and Information Technology, Shaanxi Normal University, Shaanxi 710119 (China); Zhang, Bin; Reyes, Juvenal; Wong, John W.; Wang, Ken Kang-Hsin, E-mail: kwang27@jhmi.edu [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University, Baltimore, Maryland 21231 (United States); Iordachita, Iulian I. [Laboratory for Computational Sensing and Robotics, Johns Hopkins University, Baltimore, Maryland 21218 (United States); Lu, Zhihao [Department of Oncology and Department of Surgery, Johns Hopkins University, Baltimore, Maryland 21231 and Key laboratory of Carcinogenesis and Translational Research, Department of GI Oncology, Peking University, Beijing Cancer Hospital and Institute, Beijing 100142 (China); Brock, Malcolm V. [Department of Oncology and Department of Surgery, Johns Hopkins University, Baltimore, Maryland 21231 (United States); Patterson, Michael S. [Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario L8S 4L8 (Canada)

    2016-05-15

    Purpose: To overcome the limitation of CT/cone-beam CT (CBCT) in guiding radiation for soft tissue targets, the authors developed a spectrally resolved bioluminescence tomography (BLT) system for the small animal radiation research platform. The authors systematically assessed the performance of the BLT system in terms of target localization and the ability to resolve two neighboring sources in simulations, tissue-mimicking phantom, and in vivo environments. Methods: Multispectral measurements acquired in a single projection were used for the BLT reconstruction. The incomplete variables truncated conjugate gradient algorithm with an iterative permissible region shrinking strategy was employed as the optimization scheme to reconstruct source distributions. Simulation studies were conducted for single spherical sources with sizes from 0.5 to 3 mm radius at depth of 3–12 mm. The same configuration was also applied for the double source simulation with source separations varying from 3 to 9 mm. Experiments were performed in a standalone BLT/CBCT system. Two self-illuminated sources with 3 and 4.7 mm separations placed inside a tissue-mimicking phantom were chosen as the test cases. Live mice implanted with single-source at 6 and 9 mm depth, two sources at 3 and 5 mm separation at depth of 5 mm, or three sources in the abdomen were also used to illustrate the localization capability of the BLT system for multiple targets in vivo. Results: For simulation study, approximate 1 mm accuracy can be achieved at localizing center of mass (CoM) for single-source and grouped CoM for double source cases. For the case of 1.5 mm radius source, a common tumor size used in preclinical study, their simulation shows that for all the source separations considered, except for the 3 mm separation at 9 and 12 mm depth, the two neighboring sources can be resolved at depths from 3 to 12 mm. Phantom experiments illustrated that 2D bioluminescence imaging failed to distinguish two sources

  20. Development of a guidance guide for dosimetry in computed tomography; Desenvolvimento de um guia orientativo para dosimetria em tomografia computadorizada

    Energy Technology Data Exchange (ETDEWEB)

    Fontes, Ladyjane Pereira

    2016-07-01

    Due to frequent questions from users of ionization chambers pencil type calibrated in the Instrument Calibration Laboratory of the Institute of Energy and Nuclear Research (LCI - IPEN), on how to properly apply the factors indicated in their calibration certificates, a guide was prepared guidance for dosimetry in computed tomography. The guide includes guidance prior knowledge of half value layer (HVL), as it is necessary to know the effective beam energy for application quality for correction factor (kq). The evaluation of HVL in TC scanners becomes a difficult task due to system geometry and therefore a survey was conducted of existing methodologies for the determination of HVL in clinical beams Computed Tomography, taking into account technical, practical and economic factors. In this work it was decided to test a Tandem System consists of absorbing covers made in the workshop of IPEN, based on preliminary studies due to low cost and good response. The Tandem system consists of five cylindrical absorbing layers of 1mm, 3mm, 5mm, 7mm and 10mm aluminum and 3 cylindrical absorbing covers 15mm, 25mm and acrylic 35mm (PMMA) coupled to the ionization chamber of commercial pencil type widely used in quality control tests in dosimetry in clinical beams Computed tomography. Through Tandem curves it was possible to assess HVL values and from the standard curve pencil-type ionization chamber, Kq find the appropriate beam. The elaborate Guide provides information on how to build the calibration curve on the basis of CSR, to find the Kq and information for construction Tandem curve, to find values close to CSR. (author)

  1. C-arm cone beam computed tomography needle path overlay for fluoroscopic guided vertebroplasty.

    Science.gov (United States)

    Tam, Alda L; Mohamed, Ashraf; Pfister, Marcus; Chinndurai, Ponraj; Rohm, Esther; Hall, Andrew F; Wallace, Michael J

    2010-05-01

    Retrospective review. To report our early clinical experience using C-arm cone beam computed tomography (C-arm CBCT) with fluoroscopic overlay for needle guidance during vertebroplasty. C-arm CBCT is advanced three-dimensional (3-D) imaging technology that is currently available on state-of-the-art flat panel based angiography systems. The imaging information provided by C-arm CBCT allows for the acquisition and reconstruction of "CT-like" images in flat panel based angiography/interventional suites. As part of the evolution of this technology, enhancements allowing the overlay of cross-sectional imaging information can now be integrated with real time fluoroscopy. We report our early clinical experience with C-arm CBCT with fluoroscopic overlay for needle guidance during vertebroplasty. This is a retrospective review of 10 consecutive oncology patients who underwent vertebroplasty of 13 vertebral levels using C-arm CBCT with fluoroscopic overlay for needle guidance from November 2007 to December 2008. Procedural data including vertebral level, approach (transpedicular vs. extrapedicular), access (bilateral vs. unilateral) and complications were recorded. Technical success with the overlay technology was assessed based on accuracy which consisted of 4 measured parameters: distance from target to needle tip, distance from planned path to needle tip, distance from midline to needle tip, and distance from the anterior 1/3 of the vertebral body to needle tip. Success within each parameter required that the distance between the needle tip and parameter being evaluated be no more than 5 mm on multiplanar CBCT or fluoroscopy. Imaging data for 12 vertebral levels was available for review. All vertebral levels were treated using unilateral access and 9 levels were treated with an extrapedicular approach. Technical success rates were 92% for both distance from planned path and distance from midline to final needle tip, 100% when distance from needle tip to the anterior 1

  2. Using Microcomputers for Institutional Research.

    Science.gov (United States)

    Suttle, J. Lloyd

    1984-01-01

    Many institutional researchers will find that the microcomputer leads to greater efficiency in everything that they do, especially in the two most critical elements of their jobs: thinking and communicating. (Author/MLW)

  3. Evaluation of periodontal tissue during orthodontic tooth movement in rats: a micro-computed tomography study%牙齿移动过程中牙槽骨显微结构动态变化的微型CT研究

    Institute of Scientific and Technical Information of China (English)

    茹楠; 庄丽; 白玉兴

    2011-01-01

    Objective To observe the microstructure changes of rat alveolar bone around tooth root under orthodontic force loading. Methods Ten 10-week-old rats were included in the study. Upper first molars were moved mesially with 0.196 N of force. The alveolar bone around the root of upper first molar was scanned by a micro-computed tomography scan system(SkyScan-1076) in different period after the initiation of orthodontic force loading( on the 3rd, 7th, 14th day after force loading ) and analyzed by a speciallydesigned software to measure the microstructure parameters of alveolar bone ( bone volume fraction, bone surface to volume ratio, structure model index, trabecular thickness, trabecular separation, trabecular number). Results From the 7th day, bone volume fraction[(41±14)%], structure model index( 1.51 ±0. 52) and trabecular separation [(90 ± 30 ) μm] changed significantly in the compressive area compared with those[(64±15)%, (0.51 ±0.85), (56 ±-10) μm] on the 3rd day. From the 14th day, bone volume fraction[(78 ± 14)%], structure model index(0. 28 ± 0. 20) and trabecular separation[(29 ±13) μm] changed significantly in the tension area compared with those[(67 ± 14)%, (0.40 ±0.41 ),(48 ± 15) μm] on the 7th day. No difference on trabecular number was found between the compressive area and tension area(P >0. 05). Conclusions The significant resorption of the alveolar bone was observed on the 7th days in the compressive area and the deposition of the alveolar bone was observed on the 14th day in the compressive area after orthodontic force loading.%目的 通过微型CT探讨正畸牙齿移动过程中矫治力对牙槽骨骨小梁的影响规律,以期为正畸临床提供参考.方法 选择10周龄SD雄性大鼠10只建立实验动物模型,施加0.196 N矫治力,近中移动上颌第一磨牙,分别于加力前、加力后第3、7、14 d对大鼠上颌牙槽骨骨小梁进行微型CT扫描,计算骨体积分数、骨表面积体积比、结构模

  4. Cerebral air embolism as a complication of computed tomography-guided marking of the lung: depiction of air inflow route from a pulmonary vein to the left atrium.

    Science.gov (United States)

    Higashino, Takanori; Noma, Satoshi; Nishimoto, Yuko; Endo, Junki; Taguchi, Yoshio; Shindo, Toru

    2011-02-01

    Air embolism in the arterial system is a very rare but potentially fatal complication of percutaneous transthoracic needle biopsy or marking. We report a case of a patient with interstitial pneumonia associated with Sjögren syndrome, who presented with systemic arterial air embolism as a complication of computed tomography-guided marking of the lung. The air inflow route was depicted clearly on computed tomography from the peripheral pulmonary vein that crossed the needle pathway to the left atrium.

  5. Tevatron extraction microcomputer

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, L.; Finley, D.A.; Harrison, M.; Merz, W.

    1985-06-01

    Extraction in the Fermilab Tevatron is controlled by a multi-processor Multibus microcomputer system called QXR (Quad eXtraction Regulator). QXR monitors several analog beam signals and controls three sets of power supplies: the ''bucker'' and ''pulse'' magnets at a rate of 5760 Hz, and the ''QXR'' magnets at 720 Hz. QXR supports multiple slow spills (up to a total of 35 seconds) with multiple fast pulses intermixed. It linearizes the slow spill and bucks out the high frequency components. Fast extraction is done by outputting a variable pulse waveform. Closed loop learning techniques are used to improve performance from cycle to cycle for both slow and fast extraction. The system is connected to the Tevatron clock system so that it can track the machine cycle. QXR is also connected to the rest of the Fermilab control system, ACNET. Through ACNET, human operators and central computers can monitor and control extraction through communications with QXR. The controls hardware and software both employ some standard and some specialized components. This paper gives an overview of QXR as a control system; another paper summarizes performance.

  6. Effective Microcomputer Management: An Executive Level Guide.

    Science.gov (United States)

    1986-03-27

    capacity of what can be accomplished - but at a price. Brod [Ref. 25: pp. 16-171 uses the term " technostress " to describe the inability to cope with...T., Structured Analysis and System Sr~cifcatonYourdon, Inc. , 1S/9. 25. Brod, C. , Technostress , Addison-Wesley, 1984. 26. Brod, C. Technostress

  7. Percutaneous transthoracic computed tomography-guided AICD insertion in a patient with extracardiac Fontan conduit.

    LENUS (Irish Health Repository)

    Murphy, Darra T

    2011-02-01

    Percutaneous pulmonary venous atrial puncture was performed under computed tomography guidance to successfully place an automated implantable cardiac defibrillator into a 26-year-old patient with extracardiac Fontan conduit who had presented with two out-of-hospital cardiac arrests. The procedure avoided the need for lead placement at thoracotomy.

  8. Computed tomography-guided interstitial high dose rate brachytherapy for centrally located liver tumours: a single institution study

    Energy Technology Data Exchange (ETDEWEB)

    Tselis, Nikolaos; Chatzikonstantinou, Georgios; Zamboglou, Nikolaos [Klinikum Offenbach, Department of Radiation Oncology, Offenbach am Main (Germany); Kolotas, Christos [Hirslanden Medical Center, Institute for Radiotherapy, Aarau (Switzerland); Milickovic, Natasa; Baltas, Dimos [Klinikum Offenbach, Department of Medical Physics and Engineering, Offenbach am Main (Germany)

    2013-08-15

    To evaluate the clinical outcome of computed tomography (CT)-guided interstitial (IRT) high-dose-rate (HDR) brachytherapy (BRT) in the treatment of unresectable primary and secondary liver malignancies. This report updates and expands our previously described experience with this treatment technique. Forty-one patients with 50 tumours adjacent to the liver hilum and bile duct bifurcation were treated in 59 interventions of CT-guided IRT HDR BRT. The tumours were larger than 4 cm with a median volume of 84 cm{sup 3} (38-1,348 cm{sup 3}). The IRT HDR BRT delivered a median total physical dose of 20.0 Gy (7.0-32.0 Gy) in twice daily fractions of median 7.0 Gy (4.0-10.0 Gy) in 19 patients and in once daily fractions of median 8.0 Gy (7.0-14.0 Gy) in 22 patients. With a median follow-up of 12.4 months, the local control for metastatic hepatic tumours was 89 %, 73 % and 63 % at 6, 12 and 18 months respectively. The local control for primary hepatic tumours was 90 %, 81 % and 50 % at 6, 12 and 18 months respectively. Severe side effects occurred in 5.0 % of interventions with no treatment-related deaths. CT-guided IRT HDR BRT is a promising procedure for the radiation treatment of centrally located liver malignancies. (orig.)

  9. 3D artificial bones for bone repair prepared by computed tomography-guided fused deposition modeling for bone repair.

    Science.gov (United States)

    Xu, Ning; Ye, Xiaojian; Wei, Daixu; Zhong, Jian; Chen, Yuyun; Xu, Guohua; He, Dannong

    2014-09-10

    The medical community has expressed significant interest in the development of new types of artificial bones that mimic natural bones. In this study, computed tomography (CT)-guided fused deposition modeling (FDM) was employed to fabricate polycaprolactone (PCL)/hydroxyapatite (HA) and PCL 3D artificial bones to mimic natural goat femurs. The in vitro mechanical properties, in vitro cell biocompatibility, and in vivo performance of the artificial bones in a long load-bearing goat femur bone segmental defect model were studied. All of the results indicate that CT-guided FDM is a simple, convenient, relatively low-cost method that is suitable for fabricating natural bonelike artificial bones. Moreover, PCL/HA 3D artificial bones prepared by CT-guided FDM have more close mechanics to natural bone, good in vitro cell biocompatibility, biodegradation ability, and appropriate in vivo new bone formation ability. Therefore, PCL/HA 3D artificial bones could be potentially be of use in the treatment of patients with clinical bone defects.

  10. Percutaneous computed tomography-guided core needle biopsy of soft tissue tumors: results and correlation with surgical specimen analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chojniak, Rubens; Grigio, Henrique Ramos; Bitencourt, Almir Galvao Vieira; Pinto, Paula Nicole Vieira; Tyng, Chiang J.; Cunha, Isabela Werneck da; Aguiar Junior, Samuel; Lopes, Ademar, E-mail: chojniak@uol.com.br [Hospital A.C. Camargo, Sao Paulo, SP (Brazil)

    2012-09-15

    Objective: To evaluate the efficacy of percutaneous computed tomography (CT)-guided core needle biopsy of soft tissue tumors in obtaining appropriate samples for histological analysis, and compare its diagnosis with the results of the surgical pathology as available. Materials and Methods: The authors reviewed medical records, imaging and histological reports of 262 patients with soft-tissue tumors submitted to CT-guided core needle biopsy in an oncologic reference center between 2003 and 2009. Results: Appropriate samples were obtained in 215 (82.1%) out of the 262 patients. The most prevalent tumors were sarcomas (38.6%), metastatic carcinomas (28.8%), benign mesenchymal tumors (20.5%) and lymphomas (9.3%). Histological grading was feasible in 92.8% of sarcoma patients, with the majority of them (77.9%) being classified as high grade tumors. Out of the total sample, 116 patients (44.3%) underwent surgical excision and diagnosis confirmation. Core biopsy demonstrated 94.6% accuracy in the identification of sarcomas, with 96.4% sensitivity and 89.5% specificity. A significant intermethod agreement about histological grading was observed between core biopsy and surgical resection (p < 0.001; kappa = 0.75). Conclusion: CT-guided core needle biopsy demonstrated a high diagnostic accuracy in the evaluation of soft tissue tumors as well as in the histological grading of sarcomas, allowing an appropriate therapeutic planning (author)

  11. Study of computed tomography-guided fine needle aspiration cytology of thoracic lesions

    Directory of Open Access Journals (Sweden)

    Maggad Rangaswamy

    2012-01-01

    Conclusion: CT-guided TFNAC is a low cost, safe, minimally invasive and accurate diagnostic procedure with high sensitivity and specificity and when interpreted in conjunction with clinical and radiological data can prevent some of the pitfalls in diagnosis.

  12. Clinical efficacy of computed tomography-guided iodine-125 seed implantation therapy in patients with advanced spinal metastatic tumors

    Directory of Open Access Journals (Sweden)

    Zhang LY

    2015-12-01

    Full Text Available Liyun Zhang,1,2,* Jian Lu,2,* Zhongmin Wang,3 Yingsheng Cheng,4 Gaojun Teng,5 Kemin Chen4 1Medical College of Soochow University, Suzhou, 2Department of Radiology, Shanghai Ruijin Hospital Luwan Branch, 3Department of Radiology, Shanghai Ruijin Hospital, 4Department of Radiology, Shanghai the Sixth People Hospital, Shanghai, 5Department of Radiology, Jiangsu Key Laboratory of Molecular and Functional Imaging, Zhongda Hospital, Medical School, Southeast University, Nanjing, People’s Republic of China *These authors contributed equally to this work Objective: The purpose of this study was to examine the safety and clinical efficacy of computed tomography (CT-guided radioactive iodine-125 (125I seed implantation treatment in patients with spinal metastatic tumors.Methods: We retrospectively analyzed 20 cases of spinal metastatic tumors, including nine men and eleven women aged 50–79 years (mean age: 61.1 years. We used treatment planning system (TPS to construct three-dimensional images of the spinal metastatic tumors and to determine what number and dose rate distribution to use for the 125I seeds. The matched peripheral dose of the 125I seed implantation was 90–130 Gy. Twenty-four spinal metastatic tumors were treated by CT-guided radioactive 125I seed implantation. A median of 19 (range: 4–43 125I seeds were implanted.Results: Twenty cases were followed for a median of 15.3 months (range: 7–32 months. The rate of pain relief was 95%. The median control time for all of the patients was 12.5 months. The 3-, 6-, and 12-month cumulative local control rates were 100%, 95%, and 60%, respectively. The median survival time for all of the patients was 16 months. The cumulative 6- and 12-month survival rates were 100% and 78.81%, respectively. No major complications were observed. No 125I seeds were lost or migrated to other tissues or organs.Conclusion: CT-guided radioactive 125I seed implantation is a safe, effective, and minimally

  13. Magnetic resonance imaging-guided attenuation and scatter corrections in three-dimensional brain positron emission tomography

    CERN Document Server

    Zaidi, H; Slosman, D O

    2003-01-01

    Reliable attenuation correction represents an essential component of the long chain of modules required for the reconstruction of artifact-free, quantitative brain positron emission tomography (PET) images. In this work we demonstrate the proof of principle of segmented magnetic resonance imaging (MRI)-guided attenuation and scatter corrections in 3D brain PET. We have developed a method for attenuation correction based on registered T1-weighted MRI, eliminating the need of an additional transmission (TX) scan. The MR images were realigned to preliminary reconstructions of PET data using an automatic algorithm and then segmented by means of a fuzzy clustering technique which identifies tissues of significantly different density and composition. The voxels belonging to different regions were classified into air, skull, brain tissue and nasal sinuses. These voxels were then assigned theoretical tissue-dependent attenuation coefficients as reported in the ICRU 44 report followed by Gaussian smoothing and additio...

  14. A 2-step optical coherence tomography guided therapeutic approach to acute myocardial infarction secondary to stent thrombosis

    Energy Technology Data Exchange (ETDEWEB)

    Bogale, Nigussie, E-mail: nigussie.bogale@lyse.net [Vancouver General Hospital, Division of Cardiology University of British Columbia, Vancouver, BC (Canada); Stavanger University Hospital, Department of Cardiology, Stavanger (Norway); Lempereur, Mathieu; Fung, Anthony Y. [Vancouver General Hospital, Division of Cardiology University of British Columbia, Vancouver, BC (Canada)

    2016-07-15

    Myocardial infarction secondary to stent thrombosis has high mortality and recurrence rate. Emergency PCI has high risk of no-reflow. We used a 2-step approach of early recanalization with minimal mechanical intervention followed by delayed PCI 1–2 days later guided by Optical Coherence Tomography (OCT). From October 2011 to December 2013, we treated 5 patients with this approach. Time from early recanalization to the delayed definitive PCI was 1 day (median, range 1–3 days). All the OCT images were diagnostic with a clear view of the underlying structures. Summary: A 2-step approach to treat stent thrombosis appears beneficial with low incidence of peri-procedural thrombosis or no-reflow phenomena during the second step, and superb OCT imaging.

  15. Optical Coherence Tomography Guided Percutaneous Coronary Intervention With Nobori Stent Implantation in Patients With Non-ST-Segment-Elevation Myocardial Infarction (OCTACS) Trial

    DEFF Research Database (Denmark)

    Antonsen, Lisbeth; Thayssen, Per; Maehara, Akiko

    2015-01-01

    BACKGROUND: Incomplete strut coverage has been documented an important histopathologic morphometric predictor for later thrombotic events. This study sought to investigate whether optical coherence tomography (OCT)-guided percutaneous coronary intervention with Nobori biolimus-eluting stent impla...... at 6-month follow-up in comparison with angiographic guidance alone. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02272283....

  16. Osteogenesis effect of guided bone regeneration combined with alveolar cleft grafting: assessment by cone beam computed tomography.

    Science.gov (United States)

    Xiao, W-L; Zhang, D-Z; Chen, X-J; Yuan, C; Xue, L-F

    2016-06-01

    Cone beam computed tomography (CBCT) allows for a significantly lower radiation dose than conventional computed tomography (CT) scans and provides accurate images of the alveolar cleft area. The osteogenic effect of guided bone regeneration (GBR) vs. conventional alveolar bone grafting alone for alveolar cleft defects was evaluated in this study. Sixty alveolar cleft patients were divided randomly into two groups. One group underwent GBR using acellular dermal matrix film combined with alveolar bone grafting using iliac crest bone grafts (GBR group), while the other group underwent alveolar bone grafting only (non-GBR group). CBCT images were obtained at 1 week and at 3 months following the procedure. Using Simplant 11.04 software, the bone resorption rate was calculated and compared between the two groups. The bone resorption rate from 1 week to 3 months following bone grafting without the GBR technique was 36.50±5.04%, whereas the bone resorption rate using the GBR technique was 31.69±5.50% (P=0.017). The application of autogenous iliac bone combined with the GBR technique for alveolar bone grafting of alveolar cleft patients can reduce bone resorption and result in better osteogenesis.

  17. Computed tomography-guided bupivacaine and corticosteroid injection for the treatment of symptomatic calcification in the great toe tendon

    Directory of Open Access Journals (Sweden)

    Karatoprak O

    2014-04-01

    Full Text Available Omer Karatoprak,1 Sinan Karaca,2 Mehmet Nuri Erdem,3 Ozgur Karaman,2 Azmi Hamzaoglu41Department of Orthopedic Surgery, Kadikoy Florence Nightingale Hospital, Istanbul, Turkey; 2Department of Orthopedic Surgery, Fatih Sultan Mehmet Training and Research Hospital Atasehir, Istanbul, Turkey; 3Department of Orthopedics and Traumatology, Kolan International Hospital Sisli, Istanbul, Turkey; 4Department of Orthopedic Surgery, Istanbul Florence Nightingale Hospital, Istanbul TurkeyBackground: Calcification in the great toe tendon is a rare disorder that is characterized by the deposition of calcium on degenerative collagen fibrils.Case presentations: In this report, we present two cases of calcific tendonitis: one in the adductor hallucis and the other in the flexor hallucis longus tendon. We preferred computed tomography-guided steroid injection in our cases because of pain unresponsive to conservative treatment. Patients were free of symptoms at the follow-up visit, 4 weeks after injection.Conclusion: Calcification of the hallux tendons is a rare disorder. Treatment of tendonitis consists of nonsteroidal anti-inflammatory drugs. Local anesthetic and steroid injection may be considered in cases unresponsive to conservative treatment. Because of the anatomic location of tendons, injection could be difficult. Computed tomography guidance may improve the success rate of injections.Keywords: bupivacaine, calcification, great toe tendons, corticosteroid injection

  18. Computed tomography-guided percutaneous biopsy of pancreatic masses using pneumodissection; Biopsia percutanea de massas pancreaticas guiada por tomografia computadorizada com pneumodisseccao

    Energy Technology Data Exchange (ETDEWEB)

    Tyng, Chiang Jeng; Bitencourt, Almir Galvao Vieira; Almeida, Maria Fernanda Arruda; Barbosa, Paula Nicole Vieira; Martins, Eduardo Bruno Lobato; Junior, Joao Paulo Kawaoka Matushita; Chojniak, Rubens, E-mail: chiangjengtyng@gmail.com [Hospital A.C. Camargo, Sao Paulo, SP (Brazil). Dept. de Imagem; Coimbra, Felipe Jose Fernandez [Hospital A.C. Camargo, Sao Paulo, SP (Brazil). Dept. de Cirurgia Abdominal

    2013-05-15

    Objective: to describe the technique of computed tomography-guided percutaneous biopsy of pancreatic tumors with pneumodissection. Materials and methods: in the period from June 2011 to May 2012, seven computed tomography guided percutaneous biopsies of pancreatic tumors utilizing pneumodissection were performed in the authors' institution. All the procedures were performed with an automatic biopsy gun and coaxial system with Tru-core needles. The biopsy specimens were histologically assessed. Results: in all the cases the pancreatic mass could not be directly approached by computed tomography without passing through major organs and structures. The injection of air allowed the displacement of adjacent structures and creation of a safe coaxial needle pathway toward the lesion. Biopsy was successfully performed in all the cases, yielding appropriate specimens for pathological analysis. Conclusion: Pneumodissection is a safe, inexpensive and technically easy approach to perform percutaneous biopsy in selected cases where direct access to the pancreatic tumor is not feasible. (author)

  19. Cone-Beam Computed Tomography for Image-Guided Radiation Therapy of Prostate Cancer

    Science.gov (United States)

    2010-01-01

    extrafo al spot of an x-ray tube in one-beam omputed tomography, AAPM , Houston, TX,2008. 13 5. E. Pearson, S. Cho, X. Pan, and C. A. Pelizzari, Dose...redu tion in CBCT via intensity-weighted region-of-interest imaging, AAPM , Houston, TX, 2008.6. E. Pearson, S. Cho, X. Pan, and C. A. Pelizzari...Pelizzari, and X. Pan, Exa t image re onstru tion in reverseheli al one-beam CT for radiation therapy, AAPM , Minneapolis, MN, 2007.9. X. Han, S. Cho

  20. Can the need for colectomy after computed tomography-guided percutaneous drainage for diverticular abscess be predicted?

    Science.gov (United States)

    Felder, Seth I; Barmparas, Galinos; Lynn, Juliane; Murrell, Zuri; Margulies, Daniel R; Fleshner, Phillip

    2013-10-01

    The primary aim of this study was to define predictors of computed tomography (CT)-guided percutaneous abscess drainage treatment failure in complicated diverticulitis. A 10-year retrospective analysis of inpatients seen in surgical consultation for diverticular abscess management subsequently referred for CT-guided percutaneous drainage (PD) was conducted. The clinical courses of patients undergoing a technically successful PD were categorized into three groups: 1) no colectomy; 2) elective colectomy; and 3) nonelective colectomy. Forty study patients were identified. Thirteen (33%) of the 40 patients required a nonelective colectomy, 20 patients (50%) underwent elective resection, and seven patients (18%) have been managed nonoperatively with no recurrent diverticulitis for a median of 46.8 months (range, 3.2 to 84.3 months). Forward logistic regression identified the presence of immunosuppression or renal insufficiency (creatinine 1.5 mg/dL or greater) as factors independently associated with failure of PD and need for nonelective colectomy. No clinical, laboratory, or radiologic variables were predictive of long-term nonoperative success. Although PD allows for the resolution of intra-abdominal sepsis for most cases of diverticulitis complicated by an abscess, a substantial proportion progress to nonelective colectomy, emphasizing the need for clinical vigilance in follow-up.

  1. Computed tomography-guided interstitial HDR brachytherapy (CT-HDRBT) of the liver in patients with irresectable intrahepatic cholangiocarcinoma.

    Science.gov (United States)

    Schnapauff, Dirk; Denecke, Timm; Grieser, Christian; Collettini, Federico; Colletini, Federico; Seehofer, Daniel; Sinn, Marianne; Banzer, Jan; Lopez-Hänninen, Enrique; Hamm, Bernd; Wust, Peter; Gebauer, Bernhard

    2012-06-01

    This study was designed to investigate the clinical outcome of patients with irresectable, intrahepatic cholangiocarcinoma (IHC) treated with computed tomography (CT)-guided HDR-brachytherapy (CT-HDRBT) for local tumor ablation. Fifteen consecutive patients with histologically proven cholangiocarcinoma were selected for this retrospective study. Patients were treated by high-dose-rate internal brachytherapy (HDRBT) using an Iridium-192 source in afterloading technique through CT-guided percutaneous placed catheters. A total of 27 brachytherapy treatments were performed in these patients between 2006 and 2009. Median tumor enclosing target dose was 20 Gy, and mean target volume of the radiated tumors was 131 (±90) ml (range, 10-257 ml). Follow-up consisted of clinical visits and magnetic resonance imaging of the liver every third month. Statistical evaluation included survival analysis using the Kaplan-Meier method. After a median follow-up of 18 (range, 1-27) months after local ablation, 6 of the 15 patients are still alive; 4 of them did not get further chemotherapy and are regarded as disease-free. The reached median local tumor control was 10 months; median local tumor control, including repetitive local ablation, was 11 months. Median survival after local ablation was 14 months and after primary diagnosis 21 months. In view of current clinical data on the clinical outcome of cholangiocarcinoma, locally ablative treatment with CT-HDRBT represents a promising and safe technique for patients who are not eligible for tumor resection.

  2. Computed tomography- and fluoroscopy-guided percutaneous screw fixation of low-grade isthmic spondylolisthesis in adults: a new technique

    Energy Technology Data Exchange (ETDEWEB)

    Amoretti, Nicolas; Huwart, Laurent; Browaeys, Patrick; Nouri, Yasir; Ibba, Caroline [Hopital Archet 2, Centre Hospitalo-Universitaire de Nice, Department of Radiology, Nice (France); Hauger, Olivier [Hopital Pellegrin, Centre Hospitalo-Universitaire de Bordeaux, Department of Radiology, Bordeaux (France); Marcy, Pierre-Yves [Antoine Lacassagne Cancer Research Institute, Department of Radiology, Nice (France); Boileau, Pascal [Hopital Archet 2, Centre Hospitalo-Universitaire de Nice, Department of Orthopedic Surgery, Nice (France)

    2012-12-15

    To evaluate the feasibility of computed tomography (CT)- and fluoroscopy-guided percutaneous screw fixation for the treatment of low-grade isthmic spondylolisthesis in adults. Ten consecutive adult patients (four men and six women; mean age: 57.1 [range, 44-78 years]) were prospectively treated by percutaneous screw fixation for low-grade (six grade 1 and four grade 2) isthmic spondylolisthesis of L5. For each patient, two 4.0-mm Asnis III cannulated screws were placed to fix the pars interarticularis defects. All procedures were performed under local anaesthesia by using CT and fluoroscopy guidance. Post-operative outcome was assessed using the visual analogue scale and Oswestry Disability Index (ODI) scores. The procedure time ranged from 45 to 60 min. The mean screw length was 27 mm (range, 24-32 mm). The VAS and ODI measurements {+-} SD decreased from 7.8 {+-} 0.9 preoperatively to 1.5 {+-} 1.1 at the last 2-year follow-up, and from 62.3 {+-} 17.2 to 15.1 {+-} 6.0, respectively (P < 0.001 in both cases). Neither slip progression nor screw failure was noted. This feasibility study showed that CT- and fluoroscopy-guided percutaneous screw fixation could be a rapid, safe and effective method of treating low-grade isthmic spondylolisthesis. (orig.)

  3. Fluorescence-Guided Probes of Aptamer-Targeted Gold Nanoparticles with Computed Tomography Imaging Accesses for in Vivo Tumor Resection

    Science.gov (United States)

    Li, Cheng-Hung; Kuo, Tsung-Rong; Su, Hsin-Jan; Lai, Wei-Yun; Yang, Pan-Chyr; Chen, Jinn-Shiun; Wang, Di-Yan; Wu, Yi-Chun; Chen, Chia-Chun

    2015-01-01

    Recent development of molecular imaging probes for fluorescence-guided surgery has shown great progresses for determining tumor margin to execute the tissue resection. Here we synthesize the fluorescent gold nanoparticles conjugated with diatrizoic acid and nucleolin-targeted AS1411 aptamer. The nanoparticle conjugates exhibit high water-solubility, good biocompatibility, visible fluorescence and strong X-ray attenuation for computed tomography (CT) contrast enhancement. The fluorescent nanoparticle conjugates are applied as a molecular contrast agent to reveal the tumor location in CL1-5 tumor-bearing mice by CT imaging. Furthermore, the orange-red fluorescence emitting from the conjugates in the CL1-5 tumor can be easily visualized by the naked eyes. After the resection, the IVIS measurements show that the fluorescence signal of the nanoparticle conjugates in the tumor is greatly enhanced in comparison to that in the controlled experiment. Our work has shown potential application of functionalized nanoparticles as a dual-function imaging agent in clinical fluorescence-guided surgery. PMID:26507179

  4. Effectiveness of Computed Tomography Guided Percutaneous Radiofrequency Ablation Therapy for Osteoid Osteoma: Initial Results and Review of the Literature

    Science.gov (United States)

    Karagöz, Erdal; Özel, Deniz; Özkan, Fuat; Özel, Betül Duran; Özer, Özgur; Coşkun, Zafer Ünsal

    2016-01-01

    Summary Background The aim of this retrospective study is to determine our experience of technique success rate, complications and clinical results in long term follow up for computed tomography (CT)-guided radiofrequency ablation [RA] therapy for osteoid osteoma (OO). Material/Methods We performed RA therapy to 18 patients with OO referred to interventional radiology from other clinics primarily from orthopedics; between January 2011 to May 2014. Daytime and nighttime pain intensity of 18 patients was noted according to visual analog scale (VAS). After procedure pain intensity was compared with before one. We also discussed other factors can affect it. Results All procedures were completed technically successful for all patients [100%]. We did not experience any major complication or mortality. However we had 3 minor complications. Pain came back in 1 patient after 5 months from procedure and it was considered as recurrence. Dramatic pain intensity fall was seen in patients after procedure, both daytime and nighttime. However we did not find and statistically significant change in comparison of pain intensity reduce and time needed to return back to routine life when using patients demographic data and lesion size. Conclusions CT guided RA therapy of OO is minimally invasive, effective and secure procedure. PMID:27429671

  5. Software design methodologies for microcomputers

    Science.gov (United States)

    Dowsing, R. D.

    1982-05-01

    It is the development phase of the software lifecycle which has attracted a great deal of interest in the last few years. This paper surveys the stages in software production and the need for a rigorous, formal approach. This type of approach is illustrated by the development of a program for a microcomputer using structured programming techniques.

  6. History Microcomputer Games: Update 2.

    Science.gov (United States)

    Sargent, James E.

    1985-01-01

    Provides full narrative reviews of B-1 Nuclear Bomber (Avalon, 1982); American History Adventure (Social Science Microcomputer Review Software, 1985); Government Simulations (Prentice-Hall, 1985); and The Great War, FDR and the New Deal, and Hitler's War, all from New Worlds Software, 1985. Lists additional information on five other history and…

  7. Microcomputers and the Department Image.

    Science.gov (United States)

    Donaghy, William C.; Donaghy, Carole D.

    Ways in which various uses or applications of a microcomputer can help improve the image of a college or university department are discussed in this paper. The paper discusses applications such as instruction, word processing, management, programing, communications, statistics, and graphics, and audiences for these applications, such as department…

  8. Computed tomography-guided high-dose-rate brachytherapy in hepatocellular carcinoma: safety, efficacy, and effect on survival.

    Science.gov (United States)

    Mohnike, Konrad; Wieners, Gero; Schwartz, Franziska; Seidensticker, Max; Pech, Maciej; Ruehl, Ricarda; Wust, Peter; Lopez-Hänninen, Enrique; Gademann, Günther; Peters, Nils; Berg, Thomas; Malfertheiner, Peter; Ricke, Jens

    2010-09-01

    To determine the safety and efficacy of computed tomography (CT)-guided brachytherapy in hepatocellular carcinoma (HCC). A total of 83 patients were recruited, presenting with 140 HCC- lesions. Treatment was performed by CT-guided high-dose-rate (HDR) brachytherapy with an iridium-192 source. The primary endpoint was time to progression; secondary endpoints included local tumor control and overall survival (OS). A matched-pair analysis with patients not receiving brachytherapy was performed. Match criteria included the Cancer of the Liver Italian Program (CLIP) score, alpha-fetoprotein, presence, and extent of multifocal disease. For statistical analysis, Kaplan-Meier and Cox regression were performed. Mean and median cumulative TTP for all patients (n = 75) were 17.7 and 10.4 months. Five local recurrences were observed. The OS after inclusion reached median times of 19.4 months (all patients), 46.3 months (CLIP score, 0), 20.6 months (CLIP score, 1) 12.7 months, (CLIP score, 2), and 8.3 months (CLIP score, >or=3). The 1- and 3-year OS were 94% and 65% (CLIP score, 0), 69% and 12% (CLIP score, 1), and 48% and 19% (CLIP score, 2), respectively. Nine complications requiring intervention were encountered in 124 interventions. Matched-pair analysis revealed a significantly longer OS for patients undergoing CT-guided brachytherapy. Based on our results the study treatment could be safely performed. The study treatment had a beneficial effect on OS in patients with advanced HCC, with respect to (and depending on) the CLIP score and compared with OS in a historical control group. A high rate of local control was also observed, regardless of applied dose in a range of 15 to 25 Gy. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  9. Transpulmonary computed tomography-guided radiofrequency ablation of liver neoplasms abutting the diaphragm with multiple bipolar electrodes

    Directory of Open Access Journals (Sweden)

    Q Zhang

    2015-01-01

    Full Text Available Background: Neoplasm abutting the diaphragm is one kind of the special sites of liver neoplasms treated with radiofrequency ablation (RFA, the purpose of this study is to evaluate the feasibility and safety of computed tomography (CT-guided RFA of liver neoplasms abutting the diaphragm with multiple bipolar electrodes sequentially passing through the lung parenchyma. Materials and Methods: 37 patients were treated with transpulmonary CT-guided RFA. Technical success rate, perioperative complications, and local tumor progression were investigated. Results: The number of electrode (s sequentially passing through the lung parenchyma (NPLP was 1 electrode in 20 patients, 2 electrodes in 14 cases, and 3 electrodes in 3 cases. Technical success rate was 100%. The most of the perioperative complications were self-limiting and mainly included pneumothorax (11 cases, 2 needed percutaneous drainage, hemorrhage of the electrode track in the lung parenchyma (6 cases, a small amount of hemoperitoneum in perihepatic space (8 cases and discomfort of the right shoulder (7 cases. Local tumor progression occurred in 6 cases during the follow-up (3–12 months. Multivariate logistic regression analysis showed that the incidence of pneumothorax was not related to NPLP (P = 0.50, length of the electrode (s in the lung parenchyma (P = 0.18, types of anesthesia (P = 0.10, and indwelling time of the electrode (s in the lung parenchyma (P = 0.28. Conclusion: CT-guided RFA of liver neoplasms abutting the diaphragm with multiple bipolar electrodes sequentially passing through the lung parenchyma is a feasible and safe therapeutic option.

  10. Atmospheric tomography for artificial satellite observations with a single guide star.

    Science.gov (United States)

    Hart, Michael; Jefferies, Stuart M; Hope, Douglas A

    2016-08-15

    Estimation of wavefront errors in three dimensions is required to mitigate isoplanatic errors when using adaptive optics or numerical restoration algorithms to recover high-resolution images from blurred data taken through atmospheric turbulence. Present techniques rely on multiple beacons, either natural stars or laser guide stars, to probe the atmospheric aberration along different lines of sight, followed by tomographic projection of the measurements. In this Letter, we show that a three-dimensional estimate of the wavefront aberration can be recovered from measurements by a single guide star in the case where the aberration is stratified, provided that the telescope tracks across the sky with nonuniform angular velocity. This is generally the case for observations of artificial Earth-orbiting satellites, and the new method is likely to find application in ground-based telescopes used for space situational awareness.

  11. Computed tomography-guided endoscopic needle knife therapy for ileal pouch sinus.

    Science.gov (United States)

    Nyabanga, Custon T; Veniero, Joseph; Shen, Bo

    2016-11-01

    Ileal pouch-anal anastomosis surgery can be complicated by anastomotic leaks, leading to the formation of abscess and chronic sinus that have been routinely managed by a surgical approach. We developed the endoscopic needle knife sinusotomy (NKSi) technique, which has become a valid alternative. The basic principle of endoscopic NKSi is dissection and drainage of the sinus through its orifice internally into the lumen of pouch body. The success of NKSi requires an access to the sinus from the pouch side. One of the most challenging situations for NKSi is a closed orifice of the sinus, which leaves an isolated chronic abscess cavity. Here we report a case of complicated presacral sinus with a closed orifice that was not amenable to NKSi, necessitating a CT-guided guide wire placement and subsequent NKSi.

  12. Diagnostic yield and morbidity by neuronavigation-guided frameless stereotactic biopsy using magnetic resonance imaging and by frame-based computed tomography-guided stereotactic biopsy

    Directory of Open Access Journals (Sweden)

    Masamitsu Nishihara

    2014-01-01

    Full Text Available Background: We compared the diagnostic yield and morbidity by frame-based computed tomography-guided stereotactic biopsy (CTSTB with Brown-Roberts-Wells (BRW unit and by neuronavigation-guided frameless stereotactic biopsy (NSTB using magnetic resonance imaging (MRI. Methods: The subjects′ age range was 15-83 years. CTSTB with BRW unit was performed for 59 tumors (58 cases, 1988-2007. NSTB was performed for 38 tumors (35 cases, 2007-2013 with the needle sheath attached to the head holder. By NSTB, target locations of sampling points and trajectories were confirmed by using MRI. Diffusion tensor imaging-based fiber tractography was used to achieve safe trajectories. STB by using BRW did not visualize the trajectory virtually; however, the planning images for NSTB were able to show the trajectory virtually before the procedure. Results: Histological diagnoses were established for 93 tumors at the first biopsy. The diagnostic yield was 94.9% by CTSTB and 97.4% by NSTB (P = 0.944. The morbidity rate was 5.1% by CTSTB and 0% by NSTB (P = 0.417. The absolute risk reduction was 23.1% by NSTB when the targets were basal ganglia (putamen, globus pallidus or thalamus. In the cases of glioma for which the targets were basal ganglia (putamen, globus pallidus or thalamus, the absolute risk reduction by NSTB was 30%. Conclusions: There was no significant difference between CTSTB and NSTB concerning the diagnostic yield and morbidity. However, when the target is the basal ganglia (putamen, globus pallidus or thalamus and glioma is suspected, NSTB by using MRI with virtual trajectory is preferable to CTSTB concerning morbidity.

  13. Calibration and optimization of 3D digital breast tomosynthesis guided near infrared spectral tomography.

    Science.gov (United States)

    Michaelsen, Kelly E; Krishnaswamy, Venkataramanan; Shi, Linxi; Vedantham, Srinivasan; Poplack, Steven P; Karellas, Andrew; Pogue, Brian W; Paulsen, Keith D

    2015-12-01

    Calibration of a three-dimensional multimodal digital breast tomosynthesis (DBT) x-ray and non-fiber based near infrared spectral tomography (NIRST) system is challenging but essential for clinical studies. Phantom imaging results yielded linear contrast recovery of total hemoglobin (HbT) concentration for cylindrical inclusions of 15 mm, 10 mm and 7 mm with a 3.5% decrease in the HbT estimate for each 1 cm increase in inclusion depth. A clinical exam of a patient's breast containing both benign and malignant lesions was successfully imaged, with greater HbT was found in the malignancy relative to the benign abnormality and fibroglandular regions (11 μM vs. 9.5 μM). Tools developed improved imaging system characterization and optimization of signal quality, which will ultimately improve patient selection and subsequent clinical trial results.

  14. Diagnostic efficacy of computed tomography-guided transthoracic needle aspiration and biopsy in patients with pulmonary disease

    Directory of Open Access Journals (Sweden)

    Tuna T

    2013-11-01

    Full Text Available Tibel Tuna,1 Sevket Ozkaya,2 Adem Dirican,2 Serhat Findik,3 Atilla G Atici,3 Levent Erkan31Department of Pulmonary Medicine, Samsun Chest Diseases and Thoracic Surgery Hospital, 2Department of Pulmonary Medicine, Medical Park Samsun Hospital, 3Department of Pulmonary Medicine, Faculty of Medicine, Samsun Ondokuzmayis University, Samsun, TurkeyBackground: Computed tomography-guided transthoracic needle aspiration (TTNA and biopsy (TTNB is a well established, safe, and rapid method of reaching a definitive diagnosis for most thoracic lesions. The present study aimed to determine the roles of TTNA and TTNB in the diagnosis of pulmonary diseases and to compare the results using these two techniques.Methods: TTNB and TTNA were performed in 105 patients admitted to our clinic due to peripheral pulmonary lesions between May 2005 and November 2007. Needle biopsies were performed using 18-gauge Tru-Cut® biopsy needles and aspirations was performed using 18-20-22-gauge Chiba needles.Results: Malignant lesions diagnosed by TTNB were non-small cell lung carcinoma (51 patients, 73%, small cell lung carcinoma (nine patients, 13%, malignant tissue (three patients, 5%, lymphoma (two patients, 3%, thymoma (two patients, 3%, plasmacytoma (one patient, 1%, rhabdomyosarcoma (one patient, 1%, and metastasis (one patient, 1%. The malignant lesions diagnosed by TTNA were non-small cell lung carcinoma in eleven patients (92% and malignant tissue in one patient (8%. Three (100% of the benign lesions diagnosed by TTNB were granulomas and two (100% benign lesions diagnosed by TTNA were infarctions. When the diagnostic value of TTNB and TTNA was compared, TTNB was significantly superior. Malignant lesions were identified in 70 (84% and benign lesions were identified in three (4% of the 83 patients in the TTNB group. Ten (12% patients in the TTNB group could not be diagnosed. Malignant lesions were found in 12 (55% and benign lesions were found in two (9% of the 22

  15. Ultrafast cone-beam computed tomography imaging and postprocessing data during image-guided therapeutic practice

    Energy Technology Data Exchange (ETDEWEB)

    Paul, Jijo; Vogl, Thomas J. [University Hospital Frankfurt, Diagnostic and Interventional Radiology, Frankfurt/Main (Germany); Mbalisike, Emmanuel C. [Hospital of the Bad Salzungen GmbH, Diagnostic and Interventional Radiology, Bad Salzungen (Germany)

    2014-11-15

    Our objective was to evaluate ultrafast cone-beam computed tomography (u-CBCT) image data using cross-sectional images, perfusion blood volume (PBV), and image fusion during tumour detection at the course of transarterial chemoembolization. One hundred and fifty patients (63 ± 20 years; 33-82) were examined from February to October 2013 with u-CBCT. Tumour delineation and conspicuity were determined using u-CBCT cross-sectional PBV and u-CBCT-magnetic resonance imaging (MRI) fused data sets for hyperenhanced (HYET), heterogeneously enhanced (HEET), and unenhanced (UET) tumour categories. Catheter localisation and tumour feeding vessels were assessed using all data sets. Quantitative and qualitative analyses were performed using appropriate statistical tests. Qualitative and quantitative tumour delineation showed significant difference (all P < 0.05) among tumour categories. Mean tumour-liver-contrast was higher in HYET than in HEET, and UET; moreover, differences between tumour categories were statistically significant (all P < 0.0001). Fused data showed higher value with statistical significance (P < 0.05) compared with other data sets during catheter localisation and feeding-vessel identification. Tumour delineation was clearly possible using u-CBCT cross sections with contrast material. PBV uses color-coded images to increase detection and produces good tumour differentiation. Image fusion helps accurately identify tumour and feeding vessels and locate contrast material injection sites and catheter tips without additional data acquisition. (orig.)

  16. A fast atlas-guided high density diffuse optical tomography system for brain imaging

    Science.gov (United States)

    Dai, Xianjin; Zhang, Tao; Yang, Hao; Jiang, Huabei

    2017-02-01

    Near infrared spectroscopy (NIRS) is an emerging functional brain imaging tool capable of assessing cerebral concentrations of oxygenated hemoglobin (HbO) and deoxygenated hemoglobin (HbR) during brain activation noninvasively. As an extension of NIRS, diffuse optical tomography (DOT) not only shares the merits of providing continuous readings of cerebral oxygenation, but also has the ability to provide spatial resolution in the millimeter scale. Based on the scattering and absorption properties of nonionizing near-infrared light in biological tissue, DOT has been successfully applied in the imaging of breast tumors, osteoarthritis and cortex activations. Here, we present a state-of-art fast high density DOT system suitable for brain imaging. It can achieve up to a 21 Hz sampling rate for a full set of two-wavelength data for 3-D DOT brain image reconstruction. The system was validated using tissue-mimicking brain-model phantom. Then, experiments on healthy subjects were conducted to demonstrate the capability of the system.

  17. Optical coherence tomography-guided laser microsurgery for blood coagulation with continuous-wave laser diode

    Science.gov (United States)

    Chang, Feng-Yu; Tsai, Meng-Tsan; Wang, Zu-Yi; Chi, Chun-Kai; Lee, Cheng-Kuang; Yang, Chih-Hsun; Chan, Ming-Che; Lee, Ya-Ju

    2015-11-01

    Blood coagulation is the clotting and subsequent dissolution of the clot following repair to the damaged tissue. However, inducing blood coagulation is difficult for some patients with homeostasis dysfunction or during surgery. In this study, we proposed a method to develop an integrated system that combines optical coherence tomography (OCT) and laser microsurgery for blood coagulation. Also, an algorithm for positioning of the treatment location from OCT images was developed. With OCT scanning, 2D/3D OCT images and angiography of tissue can be obtained simultaneously, enabling to noninvasively reconstruct the morphological and microvascular structures for real-time monitoring of changes in biological tissues during laser microsurgery. Instead of high-cost pulsed lasers, continuous-wave laser diodes (CW-LDs) with the central wavelengths of 450 nm and 532 nm are used for blood coagulation, corresponding to higher absorption coefficients of oxyhemoglobin and deoxyhemoglobin. Experimental results showed that the location of laser exposure can be accurately controlled with the proposed approach of imaging-based feedback positioning. Moreover, blood coagulation can be efficiently induced by CW-LDs and the coagulation process can be monitored in real-time with OCT. This technology enables to potentially provide accurate positioning for laser microsurgery and control the laser exposure to avoid extra damage by real-time OCT imaging.

  18. Optical coherence tomography-guided laser microsurgery for blood coagulation with continuous-wave laser diode.

    Science.gov (United States)

    Chang, Feng-Yu; Tsai, Meng-Tsan; Wang, Zu-Yi; Chi, Chun-Kai; Lee, Cheng-Kuang; Yang, Chih-Hsun; Chan, Ming-Che; Lee, Ya-Ju

    2015-11-16

    Blood coagulation is the clotting and subsequent dissolution of the clot following repair to the damaged tissue. However, inducing blood coagulation is difficult for some patients with homeostasis dysfunction or during surgery. In this study, we proposed a method to develop an integrated system that combines optical coherence tomography (OCT) and laser microsurgery for blood coagulation. Also, an algorithm for positioning of the treatment location from OCT images was developed. With OCT scanning, 2D/3D OCT images and angiography of tissue can be obtained simultaneously, enabling to noninvasively reconstruct the morphological and microvascular structures for real-time monitoring of changes in biological tissues during laser microsurgery. Instead of high-cost pulsed lasers, continuous-wave laser diodes (CW-LDs) with the central wavelengths of 450 nm and 532 nm are used for blood coagulation, corresponding to higher absorption coefficients of oxyhemoglobin and deoxyhemoglobin. Experimental results showed that the location of laser exposure can be accurately controlled with the proposed approach of imaging-based feedback positioning. Moreover, blood coagulation can be efficiently induced by CW-LDs and the coagulation process can be monitored in real-time with OCT. This technology enables to potentially provide accurate positioning for laser microsurgery and control the laser exposure to avoid extra damage by real-time OCT imaging.

  19. Optical coherence tomography angiography of retinal vascular occlusions produced by imaging-guided laser photocoagulation

    Science.gov (United States)

    Soetikno, Brian T.; Shu, Xiao; Liu, Qi; Liu, Wenzhong; Chen, Siyu; Beckmann, Lisa; Fawzi, Amani A.; Zhang, Hao F.

    2017-01-01

    Retinal vascular occlusive diseases represent a major form of vision loss worldwide. Rodent models of these diseases have traditionally relied upon a slit-lamp biomicroscope to help visualize the fundus and subsequently aid delivery of high-power laser shots to a target vessel. Here we describe a multimodal imaging system that can produce, image, and monitor retinal vascular occlusions in rodents. The system combines a spectral-domain optical coherence tomography system for cross-sectional structural imaging and three-dimensional angiography, and a fluorescence scanning laser ophthalmoscope for Rose Bengal monitoring and high-power laser delivery to a target vessel. This multimodal system facilitates the precise production of occlusions in the branched retinal veins, central retinal vein, and branched retinal arteries. Additionally, changes in the retinal morphology and retinal vasculature can be longitudinally documented. With our device, retinal vascular occlusions can be easily and consistently created, which paves the way for futures studies on their pathophysiology and therapeutic targets. PMID:28856036

  20. Computed-tomography-guided high-dose-rate brachytherapy (CT-HDRBT) ablation of metastases adjacent to the liver hilum.

    Science.gov (United States)

    Collettini, Federico; Singh, Anju; Schnapauff, Dirk; Powerski, Maciej Janusz; Denecke, Timm; Wust, Peter; Hamm, Bernd; Gebauer, Bernhard

    2013-10-01

    To evaluate technical feasibility and clinical outcome of computed tomography-guided high-dose-rate-brachytherapy (CT-HDRBT) ablation of metastases adjacent to the liver hilum. Between November 2007 and May 2012, 32 consecutive patients with 34 metastases adjacent to the liver hilum (common bile duct or hepatic bifurcation ≤5 mm distance) were treated with CT-HDRBT. Treatment was performed by CT-guided applicator placement and high-dose-rate brachytherapy with an iridium-192 source. MRI follow-up was performed 6 weeks and every 3 months post intervention. The primary endpoint was local tumor control (LTC); secondary endpoints included time to progression (TTP) and overall survival (OS). Patients were available for MRI evaluation for a mean follow-up time of 18.75 months (range: 3-56 months). Mean tumor diameter was 4.3 cm (range: 1.3-10.7 cm). One major complication was observed. Four (11.8%) local recurrences were observed after a local tumor control of 5, 8, 9 and 10 months, respectively. Twenty-two patients (68.75%) experienced a systemic tumor progression during the follow up period. Mean TTP was 12.9 months (range: 2-56 months). Nine patients died during the follow-up period. Median OS was 20.24 months. Minimally invasive CT-HDRBT is a safe and effective option also for unresectable liver metastases adjacent to the liver hilum that would have been untreatable by thermal ablation. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  1. Computed-tomography-guided high-dose-rate brachytherapy (CT-HDRBT) ablation of metastases adjacent to the liver hilum

    Energy Technology Data Exchange (ETDEWEB)

    Collettini, Federico, E-mail: federico.collettini@charite.de [Department of Radiology, Charité Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin (Germany); Department of Radiation Oncology, Charité – Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin (Germany); Singh, Anju [Department of Medical Oncology, Charité – Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin (Germany); Schnapauff, Dirk [Department of Radiology, Charité – Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin (Germany); Department of Radiation Oncology, Charité – Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin (Germany); Powerski, Maciej Janusz [Charité – Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203 Berlin (Germany); Department of Radiation Oncology, Charité – Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin (Germany); and others

    2013-10-01

    Purpose: To evaluate technical feasibility and clinical outcome of computed tomography-guided high-dose-rate-brachytherapy (CT-HDRBT) ablation of metastases adjacent to the liver hilum. Materials and methods: Between November 2007 and May 2012, 32 consecutive patients with 34 metastases adjacent to the liver hilum (common bile duct or hepatic bifurcation ≤5 mm distance) were treated with CT-HDRBT. Treatment was performed by CT-guided applicator placement and high-dose-rate brachytherapy with an iridium-192 source. MRI follow-up was performed 6 weeks and every 3 months post intervention. The primary endpoint was local tumor control (LTC); secondary endpoints included time to progression (TTP) and overall survival (OS). Results: Patients were available for MRI evaluation for a mean follow-up time of 18.75 months (range: 3–56 months). Mean tumor diameter was 4.3 cm (range: 1.3–10.7 cm). One major complication was observed. Four (11.8%) local recurrences were observed after a local tumor control of 5, 8, 9 and 10 months, respectively. Twenty-two patients (68.75%) experienced a systemic tumor progression during the follow up period. Mean TTP was 12.9 months (range: 2–56 months). Nine patients died during the follow-up period. Median OS was 20.24 months. Conclusion: Minimally invasive CT-HDRBT is a safe and effective option also for unresectable liver metastases adjacent to the liver hilum that would have been untreatable by thermal ablation.

  2. The combination of digital surface scanners and cone beam computed tomography technology for guided implant surgery using 3Shape implant studio software: a case history report.

    Science.gov (United States)

    Lanis, Alejandro; Álvarez Del Canto, Orlando

    2015-01-01

    The incorporation of virtual engineering into dentistry and the digitization of information are providing new perspectives and innovative alternatives for dental treatment modalities. The use of digital surface scanners with surgical planning software allows for the combination of the radiographic, prosthetic, surgical, and laboratory fields under a common virtual scenario, permitting complete digital treatment planning. In this article, the authors present a clinical case in which a guided implant surgery was performed based on a complete digital surgical plan combining the information from a cone beam computed tomography scan and the virtual simulation obtained from the 3Shape TRIOS intraoral surface scanner. The information was imported to and combined in the 3Shape Implant Studio software for guided implant surgery planning. A surgical guide was obtained by a 3D printer, and the surgical procedure was done using the Biohorizons Guided Surgery Kit and its protocol.

  3. NDT-COMP9 microcomputer

    Energy Technology Data Exchange (ETDEWEB)

    Dodd, C.V.; Cowan, R.F.

    1980-09-01

    An 8080-based microcomputer system, the NDT-COMP9, has been designed for instrumentation control and data analysis in eddy-current tests. The NDT-COMP9 represents a significantly more powerful computer system than the NDT-COMP8 microcomputer from which it was developed. The NDT-COMP9 system is contained on a 240- by 120-mm (9.5- by 4.8-in.) circuit board and will fit in a four-wide Nuclear Instrumentation Module (NIM) BIN with 26-pin edge connectors. In addition to the 8080-compatible central processing unit (CPU), an arithmetic processing unit (APU) is available to provide up to 32-bit fixed- or floating-point, basic or transcendental math functions. The 16K of read only memory (ROM) and random access memory (RAM), one serial input-output (I/O) port (RS-232-C at a maximum speed of 9600 baud), and 72 parallel I/O ports are available. The baud rate is under software control. A system monitor and math package are available for use with the microcomputer.

  4. Fluoroscopy-Guided Sacroplasty: Special Focus on Preoperative Planning from Three-Dimensional Computed Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Gjertsen, Oe.; Schellhorn, T.; Nakstad, P.H. (Dept. of Neuroradiology, Division of Medical Services, Ullevl Univ. Hospital, Univ. of Oslo, Oslo (Norway))

    2008-11-15

    Background: Osteoporotic sacral insufficiency fractures are usually spontaneous or caused by discrete traumas. The fluoroscopic anatomy of the sacrum can be difficult to understand, and this is why sacroplasty is considered more challenging than ordinary vertebroplasties. Purpose: To demonstrate the planning of the procedure and the effectiveness of treatment with sacroplasty by means of three-dimensional computed tomography (3D CT) by combining multiplanar reconstructions (MPR) and volume-rendering technique (VRT). Material and Methods: Five elderly, osteoporotic patients with intense pelvic and hip pain underwent weeks of inconclusive clinical and radiological diagnostic efforts. Correct diagnosis was finally attained with magnetic resonance imaging (MRI) and CT. Plain radiographs rarely show fractures, and MR or CT examinations are necessary to demonstrate longitudinal fractures. The procedures were performed with digital biplane equipment using preoperative 3D CT planning procedures. Polymethyl methacrylate (PMMA) was injected to fill the fracture sites. Results: The fractures were successfully treated with sacroplasty using PMMA. A new technique, which involves placing the needles along the long axis of the sacrum, was optimized to the individual patients' fractures and sacral anatomy by meticulous planning on a workstation with 3D CT data sets. It was technically successful in all five cases. Four of the five patients had sustained pain relief. Conclusion: Sacral insufficiency fractures are not uncommon and should be considered in the elderly population with low back pain. Sacroplasty using the optimized 'long-axis technique' gave almost immediate pain relief for all five patients in our study material. No complications were observed.

  5. Real-time 3D Fourier-domain optical coherence tomography guided microvascular anastomosis

    Science.gov (United States)

    Huang, Yong; Ibrahim, Zuhaib; Lee, W. P. A.; Brandacher, Gerald; Kang, Jin U.

    2013-03-01

    Vascular and microvascular anastomosis is considered to be the foundation of plastic and reconstructive surgery, hand surgery, transplant surgery, vascular surgery and cardiac surgery. In the last two decades innovative techniques, such as vascular coupling devices, thermo-reversible poloxamers and suture-less cuff have been introduced. Intra-operative surgical guidance using a surgical imaging modality that provides in-depth view and 3D imaging can improve outcome following both conventional and innovative anastomosis techniques. Optical coherence tomography (OCT) is a noninvasive high-resolution (micron level), high-speed, 3D imaging modality that has been adopted widely in biomedical and clinical applications. In this work we performed a proof-of-concept evaluation study of OCT as an assisted intraoperative and post-operative imaging modality for microvascular anastomosis of rodent femoral vessels. The OCT imaging modality provided lateral resolution of 12 μm and 3.0 μm axial resolution in air and 0.27 volume/s imaging speed, which could provide the surgeon with clearly visualized vessel lumen wall and suture needle position relative to the vessel during intraoperative imaging. Graphics processing unit (GPU) accelerated phase-resolved Doppler OCT (PRDOCT) imaging of the surgical site was performed as a post-operative evaluation of the anastomosed vessels and to visualize the blood flow and thrombus formation. This information could help surgeons improve surgical precision in this highly challenging anastomosis of rodent vessels with diameter less than 0.5 mm. Our imaging modality could not only detect accidental suture through the back wall of lumen but also promptly diagnose and predict thrombosis immediately after reperfusion. Hence, real-time OCT can assist in decision-making process intra-operatively and avoid post-operative complications.

  6. Prosthesis-guided implant restoration of an auricular defect using computed tomography and 3-dimensional photographic imaging technologies: a clinical report.

    Science.gov (United States)

    Wang, Shuming; Leng, Xu; Zheng, Yaqi; Zhang, Dapeng; Wu, Guofeng

    2015-02-01

    The concept of prosthesis-guided implantation has been widely accepted for intraoral implant placement, although clinicians do not fully appreciate its use for facial defect restoration. In this clinical report, multiple digital technologies were used to restore a facial defect with prosthesis-guided implantation. A simulation surgery was performed to remove the residual auricular tissue and to ensure the correct position of the mirrored contralateral ear model. The combined application of computed tomography and 3-dimensional photography preserved the position of the mirrored model and facilitated the definitive implant-retained auricular prosthesis.

  7. Computed tomography-guided implant surgery for dental rehabilitation in mandible reconstructed with a fibular free flap: description of the technique.

    Science.gov (United States)

    De Riu, Giacomo; Meloni, Silvio Mario; Pisano, Milena; Massarelli, Olindo; Tullio, Antonio

    2012-01-01

    The fibular free flap, with or without a cutaneous component, is the gold standard for reconstructing mandibular defects. Dental prosthetic rehabilitation is possible this way, even if the prosthesis-based implant is still a challenge because of the many anatomical and prosthetic problems. We think that complications can be overcome or reduced by adopting the new methods of computed tomography (CT)-assisted implant surgery (NobelGuide, Nobel Biocare AB, Goteborg, Sweden). Here we describe the possibility of using CT-guided implant surgery with a flapless approach and immediate loading in mandibles reconstructed with fibular free flaps.

  8. Microcomputer Checks Butt-Weld Accuracy

    Science.gov (United States)

    Clisham, W.; Garner, W.; Cohen, C.; Beal, J.; Polen, R.; Lloyd, J.

    1982-01-01

    Electrical gage and microcomputer eliminate time-consuming manual measurements. Alinement and angle of plates on either side of butt weld are measured and recorded automatically by hand-held gage and desk-top microcomputer. Gage/micro-computer quickly determine whether weld is within dimensional tolerances or whether reworking is needed. Microcomputer prints out measurements while operator moves gage from point to point along weld. Out-of-tolerance measurements are marked by an asterisk on printout.

  9. The use of computerised tomography guided percutaneous fine needle aspiration in the evaluation of solitary pulmonary nodules.

    LENUS (Irish Health Repository)

    Khan, K A

    2012-02-01

    The evaluation of a solitary pulmonary nodule (SPN) has changed over the years with increased access to percutaneous computerised tomography (CT) guided fine needle aspiration (FNA), where bronchoscopy is unhelpful. The aim of our study was to evaluate the sample adequacy, diagnostic and complication rate of CT-FNA of a SPN at our academic teaching hospital over an 18 month period. CT-FNA was performed by a radiologist, with a cytopathologist in attendance to confirm the adequacy of the sample obtained. The size of the nodule, sample material and adequacy, diagnosis and complications were recorded. A total of 101 patients were included, 54 male and the mean age was 68 +\\/- 11 years. The mean size of the SPN was 2.3 cm (range 1-11 cm). 56 (56%) patients had a right SPN, 45 (45%) had a left SPN. CT-FNA was diagnostic in 80 (80%) patients and non-diagnostic in 21 (20%) patients. The sample was insufficient for immunocytochemistry, although the morphological appearance was diagnostic in 20 (25%) of the 80 patients. Pneumothorax occurred in 26\\/101 (26%) patients post CT-FNA, of these 7 (27%) required chest drain insertion, while 19 (73%) were managed conservatively. CT FNA is a useful tool for the diagnosis of a SPN, with our diagnostic accuracy comparable to that reported in the literature. However, CT-FNA may not provide adequate sample volume to perform ancillary testing and has a moderate complication rate.

  10. The use of computerised tomography guided percutaneous fine needle aspiration in the evaluation of solitary pulmonary nodules.

    LENUS (Irish Health Repository)

    Khan, K A

    2012-02-01

    The evaluation of a solitary pulmonary nodule (SPN) has changed over the years with increased access to percutaneous computerised tomography (CT) guided fine needle aspiration (FNA), where bronchoscopy is unhelpful. The aim of our study was to evaluate the sample adequacy, diagnostic and complication rate of CT-FNA of a SPN at our academic teaching hospital over an 18 month period. CT-FNA was performed by a radiologist, with a cytopathologist in attendance to confirm the adequacy of the sample obtained. The size of the nodule, sample material and adequacy, diagnosis and complications were recorded. A total of 101 patients were included, 54 male and the mean age was 68 +\\/- 11 years. The mean size of the SPN was 2.3 cm (range 1-11 cm). 56 (56%) patients had a right SPN, 45 (45%) had a left SPN. CT-FNA was diagnostic in 80 (80%) patients and non-diagnostic in 21 (20%) patients. The sample was insufficient for immunocytochemistry, although the morphological appearance was diagnostic in 20 (25%) of the 80 patients. Pneumothorax occurred in 26\\/101 (26%) patients post CT-FNA, of these 7 (27%) required chest drain insertion, while 19 (73%) were managed conservatively. CT FNA is a useful tool for the diagnosis of a SPN, with our diagnostic accuracy comparable to that reported in the literature. However, CT-FNA may not provide adequate sample volume to perform ancillary testing and has a moderate complication rate.

  11. Four-Dimensional (4D) Printing: A New Evolution in Computed Tomography-Guided Stereolithographic Modeling. Principles and Application.

    Science.gov (United States)

    Chae, Michael P; Hunter-Smith, David J; De-Silva, Inoka; Tham, Stephen; Spychal, Robert T; Rozen, Warren Matthew

    2015-07-01

    Over the last decade, image-guided production of three-dimensional (3D) haptic biomodels, or rapid prototyping (RP), has transformed the way surgeons conduct preoperative planning. In contrast to earlier RP techniques such as stereolithography, 3D printing has introduced fast, affordable office-based manufacturing. We introduce the concept of 4D printing for the first time by introducing time as the fourth dimension to 3D printing. The bones of the thumb ray are 3D printed during various movements to demonstrate four-dimensional (4D) printing. Principles and validation studies are presented here. 4D computed tomography was performed using "single volume acquisition" technology to reduce the exposure to radiation. Three representative scans of each thumb movement (i.e., abduction, opposition, and key pinch) were selected and then models were fabricated using a 3D printer. For validation, the angle between the first and the second metacarpals from the 4D imaging data and the 4D-printed model was recorded and compared. We demonstrate how 4D printing accurately depicts the transition in the position of metacarpals during thumb movement. With a fourth dimension of time, 4D printing delivers complex spatiotemporal anatomical details effortlessly and may substantially improve preoperative planning. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  12. Computed tomography-guided needle aspiration and biopsy of pulmonary lesions - A single-center experience in 1000 patients

    Energy Technology Data Exchange (ETDEWEB)

    Poulou, Loukia S.; Tsagouli, Paraskevi; Thanos, Loukas [Dept. of Medical Imaging and Interventional Radiology, General Hospital of Chest Diseases ' Sotiria' , Athens (Greece)], e-mail: ploukia@hotmail.com; Ziakas, Panayiotis D. [Program of Outcomes Research, Div. of Infectious Diseases, Warren Alpert Medical School, Brown Univ., RI, and Div. of Infectious Diseases, Rhode Island Hospital, Rhode Island (United States); Politi, Dimitra [Dept. of Cythopathology, General Hospital of Chest Diseases ' Sotiria' Athens (Greece); Trigidou, Rodoula [Dept. of Pathology, General Hospital of Chest Diseases ' Sotiria' Athens (Greece)

    2013-07-15

    Background: Computed tomography (CT)-guided fine needle aspiration (FNA) and biopsies are well-established, minimally invasive diagnostic tools for pulmonary lesions. Purpose: To analyze retrospectively the results of 1000 consecutive lung CT-guided FNA and/or core needle biopsies (CNB), the main outcome measures being diagnostic yield, and complication rates. Material and Methods: Patients considered eligible were those referred to our department for lung lesions. The choice of FNA, CNB, or both was based upon the radiologist's judgment. Diagnostic yield was defined as the probability of having a definite result by cytology/histology. Results: The study included 733 male patients and 267 female patients, with a mean (SD) age of 66.4 (11.4) years. The mean (SD) lesion size was 3.7 (2.4) cm in maximal diameter. Six hundred and forty-one (64%) patients underwent an FNA procedure, 245 (25%) a CNB, and 114 (11%) had been subjected to both. The diagnostic yield was 960/994 (96.6%); this decreased significantly with the use of CNB only (odds ratio [OR] 0.32; 95% CI 0.12 - 0.88; P = 0.03), while it increased with lesion size (OR 1.35; 95% CI 1.03 - 1.79; P = 0.03 per cm increase). In 506 patients (52.7%), a malignant process was diagnosed by cytopathology/histology. The complication rate reached 97/1000 (9.7%); complications included: hemorrhage, 62 (6.2%); pneumothorax, 28 (2.8%); hemorrhage and pneumothorax, 5 (0.5%); and hemoptysis, 2 (0.2%). It was not significantly affected by the type of procedure or localization of the lesion. The overall risk for complications was three times higher for lesions <4 cm (OR 3.26; 95% CI 1.96 - 5.42; P < 0.001). Conclusion: CT-guided lung biopsy has a high diagnostic yield using FNA, CNB, or both. The CNB procedure alone will not suffice. Complication rates were acceptable and correlated inversely with lesion size, not localization or type of procedure.

  13. Optical coherence tomography image-guided smart laser knife for surgery.

    Science.gov (United States)

    Katta, Nitesh; McElroy, Austin B; Estrada, Arnold D; Milner, Thomas E

    2017-08-07

    Surgical oncology can benefit from specialized tools that enhance imaging and enable precise cutting and removal of tissue without damage to adjacent structures. The combination of high-resolution, fast optical coherence tomography (OCT) co-aligned with a nanosecond pulsed thulium (Tm) laser offers advantages over conventional surgical laser systems. Tm lasers provide superior beam quality, high volumetric tissue removal rates with minimal residual thermal footprint in tissue, enabling a reduction in unwanted damage to delicate adjacent sub-surface structures such as nerves or micro-vessels. We investigated such a combined Tm/OCT system with co-aligned imaging and cutting beams-a configuration we call a "smart laser knife." A blow-off model that considers absorption coefficients and beam delivery systems was utilized to predict Tm cut depth, tissue removal rate and spatial distribution of residual thermal injury. Experiments were performed to verify the volumetric removal rate predicted by the model as a function of average power. A bench-top, combined Tm/OCT system was constructed using a 15W 1940 nm nanosecond pulsed Tm fiber laser (500 μJ pulse energy, 100 ns pulse duration, 30 kHz repetition rate) for removing tissue and a swept source laser (1310 ± 70 nm, 100 kHz sweep rate) for OCT imaging. Tissue phantoms were used to demonstrate precise surgery with blood vessel avoidance. Depth imaging informed cutting/removal of targeted tissue structures by the Tm laser was performed. Laser cutting was accomplished around and above phantom blood vessels while avoiding damage to vessel walls. A tissue removal rate of 5.5 mm(3) /sec was achieved experimentally, in comparison to the model prediction of approximately 6 mm(3) /sec. We describe a system that combines OCT and laser tissue modification with a Tm laser. Simulation results of the tissue removal rate using a simple model, as a function of average power, are in good agreement with experimental

  14. Spinal epidural abscess successfully treated with percutaneous, computed tomography-guided, needle aspiration and parenteral antibiotic therapy: case report and review of the literature.

    Science.gov (United States)

    Lyu, Rong-Kuo; Chen, Chi-Jen; Tang, Lok-Ming; Chen, Sien-Tsong

    2002-08-01

    We describe a case of a posterior spinal epidural abscess that was successfully treated with percutaneous, computed tomography-guided, needle aspiration and parenteral antibiotic therapy. A 48-year-old man experienced acute pain in the paralumbar region for 1 week, followed by gait disturbance and micturition difficulty. Laboratory studies demonstrated leukocytosis and hyperglycemia. Blood cultures yielded Staphylococcus aureus. Magnetic resonance imaging scans of the thoracolumbar spine revealed a posterior spinal epidural abscess located between L2 and the lower cervical spine. The patient's low back pain persisted despite 10 days of antibiotic therapy. Therefore, percutaneous, computed tomography-guided, needle aspiration was performed. The low back pain was relieved dramatically and immediately after the procedure. The spinal epidural abscess completely resolved after 6 weeks of antibiotic treatment. Surgical decompression and antibiotic therapy are the treatments of choice for patients with spinal epidural abscesses. Selected patients may be treated nonsurgically. Rarely, percutaneous drainage of the abscess has been reported to be helpful. Our case suggests that percutaneous, computed tomography-guided, needle aspiration might be a rational alternative to surgical decompression for treatment of spinal epidural abscesses.

  15. Macular laser photocoagulation guided by spectral-domain optical coherence tomography versus fluorescein angiography for diabetic macular edema

    Directory of Open Access Journals (Sweden)

    Gallego-Pinazo R

    2011-05-01

    Full Text Available Roberto Gallego-Pinazo1,2, Ana Marina Suelves-Cogollos1, Rosa Dolz-Marco1, J Fernando Arevalo3, Salvador García-Delpech1, J Luis Mullor4, Manuel Díaz-Llopis1,2,51Department of Ophthalmology, Hospital Universitario La Fe, Valencia, Spain; 2Centro de Investigación Biomédica en Red de Enfermedades Raras, Valencia, Spain; 3Retina and Vitreous Service, Clinical Ophthalmology Center, Caracas, Venezuela; 4Unit of Experimental Ophthalmology, Hospital Universitario La Fe, Valencia, Spain; 5University of Valencia, Faculty of Medicine, Valencia, SpainBackground: The aim of this study was to compare the efficacy of spectral-domain optical coherence tomography (SD-OCT and fluorescein angiography (FA in the guidance of macular laser photocoagulation for diabetic macular edema.Methods: This was a prospective interventional clinical comparative pilot study. Forty eyes from 24 consecutive patients with diabetic macular edema were allocated to receive laser photocoagulation guided by SD-OCT or FA. Best-corrected visual acuity (BCVA, central macular thickness, and retinal volume were assessed at baseline and two months after treatment.Results: Subjects treated using FA-guided laser improved BCVA from the logarithm of the minimum angle of resolution (logMAR 0.52 ± 0.2 to 0.37 ± 0.2 (P < 0.001, and decreased mean central macular thickness from 397.25 ± 139.1 to 333.50 ± 105.7 µm (P < 0.001 and retinal volume from 12.61 ± 1.6 to 10.94 ± 1.4 mm3 (P < 0.001. Subjects treated using SD-OCT guided laser had improved BCVA from 0.48 ± 0.2 to 0.33 ± 0.2 logMAR (P < 0.001, and decreased mean central macular thickness from 425.90 ± 149.6 to 353.4 ± 140 µm (P < 0.001 and retinal volume from 12.38 ± 2.1 to 11.53 ± 1.1 mm3 (P < 0.001. No significant differences between the groups were found in two-month BCVA (P = 0.505, two-month central macular thickness (P = 0.660, or two-month retinal volume (P = 0.582.Conclusion: The short-term results of this pilot study

  16. [Computerized tomography guided biopsy in the diagnosis of neoplastic and inflammatory lesions of the pelvis].

    Science.gov (United States)

    Rimondi, E; Busacca, M; Moio, A; Molinari, M; Nigrisoli, M; Trentani, F; Trentani, P; Tigani, D

    2001-01-01

    To assess the efficacy of percutaneous CT-guided biopsy in the diagnosis and therapeutic planning of neoplastic and flogistic diseases of the pelvis. From July 1990 to December 1999 193 patients (113 males, 80 females: mean age 49, standard deviation 16) were submitted to CT-guided percutaneous biopsy of the pelvic region; 117 biopsies (61%) were performed at iliac, pubic and ischial segments and 76 (39%) at sacral region; 107 patients were admitted to the hospital and 86 were in clinic. Needles were 8 G (4 mm), 10 to 15 cm long. Approach to pelvic lesions was performed according to the specific site. Lesions of the lateral pelvic region have always been approached through the lateral surgical incision according to Enneking. Lesions of the posterior pelvic region have always been approached by the introduction of the needle along the posterior surgical incision according to Enneking. Lesions of the anterior region have always been approached through the anterior surgical incision according to Enneking. From July 1990 to May 1997 pelvic percutaneous biopsies have been carried out with a CT Sytec 3000. From May 1997 to December 1999 the device was replaced by a High Speed CTi. The introduction of spiral CT allowed reduction of performance mean time from 45 minutes (standard deviation 15) to 30 minutes (standard deviation 10). In 154 patients (80%) we observed a neoplastic, inflammatory or not classified degeneration. In 8 patients (4%) the retrieved material ended to be inadequate for a diagnosis. In 31 patients (16%) no disease was revealed at the histological examination. Such patients with negative histological examination have been kept under clinical and radiological control in the following period in order to verify the manifestation or the presence of an alteration previously not observed. On 31-3-2000 none of them had been submitted to a new percutaneous biopsy of the pelvic region. The overall mean accuracy has been 96% considering the negative patients as

  17. Biopsy system guided by positron emission tomography in real-time

    Science.gov (United States)

    Moliner, L.; Álamo, J.; Hellingman, D.; Peris, J. L.; Gomez, J.; Tattersall, P.; Carrilero, V.; Orero, A.; Correcher, C.; Benlloch, J. M.

    2016-03-01

    In this work we present the MAMMOCARE prototype, a biopsy guided system based on PET. The system is composed by an examination table where the patient is situated in prone position, a PET detector and a biopsy device. The PET detector is composed by two rings. These rings can be separated mechanically in order to allow the needle insertion. The first acquisition is performed with the closed ring configuration in order to obtain a high quality image to locate the lesion. Then, the software calculates the optimum path for the biopsy and moves the biopsy and PET systems to the desired position. At this point, two compression pallets are used to hold the breast. Then, the PET system opens and the biopsy procedure starts. The images are obtained at several steps to ensure the correct location of the needle during the procedure. The performance of the system is evaluated measuring the spatial resolution and sensitivity according the NEMA standard. The uniformity of the reconstructed images is also estimated. The radial resolution is 1.62mm in the center of the FOV and 3.45mm at 50mm off the center in the radial direction using the closed configuration. In the open configuration the resolution reaches 1.85mm at center and 3.65mm at 50mm. The sensitivity using an energy window of 250keV-750keV is 3.6% for the closed configuration and 2.5% for the open configuration. The uniformity measured in the center of the FOV is 14% and 18% for the closed and open configurations respectively.

  18. Successful treatment of a free-moving abdominal mass with radiation therapy guided by cone-beam computed tomography: a case report

    Directory of Open Access Journals (Sweden)

    Shihadeh Ferial

    2010-10-01

    Full Text Available Abstract Introduction Because tumors in the abdomen can change position, targeting these tumors for radiation therapy should be done with caution; use of daily image-guided radiation therapy is advised. Case presentation We report the case of a 72-year-old Caucasian man with recurrent mantle cell lymphoma who was referred for palliative radiation therapy for an abdominopelvic tumor. Computed tomography was used to generate images for radiation treatment planning. Comparison of those planning images with a positron emission tomography/computed tomography scan ordered during the planning period revealed that the tumor had moved from one side of the abdomen to the other during the three-day interval between scans. To account for this unusual tumor movement, we obtained a second set of planning computed tomography scans and used a Varian cone-beam computed tomography scanner with on-board imaging capability to target the tumor before each daily treatment session, leading to successful treatment and complete resolution of the mass. Conclusion Abdominal masses associated with the mesentery should be considered highly mobile; thus, radiation therapy for such masses should be used with the utmost caution. Modern radiation therapy techniques offer the ability to verify the tumor location in real time and shift the treatment ports accordingly over the course of treatment.

  19. Computed tomography-guided percutaneous trephine removal of the nidus in osteoid osteoma patients: experience of a single center in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Petrilli, Marcelo; Senerchia, Andreza Almeida; Petrilli, Antonio Sergio; Lederman, Henrique Manoel; Garcia Filho, Reynaldo Jesus, E-mail: andrezasenerchia@hotmail.com [Universidade Federal de Sao Paulo (UNIFESP), Sao Paulo, SP (Brazil). Instituto de Oncologia Pediatrica

    2015-07-15

    Objective: to report the results of computed tomography (CT)-guided percutaneous resection of the nidus in 18 cases of osteoid osteoma. Materials and methods: the medical records of 18 cases of osteoid osteoma in children, adolescents and young adults, who underwent CT-guided removal of the nidus between November, 2004 and March, 2009 were reviewed retrospectively for demographic data, lesion site, clinical outcome and complications after procedure. Results: clinical follow-up was available for all cases at a median of 29 months (range 6-60 months). No persistence of pre-procedural pain was noted on 17 patients. Only one patient experienced recurrence of symptoms 12 months after percutaneous resection, and was successfully retreated by the same technique, resulting in a secondary success rate of 18/18 (100%). Conclusion: CT-guided removal or destruction of the nidus is a safe and effective alternative to surgical resection of the osteoid osteoma nidus. (author)

  20. Automating Relational Database Design for Microcomputer Users.

    Science.gov (United States)

    Pu, Hao-Che

    1991-01-01

    Discusses issues involved in automating the relational database design process for microcomputer users and presents a prototype of a microcomputer-based system (RA, Relation Assistant) that is based on expert systems technology and helps avoid database maintenance problems. Relational database design is explained and the importance of easy input…

  1. Dosimetric consequences of the shift towards computed tomography guided target definition and planning for breast conserving radiotherapy

    Directory of Open Access Journals (Sweden)

    Korevaar Erik W

    2008-01-01

    Full Text Available Abstract Background The shift from conventional two-dimensional (2D to three-dimensional (3D-conformal target definition and dose-planning seems to have introduced volumetric as well as geometric changes. The purpose of this study was to compare coverage of computed tomography (CT-based breast and boost planning target volumes (PTV, absolute volumes irradiated, and dose delivered to the organs at risk with conventional 2D and 3D-conformal breast conserving radiotherapy. Methods Twenty-five patients with left-sided breast cancer were subject of CT-guided target definition and 3D-conformal dose-planning, and conventionally defined target volumes and treatment plans were reconstructed on the planning CT. Accumulated dose-distributions were calculated for the conventional and 3D-conformal dose-plans, taking into account a prescribed dose of 50 Gy for the breast plans and 16 Gy for the boost plans. Results With conventional treatment plans, CT-based breast and boost PTVs received the intended dose in 78% and 32% of the patients, respectively, and smaller volumes received the prescribed breast and boost doses compared with 3D-conformal dose-planning. The mean lung dose, the volume of the lungs receiving > 20 Gy, the mean heart dose, and volume of the heart receiving > 30 Gy were significantly less with conventional treatment plans. Specific areas within the breast and boost PTVs systematically received a lower than intended dose with conventional treatment plans. Conclusion The shift towards CT-guided target definition and planning as the golden standard for breast conserving radiotherapy has resulted in improved target coverage at the cost of larger irradiated volumes and an increased dose delivered to organs at risk. Tissue is now included into the breast and boost target volumes that was never explicitly defined or included with conventional treatment. Therefore, a coherent definition of the breast and boost target volumes is needed, based on

  2. Computed Tomography Number Changes Observed During Computed Tomography–Guided Radiation Therapy for Head and Neck Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Mei [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Department of Radiation Oncology, Sichuan Cancer Hospital, Chengdu (China); Yang, Cungeng; Chen, Xiaojian; Xu, Shouping; Moraru, Ion [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Lang, Jinyi [Department of Radiation Oncology, Sichuan Cancer Hospital, Chengdu (China); Schultz, Christopher [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Li, X. Allen, E-mail: ali@mcw.edu [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin (United States)

    2015-04-01

    Purpose: To investigate CT number (CTN) changes in gross tumor volume (GTV) and organ at risk (OAR) according to daily diagnostic-quality CT acquired during CT-guided intensity modulated radiation therapy for head and neck cancer (HNC) patients. Methods and Materials: Computed tomography scans acquired using a CT-on-rails during daily CT-guided intensity modulated radiation therapy for 15 patients with stage II to IVa squamous cell carcinoma of the head and neck were analyzed. The GTV, parotid glands, spinal cord, and nonspecified tissue were generated on each selected daily CT. The changes in CTN distributions and the mean and mode values were collected. Pearson analysis was used to assess the correlation between the CTN change, organ volume reduction, and delivered radiation dose. Results: Volume and CTN changes for GTV and parotid glands can be observed during radiation therapy delivery for HNC. The mean (±SD) CTNs in GTV and ipsi- and contralateral parotid glands were reduced by 6 ± 10, 8 ± 7, and 11 ± 10 Hounsfield units, respectively, for all patients studied. The mean CTN changes in both spinal cord and nonspecified tissue were almost invisible (<2 Hounsfield units). For 2 patients studied, the absolute mean CTN changes in GTV and parotid glands were strongly correlated with the dose delivered (P<.001 and P<.05, respectively). For the correlation between CTN reductions and delivered isodose bins for parotid glands, the Pearson coefficient varied from −0.98 (P<.001) in regions with low-dose bins to 0.96 (P<.001) in high-dose bins and were patient specific. Conclusions: The CTN can be reduced in tumor and parotid glands during the course of radiation therapy for HNC. There was a fair correlation between CTN reduction and radiation doses for a subset of patients, whereas the correlation between CTN reductions and volume reductions in GTV and parotid glands were weak. More studies are needed to understand the mechanism for the radiation-induced CTN changes.

  3. Microcomputer Polling Improvements for AFSATCOM.

    Science.gov (United States)

    1981-06-01

    SBC 80/20 SINGLE BOARD COMPUTER 28 5.2 NATIONAL SEMICONDUCTOR BLC 416 16K PROM BOARD 32 5.3 INTEL 450 16K RAM BOARD 32 5.4 I/O AND DISPLAY CIRCUITS 32...Data Adapter (Sheet 6) 41 5-10 SBC 80/20 Single Board Computer Interfaces (Sheet 7) 42 5-11 Slot Counter/Display (Sheet 8) 43 5-12 RS-232 Serial...report describes a breadb6ard microcomputer system based on an Intel SBC 80/20 Single Board Computer (SBC) which fulfills the project demonstration

  4. Transthoracic Computed Tomography-Guided Lung Nodule Biopsy: Comparison of Core Needle and Fine Needle Aspiration Techniques.

    Science.gov (United States)

    Sangha, Bippan S; Hague, Cameron J; Jessup, Jennifer; O'Connor, Robert; Mayo, John R

    2016-08-01

    To determine if there is a statistically significant difference in the computed tomography (CT)-guided trans-thoracic needle biopsy diagnostic rate, complication rate, and degree of pathologist confidence in diagnosis between core needle biopsy (CNB) and fine needle aspiration biopsy (FNAB). A retrospective cohort design was used to compare the diagnostic biopsy rate, diagnostic confidence, and biopsy-related complications of pneumothorax, chest tube placement, pulmonary hemorrhage, hemoptysis, admission to hospital, and length of stay between 251 transthoracic needle biopsies obtained via CNB (126) or FNAB (125). Complication rates were assessed using imaging and clinical follow-up. Final diagnosis was confirmed via surgical pathology or clinical follow-up over a period of up to 10 years. CNB provided diagnostic samples in 91% and FNA in 80% of biopsies, which was statistically significant (P < .05). The sensitivities for CNB and FNAB were 89% (85 of 95) and 95% (84 of 88), respectively. The specificity of CNB was 100% (21 of 21) and for FNAB was 81% (2 of 11) with 2 false positives in the FNAB group. The differences in complication rate was not statistically significant for pneumothorax (50% vs 46%; determined by routine postbiopsy CT), chest tube (2% vs 4%), hemoptysis (4% vs 6%), and pulmonary hemorrhage (38% vs 47%) between FNAB and CNB, respectively. Seven patients requiring chest tube were admitted to hospital, 2 in the FNAB cohort for an average of 2.5 days and 5 in the CNB cohort for an average of 4.6 days. CNB provided more diagnostic samples with no statistical difference in complication rate. Copyright © 2016 Canadian Association of Radiologists. Published by Elsevier Inc. All rights reserved.

  5. Anatomical analysis of turgescent and semi-dry resurrection plants: the effect of sample preparation on the sample, resolution, and image quality of X-ray micro-computed tomography (μCT).

    Science.gov (United States)

    Korte, Nikola; Porembski, Stefan

    2011-04-01

    Computer tomography has been used frequently for the 3-D visualization of plant anatomical traits but sample preparation has been widely neglected. Without any preparation smaller (i.e., up to 1 × 1 cm(2) ) turgescent or semi-dry plant samples (especially leaf samples) diminish the image quality of a scan due to gradual water loss and therefore constant movement. A suitable preparation for scans of turgescent and semi-dry plant samples with a high resolution μCT (plant sample efficiently. However, water molecules and vaseline both attenuate the X-ray beam, which decreases the image quality of scans of turgescent or semi-dry plant samples. Therefore, trade-offs between the spatial resolution, sample water content, sample size, and image quality have to be considered: larger samples have to be placed further away from the X-ray tube, which leads to a lower spatial resolution; water and preparation agents attenuate the X-ray beam, causing low-quality images which may be accompanied by motion artifacts compared to a scan of a dry sample, where no preparation is necessary.

  6. Surface area and volume measurements of volcanic ash particles using micro-computed tomography (micro-CT): A comparison with scanning electron microscope (SEM) stereoscopic imaging and geometric considerations

    Science.gov (United States)

    Ersoy, Orkun; Şen, Erdal; Aydar, Erkan; Tatar, İlkan; Çelik, H. Hamdi

    2010-10-01

    Volcanic ash particles are important components of explosive eruptions, and their surface textures are the subject of intense research. Characterization of ash surfaces is crucial for understanding the physics of volcanic plumes, remote sensing measurements of ash and aerosols, interfacial processes, modelling transportation and deposition of tephra and characterizing eruptive styles. A number of different methods have been used over the years to arrive at surface area estimates. The more common methods include estimates based on geometric considerations (geometric surface area) and physisorption of gas molecules on the surface of interest (physical surface area). In this study, micro computed tomography (micro-CT), which is a non-destructive method providing three-dimensional data, enabled the measurement of surface area and volume of individual ash particles. Results were compared with the values obtained from SEM stereoscopic imaging and geometric considerations. Surface area estimates of micro-CT and SEM stereoscopic imaging are similar, with surface area/volume ratios (SA/V) of 0.0368 and 0.0467, respectively. Ash particle surface textures show a large deviation from that of simple geometric forms, and an approximation both to spheres and ellipsoids do not seem adequate for the representation of ash surface. SEM stereoscopic and/or micro-CT imaging are here suggested as good candidate techniques for the characterization of textures on macro-pore regions of ash particles.

  7. An analysis of brachytherapy with computed tomography-guided permanent implantation of Iodine-125 seeds for recurrent nonkeratin nasopharyngeal carcinoma

    Directory of Open Access Journals (Sweden)

    Shen X

    2015-05-01

    Full Text Available Xinying Shen,1,2 Yong Li,2 Yanfang Zhang,2 Jian Kong,2 Yanhao Li1 1Department of Interventional Radiology, Nanfang Hospital, Southern Medical University, Guangzhou, 2Department of Interventional Radiology, Shenzhen People’s Hospital, The Second Clinical Medical College of Jinan University, Shenzhen, People’s Republic of China Background: 125I seed implantation is a new method in treatment of nasopharyngeal carcinoma (NPC, and it is worthwhile to evaluate its feasibility. In this study, we performed brachytherapy with computed tomography (CT-guided permanent implantation of 125I seeds in the treatment of patients with the recurrence of NPC.Methods: A total 30 patients (20 male and ten female at the median age of 55 (range 25–80 years were diagnosed with recurrent nonkeratin NPC, with a total 38 lesions and a short disease-free interval (median ~11 months after primary radiotherapy alone or combined with chemotherapy. Patients received CT scan, starting from 2 months after the treatment. Follow-up was conducted for ~2–38 months to observe the local control rate and overall survival rate. We also analyzed the possible correlation between survival periods and the status of recurrent tumors.Results: The local control rates at 6, 12, 24, 30, and 36 months after the procedure of 125I seed implantation were 86.8%, 73.7%, 26.3%, 15.8%, and 5.3%, respectively. The overall 1-, 2-, and 3-year survival rates were 80.0% (24/30, 30.0% (9/30, and 6.7% (2/30, respectively, with a median survival period of 18 months (17.6±8.6 months. Interestingly, the survival periods of the patients who had primary radiotherapy with or without chemotherapy were 15.8±7.9 and 24.3±7.9 months, respectively. Kaplan–Meier survival analysis demonstrated that χ2 (log rank was 7.555, with very significant difference (P<0.01. The survival periods of patients in tumor stages I, II, III, and IV were 25.4±8.7, 19.8±9.4, 16.1±4.5, and 12.8±7.8 months, respectively, with

  8. Surface area and volume measurements of volcanic ash particles using micro-computed tomography (micro-CT): A comparison with scanning electron microscope (SEM) stereoscopic imaging and Brunauer-Emmett-Teller (BET) model

    Science.gov (United States)

    Ersoy, Orkun; Şen, Erdal; Aydar, Erkan; Tatar, Ä.°Lkan; Ćelik, H. Hamdi

    2010-05-01

    Volcanic ash particles are important components of explosive eruptions and their surface texture is the subject of intense research. Characterization of ash surfaces is crucial for understanding the physics of the volcanic plumes, remote sensing measurements of ash and aerosols, interfacial processes, modelling transportation and deposition of tephra and characterizing eruptive styles. A number of different methods have been used over the years to arrive at surface area estimates. The more common methods include estimates based on the geometric considerations (geometric surface area) and the physisorption of gas molecules on the surface of interest (physical surface area). In this study, micro computed tomography (micro-CT), a non-destructive method providing three-dimensional data enabled the measurement of surface areas and volumes of individual ash particles. Specific surface area estimates for ash particles were also obtained using nitrogen as gas adsorbent and the BET (Brunauer-Emmett-Teller) model. Results were compared with the values obtained from SEM stereoscopic imaging and geometric considerations. Surface area estimates of micro-CT and SEM stereoscopic imaging overlaps with mean specific surface area results of 0.0167 and 0.0214 m2/g, respectively. However, ash particle surface textures present quite a deviation from that of their geometric forms and approximation to sphere and ellipsoid both seemed to be inadequate for representation of real ash surfaces. The higher surface area estimate (> 0.4 m2/g) obtained from the technique based on physical sorption of gases (BET model here) was attributed to its capability for surface areas associated even with angstrom-sized pores. SEM stereoscopic and/or micro-CT imaging were suggested for characterization of textures on macro-pore regions of ash particles.

  9. The utility of positron emission tomography in the treatment planning of image-guided radiotherapy for non-small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Alexander eChi

    2014-10-01

    Full Text Available In the thorax, the extent of tumor may be more accurately defined with the addition of 18F-fluorodeoxyglucose (FDG positron emission tomography (PET to computed tomography (CT. This led to the increased utility of FDG-PET or PET/CT in the treatment planning of radiotherapy for non-small cell lung cancer (NSCLC. The inclusion of FDG-PET information in target volume delineation not only improves tumor localization, but also decreases the amount of normal tissue included in the planning target volume (PTV in selected patients. Therefore, it has a critical role in image guided radiotherapy (IGRT for NSCLC. In this review, the impact of FDG-PET on target volume delineation in radiotherapy for NSCLC, which may increase the possibility of safe dose escalation with IGRT, the commonly used methods for tumor target volume delineation FDG-PET for NSCLC, and its impact on clinical outcome will be discussed.

  10. Priori mask guided image reconstruction (p-MGIR) for ultra-low dose cone-beam computed tomography

    Science.gov (United States)

    Park, Justin C.; Zhang, Hao; Chen, Yunmei; Fan, Qiyong; Kahler, Darren L.; Liu, Chihray; Lu, Bo

    2015-11-01

    Recently, the compressed sensing (CS) based iterative reconstruction method has received attention because of its ability to reconstruct cone beam computed tomography (CBCT) images with good quality using sparsely sampled or noisy projections, thus enabling dose reduction. However, some challenges remain. In particular, there is always a tradeoff between image resolution and noise/streak artifact reduction based on the amount of regularization weighting that is applied uniformly across the CBCT volume. The purpose of this study is to develop a novel low-dose CBCT reconstruction algorithm framework called priori mask guided image reconstruction (p-MGIR) that allows reconstruction of high-quality low-dose CBCT images while preserving the image resolution. In p-MGIR, the unknown CBCT volume was mathematically modeled as a combination of two regions: (1) where anatomical structures are complex, and (2) where intensities are relatively uniform. The priori mask, which is the key concept of the p-MGIR algorithm, was defined as the matrix that distinguishes between the two separate CBCT regions where the resolution needs to be preserved and where streak or noise needs to be suppressed. We then alternately updated each part of image by solving two sub-minimization problems iteratively, where one minimization was focused on preserving the edge information of the first part while the other concentrated on the removal of noise/artifacts from the latter part. To evaluate the performance of the p-MGIR algorithm, a numerical head-and-neck phantom, a Catphan 600 physical phantom, and a clinical head-and-neck cancer case were used for analysis. The results were compared with the standard Feldkamp-Davis-Kress as well as conventional CS-based algorithms. Examination of the p-MGIR algorithm showed that high-quality low-dose CBCT images can be reconstructed without compromising the image resolution. For both phantom and the patient cases, the p-MGIR is able to achieve a clinically

  11. Parotid incidentaloma identified by combined {sup 18}F-fluorodeoxyglucose whole-body positron emission tomography and computed tomography: findings at grayscale and power Doppler ultrasonography and ultrasound-guided fine-needle aspiration biopsy or core-needle biopsy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang Kwon; Rho, Byung Hak [Keimyung University School of Medicine, Department of Radiology, Dongsan Medical Center, Daegu (Korea); Won, Kyoung Sook [Keimyung University School of Medicine, Nuclear Medicine, Dongsan Medical Center, Daegu (Korea)

    2009-09-15

    Twelve parotid incidentalomas in 10 consecutive subjects (nine with a known malignancy elsewhere and one presumptively healthy subject) identified by combined {sup 18}F-fluorodeoxyglucose whole-body positron emission tomography and computed tomography ({sup 18}F-FDG PET/CT) were investigated, with the aim of calculating maximum standardized uptake value (SUV{sub max}) of each FDG-avid focus, and identifying corresponding sonographic and pathologic findings. The results of ultrasound-guided fine-needle aspiration biopsy (FNAB) (n = 9) and core-needle biopsy (CNB) (n = 3) were Warthin tumor in 10 cases, and pleomorphic adenoma and chronic inflammation in one each. SUV{sub max} was 7.0-21.0 g/mL (average 13.7 g/mL) for Warthin tumor, 6.8 g/mL for pleomorphic adenoma, and 7.3 g/mL for chronic inflammation. Each FDG-avid focus corresponded to ovoid (n = 11) or lobulated (n = 1) hypoechoic mass on grayscale ultrasonography (US) and hypervascular mass, except one with chronic inflammation, on power Doppler (PD) US. Parotid incidentaloma identified by {sup 18}F-FDG PET/CT during workup of various malignancies elsewhere does not necessarily signify primary or metastatic malignancy, but indicates a high likelihood of benign lesions, particularly Warthin tumor. Such lesions should be evaluated thoroughly by US and ultrasound-guided FNAB or CNB if parotid disease would change the patient's treatment plan. (orig.)

  12. Optical topography guided semi-three-dimensional diffuse optical tomography for a multi-layer model of occipital cortex: a pilot methodological study

    Science.gov (United States)

    Ding, Hao; Zhang, Yao; He, Jie; Zhao, Huijuan; Gao, Feng

    2016-03-01

    In this paper, an optical topography (OT) guided diffuse optical tomography (DOT) scheme is developed for functional imaging of the occipital cortex. The method extends the previously proposed semi-three-dimensional DOT methodology to reconstruction of two-dimensional extracerebral and cerebral images using a visual cortex oriented five-layered slab geometry, and incorporate the OT localization regularization in the cerebral reconstruction to achieve enhanced quantitative accuracy and spatial resolution. We validate the methodology using simulated data and demonstrate its merits in comparison to the standalone OT and DOT.

  13. Life sciences flight experiments microcomputer

    Science.gov (United States)

    Bartram, Peter N.

    1987-01-01

    A promising microcomputer configuration for the Spacelab Life Sciences Lab. Equipment inventory consists of multiple processors. One processor's use is reserved, with additional processors dedicated to real time input and output operations. A simple form of such a configuration, with a processor board for analog to digital conversion and another processor board for digital to analog conversion, was studied. The system used digital parallel data lines between the boards, operating independently of the system bus. Good performance of individual components was demonstrated: the analog to digital converter was at over 10,000 samples per second. The combination of the data transfer between boards with the input or output functions on each board slowed performance, with a maximum throughput of 2800 to 2900 analog samples per second. Any of several techniques, such as use of the system bus for data transfer or the addition of direct memory access hardware to the processor boards, should give significantly improved performance.

  14. 275 C Downhole Microcomputer System

    Energy Technology Data Exchange (ETDEWEB)

    Chris Hutchens; Hooi Miin Soo

    2008-08-31

    An HC11 controller IC and along with serial SRAM and ROM support ICs chip set were developed to support a data acquisition and control for extreme temperature/harsh environment conditions greater than 275 C. The 68HC11 microprocessor is widely used in well logging tools for control, data acquisition, and signal processing applications and was the logical choice for a downhole controller. This extreme temperature version of the 68HC11 enables new high temperature designs and additionally allows 68HC11-based well logging tools and MWD tools to be upgraded for high temperature operation in deep gas reservoirs, The microcomputer chip consists of the microprocessor ALU, a small boot ROM, 4 kbyte data RAM, counter/timer unit, serial peripheral interface (SPI), asynchronous serial interface (SCI), and the A, B, C, and D parallel ports. The chip is code compatible with the single chip mode commercial 68HC11 except for the absence of the analog to digital converter system. To avoid mask programmed internal ROM, a boot program is used to load the microcomputer program from an external mask SPI ROM. A SPI RAM IC completes the chip set and allows data RAM to be added in 4 kbyte increments. The HC11 controller IC chip set is implemented in the Peregrine Semiconductor 0.5 micron Silicon-on-Sapphire (SOS) process using a custom high temperature cell library developed at Oklahoma State University. Yield data is presented for all, the HC11, SPI-RAM and ROM. The lessons learned in this project were extended to the successful development of two high temperature versions of the LEON3 and a companion 8 Kbyte SRAM, a 200 C version for the Navy and a 275 C version for the gas industry.

  15. 用显微CT研究不同植被恢复模式的土壤团聚体微结构特征%Characterization of soil aggregate microstructure under different revegetation types using micro-computed tomography

    Institute of Scientific and Technical Information of China (English)

    赵冬; 许明祥; 刘国彬; 张蓉蓉; 脱登峰

    2016-01-01

    为了更好了解不同植被恢复模式对土壤团聚体微结构的影响,该研究采用显微CT技术扫描3~5 mm土壤团聚体,获取了3.25μm 分辨率的二维图像,并应用数字图像处理软件对团聚体孔隙结构进行三维重建,定量研究了黄土丘陵区不同植被恢复模式下(自然草地、人工灌木和坡耕地)土壤团聚体微结构特征。结果表明,两种植被恢复模式均显著提高了土壤有机碳含量和团聚体水稳性(P100μm)、瘦长型孔隙度分别增加了20%、23%和24%,而分形维数和连通性指数欧拉特征值分别降低了2%和75%,且各指标二者间差异均显著(P100μm large pores and on the other hand decreased that of the pore size classes of natural grassland > cropland. The 3D fractal dimension and connectivity of soil aggregates showed a higher value in both revegetation types, suggesting pore system was improved after vegetation restoration. The total porosity, macro-porosity (>100μm), fraction of elongated pores, fractal dimension and pore connectivity were significantly higher in the artificial shrubland aggregates compared to the natural grassland aggregates, indicating that the soil structure of the artificial shrubland was more developed than that of the natural grassland. That may be due to a higher organic carbon content and more developed root system under the artificial shrubland. The 3D fractal dimension of soil aggregates showed a curvilinear positive correlation with total porosity, however, Euler number showed a curvilinear negative correlation with total porosity. The fractal dimension and connectivity showed a high sensitivity to the change of soil structure, and thus could be used for evaluating the soil quality during the revegetation in this region. These results from this study can help understand the soil processes and may be used to quantify the effects of management on environment. With the development of computed tomography, it

  16. Computed tomography guided navigation assisted percutaneous ablation of osteoid osteoma in a 7-year-old patient: the low dose approach

    Energy Technology Data Exchange (ETDEWEB)

    Krokidis, Miltiadis; Tappero, Carlo; Bogdanovic, Daniel; Stamm, Anna-Christina [Inselspital, Bern University Hospital, Department of Diagnostic, Interventional and Pediatric Radiology, Bern (Switzerland); Ziebarth, Kai [Inselspital, Bern University Hospital, Department of Pediatric Surgery, Bern (Switzerland)

    2017-07-15

    Osteoid osteoma (OO) is a benign tumour that can cause severe pain and functional limitation to children and young adults; the treatment of choice is image-guided ablation. Due to the very small size of the lesion, detection and accurate needle placement may be challenging. Computed tomography (CT) offers very detailed imaging of the skeleton and is the modality of choice for the detection of small OO and for ablation guidance. Nevertheless, CT-guided positioning of the ablation applicator is linked to significant radiation exposure, particularly for the paediatric population. This case describes the successful use of a novel CT-based navigation system that offers the possibility of accurate ablation with only minimal radiation exposure in a paediatric patient. (orig.)

  17. Microcomputer Instruction for the Learning Disabled.

    Science.gov (United States)

    Schiffman, Gilbert; And Others

    1982-01-01

    The advantages of using microcomputers, particularly with learning-disabled (LD) students, are pointed out; and an example of a successful program utilizing computers at the Johns Hopkins University is described. (SW)

  18. Microcomputers: "A New Era at Ramapo Catskill."

    Science.gov (United States)

    Freund, Alfred L.

    1983-01-01

    Discussion of the use of microcomputers in a cooperative public library system notes library management applications in areas of clerical work, word processing, book ordering, inventories, special collection catalogs, mailing lists, and a union list of serials. (EJS)

  19. Percutaneous computed tomography-guided biopsy of the lung: data from a hospital; Biopsia pulmonar percutanea guiada por tomografia computadorizada: dados de um hospital

    Energy Technology Data Exchange (ETDEWEB)

    Carazzai, Emilio Humberto; Rossi, Marcelo D' Andrea [Maximagem Diagnosticos por Imagem, Sao Paulo, SP (Brazil); Andreosi, Maristela [Hospital Beneficencia Portuguesa, Sao Paulo, SP (Brazil); Gonzalez, Fabio Mota; Tornin, Olger de Souza [Hospital Heliopolis, Sao Paulo, SP (Brazil)]. E-mail: olger1@uol.com.br; Gonzalez, Sandra de Quadros Uzeda [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil)

    2006-07-15

    Objective: to present the experience of Santa Cecilia Hospital (Sao Paulo, SP, Brazil) radiology service in the handling of computed tomography-guided fine-needle aspiration biopsy and percutaneous core biopsy of pulmonary lesions, analyzing their importance and associated complications. Materials and methods: one hundred and sixty-eight computed tomography-guided biopsies were performed in 84 men and 84 women. Sixty-four patients underwent fine-needle aspiration biopsy, 68 underwent percutaneous core biopsy and 36 patients underwent both techniques. Results: pneumothorax occurred in 38 patients, and pulmonary hemorrhage in then cases. The biopsied lesions ranged in size from 0.5 to 15 cm. The diagnosis was achieved at the first attempt in 132 cases and at the second attempt, in ten cases. Conclusion: the accuracy of fine-needle aspiration and percutaneous core biopsies depends both on the size of the lesion and the patient's cooperation. These techniques are relatively safe and present a high diagnostic accuracy when performed by an experienced professional. (author)

  20. Accuracy evaluation of computed tomography-derived stereolithographic surgical guides in zygomatic implant placement in human cadavers

    National Research Council Canada - National Science Library

    Chrcanovic, Bruno R; Oliveira, Davidson R; Custódio, Antônio L

    2010-01-01

    ...) and computer-aided manufacturing (CAM) techniques furnishes some advantages regarding tridimensional determination of the patient's anatomy and fabrication of both anatomic models and surgical guides...

  1. Common-mask guided image reconstruction (c-MGIR) for enhanced 4D cone-beam computed tomography

    Science.gov (United States)

    Park, Justin C.; Zhang, Hao; Chen, Yunmei; Fan, Qiyong; Li, Jonathan G.; Liu, Chihray; Lu, Bo

    2015-12-01

    Compared to 3D cone beam computed tomography (3D CBCT), the image quality of commercially available four-dimensional (4D) CBCT is severely impaired due to the insufficient amount of projection data available for each phase. Since the traditional Feldkamp-Davis-Kress (FDK)-based algorithm is infeasible for reconstructing high quality 4D CBCT images with limited projections, investigators had developed several compress-sensing (CS) based algorithms to improve image quality. The aim of this study is to develop a novel algorithm which can provide better image quality than the FDK and other CS based algorithms with limited projections. We named this algorithm ‘the common mask guided image reconstruction’ (c-MGIR). In c-MGIR, the unknown CBCT volume is mathematically modeled as a combination of phase-specific motion vectors and phase-independent static vectors. The common-mask matrix, which is the key concept behind the c-MGIR algorithm, separates the common static part across all phase images from the possible moving part in each phase image. The moving part and the static part of the volumes were then alternatively updated by solving two sub-minimization problems iteratively. As the novel mathematical transformation allows the static volume and moving volumes to be updated (during each iteration) with global projections and ‘well’ solved static volume respectively, the algorithm was able to reduce the noise and under-sampling artifact (an issue faced by other algorithms) to the maximum extent. To evaluate the performance of our proposed c-MGIR, we utilized imaging data from both numerical phantoms and a lung cancer patient. The qualities of the images reconstructed with c-MGIR were compared with (1) standard FDK algorithm, (2) conventional total variation (CTV) based algorithm, (3) prior image constrained compressed sensing (PICCS) algorithm, and (4) motion-map constrained image reconstruction (MCIR) algorithm, respectively. To improve the efficiency of the

  2. Visibility of solid and liquid fiducial markers used for image-guided radiation therapy on optical coherence tomography: an esophageal phantom study (Conference Presentation)

    Science.gov (United States)

    Jelvehgaran, Pouya; Alderliesten, Tanja; Weda, Jelmer J. A.; de Bruin, Daniel M.; Faber, Dirk J.; Hulshof, Maarten C. C. M.; van Leeuwen, Ton G.; van Herk, Marcel B.; de Boer, Johannes F.

    2017-03-01

    Radiation therapy (RT) is used in operable and inoperable esophageal cancer patients. Endoscopic ultrasound-guided fiducial marker placement allows improved translation of the disease extent on endoscopy to computed tomography (CT) images used for RT planning and enables image-guided RT. However, microscopic tumor extent at the time of RT planning is unknown. Endoscopic optical coherence tomography (OCT) is a high-resolution (10-30µm) imaging modality with the potential for accurately determining the longitudinal disease extent. Visibility of fiducial markers on OCT is crucial for integrating OCT findings with the RT planning CT. We investigated the visibility on OCT (NinePoint Medical, Inc.) of 13 commercially available solid (Visicoil, Gold Anchor, Flexicoil, Polymark, and QLRAD) and liquid (BioXmark, Lipiodol, and Hydrogel) fiducial markers of different diameter. We designed and manufactured a set of dedicated Silicone-based esophageal phantoms to perform imaging in a controlled environment. The esophageal phantoms consist of several layers with different TiO2 concentrations to simulate the scattering properties of a typical healthy human esophagus. Markers were placed at various depths (0.5, 1.1, 2.0, and 3.0mm). OCT imaging allowed detection of all fiducial markers and phantom layers. The signal to background ratio was 6-fold higher for the solid fiducial markers than the liquid fiducial markers, yet OCT was capable of visualizing all 13 fiducial markers at all investigated depths. We conclude that RT fiducial markers can be visualized with OCT. This allows integration of OCT findings with CT for image-guided RT.

  3. Evaluation of a novel Seldinger-needle for computed tomography guided interventions: initial experiences; Evaluierung einer neuen Seldinger-Nadel fuer computertomografisch gesteuerte Interventionen: Erste Erfahrungen

    Energy Technology Data Exchange (ETDEWEB)

    Plumhans, C.; Mahnken, A.; Iwa, R.; Behrendt, F.F.; Sebastian, K.; Guenther, R.W.; Honnef, D. [Universitaetsklinikum RWTH Aachen (Germany). Klinik fuer Radiologische Diagnostik

    2009-02-15

    To evaluate a new Seldinger puncture device for computed tomography-guided interventions under difficult conditions, to analyze applicability, and to investigate assets and drawbacks. From November 2007 to March 2008, we performed CT-guided interventions in 16 patients (7 women, 9 men; mean age 62 years old) using a new 20G-Seldinger needle (Sika-Med, Wiehl, Germany). This novel needle serves as a guide for many different interventional devices due to a guide wire welded on the proximal needle end. It allows continuous application of anesthesia via four tiny holes at the distal needle end until the region of interest is reached. Each intervention was subject to difficult interventional conditions. The indications for intervention were drainage (n = 7), Trucut biopsy of tumor (n = 8) and radiofrequency ablation (n = 1). Handling, success, advantages, drawbacks, complications and patient tolerance were noted after each procedure. A pain scale from 1 - 10 was used to grade the pain level during the intervention. All interventions were performed successfully and no severe complications were observed. Patient tolerance was very good resulting in a mean pain score of 2 {+-} 1. Regions with dangerous and difficult access were successfully reached with the new Seldinger needle in 15 of 16 cases by dilatation of the puncture tract and continuous administration of local anesthesia via the system. Furthermore, different devices such as Trucut systems and a drainage catheter were able to be inserted without complication via the needle. With a proximal removable luer-lock connection, liquid material was able to be aspirated in six cases. Under difficult interventional conditions, the use of a Seldinger needle as a reliable technique for CT-guided interventions can provide a safe and successful procedure. (orig.)

  4. Cone beam computed tomography guided treatment delivery and planning verification for magnetic resonance imaging only radiotherapy of the brain

    DEFF Research Database (Denmark)

    Edmund, Jens M.; Andreasen, Daniel; Mahmood, Faisal;

    2015-01-01

    Background. Radiotherapy based on MRI only (MRI-only RT) shows a promising potential for the brain. Much research focuses on creating a pseudo computed tomography (pCT) from MRI for treatment planning while little attention is often paid to the treatment delivery. Here, we investigate if cone beam...

  5. Short-term outcomes and safety of computed tomography-guided percutaneous microwave ablation of solitary adrenal metastasis from lung cancer: A multi-center retrospective study

    Energy Technology Data Exchange (ETDEWEB)

    Men, Min; Ye, Xin; Yang, Xia; Zheng, Aimin; Huang, Guang Hui; Wei, Zhigang [Dept. of Oncology, Shandong Provincial Hospital Affiliated with Shandong University, Jinan (China); Fan, Wei Jun [Imaging and Interventional Center, Sun Yat-sen University Cancer Center, Guangzhou (China); Zhang, Kaixian [Dept. of Oncology, Teng Zhou Central People' s Hospital Affiliated with Jining Medical College, Tengzhou (China); Bi, Jing Wang [Dept. of Oncology, Jinan Military General Hospital of Chinese People' s Liberation Army, Jinan (China)

    2016-11-15

    To retrospectively evaluate the short-term outcomes and safety of computed tomography (CT)-guided percutaneous microwave ablation (MWA) of solitary adrenal metastasis from lung cancer. From May 2010 to April 2014, 31 patients with unilateral adrenal metastasis from lung cancer who were treated with CT-guided percutaneous MWA were enrolled. This study was conducted with approval from local Institutional Review Board. Clinical outcomes and complications of MWA were assessed. Their tumors ranged from 1.5 to 5.4 cm in diameter. After a median follow-up period of 11.1 months, primary efficacy rate was 90.3% (28/31). Local tumor progression was detected in 7 (22.6%) of 31 cases. Their median overall survival time was 12 months. The 1-year overall survival rate was 44.3%. Median local tumor progression-free survival time was 9 months. Local tumor progression-free survival rate was 77.4%. Of 36 MWA sessions, two (5.6%) had major complications (hypertensive crisis). CT-guided percutaneous MWA may be fairly safe and effective for treating solitary adrenal metastasis from lung cancer.

  6. Short-Term Outcomes and Safety of Computed Tomography-Guided Percutaneous Microwave Ablation of Solitary Adrenal Metastasis from Lung Cancer: A Multi-Center Retrospective Study

    Science.gov (United States)

    Men, Min; Fan, Weijun; Zhang, Kaixian; Bi, Jingwang; Yang, Xia; Zheng, Aimin; Huang, Guanghui; Wei, Zhigang

    2016-01-01

    Objective To retrospectively evaluate the short-term outcomes and safety of computed tomography (CT)-guided percutaneous microwave ablation (MWA) of solitary adrenal metastasis from lung cancer. Materials and Methods From May 2010 to April 2014, 31 patients with unilateral adrenal metastasis from lung cancer who were treated with CT-guided percutaneous MWA were enrolled. This study was conducted with approval from local Institutional Review Board. Clinical outcomes and complications of MWA were assessed. Results Their tumors ranged from 1.5 to 5.4 cm in diameter. After a median follow-up period of 11.1 months, primary efficacy rate was 90.3% (28/31). Local tumor progression was detected in 7 (22.6%) of 31 cases. Their median overall survival time was 12 months. The 1-year overall survival rate was 44.3%. Median local tumor progression-free survival time was 9 months. Local tumor progression-free survival rate was 77.4%. Of 36 MWA sessions, two (5.6%) had major complications (hypertensive crisis). Conclusion CT-guided percutaneous MWA may be fairly safe and effective for treating solitary adrenal metastasis from lung cancer. PMID:27833402

  7. Enlist micros: Training science teachers to use microcomputers

    Science.gov (United States)

    Baird, William E.; Ellis, James D.; Kuerbis, Paul J.

    A National Science Foundation grant to the Biological Sciences Curriculum Study (BSCS) at The Colorado College supported the design and production of training materials to encourage literacy of science teachers in the use of microcomputers. ENLIST Micros is based on results of a national needs assessment that identified 22 compentencies needed by K-12 science teachers to use microcomputers for instruction. A writing team developed the 16-hour training program in the summer of 1985, and field-test coordinators tested it with 18 preservice or in-service groups during the 1985-86 academic year at 15 sites within the United States. The training materials consist of video programs, interactive computer disks for the Apple II series microcomputer, a training manual for participants, and a guide for the group leader. The experimental materials address major areas of educational computing: awareness, applications, implementation, evaluation, and resources. Each chapter contains activities developed for this program, such as viewing video segments of science teachers who are using computers effectively and running commercial science and training courseware. Role playing and small-group interaction help the teachers overcome their reluctance to use computers and plan for effective implementation of microcomputers in the school. This study examines the implementation of educational computing among 47 science teachers who completed the ENLIST Micros training at a southern university. We present results of formative evaluation for that site. Results indicate that both elementary and secondary teachers benefit from the training program and demonstrate gains in attitudes toward computer use. Participating teachers said that the program met its stated objectives and helped them obtain needed skills. Only 33 percent of these teachers, however, reported using computers one year after the training. In June 1986, the BSCS initiated a follow up to the ENLIST Micros curriculum to

  8. [General-purpose microcomputer for medical laboratory instruments].

    Science.gov (United States)

    Vil'ner, G A; Dudareva, I E; Kurochkin, V E; Opalev, A A; Polek, A M

    1984-01-01

    Presented in the paper is the microcomputer based on the KP580 microprocessor set. Debugging of the hardware and the software by using the unique debugging stand developed on the basis of microcomputer "Electronica-60" is discussed.

  9. Cervical Gross Tumor Volume Dose Predicts Local Control Using Magnetic Resonance Imaging/Diffusion-Weighted Imaging—Guided High-Dose-Rate and Positron Emission Tomography/Computed Tomography—Guided Intensity Modulated Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Dyk, Pawel; Jiang, Naomi; Sun, Baozhou; DeWees, Todd A. [Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States); Fowler, Kathryn J.; Narra, Vamsi [Department of Diagnostic Radiology, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Missouri (United States); Garcia-Ramirez, Jose L.; Schwarz, Julie K. [Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States); Grigsby, Perry W., E-mail: pgrigsby@wustl.edu [Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States); Division of Nuclear Medicine, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Missouri (United States); Division of Gynecologic Oncology, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Missouri (United States); Alvin J. Siteman Cancer Center, Washington University School of Medicine, St Louis, Missouri (United States)

    2014-11-15

    Purpose: Magnetic resonance imaging/diffusion weighted-imaging (MRI/DWI)-guided high-dose-rate (HDR) brachytherapy and {sup 18}F-fluorodeoxyglucose (FDG) — positron emission tomography/computed tomography (PET/CT)-guided intensity modulated radiation therapy (IMRT) for the definitive treatment of cervical cancer is a novel treatment technique. The purpose of this study was to report our analysis of dose-volume parameters predicting gross tumor volume (GTV) control. Methods and Materials: We analyzed the records of 134 patients with International Federation of Gynecology and Obstetrics stages IB1-IVB cervical cancer treated with combined MRI-guided HDR and IMRT from July 2009 to July 2011. IMRT was targeted to the metabolic tumor volume and lymph nodes by use of FDG-PET/CT simulation. The GTV for each HDR fraction was delineated by use of T2-weighted or apparent diffusion coefficient maps from diffusion-weighted sequences. The D100, D90, and Dmean delivered to the GTV from HDR and IMRT were summed to EQD2. Results: One hundred twenty-five patients received all irradiation treatment as planned, and 9 did not complete treatment. All 134 patients are included in this analysis. Treatment failure in the cervix occurred in 24 patients (18.0%). Patients with cervix failures had a lower D100, D90, and Dmean than those who did not experience failure in the cervix. The respective doses to the GTV were 41, 58, and 136 Gy for failures compared with 67, 99, and 236 Gy for those who did not experience failure (P<.001). Probit analysis estimated the minimum D100, D90, and Dmean doses required for ≥90% local control to be 69, 98, and 260 Gy (P<.001). Conclusions: Total dose delivered to the GTV from combined MRI-guided HDR and PET/CT-guided IMRT is highly correlated with local tumor control. The findings can be directly applied in the clinic for dose adaptation to maximize local control.

  10. The Surge of Micro-computers

    Science.gov (United States)

    Morita, Written By Ichiko; Matsumura, Translated By Tamiko

    Libraries in the United States are now experiencing another phase of rapid change brought by the sudden invasion of micro-computers. Their versatility has made available not only capabilities for word processing and producing spread sheets but also introduced new approaches to large research libraries’ information networks. OCLC’s microenhancers are one example of what is now available. They can be used for retrospective conversion, provide instruction for the use of and function as front end terminals for large online catalogs. Various new ideas for the application of micro-computers will bring interesting developments in library automation.

  11. Automated voxel classification used with atlas-guided diffuse optical tomography for assessment of functional brain networks in young and older adults.

    Science.gov (United States)

    Li, Lin; Cazzell, Mary; Babawale, Olajide; Liu, Hanli

    2016-10-01

    Atlas-guided diffuse optical tomography (atlas-DOT) is a computational means to image changes in cortical hemodynamic signals during human brain activities. Graph theory analysis (GTA) is a network analysis tool commonly used in functional neuroimaging to study brain networks. Atlas-DOT has not been analyzed with GTA to derive large-scale brain connectivity/networks based on near-infrared spectroscopy (NIRS) measurements. We introduced an automated voxel classification (AVC) method that facilitated the use of GTA with atlas-DOT images by grouping unequal-sized finite element voxels into anatomically meaningful regions of interest within the human brain. The overall approach included volume segmentation, AVC, and cross-correlation. To demonstrate the usefulness of AVC, we applied reproducibility analysis to resting-state functional connectivity measurements conducted from 15 young adults in a two-week period. We also quantified and compared changes in several brain network metrics between young and older adults, which were in agreement with those reported by a previous positron emission tomography study. Overall, this study demonstrated that AVC is a useful means for facilitating integration or combination of atlas-DOT with GTA and thus for quantifying NIRS-based, voxel-wise resting-state functional brain networks.

  12. Motion-compensated hand-held common-path Fourier-domain optical coherence tomography probe for image-guided intervention

    Science.gov (United States)

    Huang, Yong; Song, Cheol; Liu, Xuan; Kang, Jin U.

    2013-03-01

    A motion-compensated hand-held common-path Fourier-domain optical coherence tomography imaging probe has been developed for image guided intervention during microsurgery. A hand-held prototype instrument was designed and fabricated by integrating an imaging fiber probe inside a stainless steel needle which is attached to the ceramic shaft of a piezoelectric motor housed in an aluminum handle. The fiber probe obtains A-scan images. The distance information was extracted from the A-scans to track the sample surface distance and a fixed distance was maintained by a feedback motor control which effectively compensated hand tremor and target movements in the axial direction. Graphical user interface, real-time data processing, and visualization based on a CPU-GPU hybrid programming architecture were developed and used in the implantation of this system. To validate the system, free-hand optical coherence tomography images using various samples were obtained. The system can be easily integrated into microsurgical tools and robotics for a wide range of clinical applications. Such tools could offer physicians the freedom to easily image sites of interest with reduced risk and higher image quality.

  13. Clinical impact of computed tomography-based image-guided brachytherapy for cervix cancer using the tandem-ring applicator - the Addenbrooke's experience.

    Science.gov (United States)

    Tan, L T; Coles, C E; Hart, C; Tait, E

    2009-04-01

    We report our initial 3-year experience of chemoradiotherapy for cervical cancer with computed tomography-based image-guided high dose rate (HDR) brachytherapy using the tandem-ring applicator. Twenty-eight patients were treated between February 2005 and December 2007. All patients received initial external beam radiotherapy (EBRT) followed by HDR brachytherapy (planned dose 21 Gy to point A in three fractions over 8 days). For each insertion, a computed tomography scan was obtained with the brachytherapy applicator in situ. The cervix, uterus and organs at risk (OAR) were contoured on the computed tomography images to create an individualised dosimetry plan. The D(90) (the dose delivered to 90% of the tumour target), V(100) (the percentage of tumour target volume receiving 100% of the prescribed dose) and the minimum dose in the most exposed 2 cm(3) volume (D(2 cc)) of rectum, bladder and bowel were recorded. The equivalent dose in 2 Gy fractions delivered by EBRT and brachytherapy was calculated. The 3-year cancer-specific survival was 81%, with a pelvic control rate of 96%. In 24 patients, a D(90)>or=74 Gy (alpha/beta10) was achieved. The only patient with local recurrence had a D(90) of 63.8 Gy(alpha/beta10). The overall actuarial risk of serious late morbidity was 14%. Seventeen patients had satisfactory OAR doses using the standard loading pattern. Seven patients had modifications to reduce the risk of toxicity, whereas two had modifications to improve the tumour dose. Comparison with a previous cohort of patients treated with chemoradiotherapy and a conventionally planned low dose rate triple source brachytherapy technique showed an improvement in local pelvic control of 20% (P=0.04). The implementation of a computed tomography-based tandem-ring HDR brachytherapy technique in conjunction with individual dose adaptation has resulted in a significant improvement in local control at Addenbrooke's without increasing the risk of serious toxicity, and with little

  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. Microcomputers in Education: Why Is Earlier Better?

    Science.gov (United States)

    Cuffaro, Harriet K.

    1984-01-01

    Microcomputers are not necessarily a desirable teaching/learning tool for young children. Learning styles of the preschool child are not often compatible with computer assisted instruction techniques. An examination of the types of available programing activities and software is presented. (DF)

  16. Microcomputer Courseware: Characteristics and Design Trends.

    Science.gov (United States)

    Bialo, Ellen R.; Erickson, Lisa B.

    A total of 163 microcomputer programs evaluated by the Educational Products Information Exchange (EPIE) Institute through December 1983 were examined in order to identify strengths and weaknesses in instructional and technical design. Programs were evaluated in a variety of areas including the arts, business education, computer languages, computer…

  17. A microcomputer spreadsheet for aminoglycoside kinetics.

    Science.gov (United States)

    Kiacz, B J

    1990-05-01

    Development of an aminoglycoside monitoring program need not entail large capital expenditures for pharmacokinetic software. Microsoft's Excel spreadsheet was used to develop a single compartment, first-order kinetics template for individualized aminoglycoside dosing. The formulas employed may be adapted to virtually any other microcomputer spreadsheet package to provide accurate professional results.

  18. Microcomputer Peripheral Service Technician. Teacher Edition.

    Science.gov (United States)

    Brown, A. O., III; Fulkerson, Dan, Ed.

    This manual is the third of a three-text microcomputer service and repair series. This text is designed to assist instructors in teaching service and repair procedures for floppy disk drives, printers, and monitors. The manual contains five units. Each instructional unit includes some or all of these basic components: performance objectives,…

  19. ⁶⁴Cu-Doped PdCu@Au Tripods: A Multifunctional Nanomaterial for Positron Emission Tomography and Image-Guided Photothermal Cancer Treatment.

    Science.gov (United States)

    Pang, Bo; Zhao, Yongfeng; Luehmann, Hannah; Yang, Xuan; Detering, Lisa; You, Meng; Zhang, Chao; Zhang, Lei; Li, Zhi-Yuan; Ren, Qiushi; Liu, Yongjian; Xia, Younan

    2016-03-22

    This article reports a facile synthesis of radiolabeled PdCu@Au core-shell tripods for use in positron emission tomography (PET) and image-guided photothermal cancer treatment by directly incorporating radioactive (64)Cu atoms into the crystal lattice. The tripod had a unique morphology determined by the PdCu tripod that served as a template for the coating of Au shell, in addition to well-controlled specific activity and physical dimensions. The Au shell provided the nanostructure with strong absorption in the near-infrared region and effectively prevented the Cu and (64)Cu atoms in the core from oxidization and dissolution. When conjugated with D-Ala1-peptide T-amide (DAPTA), the core-shell tripods showed great enhancement in targeting the C-C chemokine receptor 5 (CCR5), a newly identified theranostic target up-regulated in triple negative breast cancer (TNBC). Specifically, the CCR5-targeted tripods with an arm length of about 45 nm showed 2- and 6-fold increase in tumor-to-blood and tumor-to-muscle uptake ratios, respectively, relative to their nontargeted counterpart in an orthotopic mouse 4T1 TNBC model at 24 h postinjection. The targeting specificity was further validated via a competitive receptor blocking study. We also demonstrated the use of these targeted, radioactive tripods for effective photothermal treatment in the 4T1 tumor model as guided by PET imaging. The efficacy of treatment was confirmed by the significant reduction in tumor metabolic activity revealed through the use of (18)F-fluorodeoxyglucose PET/CT imaging. Taken together, we believe that the (64)Cu-doped PdCu@Au tripods could serve as a multifunctional platform for both PET imaging and image-guided photothermal cancer therapy.

  20. Computed tomography-guided percutaneous core needle biopsy for diagnosis of mediastinal mass lesions: Experience with 110 cases in two university hospitals in Isfahan, Iran

    Science.gov (United States)

    Rabbani, Masoud; Sarrami, Amir Hossein

    2016-01-01

    Background: Computed tomography-guided percutaneous core needle biopsy (PCNB) is a diagnostic technique for initial assessment of mediastinal mass lesions. This study was conducted to evaluate its diagnostic yield and its complication rate. Materials and Methods: We reviewed the records of CT-guided PCNB in 110 patients with mediastinal mass lesions performed in Kashani and Alzahra Hospitals, Isfahan, from 2006 to 2012. Gender, age at biopsy, size, and anatomic location of the lesion, number of passes, site of approach, complications, and final diagnosis were extracted. Results: Our series encompasses 52 (47.2%) females and 58 (52/7%) males with mean age of 41 ± 8 years. The most common site of involvement was the anterior mediastinum (91.8% of cases). An average of 3/5 passes per patient has been taken for tissue sampling. Parasternal site was the most frequent approach taken for PCNB (in 78.1% of cases). Diagnostic tissue was obtained in 99 (90%) biopsies while, in 11 (10%) cases, specimen materials were inadequate. Lymphoma (49.5%) and bronchogenic carcinoma (33.3%) were the most frequent lesions in our series. The overall complication rate was 17.2% from which 10.9% was pneumothorax, 5.4% was hemoptysis, and 0.9% was vasovagal reflex. Conclusion: CT-guided PCNB is a safe and reliable procedure that can provide a precise diagnosis for patients with both benign and malignant mediastinal masses, and it is considered the preferred first diagnostic procedure use for this purpose.

  1. Establishing a Customized Guide Plate for Osteotomy in Total Knee Arthroplasty Using Lower-extremity X-ray and Knee Computed Tomography Images

    Institute of Scientific and Technical Information of China (English)

    Jin Zhang; Xiao-Bin Tian; Li Sun; Ru-Yin Hu; Jia-Liang Tian; Wei Han; Jin-Min Zhao

    2016-01-01

    Background: The conventional method cannot guarantee the precise osteotomies required for a perfect realignment and a better prognosis after total knee arthroplasty (TKA).This study investigated a customized guide plate for osteotomy placement in TKAs with the aid of the statistical shape model technique using weight-bearing lower-extremity X-rays and computed tomography (CT) images of the knee.Methods: From October 2014 to June 2015, 42 patients who underwent a TKA in Guizhou Provincial People's Hospital were divided into a guide plate group (GPG, 21 cases) and a traditional surgery group (TSG, 21 cases) using a random number table method.In the GPG group, a guide plate was designed and printed using preoperative three-dimensional measurements to plan and digitally simulate the operation.TSG cases were treated with the conventional method.Outcomes were obtained from the postoperative image examination and short-term follow-up.Results: Operative time was 49.0 ± 10.5 min for GPG, and 62.0 ± 9.7 min in TSG.The coronal femoral angle, coronal tibial angle, posterior tibial slope, and the angle between the posterior condylar osteotomy surface and the surgical transepicondylar axis were 89.2 ± 1.7°, 89.0 ± 1.1°, 6.6 ± 1.4°, and 0.9 ± 0.3° in GPG, and 86.7 ± 2.9°, 87.6 ± 2.1°, 8.9 ± 2.8°, and 1.7 ± 0.8° in TSG, respectively.The Hospital for Special Surgery scores 3 months after surgery were 83.7 ± 18.4 in GPG and 71.5 ± 15.2 in TSG.Statistically significant differences were found between GPG and TSG in all measurements.Conclusions: A customized guide plate to create an accurate osteotomy in TKAs may be created using lower-extremity X-ray and knee CT images.This allows for shorter operative times and better postoperative alignment than the traditional surgery.Application of the digital guide plate may also result in better short-term outcomes.

  2. Clinical Study of Intra-operative Computed Tomography Guided Localization with A Hook-wire System for Small Ground Glass Opacities in Minimally Invasive Resection

    Directory of Open Access Journals (Sweden)

    Xiangyang CHU

    2014-12-01

    Full Text Available Background and objective Localization of pulmonary ground glass small nodule is the technical difficulty of minimally invasive operation resection. The aim of this study is to evaluate the value of intraoperative computed tomography (CT-guided localization using a hook-wire system for small ground glass opacity (GGO in minimally invasive resection, as well as to discuss the necessity and feasibility of surgical resection of small GGOs (<10 mm through a minimally invasive approach. Methods The records of 32 patients with 41 small GGOs who underwent intraoperative CT-guided double-thorn hook wire localization prior to video-assisted thoracoscopic wedge resection from October 2009 to October 2013 were retrospectively reviewed. All patients received video-assisted thoracoscopic surgery (VATS within 10 min after wire localization. The efficacy of intraoperative localization was evaluated in terms of procedure time, VATS success rate, and associated complications of localization. Results A total of 32 patients (15 males and 17 females underwent 41 VATS resections, with 2 simultaneous nodule resections performed in 3 patients, 3 lesion resections in 1 patient, and 5 lesions in a patient. Nodule diameters ranged from 2 mm-10 mm (mean: 5 mm. The distance of lung lesions from the nearest pleural surfaces ranged within 5 mm-24 mm (mean: 12.5 mm. All resections of lesions guided by the inserted hook wires were successfully performed by VATS (100% success rate. The mean procedure time for the CT-guided hook wire localization was 8.4 min (range: 4 min-18 min. The mean procedure time for VATS was 32 min (range: 14 min-98 min. The median hospital time was 8 d (range: 5 d-14 d. Results of pathological examination revealed 28 primary lung cancers, 9 atypical adenomatous hyperplasia, and 4 nonspecific chronic inflammations. No major complication related to the intraoperative hook wire localization and VATS was noted. Conclusion Intraoperative CT-guided hook wire

  3. Computed tomography guided fine needle aspiration cytology of thoracic lesions: 10 year experience of an interventional pulmonologist

    Directory of Open Access Journals (Sweden)

    Varinder Saini

    2016-12-01

    Results: 435 patients underwent CT-guided FNAC. Age ranged from 10 to 95 years, with male preponderance. Diagnostic yield was 80.2%. Neoplastic lesions (255/435 (58.6% were most commonly diagnosed with majority (206/255 (80.8% being non-small cell lung cancer (NSCLC. This was followed by non-neoplastic lesions (94/435 (21.6% with Tuberculosis (42/94(44.7% being most common in this group. In 227/435 patients, other details like side and size of the lesion, position of patient during the procedure, depth of lesion from skin surface, number of passes undertaken and complications, if any, were also available. They were separately analyzed. Mean size of lesion was 5.7575 X 5.4173cms (maximum vertical X maximum horizontal diameter. Mean depth to which needle was inserted was 5.6663cms. Mean number of passes per patient were 1.98. Right sided lesions were more commonly sampled than left. Supine positioning was most commonly employed. Overall complication rate was 4% (9/227. Conclusions: CT-guided FNAC for thoracic lesions can serve as early diagnostic tool and guide in planning effective management strategies. [Int J Res Med Sci 2016; 4(12.000: 5185-5189

  4. Prostate cancer and abdomino-pelvic masses with {sup 99m}Tc-HDP uptake. Contribution of the single photon emission computerized tomography guided by computerized tomography (SPECT/CT); Cancer de la prostate et masses abdominopelviennes fixant le {sup 99m}Tc-HDP. Apport de la tomographie d'emission monophotonique couplee a la tomodensitometrie (TEMP-TDM)

    Energy Technology Data Exchange (ETDEWEB)

    Granier, P.; Mourad, M. [Centre Hospitalier Antoine-Gayraud, Service de Medecine Nucleaire, 11 - Carcassonne (France)

    2009-06-15

    We report the case of a 63-year-old man, investigated for staging of a prostatic cancer, diagnosed by biopsy, following a rise in the prostatic specific antigen (P.S.A.) on a systematic assessment. The interrogation before examination revealed signs of beginning right crural neuropathy. The hydroxy-methylene diphosphonate technetium 99 m-labeled ({sup 99m}Tc-H.D.P.) whole-body bone scintigraphy highlighted two extraosseous uptake images, the first of moderated intensity in the right iliac area, the second milder, in the abdominal median area. Osseous metastases were not visualized. The single photon emission computerized tomography guided by computerized tomography (SPECT/CT) identified the median abdominal mass which corresponded to a bulky aneurysm of the under renal abdominal aorta. The right iliac mass could be accurately analyzed and differentiated from the various organs of the abdomino-pelvic cavity. Its lymphatic origin was hypothesized, but the diagnosis of lymphatic metastasis of the prostatic cancer was obtained by the pathologic examination of CT scan-guided biopsy. (authors)

  5. Concept for image-guided vitreo-retinal fs-laser surgery: adaptive optics and optical coherence tomography for laser beam shaping and positioning

    Science.gov (United States)

    Matthias, Ben; Brockmann, Dorothee; Hansen, Anja; Horke, Konstanze; Knoop, Gesche; Gewohn, Timo; Zabic, Miroslav; Krüger, Alexander; Ripken, Tammo

    2015-03-01

    Fs-lasers are well established in ophthalmic surgery as high precision tools for corneal flap cutting during laser in situ keratomileusis (LASIK) and increasingly utilized for cutting the crystalline lens, e.g. in assisting cataract surgery. For addressing eye structures beyond the cornea, an intraoperative depth resolved imaging is crucial to the safety and success of the surgical procedure due to interindividual anatomical disparities. Extending the field of application even deeper to the posterior eye segment, individual eye aberrations cannot be neglected anymore and surgery with fs-laser is impaired by focus degradation. Our demonstrated concept for image-guided vitreo-retinal fs-laser surgery combines adaptive optics (AO) for spatial beam shaping and optical coherence tomography (OCT) for focus positioning guidance. The laboratory setup comprises an adaptive optics assisted 800 nm fs-laser system and is extended by a Fourier domain optical coherence tomography system. Phantom structures are targeted, which mimic tractional epiretinal membranes in front of excised porcine retina within an eye model. AO and OCT are set up to share the same scanning and focusing optics. A Hartmann-Shack sensor is employed for aberration measurement and a deformable mirror for aberration correction. By means of adaptive optics the threshold energy for laser induced optical breakdown is lowered and cutting precision is increased. 3D OCT imaging of typical ocular tissue structures is achieved with sufficient resolution and the images can be used for orientation of the fs-laser beam. We present targeted dissection of the phantom structures and its evaluation regarding retinal damage.

  6. The Effect of Experimental Variables on Industrial X-Ray Micro-Computed Sensitivity

    Science.gov (United States)

    Roth, Don J.; Rauser, Richard W.

    2014-01-01

    A study was performed on the effect of experimental variables on radiographic sensitivity (image quality) in x-ray micro-computed tomography images for a high density thin wall metallic cylinder containing micro-EDM holes. Image quality was evaluated in terms of signal-to-noise ratio, flaw detectability, and feature sharpness. The variables included: day-to-day reproducibility, current, integration time, voltage, filtering, number of frame averages, number of projection views, beam width, effective object radius, binning, orientation of sample, acquisition angle range (180deg to 360deg), and directional versus transmission tube.

  7. Guided access cavity preparation using cone-beam computed tomography and optical surface scans - an ex vivo study

    DEFF Research Database (Denmark)

    Buchgreitz, J; Buchgreitz, M; Mortensen, D

    2016-01-01

    . An apical canal preparation was created to simulate remnants of an apical root canal that acted as the target for a drill path. The test blocks were surface scanned, and merged with a CBCT scan, and a guide rail was made. A pathway for the bur was created through a metal sleeve within the guide rail...... into dentine. The distance was measured between the centres of the performed drill path and the apical target by two examiners. A maximum distance of 0.7 mm was defined based on the radius of the bur (0.6 mm) and the radius of a root canal just visible on a radiograph (0.1 mm). The t-test was used...... for evaluation, and intra- and inter-examiner reproducibility was expressed by intraclass correlation coefficients. RESULTS: The mean distance between the drill path and the target was significantly lower than 0.7 mm, and null hypothesis H0 : μ = 0.7 was rejected (CI 95%: 0.31;0.49, P

  8. Percutaneous drainage of pelvic abscesses guided by computed tomography (CT); Drenaje percutaneo de abscesos pelvicos guiados por TC

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, I.; Cespedes, M.; Lanciego, C.; Pinto, J. M.; Garcia, L. [Hospital Virgen de la Salud. Toledo (Spain)

    1999-07-01

    The percutaneous drainage of a pelvic abscess is a radiological and operational procedure that has gained great acceptance as an assistance to the antibiotic or surgical treatment. We describe our experience in draining pelvic abscesses guided by Ct, with a trans abdominal or transgluteal approach. The choice of approach is made taking into account the location of the abscess, the type of pathology, the technology available and the operators experience. We drained 27 pelvic abscesses using percutaneous procedures and a radiological guide (CT or fluoroscope CT). A follow up of the patients was carried out, collecting information on the drainage time, the amount drained, the etiology, the assistance treatment, when it was necessary, and the complications observed. 96.2% of the cases were successful (26 out of the 27 patients). The most frequent etiology corresponding to our cases were abscesses with an enteral origin, especially the appendicular ones. We consider this technique to be of great diagnostic and therapeutic value for a lot of the pelvic abscesses detected, being the technique to be chosen for patients who are high risk for surgery. (Author) 22 refs.

  9. X-ray guided three-dimensional diffuse optical tomography: in vivo study of osteoarthritis in the finger joints

    Science.gov (United States)

    Zhang, Qizhi; Yuan, Zhen; Sobel, Eric; Jiang, Huabei

    2007-02-01

    Osteoarthritis (OA), characterized by the damage of the articular cartilage, is the most common joint problem worldwide. In the effort of developing new clinical tools with the potential to alter the natural history of OA, near-infrared diffuse optical tomography (DOT) has received much attention due to its unique advantages. For optical imaging in highly heterogeneous media such as the finger joints, prior information could improve the quality of optical imaging. We report a hybrid imaging system for early detection of OA in the finger joints by imposing the geometry information obtained by X-ray on three-dimensional near-infrared DOT. X-ray tomosynthesis was employed to recover the three-dimensional structure of the two bones based on 16 X-ray projections generated with a mini C-arm system at different directions within a range of 180 degrees. The interface was carefully designed to guarantee an accurate co-registration of the optical and x-ray modalities. The prior structural information of bones was incorporated into our multi-modality imaging reconstruction algorithm to enhance the recovery of the optical properties of joint tissues. Several healthy and OA finger joints were examined. The initial clinical results showed that this hybrid imaging system had the ability to provide much enhanced image resolution and contrast than DOT alone for OA detection.

  10. Setting ventilation parameters guided by electrical impedance tomography in an animal trial of acute respiratory distress syndrome

    Science.gov (United States)

    Czaplik, Michael; Biener, Ingeborg; Leonhardt, Steffen; Rossaint, Rolf

    2014-03-01

    Since mechanical ventilation can cause harm to lung tissue it should be as protective as possible. Whereas numerous options exist to set ventilator parameters, an adequate monitoring is lacking up to date. The Electrical Impedance Tomography (EIT) provides a non-invasive visualization of ventilation which is relatively easy to apply and commercially available. Although there are a number of published measures and parameters derived from EIT, it is not clear how to use EIT to improve clinical outcome of e.g. patients suffering from acute respiratory distress syndrome (ARDS), a severe disease with a high mortality rate. On the one hand, parameters should be easy to obtain, on the other hand clinical algorithms should consider them to optimize ventilator settings. The so called Global inhomogeneity (GI) index bases on the fact that ARDS is characterized by an inhomogeneous injury pattern. By applying positive endexpiratory pressures (PEEP), homogeneity should be attained. In this study, ARDS was induced by a double hit procedure in six pigs. They were randomly assigned to either the EIT or the control group. Whereas in the control group the ARDS network table was used to set the PEEP according to the current inspiratory oxygen fraction, in the EIT group the GI index was calculated during a decremental PEEP trial. PEEP was kept when GI index was lowest. Interestingly, PEEP was significantly higher in the EIT group. Additionally, two of these animals died ahead of the schedule. Obviously, not only homogeneity of ventilation distribution matters but also limitation of over-distension.

  11. Dose measurements on cone beam computed tomography for trilogy and truebeam STx for image-guided radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Kwon; Ye, Sung Joon [Dept. of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, Seoul (Korea, Republic of); Kwon, Hyuck Jun; Sung, Won Mo [Interdisciplinary program in Radiation applied Life Science, College of Medicine, Seoul National University, Seoul (Korea, Republic of); Park, Jong Min [Dept. of Radiation Oncology, Seoul National University Hospital,Seoul (Korea, Republic of)

    2012-11-15

    The number of use of the intensity-modulated radiation therapy (IMRT) with the kV cone beam CT for the image-guided radiotherapy (IGRT) has increased. With the increased frequency in use of IGRT, the patient absorbed radiation dose during the treatment procedure has increased and become the major concern that there have been studies about these issue. The purpose of this study is to confirm the patient dose from the daily CBCT scan during the IGRT using the On-Board Imager(OBI) of Trilogy and Truebeam STx (Varian Medical Systems, CA, USA). These two linear accelerators are newly set up in SNUH that the patient dose from CBCT scan is needed to be verified before the start of IGRT. Daily CBCT scans can provide better patient localizing but increase the patient absorbed dose slightly. Considering the beneficial advantage on the localizing patient, CT dose during IGRT would be a reasonable cost.

  12. Percutaneous computed tomography-guided high-dose-rate brachytherapy ablation of breast cancer liver metastases: initial experience with 80 lesions.

    Science.gov (United States)

    Collettini, Federico; Golenia, Mascha; Schnapauff, Dirk; Poellinger, Alexander; Denecke, Timm; Wust, Peter; Riess, Hanno; Hamm, Bernd; Gebauer, Bernhard

    2012-05-01

    To analyze initial experience with computed tomography-guided high-dose-rate brachytherapy (CT-HDRBT) ablation of breast cancer liver metastases (BCLM). Between January 2008 and December 2010, 37 consecutive women with 80 liver metastases were treated with CT-HDRBT in 56 sessions. Mean age was 58.6 years (range, 34-83 y). Treatment was performed by CT-guided applicator placement and high-dose-rate brachytherapy with an iridium-192 source. The mean radiation dose was 18.57 Gy (standard deviation 2.27). Tumor response was evaluated by gadoxetic acid-enhanced liver magnetic resonance (MR) imaging performed before treatment, 6 weeks after treatment, and every 3 months thereafter. Two patients were lost to follow-up; the remaining 35 patients were available for MR imaging evaluation for a mean follow-up time of 11.6 months (range 3-32 mo). Mean tumor diameter was 25.5 mm (range 8-74 mm). Two (2.6%) local recurrences were observed after local tumor control for 10 months and 12 months. Both local progressions were successfully retreated. Distant tumor progression (new metastases or enlargement of nontreated metastases) occurred during the follow-up period in 11 (31.4%) patients. Seven (20%) patients died during the follow-up period. Overall survival ranged from 3-39 months (median 18 months). CT-HDRBT is a safe and effective ablative therapy, providing a high rate of local tumor control in patients with BCLM. Copyright © 2012 SIR. Published by Elsevier Inc. All rights reserved.

  13. Atlas-guided volumetric diffuse optical tomography enhanced by generalized linear model analysis to image risk decision-making responses in young adults.

    Science.gov (United States)

    Lin, Zi-Jing; Li, Lin; Cazzell, Mary; Liu, Hanli

    2014-08-01

    Diffuse optical tomography (DOT) is a variant of functional near infrared spectroscopy and has the capability of mapping or reconstructing three dimensional (3D) hemodynamic changes due to brain activity. Common methods used in DOT image analysis to define brain activation have limitations because the selection of activation period is relatively subjective. General linear model (GLM)-based analysis can overcome this limitation. In this study, we combine the atlas-guided 3D DOT image reconstruction with GLM-based analysis (i.e., voxel-wise GLM analysis) to investigate the brain activity that is associated with risk decision-making processes. Risk decision-making is an important cognitive process and thus is an essential topic in the field of neuroscience. The Balloon Analog Risk Task (BART) is a valid experimental model and has been commonly used to assess human risk-taking actions and tendencies while facing risks. We have used the BART paradigm with a blocked design to investigate brain activations in the prefrontal and frontal cortical areas during decision-making from 37 human participants (22 males and 15 females). Voxel-wise GLM analysis was performed after a human brain atlas template and a depth compensation algorithm were combined to form atlas-guided DOT images. In this work, we wish to demonstrate the excellence of using voxel-wise GLM analysis with DOT to image and study cognitive functions in response to risk decision-making. Results have shown significant hemodynamic changes in the dorsal lateral prefrontal cortex (DLPFC) during the active-choice mode and a different activation pattern between genders; these findings correlate well with published literature in functional magnetic resonance imaging (fMRI) and fNIRS studies.

  14. Microcomputer for controlled substance record keeping.

    Science.gov (United States)

    Stein, R L; Motta, L J; Yee, A D

    1984-01-01

    The use of a microcomputer to maintain controlled substance inventory and record keeping is described. The system maintains perpetual inventories of the central narcotic vault and proof-of-use controlled drug records outstanding at nursing stations. The computerized system has eliminated (1) the delay previously encountered in the posting of transactions from the numeric log to perpetual inventory logs and (2) the potential addition and subtraction errors inherent in a manual system. Computerizing the controlled drug record-keeping system has saved approximately 166 minutes of labor per day, a cost savings of approximately $26. The new system also helps prevent diversion of controlled substances. The computer may also be used for other tasks while not running the controlled substance program. A microcomputer is well suited to the task of controlled-substance record-keeping functions, and the cost of the system (less than $4000) can be quickly recouped in labor savings.

  15. Exchanger network synthesis on a microcomputer

    Energy Technology Data Exchange (ETDEWEB)

    Govind, R.; Mocsny, D.; Cosson, P.; Klei, J.

    1986-07-01

    Recent years have seen two occurrences that have the potential to benefit the process industries; the spread of low-cost microcomputers and the coming age of process synthesis, and the systematic approach to the creation of process flowsheets. In this paper the authors explore the two themes and outline the potential for the advancement of process synthesis with the microcomputer as an instrument of technology transfer. As an illustration, a microcomputer program that aids in the synthesis of heat exchanger networks is described. Heat exchanger network synthesis is the subproblem of process synthesis in which heat integration is performed on a partially completed flowsheet. When reactors, separators, etc., are specified, they have an associated set of streams with heating and cooling requirements. It is desirable to utilize the heating requirements of ''cold'' streams to supply the cooling requirements of the ''hot'' streams to the maximum extent possible. Heat exchanger network synthesis has the twofold aim of determining the limit on this process heat recovery and of specifying the network of exchangers that does it at the minimum investment cost. The technology is demonstrating its worth; there are reports of significant savings resulting from its application to industrial processes. The spread of this valuable technique is retarded somewhat by the shortage of experts to spearhead its implementation. The authors offer a program that can perform heat exchanger network synthesis, not as a replacement for a process designer, but as an aid for learning and a tool for the solution of design problems. The fact that it runs on the most widely accepted microcomputer means that it is accessible to any interested engineer.

  16. Challenge in Numerical Software for Microcomputers

    Energy Technology Data Exchange (ETDEWEB)

    Cody, W J

    1977-09-02

    Microcomputers are now capable of serious numerical computation using programmed floating-point arithmetic and Basic compilers. Unless numerical software designers for these machines exploit experience gained in providing software for larger machines, history will repeat with the initial spread of treacherous software. This paper discusses good software, especially for the elementary functions, in terms of reliability and robustness. The emphasis. is on insight rather than detailed algorithms, to show why certain things are important and how they may be achieved.

  17. Electrical impedance tomography-guided prone positioning in a patient with acute cor pulmonale associated with severe acute respiratory distress syndrome.

    Science.gov (United States)

    Kotani, Toru; Tanabe, Hitoshi; Yusa, Hiroaki; Saito, Satoshi; Yamazaki, Kenji; Ozaki, Makoto

    2016-02-01

    Electrical impedance tomography (EIT) is a noninvasive technique used to assess regional gas distribution in the lung. We experienced a patient with acute cor pulmonale during high positive-pressure ventilation for the treatment of severe acute respiratory distress syndrome. Prone positioning was beneficial for unloading the right ventricle for treatment of acute cor pulmonale. EIT played a role in detecting lung derecruitment at the patient's bedside. Impedance distribution in ventral, mid-ventral, mid-dorsal, and dorsal layers before and 20 min after the start of prone positioning was 9, 48, 44, and 0 %, and 10, 25, 48, and 16 %, respectively. Lung recruitment monitored by EIT paralleled the improvement of PaO2/FIO2 from 123 to 239 mmHg. Timing of termination of prone positioning and ventilator settings such as lowering positive end-expiration pressure was determined to maintain dorsal recruitment as seen by EIT. The patient was weaned from mechanical ventilation on day 32 and discharged on day 200. EIT assessed the effects of prone positioning with real-time dynamic imaging and guided less injurious mechanical ventilation in a patient with acute cor pulmonale with dorsal lung derecruitment.

  18. PET-Guided Surgery - High Correlation between Positron Emission Tomography with 11C-5-Hydroxytryptophane (5-HTP) and Surgical Findings in Abdominal Neuroendocrine Tumours.

    Science.gov (United States)

    Orlefors, Håkan; Sundin, Anders; Eriksson, Barbro; Skogseid, Britt; Oberg, Kjell; Akerström, Göran; Hellman, Per

    2012-02-08

    Positron emission tomography (PET) with 11C-labeled 5-hydroxytryptophane (5-HTP) is a sensitive technique to visualize neuroendocrine tumours (NETs), due to high intracellular uptake of amine-precursors like L-dihydroxyphenylalanine (L-DOPA) and 5-HTP. NETs are often small and difficult to localize in spite of overt clinical symptoms due to hormonal excess. In our study, 38 consecutive NET patients underwent 11C-5-HTP-PET and morphological imaging by CT within 12 weeks prior to surgery. Surgical, histopathological and 5-HTP PET findings were correlated. 11C-5-HTP-PET corresponded to the surgical findings in 31 cases, was false negative in six, and true negative in one case resulting in 83.8% sensitivity and 100% specificity. Positive predicted value was 100%. In 11 patients 11C-5-HTP-PET was the only imaging method applied to localize the tumour. Thus, we could demonstrate that functional imaging by 11C-5-HTP-PET in many cases adds vital preoperative diagnostic information and in more than every fourth patient was the only imaging method that will guide the surgeon in finding the NET-lesion. Although the present results demonstrates that 11C-5-HTP may be used as an universal NET tracer, the sensitivity to visualize benign insulinomas and non functioning pancreatic NETs was lower.

  19. PET-Guided Surgery — High Correlation between Positron Emission Tomography with 11C-5-Hydroxytryptophane (5-HTP) and Surgical Findings in Abdominal Neuroendocrine Tumours

    Science.gov (United States)

    Örlefors, Håkan; Sundin, Anders; Eriksson, Barbro; Skogseid, Britt; Öberg, Kjell; Åkerström, Göran; Hellman, Per

    2012-01-01

    Positron emission tomography (PET) with 11C-labeled 5-hydroxytryptophane (5-HTP) is a sensitive technique to visualize neuroendocrine tumours (NETs), due to high intracellular uptake of amine-precursors like L-dihydroxyphenylalanine (L-DOPA) and 5-HTP. NETs are often small and difficult to localize in spite of overt clinical symptoms due to hormonal excess. In our study, 38 consecutive NET patients underwent 11C-5-HTP-PET and morphological imaging by CT within 12 weeks prior to surgery. Surgical, histopathological and 5-HTP PET findings were correlated. 11C-5-HTP-PET corresponded to the surgical findings in 31 cases, was false negative in six, and true negative in one case resulting in 83.8% sensitivity and 100% specificity. Positive predicted value was 100%. In 11 patients 11C-5-HTP-PET was the only imaging method applied to localize the tumour. Thus, we could demonstrate that functional imaging by 11C-5-HTP-PET in many cases adds vital preoperative diagnostic information and in more than every fourth patient was the only imaging method that will guide the surgeon in finding the NET-lesion. Although the present results demonstrates that 11C-5-HTP may be used as an universal NET tracer, the sensitivity to visualize benign insulinomas and non functioning pancreatic NETs was lower. PMID:24213229

  20. Recommendations for high-risk clinical target volume definition with computed tomography for three-dimensional image-guided brachytherapy in cervical cancer patients.

    Science.gov (United States)

    Ohno, Tatsuya; Wakatsuki, Masaru; Toita, Takafumi; Kaneyasu, Yuko; Yoshida, Ken; Kato, Shingo; Li, Noriko; Tokumaru, Sunao; Ikushima, Hitoshi; Uno, Takashi; Noda, Shin-Ei; Kazumoto, Tomoko; Harima, Yoko

    2016-11-10

    Our purpose was to develop recommendations for contouring the computed tomography (CT)-based high-risk clinical target volume (CTVHR) for 3D image-guided brachytherapy (3D-IGBT) for cervical cancer. A 15-member Japanese Radiation Oncology Study Group (JROSG) committee with expertise in gynecological radiation oncology initiated guideline development for CT-based CTVHR (based on a comprehensive literature review as well as clinical experience) in July 2014. Extensive discussions occurred during four face-to-face meetings and frequent email communication until a consensus was reached. The CT-based CTVHR boundaries were defined by each anatomical plane (cranial-caudal, lateral, or anterior-posterior) with or without tumor progression beyond the uterine cervix at diagnosis. Since the availability of magnetic resonance imaging (MRI) with applicator insertion for 3D planning is currently limited, T2-weighted MRI obtained at diagnosis and just before brachytherapy without applicator insertion was used as a reference for accurately estimating the tumor size and topography. Furthermore, utilizing information from clinical examinations performed both at diagnosis and brachytherapy is strongly recommended. In conclusion, these recommendations will serve as a brachytherapy protocol to be used at institutions with limited availability of MRI for 3D treatment planning.

  1. Ultrasound-guided diffuse optical tomography (DOT) of invasive breast carcinoma: Does tumour total haemoglobin concentration contribute to the prediction of axillary lymph node status?

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Qingli, E-mail: qinglizhu@gmail.com [Department of Diagnostic Ultrasound, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan 1, Dongcheng District, Beijing 100730 (China); Xiao, Mengsu, E-mail: xiaomengsu_2000@sina.com [Department of Diagnostic Ultrasound, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan 1, Dongcheng District, Beijing 100730 (China); You, Shanshan, E-mail: shanshan_0531@sina.com [Department of Diagnostic Ultrasound, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan 1, Dongcheng District, Beijing 100730 (China); Zhang, Jing, E-mail: zhang.jing1029@163.com [Department of Diagnostic Ultrasound, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan 1, Dongcheng District, Beijing 100730 (China); Jiang, Yuxin, E-mail: yuxinjiangxh@yahoo.com.cn [Department of Diagnostic Ultrasound, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan 1, Dongcheng District, Beijing 100730 (China); Lai, Xingjian, E-mail: lxjpumch@yahoo.com.cn [Department of Diagnostic Ultrasound, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan 1, Dongcheng District, Beijing 100730 (China); Dai, Qing, E-mail: qingdai_2000@yahoo.com [Department of Diagnostic Ultrasound, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan 1, Dongcheng District, Beijing 100730 (China)

    2012-11-15

    Objectives: To prospectively study the ultrasound-guided near-infrared diffuse optical tomography (DOT) findings of the total haemoglobin concentration (THC) detected in invasive breast carcinomas and its contribution to the prediction of axillary lymph node (LN) status. Methods: A total of 195 invasive breast carcinomas were prospectively studied with DOT before surgery. Lumpectomy or mastectomy with full axillary nodal dissection was performed. Tumour size and THC level were correlated with LN status by a logistic regression analysis. Results: One hundred twenty-four patients (63.59%) was LN(-) and 71 (36.41%) was LN(+). The average THC was significantly higher in the LN(+) group than in the LN(-) group (252.94 {+-} 69.19 {mu}mol/L versus 203.86 {+-} 83.13 {mu}mol/L, P = 0.01). A multivariate analysis showed an independent relationship between the probability of axillary metastasis, elevated THC level (P = 0.01), and tumour size (P = 0.001). The odds ratio with THC {>=} 140 {mu}mol/L was 13.651 (1.781-104.560), whereas that of tumour size with a 1 cm increment was only 1.777 (1.283-2.246). Conclusions: The THC level and the tumour size are independent and preoperative predictors of axillary nodal status; these variables may improve the diagnosis of patients with lymph node metastasis.

  2. PET-Guided Surgery — High Correlation between Positron Emission Tomography with 11C-5-Hydroxytryptophane (5-HTP and Surgical Findings in Abdominal Neuroendocrine Tumours

    Directory of Open Access Journals (Sweden)

    Barbro Eriksson

    2012-02-01

    Full Text Available Positron emission tomography (PET with 11C-labeled 5-hydroxytryptophane (5-HTP is a sensitive technique to visualize neuroendocrine tumours (NETs, due to high intracellular uptake of amine-precursors like L-dihydroxyphenylalanine (L-DOPA and 5-HTP. NETs are often small and difficult to localize in spite of overt clinical symptoms due to hormonal excess. In our study, 38 consecutive NET patients underwent 11C-5-HTP-PET and morphological imaging by CT within 12 weeks prior to surgery. Surgical, histopathological and 5-HTP PET findings were correlated. 11C-5-HTP-PET corresponded to the surgical findings in 31 cases, was false negative in six, and true negative in one case resulting in 83.8% sensitivity and 100% specificity. Positive predicted value was 100%. In 11 patients 11C-5-HTP-PET was the only imaging method applied to localize the tumour. Thus, we could demonstrate that functional imaging by 11C-5-HTP-PET in many cases adds vital preoperative diagnostic information and in more than every fourth patient was the only imaging method that will guide the surgeon in finding the NET-lesion. Although the present results demonstrates that 11C-5-HTP may be used as an universal NET tracer, the sensitivity to visualize benign insulinomas and non functioning pancreatic NETs was lower.

  3. Comparative Investigation of Guided Fuzzy Clustering and Mean Shift Clustering for Edge Detection in Electrical Resistivity Tomography Images of Mineral Deposits

    Science.gov (United States)

    Ward, Wil; Wilkinson, Paul; Chambers, Jon; Bai, Li

    2014-05-01

    Geophysical surveying using electrical resistivity tomography (ERT) can be used as a rapid non-intrusive method to investigate mineral deposits [1]. One of the key challenges with this approach is to find a robust automated method to assess and characterise deposits on the basis of an ERT image. Recent research applying edge detection techniques has yielded a framework that can successfully locate geological interfaces in ERT images using a minimal assumption data clustering technique, the guided fuzzy clustering method (gfcm) [2]. Non-parametric clustering techniques are statistically grounded methods of image segmentation that do not require any assumptions about the distribution of data under investigation. This study is a comparison of two such methods to assess geological structure based on the resistivity images. In addition to gfcm, a method called mean-shift clustering [3] is investigated with comparisons directed at accuracy, computational expense, and degree of user interaction. Neither approach requires the number of clusters as input (a common parameter and often impractical), rather they are based on a similar theory that data can be clustered based on peaks in the probability density function (pdf) of the data. Each local maximum in these functions represents the modal value of a particular population corresponding to a cluster and as such the data are assigned based on their relationships to these model values. The two methods differ in that gfcm approximates the pdf using kernel density estimation and identifies population means, assigning cluster membership probabilities to each resistivity value in the model based on its distance from the distribution averages. Whereas, in mean-shift clustering, the density function is not calculated, but a gradient ascent method creates a vector that leads each datum towards high density distributions iteratively using weighted kernels to calculate locally dense regions. The only parameter needed in both methods

  4. Microcomputer Boring and Subsurface Data Package: User’s Guide.

    Science.gov (United States)

    1985-09-01

    find &bornum STORE SID TO BORSIDM STORE STR(BORSIDN,5,0) TO BORSIDC j STORE TOPiHOLE TO TOPELN store proj:name to projm store site:name to sitem STORE...LASTEL2 .AND. LINEL BOTEL2 * 0O WHILE INDX2 = 1 * @ LINE, COL2+3 SAY ’EL=’ @ LTNE, COL2+7 SAY BOTEL2 USING �.99’ j STORE INDX2+1 TO INDX2 END DO * ENDIF

  5. Microcomputer Selection Guide for Construction Field Offices. Revision.

    Science.gov (United States)

    1984-09-01

    Address: North America Mica, Inc. Suite 240 11772 Sorrento Valley Rd. San Diego , CA 92121 Telephone: 714/481-6998 Operating System: CP/M-80, CP/M-86, MS...Survivability Section, CCB-OPS ATTN: Library (14) Infrastructure Branch, LANDA US Army Europe HQ USSUCON 09128 AEAZN-ODCS/Engr 09403 ArN: ICJ 4/7-LE

  6. Computed tomography (CT)-guided interstitial permanent implantation of (125)I seeds for refractory chest wall metastasis or recurrence.

    Science.gov (United States)

    Jiang, Ping; Liu, Chen; Wang, Junjie; Yang, Ruijie; Jiang, Yuliang; Tian, Suqing

    2015-02-01

    To evaluate the efficacy and safety of 125I seeds implantation for refractory chest wall (CW) metastasis or recurrence under CT guidance. In addition we assessed initial data obtained on the therapeutic response for refractory CW metastasis or recurrence. Twenty consecutive patients underwent permanent implantation of 125I seeds (from Jul. 2004 to Jan. 2011) under computed tomography (CT) guidance. Postoperative dosimetry was routinely performed for all patients. The actuarial D90 of the implanted 125I seeds ranged from 100 Gy to 160 Gy (median: 130 Gy). The activity of 125I seeds ranged from 0.5 mCi to 0.78 mCi (median: 0.71 mCi). The total number of seeds implanted ranged from 8 to 269 (median: 53). The follow-up period ranged from 3 to 54 months (median: 11.5 months). The survival and local control probabilities were calculated by the Kaplan-Meier method. Among all the 20 patients, 3 patients had complete remission CR (15%), 12 patients had partial remission PR (60%), 5 patients had stable disease SD. The 1-, 2-, 3- and 4-year tumor control rates were all 88.7% respectively. The 1- and 2-, 3-, 4-year cancer specific survival rates were 56.5% and 47.1%, 47.1%, 47.1% respectively. The 1- and 2-, 3-, 4-year overall survival rates were 53.3% and 35.6%, 35.6%, 35.6% respectively, with a median survival of 15 months (95% CI, 7.0-22.9). Mild brachial plexus injury was seen in one patient; grade 1 or 2 skin reactions were seen in 6 patients (30%) who had received external beam radiation therapy (EBRT) before. No grade 3 and 4 skin side effects were found. Rib fracture, ulceration, pneumothorax or hemopneumothorax were not seen. Interstitial permanent implantation of 125I seeds under CT guidance is feasible, efficacious and safe for refractory CW metastasis or recurrence.

  7. Dosimetric and radiobiological consequences of computed tomography-guided adaptive strategies for intensity modulated radiation therapy of the prostate.

    Science.gov (United States)

    Battista, Jerry J; Johnson, Carol; Turnbull, David; Kempe, Jeff; Bzdusek, Karl; Van Dyk, Jacob; Bauman, Glenn

    2013-12-01

    To examine a range of scenarios for image-guided adaptive radiation therapy of prostate cancer, including different schedules for megavoltage CT imaging, patient repositioning, and dose replanning. We simulated multifraction dose distributions with deformable registration using 35 sets of megavoltage CT scans of 13 patients. We computed cumulative dose-volume histograms, from which tumor control probabilities and normal tissue complication probabilities (NTCPs) for rectum were calculated. Five-field intensity modulated radiation therapy (IMRT) with 18-MV x-rays was planned to achieve an isocentric dose of 76 Gy to the clinical target volume (CTV). The differences between D95, tumor control probability, V70Gy, and NTCP for rectum, for accumulated versus planned dose distributions, were compared for different target volume sizes, margins, and adaptive strategies. The CTV D95 for IMRT treatment plans, averaged over 13 patients, was 75.2 Gy. Using the largest CTV margins (10/7 mm), the D95 values accumulated over 35 fractions were within 2% of the planned value, regardless of the adaptive strategy used. For tighter margins (5 mm), the average D95 values dropped to approximately 73.0 Gy even with frequent repositioning, and daily replanning was necessary to correct this deficit. When personalized margins were applied to an adaptive CTV derived from the first 6 treatment fractions using the STAPLE (Simultaneous Truth and Performance Level Estimation) algorithm, target coverage could be maintained using a single replan 1 week into therapy. For all approaches, normal tissue parameters (rectum V(70Gy) and NTCP) remained within acceptable limits. The frequency of adaptive interventions depends on the size of the CTV combined with target margins used during IMRT optimization. The application of adaptive target margins (adaptive CTV determined 1 week into therapy minimizes the need for subsequent dose replanning. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Genetic algorithms-based inversion of multimode guided waves for cortical bone characterization

    Science.gov (United States)

    Bochud, N.; Vallet, Q.; Bala, Y.; Follet, H.; Minonzio, J.-G.; Laugier, P.

    2016-10-01

    Recent progress in quantitative ultrasound has exploited the multimode waveguide response of long bones. Measurements of the guided modes, along with suitable waveguide modeling, have the potential to infer strength-related factors such as stiffness (mainly determined by cortical porosity) and cortical thickness. However, the development of such model-based approaches is challenging, in particular because of the multiparametric nature of the inverse problem. Current estimation methods in the bone field rely on a number of assumptions for pairing the incomplete experimental data with the theoretical guided modes (e.g. semi-automatic selection and classification of the data). The availability of an alternative inversion scheme that is user-independent is highly desirable. Thus, this paper introduces an efficient inversion method based on genetic algorithms using multimode guided waves, in which the mode-order is kept blind. Prior to its evaluation on bone, our proposal is validated using laboratory-controlled measurements on isotropic plates and bone-mimicking phantoms. The results show that the model parameters (i.e. cortical thickness and porosity) estimated from measurements on a few ex vivo human radii are in good agreement with the reference values derived from x-ray micro-computed tomography. Further, the cortical thickness estimated from in vivo measurements at the third from the distal end of the radius is in good agreement with the values delivered by site-matched high-resolution x-ray peripheral computed tomography.

  9. Applications of Local Area Networks of Microcomputers in Libraries.

    Science.gov (United States)

    Levert, Virginia M.

    1985-01-01

    Important features of local area networks (LAN) are reviewed, and several microcomputer LANs are described (ARCnet, Hinet, ShareNet, Ethernet, Omninet, PLAN 4000). Results of survey of 10 libraries using or planning to use a microcomputer LAN and considerations in choosing a LAN are reported. Forty-one references are cited. (EJS)

  10. Profile of Change in Education: A High School Uses Microcomputers.

    Science.gov (United States)

    Grossnickle, Donald R.; Laird, Bruce A.

    1981-01-01

    This report on the introduction of microcomputers into a secondary school in a Chicago suburb briefly describes the setting for change and discusses the history of computers in the school, the emergence of change agents, microcomputer hardware selection, inservice teacher training, and the current status of the project. (MER)

  11. Handbook and Annotated Software Bibliography. Microcomputers in ABE.

    Science.gov (United States)

    Holter, Mary Patricia; Johnson, Carmen

    This handbook and annotated bibliography presents discussions, ideas, and resources useful to adult basic education (ABE) program teachers and administrators in implementing educational microcomputing, and describes microcomputer software programs that have been used successfully in ABE. The first part of the book, the handbook, is organized in…

  12. Playing the American Revolution: A Historical Microcomputer Simulation.

    Science.gov (United States)

    Sargent, James E.; Hueston, Stephen P.

    1988-01-01

    Explanation of the purpose of microcomputer simulations in history classes at the college or secondary school level focuses on the development of one simulation, The American Revolution. Highlights include effects on learning processes of using simulations in a microcomputer laboratory; student evaluations of the simulation; and creation of the…

  13. Use of Microcomputers for School Hearing Screening and Evaluation Records.

    Science.gov (United States)

    Jackson, Coleen O'Rourke

    A pilot project evaluated the use of a microcomputer database system to maintain hearing screening, evaluation, and followup records in a school for physically, emotionally, or educationally handicapped children (6 months-18 years). Using a universal database management system for a microcomputer, a program was designed which would allow for easy…

  14. Evolution of microcomputer-based medical instrumentation.

    Science.gov (United States)

    Tompkins, Willis J

    2009-01-01

    This paper provides a historical review of the evolution of the technologies that led to modern microcomputer-based medical instrumentation. I review the history of the microprocessor-based system because of the importance of the microprocessor in the design of modern medical instruments. I then give some examples of medical instruments in which the microprocessor has played a key role and in some cases has even empowered us to develop new instruments that were not possible before. I include a discussion of the role of the microprocessor-based personal computer in development of medical instruments.

  15. Feasibility of patient dose reduction based on various noise suppression filters for cone-beam computed tomography in an image-guided patient positioning system

    Science.gov (United States)

    Kamezawa, Hidemi; Arimura, Hidetaka; Shirieda, Katsutoshi; Kameda, Noboru; Ohki, Masafumi

    2016-05-01

    We investigated the feasibility of patient dose reduction based on six noise suppression filters for cone-beam computed tomography (CBCT) in an image-guided patient positioning (IGPP) system. A midpoint dose was employed as a patient dose index. First, a reference dose (RD) and low-dose (LD)-CBCT images were acquired with a reference dose and various low doses. Second, an automated rigid registration was performed for three axis translations to estimate patient setup errors between a planning CT image and the LD-CBCT images processed by six noise suppression filters (averaging filter, median filter, Gaussian filter, edge-preserving smoothing filter, bilateral filter, and adaptive partial median filter (AMF)). Third, residual errors representing the patient positioning accuracy were calculated as Euclidean distances between the setup error vectors estimated using the LD-CBCT and RD-CBCT images. Finally, the residual errors as a function of the patient dose index were estimated for LD-CBCT images processed by six noise suppression filters, and then the patient dose indices for the filtered LD-CBCT images were obtained at the same residual error as the RD-CBCT image. This approach was applied to an anthropomorphic phantom and four cancer patients. The patient dose for the LD-CBCT images was reduced to 19% of that for the RD-CBCT image for the phantom by using AMF, while keeping a same residual error of 0.47 mm as the RD-CBCT image by applying the noise suppression filters to the LD-CBCT images. The average patient dose was reduced to 31.1% for prostate cancer patients, and it was reduced to 82.5% for a lung cancer patient by applying the AMF. These preliminary results suggested that the proposed approach based on noise suppression filters could decrease the patient dose in IGPP systems.

  16. Image-guided feedback for ophthalmic microsurgery using multimodal intraoperative swept-source spectrally encoded scanning laser ophthalmoscopy and optical coherence tomography

    Science.gov (United States)

    Li, Jianwei D.; Malone, Joseph D.; El-Haddad, Mohamed T.; Arquitola, Amber M.; Joos, Karen M.; Patel, Shriji N.; Tao, Yuankai K.

    2017-02-01

    Surgical interventions for ocular diseases involve manipulations of semi-transparent structures in the eye, but limited visualization of these tissue layers remains a critical barrier to developing novel surgical techniques and improving clinical outcomes. We addressed limitations in image-guided ophthalmic microsurgery by using microscope-integrated multimodal intraoperative swept-source spectrally encoded scanning laser ophthalmoscopy and optical coherence tomography (iSS-SESLO-OCT). We previously demonstrated in vivo human ophthalmic imaging using SS-SESLO-OCT, which enabled simultaneous acquisition of en face SESLO images with every OCT cross-section. Here, we integrated our new 400 kHz iSS-SESLO-OCT, which used a buffered Axsun 1060 nm swept-source, with a surgical microscope and TrueVision stereoscopic viewing system to provide image-based feedback. In vivo human imaging performance was demonstrated on a healthy volunteer, and simulated surgical maneuvers were performed in ex vivo porcine eyes. Denselysampled static volumes and volumes subsampled at 10 volumes-per-second were used to visualize tissue deformations and surgical dynamics during corneal sweeps, compressions, and dissections, and retinal sweeps, compressions, and elevations. En face SESLO images enabled orientation and co-registration with the widefield surgical microscope view while OCT imaging enabled depth-resolved visualization of surgical instrument positions relative to anatomic structures-of-interest. TrueVision heads-up display allowed for side-by-side viewing of the surgical field with SESLO and OCT previews for real-time feedback, and we demonstrated novel integrated segmentation overlays for augmented-reality surgical guidance. Integration of these complementary imaging modalities may benefit surgical outcomes by enabling real-time intraoperative visualization of surgical plans, instrument positions, tissue deformations, and image-based surrogate biomarkers correlated with completion of

  17. Information survey for microcomputer systems integration

    Energy Technology Data Exchange (ETDEWEB)

    Hake, K.A.

    1991-12-01

    One goal of the PM-AIM is to provide US Army Project Managers (PMs) and Project Executive Officers (PEOs) with a fundamental microcomputing resource to help perform acquisition information management and its concomitant reporting requirements. Providing key application software represents one means of accomplishing this goal. This workstation would furnish a broad range of capabilities needed in the PM and PEO office settings as well as software tools for specific project management and acquisition information. Although still in the conceptual phase, the practical result of this exercise in systems integration will likely be a system called the Project Manager`s Information System (PMIS) or the AIM workstation. It would include such software as, Project Manager`s System Software (PMSS), Defense Acquisition Executive Summary (DAES), and Consolidated Acquisition Reporting System (CARS) and would conform to open systems architecture as accepted by the Department of Defense. ORNL has assisted PM-AIM in the development of technology ideas for the PMIS workstation concept. This paper represents the compilation of information gained during this process. This information is presented as a body of knowledge (or knowledge domain) defining the complex technology of microcomputing. The concept of systems integration or tying together all hardware and software components reflects the nature of PM-AIM`s task in attempting to field a PMIS or AIM workstation.

  18. Information survey for microcomputer systems integration

    Energy Technology Data Exchange (ETDEWEB)

    Hake, K.A.

    1991-12-01

    One goal of the PM-AIM is to provide US Army Project Managers (PMs) and Project Executive Officers (PEOs) with a fundamental microcomputing resource to help perform acquisition information management and its concomitant reporting requirements. Providing key application software represents one means of accomplishing this goal. This workstation would furnish a broad range of capabilities needed in the PM and PEO office settings as well as software tools for specific project management and acquisition information. Although still in the conceptual phase, the practical result of this exercise in systems integration will likely be a system called the Project Manager's Information System (PMIS) or the AIM workstation. It would include such software as, Project Manager's System Software (PMSS), Defense Acquisition Executive Summary (DAES), and Consolidated Acquisition Reporting System (CARS) and would conform to open systems architecture as accepted by the Department of Defense. ORNL has assisted PM-AIM in the development of technology ideas for the PMIS workstation concept. This paper represents the compilation of information gained during this process. This information is presented as a body of knowledge (or knowledge domain) defining the complex technology of microcomputing. The concept of systems integration or tying together all hardware and software components reflects the nature of PM-AIM's task in attempting to field a PMIS or AIM workstation.

  19. An Analysis of the Theoretical Foundations for the Use of Microcomputers in Early Childhood Education.

    Science.gov (United States)

    Streibel, Michael J.

    This discussion first analyzes major claims of a cognitive-developmentalist perspective on the use of microcomputers in early childhood education. Five topics are specifically addressed: microcomputers and intellectual structures, microcomputers as cultural events, microcomputers and strategy repetoires, instruction and the self-construction of…

  20. Efficacy and Potential MicroRNA Mechanism for Computed Tomography-Guided Percutaneous Radiofrequency Ablation of Primary Lung Cancer and Lung Metastasis from Liver Cancer

    Directory of Open Access Journals (Sweden)

    Xun Hu

    2014-04-01

    Full Text Available Background: The aim of this study was to evaluate comparatively the effectiveness of computed tomography-guided percutaneous radiofrequency ablation (CT-PRFA for primary non-small cell lung cancer (NSCLC and lung metastases from hepatocellular carcinoma (HCC and to explore the potential miRNA mechanisms for the efficacy of CT-PRFA. Methods: 14 patients pathologically diagnosed with NSCLC and 12 patients with lung metastases from HCC were enrolled in the study and underwent CT-PRFA. Clinical outcomes were compiled on the basis of review of medical records, imaging follow-up reports, and any biopsy-proved residual or recurrent disease. Real-time RT-PCR was used to quantify the selected miRNAs known to be play key roles in lung cancer. Results: A total of 21 tumors were treated with umbrella-tip electrodes and spiral-tip electrodes were used for the remaining 8 tumors. The median follow-up was 13.5 months (range, 3-30 months and no patient was lost to follow-up. The rate of technique efficacy for primary tumors was ∼93% (13 of 14. Treatment was successful in 11 out of 12 (91.7% lung metastases patients. Overall survival rate was 80.8% at 2 years, and cancer-specific survival rate was 100% at 2 years. The tumor-free survival was 69.2% at 1 year and 26.9% at 2 years. Before PRFA, tumor suppressor let-7a and miR-34a were downregulated whereas oncomiR miR-21 was upregulated in primary tumors, and let-7a and miR-126 levels were downregulated whereas oncomiRs miR-21, miR-155 and miR-17-5p/miR-20b levels were upregulated in secondary tumors. This abnormal expression was normalized by CT-PRFA. Most notably, CT-PRFA failed to normalize the deregulated miRNAs in the non-survivors. Conclusions: CT-PRFA is a effective treatment for primary NSCLCs and secondary lung tumors from HCC and the efficacy may be related to its ability to normalize deregulated expression of miRNAs: upregulating tumor suppressor miRNAs and downregulating oncomiRs.

  1. Microcomputer array processor system. [design for electronic warfare

    Science.gov (United States)

    Slezak, K. D.

    1980-01-01

    The microcomputer array system is discussed with specific attention given to its electronic warware applications. Several aspects of the system architecture are described as well as some of its distinctive characteristics.

  2. Microcomputer-controlled high-altitude data aquisition system

    Science.gov (United States)

    1985-05-01

    A new microcomputer controlled high altitude data acquisition system was developed. The system provides a new technique for data acquisition from China's astronomical, meteorological and other high altitude experiments and opens up new territory in microcomputer applications. This microcomputer controlled high altitude data acquisition system is made up of a Z80 single board computer, 10 K memory expansion board, and keyboard and display board which can collect 16 analog signals simultaneously, and through analog/digital conversion can convert external analog signals into digital signals then encode them in a certain form through program modulation and store them on audio cassette. The data is immediately retrieved from the tape and sent to the surface microcomputer system for data processing and analysis.

  3. Micro-computed tomographic analysis of progression of artificial enamel lesions in primary and permanent teeth after resin infiltration.

    Science.gov (United States)

    Ozgul, Betul Memis; Orhan, Kaan; Oz, Firdevs Tulga

    2015-09-01

    We investigated inhibition of lesion progression in artificial enamel lesions. Lesions were created on primary and permanent anterior teeth (n = 10 each) and were divided randomly into two groups with two windows: Group 1 (window A: resin infiltration; window B: negative control) and Group 2 (window A: resin infiltration + fluoride varnish; window B: fluoride varnish). After pH cycling, micro-computed tomography was used to analyze progression of lesion depth and changes in mineral density. Resin infiltration and resin infiltration + fluoride varnish significantly inhibited progression of lesion depth in primary teeth (P 0.05). Resin infiltration is a promising method of inhibiting progression of caries lesions.

  4. Establishing a Customized Guide Plate for Osteotomy in Total Knee Arthroplasty Using Lower-extremity X-ray and Knee Computed Tomography Images

    Directory of Open Access Journals (Sweden)

    Jin Zhang

    2016-01-01

    Conclusions: A customized guide plate to create an accurate osteotomy in TKAs may be created using lower-extremity X-ray and knee CT images. This allows for shorter operative times and better postoperative alignment than the traditional surgery. Application of the digital guide plate may also result in better short-term outcomes.

  5. Micro radiography and tomography for high resolution NDT of advanced materials and microstructural components

    Science.gov (United States)

    Maisl, M.; Reiter, H.; Hoeller, P.

    The application of microradiography and microcomputed tomography for the NDT of high strength ceramics and fiber-reinforced composites is discussed. Radiography with microfocal X-ray tubes provides high-resolution radiographs using the direct projection technique. Tomography produces high-contrast images of sections of an object, and results are presented using a tomographic unit with a resolution of the order of magnitude of 20 microns.

  6. Optical coherence tomography for ultrahigh-resolution 3D imaging of cell development and real-time guiding for photodynamic therapy

    Science.gov (United States)

    Wang, Tianshi; Zhen, Jinggao; Wang, Bo; Xue, Ping

    2009-11-01

    Optical coherence tomography is a new emerging technique for cross-sectional imaging with high spatial resolution of micrometer scale. It enables in vivo and non-invasive imaging with no need to contact the sample and is widely used in biological and clinic application. In this paper optical coherence tomography is demonstrated for both biological and clinic applications. For biological application, a white-light interference microscope is developed for ultrahigh-resolution full-field optical coherence tomography (full-field OCT) to implement 3D imaging of biological tissue. Spatial resolution of 0.9μm×1.1μm (transverse×axial) is achieved A system sensitivity of 85 dB is obtained at an acquisition time of 5s per image. The development of a mouse embryo is studied layer by layer with our ultrahigh-resolution full-filed OCT. For clinic application, a handheld optical coherence tomography system is designed for real-time and in situ imaging of the port wine stains (PWS) patient and supplying surgery guidance for photodynamic therapy (PDT) treatment. The light source with center wavelength of 1310nm, -3 dB wavelength range of 90 nm and optical power of 9mw is utilized. Lateral resolution of 8 μm and axial resolution of 7μm at a rate of 2 frames per second and with 102dB sensitivity are achieved in biological tissue. It is shown that OCT images distinguish very well the normal and PWS tissues in clinic and are good to serve as a valuable diagnosis tool for PDT treatment.

  7. SU-E-P-54: Evaluation of the Accuracy and Precision of IGPS-O X-Ray Image-Guided Positioning System by Comparison with On-Board Imager Cone-Beam Computed Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, D; Wang, W; Jiang, B; Fu, D [Tianjin Medical University Cancer Institute and Hospital, Tianjin, Tianjin (China)

    2015-06-15

    Purpose: The purpose of this study is to assess the positioning accuracy and precision of IGPS-O system which is a novel radiographic kilo-voltage x-ray image-guided positioning system developed for clinical IGRT applications. Methods: IGPS-O x-ray image-guided positioning system consists of two oblique sets of radiographic kilo-voltage x-ray projecting and imaging devices which were equiped on the ground and ceiling of treatment room. This system can determine the positioning error in the form of three translations and three rotations according to the registration of two X-ray images acquired online and the planning CT image. An anthropomorphic head phantom and an anthropomorphic thorax phantom were used for this study. The phantom was set up on the treatment table with correct position and various “planned” setup errors. Both IGPS-O x-ray image-guided positioning system and the commercial On-board Imager Cone-beam Computed Tomography (OBI CBCT) were used to obtain the setup errors of the phantom. Difference of the Result between the two image-guided positioning systems were computed and analyzed. Results: The setup errors measured by IGPS-O x-ray image-guided positioning system and the OBI CBCT system showed a general agreement, the means and standard errors of the discrepancies between the two systems in the left-right, anterior-posterior, superior-inferior directions were −0.13±0.09mm, 0.03±0.25mm, 0.04±0.31mm, respectively. The maximum difference was only 0.51mm in all the directions and the angular discrepancy was 0.3±0.5° between the two systems. Conclusion: The spatial and angular discrepancies between IGPS-O system and OBI CBCT for setup error correction was minimal. There is a general agreement between the two positioning system. IGPS-O x-ray image-guided positioning system can achieve as good accuracy as CBCT and can be used in the clinical IGRT applications.

  8. Magnetic resonance tomography-guided interventional procedure for diagnosis of prostate cancer; MRT-gezielte interventionelle Verfahren zur Abklaerung des Prostatakarzinoms

    Energy Technology Data Exchange (ETDEWEB)

    Schernthaner, M.; Helbich, T.H.; Fueger, B.J.; Memarsadeghi, M.; Stiglbauer, A.; Linhart, H.G.; Doan, A.; Pinker, K.; Brader, P. [Medizinische Universitaet Wien, Univ.-Klinik fuer Radiodiagnostik, Division fuer Molekulare und Gender-Bildgebung, Wien (Austria); Margreiter, M. [Medizinische Universitaet Wien, Univ.-Klinik fuer Urologie, Wien (Austria)

    2011-11-15

    In recent years magnetic resonance imaging (MRI) has been increasingly established in the diagnosis of prostate cancer in addition to transrectal ultrasonography (TRUS). The use of T2-weighted imaging allows an exact delineation of the zonal anatomy of the prostate and its surrounding structures. Other MR imaging tools, such as dynamic contrast-enhanced T1-weighted imaging or diffusion-weighted imaging allow an inference of the biochemical characteristics (multiparametric MRI). Prostate cancer, which could only be diagnosed using MR imaging or lesions suspected as being prostate cancer, which are localized in the anterior aspect of the prostate and were missed with repetitive TRUS biopsy, need to undergo MR guided biopsy. Recent studies have shown a good correlation between MR imaging and histopathology of specimens collected by MR-guided biopsy. Improved lesion targeting is therefore possible with MR-guided biopsy. So far data suggest that MR-guided biopsy of the prostate is a promising alternative diagnostic tool to TRUS-guided biopsy. (orig.) [German] Neben dem transrektalen Ultraschall (TRUS) hat sich in den letzten Jahren die MRT als nichtinvasive Methode zur Bildgebung von Prostatatumoren etabliert. Mittels T2-gewichteter Sequenzen ist eine exakte anatomische Darstellung der Prostata und ihrer umliegenden Strukturen moeglich. Andere MRT-Techniken ermoeglichen Rueckschluesse auf das biologische Verhalten des Tumors: dynamische kontrastmittelverstaerkte T1-gewichtete Sequenzen zur Darstellung der Angiogenese, diffusionsgewichtete Aufnahmen zur Beurteilung der Zelldichte und die Spektroskopie zur Bestimmung von Gewebemetaboliten wie Cholin und Kreatin (multiparametrische Bildgebung). Prostatatumoren, die nur mittels MRT nachweisbar sind oder verdaechtige Tumoren, die hauptsaechlich anterior in der Prostata lokalisiert sind und in wiederholten TRUS-gezielten Biopsien verfehlt wurden, benoetigen eine MRT-gezielte Biopsie zur Diagnosesicherung. Die bisherigen

  9. The Training of Microcomputer Users: Insights from Two Disciplines.

    Science.gov (United States)

    Stine, Walter D.; Wildemuth, Barbara M.

    1992-01-01

    Research in human computer interaction and instructional design can provide insights into effective methods for training microcomputer users. Suggestions include utilizing error recognition and recovery, development of mental models, simplification of documentation, and using cognitive approaches that allow transfer of knowledge to new situations.…

  10. Online Searching with a Microcomputer--Getting Started.

    Science.gov (United States)

    Casbon, Susan

    1983-01-01

    Based on online searching experiences on microcomputer at a small liberal arts college, this article outlines for the novice advantages and disadvantages of micro-searching, legal implications, future trends, and factors to consider in selecting hardware and software. A 16-item bibliography arranged in order of usefulness and 10 references are…

  11. Microcomputer Learning Project. Willow Creek School Division No. 28.

    Science.gov (United States)

    Millar, Garnet; MacLeod, Alan

    Comparative research was conducted using gifted and average upper elementary and junior high school students to determine the effectiveness of utilizing microcomputers for the development of computer literacy and the implementation of curriculum courseware. Eighty students were selected as the treatment group and received instruction in the…

  12. The Surface Features of Four Microcomputer Reading Programs.

    Science.gov (United States)

    Bradley, Virginia N.

    1984-01-01

    Uses the Bradley Inventory of Reading Comprehension Software to evaluate surface characteristics (including documentation and instructional design) of microcomputer reading comprehension programs produced by Scott Foresman, Random House, Control Data Corporation, and Basic Learning Systems. All four programs received high scores, but the Scott…

  13. Use of Microcomputers for Spelling Assessment: Reasons to Be Cautious.

    Science.gov (United States)

    Varnhagen, Stanley; Gerber, Michael M.

    1984-01-01

    Two versions, via microcomputer, of the Test of Written Spelling were administered to underachieving students from a regular third-grade class and from an upper-grade, self-contained class for learning handicapped (LH) students. Results indicated that students took less time and spelled more words correctly on the standard written version.…

  14. Utilization of the Microcomputer in the Mathematics Classroom.

    Science.gov (United States)

    Pruett, Poppy L.; And Others

    1993-01-01

    Reports a study investigating the instructional use of microcomputers by secondary mathematics teachers, and discusses results from a sample of 128 completed questionnaires showing that computer utilization is hampered by inadequate access to equipment, lack of software appropriate to the mathematics curricula, and a lack of guidance for…

  15. An Observational Study of Social Behavior in Microcomputer Classrooms.

    Science.gov (United States)

    Feldmann, Shirley C.; And Others

    1991-01-01

    This study examined the effects of five variables--student grouping at the computer, keyboarding status, academic discipline, student gender, and gender of partner--on student social behavior, both verbal and affective, in microcomputer classrooms in a public business high school. The effect of these variables on teacher behavior was also…

  16. Integrating Microcomputers and Microelectronics into the Physics Curriculum.

    Science.gov (United States)

    Gale, Douglas S.

    1980-01-01

    Describes an interdisciplinary microcomputer and microelectronics program offered jointly by the Physics and Computer Science Departments of East Texas State University. The program operates on both the graduate and undergraduate level. Content as well as structure of the program are discussed. (Author/DS)

  17. Multi-microcomputer system for Monte-Carlo calculations

    CERN Document Server

    Berg, B; Krasemann, H

    1981-01-01

    The authors propose a microcomputer system that allows parallel processing for Monte Carlo calculations in lattice gauge theories, simulations of high energy physics experiments and many other fields of current interest. The master-n-slave multiprocessor system is based on the Motorola MC 6800 microprocessor. One attraction of this processor is that it allows up to 16 M Byte random access memory.

  18. Matrix algebra routines for the Acorn Archimedes microcomputer: example applications.

    Science.gov (United States)

    Fielding, A

    1988-08-01

    A set of matrix algebra routines have been written, as BASICV procedures, for the Acorn Archimedes microcomputer. It is shown that these procedures are executed so quickly that programs, which require matrix algebra computations, can be written in interpreted BASIC. Two example applications, reciprocal averaging and principal components analysis, are demonstrated.

  19. Planning the Use of Microcomputers in Higher Education Administration.

    Science.gov (United States)

    Slovacek, Simeon P.; Dolence, Michael G.

    The process of planning the role of the microcomputer in higher education administration is investigated through a survey of a sample of universities and colleges in California engaged in such efforts, and through a review of literature in education as well as computing. A major objective of the study was to systematically investigate the…

  20. Use of Microcomputers for Spelling Assessment: Reasons to Be Cautious.

    Science.gov (United States)

    Varnhagen, Stanley; Gerber, Michael M.

    1984-01-01

    Two versions, via microcomputer, of the Test of Written Spelling were administered to underachieving students from a regular third-grade class and from an upper-grade, self-contained class for learning handicapped (LH) students. Results indicated that students took less time and spelled more words correctly on the standard written version.…

  1. A Micro-Computer Based Tutor for Teaching Arithmetic Skills.

    Science.gov (United States)

    Attisha, M.; Yazdani, M.

    1983-01-01

    Describes a knowledge-based tutoring system which provides pupil interaction with the microcomputer to diagnose pupils' errors in subtraction operations. Current subtraction methods; nature and origin of subtraction errors; and the structure, achievements, and future developments of the computer system are included. Thirteen references and a…

  2. Microcomputer-Based Digital Signal Processing Laboratory Experiments.

    Science.gov (United States)

    Tinari, Jr., Rocco; Rao, S. Sathyanarayan

    1985-01-01

    Describes a system (Apple II microcomputer interfaced to flexible, custom-designed digital hardware) which can provide: (1) Fast Fourier Transform (FFT) computation on real-time data with a video display of spectrum; (2) frequency synthesis experiments using the inverse FFT; and (3) real-time digital filtering experiments. (JN)

  3. An Integrated Library System from Existing Microcomputer Programs.

    Science.gov (United States)

    Kuntz, Lynda S.

    1988-01-01

    Demonstrates how three commercial microcomputer software packages--PC-Talk III, Wordstar, and dBase III--were combined to produce an integrated library system at the U.S. Army Concepts Analysis Agency library. The retrospective conversion process is discussed, and the four modules of the system are described: acquisitions/cataloging; online…

  4. Instructional Microcomputer Applications by Business Teachers in Minnesota.

    Science.gov (United States)

    Lambrecht, Judith J.

    Data were collected from Minnesota secondary and postsecondary business teachers regarding their instructional microcomputer applications and their attitudes about several instructional computing issues. Usable surveys were returned by 342 teachers in 236 schools. The predominant brand of computer at the secondary level was the Apple II; most…

  5. Microcomputers and School Libraries in the United Kingdom: Part II.

    Science.gov (United States)

    Pain-Lewins, Helen; Watson, Linda

    1990-01-01

    Describes study of seven local education authorities in the United Kingdom which was conducted to discover how models of microcomputer use were being adopted by school libraries. Highlights include database information retrieval; computerized catalogs; improving students' information-handling skills; curriculum-centered plans; integrated systems;…

  6. Microcomputers and School Libraries in the United Kingdom: Part I.

    Science.gov (United States)

    Pain-Lewins, Helen; Watson, Linda

    1990-01-01

    Discussion of the use of microcomputers in school libraries in the United Kingdom focuses on three models of school library computerization: (1) a library management-centered model, which addresses routine library operations; (2) a pupil-centered information skills model; and (3) a curriculum-centered model, which furthers pupil learning in…

  7. Using a Microcomputer to Communicate: Part 2: Specialized Software.

    Science.gov (United States)

    Fenichel, Carol Hansen; Murphy, John J.

    1985-01-01

    Discusses microcomputer software designed specifically to be used in the online bibliographic database search process. The specialized communications software discussed includes programs that aid in database selection, logging on, uploading, searching, downloading, post-processing, and recordkeeping. A directory of specialized communications…

  8. WE-G-BRF-06: Positron Emission Tomography (PET)-Guided Dynamic Lung Tumor Tracking for Cancer Radiotherapy: First Patient Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Yang, J; Loo, B; Graves, E [Stanford University, Stanford, CA (United States); Yamamoto, T [UC Davis School of Medicine, Sacramento, CA (United States); Keall, P [University of Sydney, Camperdown (Australia)

    2014-06-15

    Purpose: PET-guided dynamic tumor tracking is a novel concept of biologically targeted image guidance for radiotherapy. A dynamic tumor tracking algorithm based on list-mode PET data has been developed and previously tested on dynamic phantom data. In this study, we investigate if dynamic tumor tracking is clinically feasible by applying the method to lung cancer patient PET data. Methods: PET-guided tumor tracking estimates the target position of a segmented volume in PET images reconstructed continuously from accumulated coincidence events correlated with external respiratory motion, simulating real-time applications, i.e., only data up to the current time point is used to estimate the target position. A target volume is segmented with a 50% threshold, consistently, of the maximum intensity in the predetermined volume of interest. Through this algorithm, the PET-estimated trajectories are quantified from four lung cancer patients who have distinct tumor location and size. The accuracy of the PET-estimated trajectories is evaluated by comparing to external respiratory motion because the ground-truth of tumor motion is not known in patients; however, previous phantom studies demonstrated sub-2mm accuracy using clinically derived 3D tumor motion. Results: The overall similarity of motion patterns between the PET-estimated trajectories and the external respiratory traces implies that the PET-guided tracking algorithm can provide an acceptable level of targeting accuracy. However, there are variations in the tracking accuracy between tumors due to the quality of the segmentation which depends on target-to-background ratio, tumor location and size. Conclusion: For the first time, a dynamic tumor tracking algorithm has been applied to lung cancer patient PET data, demonstrating clinical feasibility of real-time tumor tracking for integrated PET-linacs. The target-to-background ratio is a significant factor determining accuracy: screening during treatment planning would

  9. Computer-Guided-Teaching: An Effective Aid for Group Instruction.

    Science.gov (United States)

    Hativa, Nira

    1984-01-01

    Describes a special application of the microcomputer for small and large group instruction called Computer-Guided-Teaching (CGT). Effective teaching strategies incorporated in CGT lessons are discussed, and a description of a formal geometry course illustrates their use in CGT lessons. (MBR)

  10. Computed Tomography-Guided Methylene Blue Labeling Prior to Thoracoscopic Resection of Small Deeply Placed Pulmonary Nodules. Do We Really Need Palpation?

    Science.gov (United States)

    Findik, Gokturk; Demiröz, S Mustafa; Apaydın, Selma Mine Kara; Ertürk, Hakan; Biri, Suzan; Incekara, Funda; Aydogdu, Koray; Kaya, Sadi

    2017-08-01

    Background Video-assisted thoracic surgery (VATS) is widely used for thoracic surgery operations, and day by day it becomes routine for the excision of undetermined pulmonary nodules. However, it is sometimes hard to reach millimetric nodules through a VATS incision. Therefore, some additional techniques were developed to reach such nodules little in size and which are settled on a challenging localization. In the literature, coils, hook wires, methylene blue, lipidol, and barium staining, and also ultrasound guidance were described for this aim. Herein we discuss our experience with CT-guided methylene blue labeling of small, deeply located pulmonary nodules just before VATS excision. Method From April 2013 to October 2016, 11 patients with millimetric pulmonary nodules (average 8, 7 mm) were evaluated in our clinic. For all these patients who had strong predisposing factors for malignancy, an 18F-FDG PET-CT scan was also performed. The patients whose nodules were decided to be excised were consulted the radiology clinic. The favorable patients were taken to CT room 2 hours prior to the operation, and CT-guided methylene blue staining were performed under sterile conditions. Results Mean nodule size of 11 patients was 8.7 mm (6, 2-12). Mean distance from the visceral pleural surface was 12.7 mm (4-29.3). Four of the nodules were located on the left (2 upper lobes, 2 lower lobes), and seven of them were on the right (four lower lobes, two upper lobes, one middle lobe). The maximum standardized uptake values (SUV max) on 18F-FDG PET/CT scan ranged between 0 and 2, 79. Conclusion CT-guided methylene blue staining of millimetric deeply located pulmonary nodules is a safe and feasible technique that helps surgeon find these undetermined nodules by VATS technique without any need of digital palpation. Georg Thieme Verlag KG Stuttgart · New York.

  11. SCANS (Shipping Cask ANalysis System) a microcomputer-based analysis system for shipping cask design review: User`s manual to Version 3a. Volume 1, Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    Mok, G.C.; Thomas, G.R.; Gerhard, M.A.; Trummer, D.J.; Johnson, G.L. [Lawrence Livermore National Lab., CA (United States)

    1998-03-01

    SCANS (Shipping Cask ANalysis System) is a microcomputer-based system of computer programs and databases developed at the Lawrence Livermore National Laboratory (LLNL) for evaluating safety analysis reports on spent fuel shipping casks. SCANS is an easy-to-use system that calculates the global response to impact loads, pressure loads and thermal conditions, providing reviewers with an independent check on analyses submitted by licensees. SCANS is based on microcomputers compatible with the IBM-PC family of computers. The system is composed of a series of menus, input programs, cask analysis programs, and output display programs. All data is entered through fill-in-the-blank input screens that contain descriptive data requests. Analysis options are based on regulatory cases described in the Code of Federal Regulations 10 CFR 71 and Regulatory Guides published by the US Nuclear Regulatory Commission in 1977 and 1978.

  12. 基于三维微焦点CT图像对高性能混凝土内部缺陷的测量和分析%Measurement and analysis of defects in high-performance concrete with three-dimensional micro-computer tomography

    Institute of Scientific and Technical Information of China (English)

    郭丽萍; Andrea Carpinteri; 孙伟; 秦文超

    2009-01-01

    为了揭示粉煤灰和磨细矿渣对混凝土微观结构初始缺陷的影响规律,采用高分辨率X-射线微焦点CT(X-ray Micro-CT)图像对具有不同胶凝材料的4个系列高性能混凝土进行了研究.混凝土微观结构和缺陷过滤之后的高分辨率三维图像均由Micro-CT配套的图像软件进行了重建.基于二维和三维图像分析得到了混凝土内部缺陷的尺寸分布和体积分数,并与常温饱水法的试验结果进行了对比.研究结果显示:矿物掺和料作为胶凝材料加入混凝土之后,由于其颗粒填充效应和火山灰效应,显著改变了硬化混凝土的微观结构特征以及初始缺陷的尺寸和空间分布特征;在水胶比和集料尺寸分布保持不变的条件下,矿物掺和料的掺入与否,是引起高性能混凝土展示出不同力学特性的主要原因.%In order to investigate the effects of two mineral admixtures(i.e.,fly ash and ground slag)on initial defects existing in concrete microstructures,a high-resolution X-ray micro-CT(micro-focus computer tomography)is employed to quantitatively analyze the initial defects in four series of high-performance concrete(HPC)specimens with additions of different mineral admixtures.The high-resolution 3D images of microstructures and filtered defects are reconstructed by micro-CT software.The size distribution and volume fractions of initial defects are analyzed based on 3D and 2D micro-CT images.The analysis results are verified by experimental results of water-suction tests.The results show that the additions of mineral admixtures in concrete as cementitious materials greatly change the geometrical properties of the microstructures and the spatial features of defects by physical-chemistry actions of these mineral admixtures.ThiS is the major cause of the differences between the mechanical behaviors of HPC with and witIlout mineral admixtures when the water-to-binder ratio and the size distribution of aggregates are

  13. Quality assurance of onboard megavoltage computed tomography imaging and target localization systems for on- and off-line image-guided radiotherapy.

    Science.gov (United States)

    Langen, Katja M; Meeks, Sanford L; Pouliot, Jean

    2008-01-01

    We reviewed the quality assurance procedures that have been used to test fan- and cone-beam megavoltage-based in-room imaging systems. Phantom-based tests have been used to establish the geometric accuracy and precision of megavoltage-based systems. However, the clinical implementation of any system is accompanied by challenges that are best tested in a clinical setting using clinical images. To objectively judge and monitor image quality, a set of standard tests and phantoms can be used. The image noise and spatial and contrast resolution have been assessed using standard computed tomography phantoms. The dose to the patient resulting from the imaging procedure can be determined using calculations or measurements. The off-line use of patient images is of interest for the evaluation of dosimetric changes throughout the treatment course. The accuracy of the dosimetric calculations based on the megavoltage images has been tested for the fan- and cone-beam systems. Some of the described tests are typically performed before the clinical implementation of the imaging system; others are suited to monitor the system's performances.

  14. Ultrasound guided fluorescence molecular tomography with improved quantification by an attenuation compensated born-normalization and in vivo preclinical study of cancer

    Energy Technology Data Exchange (ETDEWEB)

    Li, Baoqiang; Berti, Romain; Abran, Maxime; Lesage, Frédéric, E-mail: frederic.lesage@polymtl.ca [Institute of Biomedical Engineering, École Polytechnique de Montréal, Montreal, Quebec H3C 3A7 (Canada); Montreal Heart Institute, Montreal, Quebec H1T 1C8 (Canada)

    2014-05-15

    Ultrasound imaging, having the advantages of low-cost and non-invasiveness over MRI and X-ray CT, was reported by several studies as an adequate complement to fluorescence molecular tomography with the perspective of improving localization and quantification of fluorescent molecular targets in vivo. Based on the previous work, an improved dual-modality Fluorescence-Ultrasound imaging system was developed and then validated in imaging study with preclinical tumor model. Ultrasound imaging and a profilometer were used to obtain the anatomical prior information and 3D surface, separately, to precisely extract the tissue boundary on both sides of sample in order to achieve improved fluorescence reconstruction. Furthermore, a pattern-based fluorescence reconstruction on the detection side was incorporated to enable dimensional reduction of the dataset while keeping the useful information for reconstruction. Due to its putative role in the current imaging geometry and the chosen reconstruction technique, we developed an attenuation compensated Born-normalization method to reduce the attenuation effects and cancel off experimental factors when collecting quantitative fluorescence datasets over large area. Results of both simulation and phantom study demonstrated that fluorescent targets could be recovered accurately and quantitatively using this reconstruction mechanism. Finally, in vivo experiment confirms that the imaging system associated with the proposed image reconstruction approach was able to extract both functional and anatomical information, thereby improving quantification and localization of molecular targets.

  15. A microcomputer based system for current-meter data acquisition

    Science.gov (United States)

    Cheng, R.T.; Gartner, J.W.

    1979-01-01

    The U.S. Geological Survey is conducting current measurements as part of an interdisciplinary study of the San Francisco Bay estuarine system. The current meters used in the study record current speed, direction, temperature, and conductivity in digital codes on magnetic tape cartridges. Upon recovery of the current meters, the data tapes are translated by a tape reader into computer codes for further analyses. Quite often the importance of the data processing phase of a current-measurement program is underestimated and downplayed. In this paper a data-processing system which performs the complete data processing and analyses is described. The system, which is configured around an LSI-11 microcomputer, has been assembled to provide the capabilities of data translation, reduction, and tabulation and graphical display immediately following recovery of current meters. The flexibility inherent in a microcomputer has made it available to perform many other research functions which would normally be done on an institutional computer.

  16. The value of ultrasound-guided biopsy of fluorodeoxy-glucose positron emission tomography (FDG-PET)-positive supraclavicular lymph nodes in patients with suspected lung cancer.

    Science.gov (United States)

    Werner, Lennart; Keller, Franziska Aebersold; Bhure, Ujwal; Roos, Justus Egidius; Tornquist, Katharina; Del Sol Pèrez-Lago, Maria; Gautschi, Oliver; Strobel, Klaus

    2017-07-11

    Accurate lymph node staging is essential for adequate prognostication and therapy planning in patients with non-small cell lung cancer (NSCLC). FDG-PET/CT is a sensitive tool for the detection of metastases, including non-palpable supraclavicular lymph node (SCLN) metastases. Histological proof of metastatic spread and mutation analysis is crucial for optimal staging and therapy. The aim of this study was to investigate the value of ultrasound-guided fine needle aspiration cytology (FNAC) and core biopsy (CB) of FDG active, non-palpable SCLN's in patients with suspicion for lung cancer. Twelve consecutive patients with suspected lung cancer and FDG-positive SCLN underwent FNAC (n = 11) and/or CB (n = 10) and were included and evaluated retrospectively in this study. Cytologic and/or histologic evaluation was performed to confirm initially suspected diagnosis (lung cancer), to confirm N3 stage, and to screen for driver mutations in lung adenocarcinoma. FNAC alone showed diagnostic success in 11/11 cases (100%), CB alone in 9/10 patients (90%), and the combination of both procedures was successful in 12/12 cases (100%). Lymph node metastases from NSCLC (7 adenocarcinoma, 2 squamous cell carcinoma) could be confirmed in 9 patients. Other diagnoses were small cell lung cancer (SCLC), breast cancer and sarcoidosis. There was enough material for immunhistochemistry in all patients. For molecular testing, material from this lymph node biopsies and lung biopsy was used. In two patients with adenocarcinoma of the lung driver mutations were detected (EGFR Exon 19 deletion and ALK rearrangement) out of the lymph node metastasis. US-guided combined FNAC and CB of FDG positive supraclavicular lymph nodes in patients with suspected lung cancer is a safe and effective procedure to confirm N3-stage and to obtain representative material for molecular testing.

  17. Simulation of Heat Transfer and Electromagnetic Fields of Protected Microcomputers

    Directory of Open Access Journals (Sweden)

    Josef Lakatos

    2006-01-01

    Full Text Available The paper presents results of collaboration between Department of mechatronics and electronics at University of Žilina and VÚVT Engineering a.s. Žilina in area of heat transfer simulations and disturbing electromagnetic radiation simulations in computer construction. The simulations results were used in development of protected microcomputer prototypes in frame of applied research at both of workplaces.

  18. Pattern-Based Medical Diagnosis on a Microcomputer*

    OpenAIRE

    Fisher, Paul R.; Kurlander, David J.

    1980-01-01

    A differential diagnosis microcomputer program has been written that utilizes both pattern-recognition and logical analysis in its algorithm. Together with auxilliary routines, the program (called DX) performs medical diagnosis, stores and retrieves patient information, creates new model symptom sets using information from the patient pool, and trains its own data matrices. Designed to be user oriented, DX can communicate the reasoning behind its decisions, thereby complementing the physician...

  19. Use of Data Base Microcomputer Software in Descriptive Nursing Research

    OpenAIRE

    Chapman, Judy Jean

    1985-01-01

    Data base microcomputer software was used to design a file for data storage and retrieval in a qualitative nursing research project. The needs of 50 breast feeding mothers from birth to four months were studied. One thousand records with descriptive nursing data were entered into the file. The search and retrieval capability of data base software facilitated this qualitative research. The findings will be discussed in three areas: (1) infant concerns, (2) postpartum concerns, and (3) breast c...

  20. A Method for Evaluation of Microcomputers for Tactical Applications.

    Science.gov (United States)

    1980-06-01

    to microcomputer systems. f. Ada Programming Language Ada , which is named after the world’s first com- puter programmer, Lady Ada Lovelace , is a very...HOL) Ada used as a program development tool for real-time processing including microprocessor applications. (2) Hosted on small development systems. 4...mainstream. The Defense Department’s Ada HOL is being developed to serve programming needs for real-time processing including 14 microprocessor

  1. The microcomputer: A tool for personal language learning

    Directory of Open Access Journals (Sweden)

    David H. Wyatt

    2013-02-01

    Full Text Available Computer-assisted methods of teaching and learning languages have been surrounded by controversy and debate for over a decade. In 1979, however, microcomputers began to appear in a form suitable for educational applications, offering for the first time an alternative to both the cost and the approach of large computer systems. The impact of the microcomputer has been limited by a number of factors, and microcomputerassisted learning is still in a relative state of infancy. The main implications for language teaching and learning are only now beginning to be understood, just as the limiting factors are starting to disappear. This paper will assess the present situation and outline some likely future developments in the use of microcomputers in language learning. Rekenaargesteunde metodes by die onderrig en aanleer van tale is reeds meer as 'n dekade lank omgewe deur meningsverskil. In 1979 egter het mikrorekenaars hulle verskyning begin maak in 'n toepaslike vorm vir opvoedkundige doeleindes. Vir die eerste keer was daar 'n alternatief vir die koste verbonde aan en die benaderingswyse van groot rekenaarstelsels. Die trefkrag van die mikrorekenaar is deur 'n aantal faktore gekortwiek en rekenaargesteunde onderrig is steeds in sy kinderskoene. Die belangrikste implikasies vir die aanleer en onderrig van tale begin nou eers deurdring soos die beperkende faktore begin verdwyn. Hierdie artikel takseer die huidige situasie en omlyn moontlike toekomstige ontwikkelings vir die gebruik van mikrorekenaars by taalaanleer.

  2. 2D-3D radiograph to cone-beam computed tomography (CBCT) registration for C-arm image-guided robotic surgery.

    Science.gov (United States)

    Liu, Wen Pei; Otake, Yoshito; Azizian, Mahdi; Wagner, Oliver J; Sorger, Jonathan M; Armand, Mehran; Taylor, Russell H

    2015-08-01

    C-arm radiographs are commonly used for intraoperative image guidance in surgical interventions. Fluoroscopy is a cost-effective real-time modality, although image quality can vary greatly depending on the target anatomy. Cone-beam computed tomography (CBCT) scans are sometimes available, so 2D-3D registration is needed for intra-procedural guidance. C-arm radiographs were registered to CBCT scans and used for 3D localization of peritumor fiducials during a minimally invasive thoracic intervention with a da Vinci Si robot. Intensity-based 2D-3D registration of intraoperative radiographs to CBCT was performed. The feasible range of X-ray projections achievable by a C-arm positioned around a da Vinci Si surgical robot, configured for robotic wedge resection, was determined using phantom models. Experiments were conducted on synthetic phantoms and animals imaged with an OEC 9600 and a Siemens Artis zeego, representing the spectrum of different C-arm systems currently available for clinical use. The image guidance workflow was feasible using either an optically tracked OEC 9600 or a Siemens Artis zeego C-arm, resulting in an angular difference of Δθ:∼ 30°. The two C-arm systems provided TRE mean ≤ 2.5 mm and TRE mean ≤ 2.0 mm, respectively (i.e., comparable to standard clinical intraoperative navigation systems). C-arm 3D localization from dual 2D-3D registered radiographs was feasible and applicable for intraoperative image guidance during da Vinci robotic thoracic interventions using the proposed workflow. Tissue deformation and in vivo experiments are required before clinical evaluation of this system.

  3. Preliminary experience on the implementation of computed tomography (CT)-based image guided brachytherapy (IGBT) of cervical cancer using high-dose-rate (HDR) Cobalt-60 source in University of Malaya Medical Centre (UMMC)

    Science.gov (United States)

    Jamalludin, Z.; Min, U. N.; Ishak, W. Z. Wan; Malik, R. Abdul

    2016-03-01

    This study presents our preliminary work of the computed tomography (CT) image guided brachytherapy (IGBT) implementation on cervical cancer patients. We developed a protocol in which patients undergo two Magnetic Resonance Imaging (MRI) examinations; a) prior to external beam radiotherapy (EBRT) and b) prior to intra-cavitary brachytherapy for tumour identification and delineation during IGBT planning and dosimetry. For each fraction, patients were simulated using CT simulator and images were transferred to the treatment planning system. The HR-CTV, IR-CTV, bladder and rectum were delineated on CT-based contouring for cervical cancer. Plans were optimised to achieve HR-CTV and IR-CTV dose (D90) of total EQD2 80Gy and 60Gy respectively, while limiting the minimum dose to the most irradiated 2cm3 volume (D2cc) of bladder and rectum to total EQD2 90Gy and 75Gy respectively. Data from seven insertions were analysed by comparing the volume-based with traditional point- based doses. Based on our data, there were differences between volume and point doses of HR- CTV, bladder and rectum organs. As the number of patients having the CT-based IGBT increases from day to day in our centre, it is expected that the treatment and dosimetry accuracy will be improved with the implementation.

  4. Measuring Abdominal Circumference and Skeletal Muscle From a Single Cross-Sectional Computed Tomography Image: A Step-by-Step Guide for Clinicians Using National Institutes of Health ImageJ.

    Science.gov (United States)

    Gomez-Perez, Sandra L; Haus, Jacob M; Sheean, Patricia; Patel, Bimal; Mar, Winnie; Chaudhry, Vivek; McKeever, Liam; Braunschweig, Carol

    2016-03-01

    Diagnostic computed tomography (CT) scans provide numerous opportunities for body composition analysis, including quantification of abdominal circumference, abdominal adipose tissues (subcutaneous, visceral, and intermuscular), and skeletal muscle (SM). CT scans are commonly performed for diagnostic purposes in clinical settings, and methods for estimating abdominal circumference and whole-body SM mass from them have been reported. A supine abdominal circumference is a valid measure of waist circumference (WC). The valid correlation between a single cross-sectional CT image (slice) at third lumbar (L3) for abdominal SM and whole-body SM is also well established. Sarcopenia refers to the age-associated decreased in muscle mass and function. A single dimensional definition of sarcopenia using CT images that includes only assessment of low whole-body SM has been validated in clinical populations and significantly associated with negative outcomes. However, despite the availability and precision of SM data from CT scans and the relationship between these measurements and clinical outcomes, they have not become a routine component of clinical nutrition assessment. Lack of time, training, and expense are potential barriers that prevent clinicians from fully embracing this technique. This tutorial presents a systematic, step-by-step guide to quickly quantify abdominal circumference as a proxy for WC and SM using a cross-sectional CT image from a regional diagnostic CT scan for clinical identification of sarcopenia. Multiple software options are available, but this tutorial uses ImageJ, a free public-domain software developed by the National Institutes of Health.

  5. Computed tomography guided percutaneous injection of a mixture of lipiodol and methylene blue in rabbit lungs: evaluation of localization ability for video-assisted thoracoscopic surgery.

    Science.gov (United States)

    Jin, Kwang Nam; Lee, Kyung Won; Kim, Tae Jung; Song, Yong Sub; Kim, Dong Il

    2014-01-01

    Preoperative localization is necessary prior to video assisted thoracoscopic surgery for the detection of small or deeply located lung nodules. We compared the localization ability of a mixture of lipiodol and methylene blue (MLM) (0.6 mL, 1:5) to methylene blue (0.5 mL) in rabbit lungs. CT-guided percutaneous injections were performed in 21 subjects with MLM and methylene blue. We measured the extent of staining on freshly excised lung and evaluated the subjective localization ability with 4 point scales at 6 and 24 hr after injections. For MLM, radio-opacity was evaluated on the fluoroscopy. We considered score 2 (acceptable) or 3 (excellent) as appropriate for localization. The staining extent of MLM was significantly smaller than methylene blue (0.6 vs 1.0 cm, Pmethylene blue (2.8 vs 2.2, P=0.010). Excellent staining was achieved in 17 subjects (81%) with MLM and 8 (38%) with methylene blue (P=0.011). An acceptable or excellent radio-opacity of MLM was found in 13 subjects (62%). An appropriate localization rate of MLM was 100% with the use of the directly visible ability and radio-opacity of MLM. MLM provides a superior pulmonary localization ability over methylene blue.

  6. Registration of a needle-positioning robot to high-resolution 3D ultrasound and computed tomography for image-guided interventions in small animals

    Science.gov (United States)

    Waspe, Adam C.; Lacefield, James C.; Holdsworth, David W.; Fenster, Aaron

    2008-03-01

    Preclinical research often requires the delivery of biological substances to specific locations in small animals. Guiding a needle to targets in small animals with an error animal imaging systems. Both techniques involve moving the needle to predetermined robot coordinates and determining corresponding needle locations in image coordinates. Registration accuracy will therefore be affected by the robot positioning error and is assessed by measuring the target registration error (TRE). A point-based registration between robot and micro-ultrasound coordinates was accomplished by attaching a fiducial phantom onto the needle. A TRE of 145 μm was achieved when moving the needle to a set of robot coordinates and registering the coordinates to needle tip locations determined from ultrasound fiducial measurements. Registration between robot and micro-CT coordinates was accomplished by injecting barium sulfate into tracks created when the robot withdraws the needle from a phantom. Points along cross-sectional slices of the segmented needle tracks were determined using an intensity-weighted centroiding algorithm. A minimum distance TRE of 194 +/- 18 μm was achieved by registering centroid points to robot trajectories using the iterative closest point (ICP) algorithm. Simulations, incorporating both robot and ultrasound fiducial localization errors, verify that robot error is a significant component of the experimental registration. Simulations of micro-CT to robot ICP registration similarly agree with the experimental results. Both registration techniques produce a TRE < 200 μm, meeting design specification.

  7. Long-term follow-up after left atrial appendage occlusion with comparison of transesophageal echocardiography versus computed tomography to guide medical therapy and data about postclosure cardioversion.

    Science.gov (United States)

    Berte, Benjamin; Jost, Christine Attenhofer; Maurer, Dominik; Fäh-Gunz, Anja; Pillois, Xavier; Naegeli, Barbara; Pfyffer, Monica; Sütsch, Gabor; Scharf, Christoph

    2017-07-04

    The use of left atrial appendage (LAA) occluders in atrial fibrillation is increasing. There are few data on the comparison between transesophageal echocardiography (TEE) and computed tomography (MDCT) assessing peridevice flow and outcome of electrical cardioversion (ECV) in these patients. Single-center prospective registry from 2009 to 2015 including all LAA occluders to analyze success and complications during implantation and follow-up. Patients having ≥1 ECV were further analyzed. TEE was performed during implantation and at 6 weeks. In a subgroup of 77 patients, we compared MDCT with TEE at 6 weeks. Overall, 135 patients (69 ± 9 years; 70% male; CHA2 DS2 -VASc score: 3.6 ± 1.4; HAS-BLED score: 2.5 ± 0.6) received a LAA occluder (Watchman, n = 73; ACP-1, n = 59; Amulet, n = 3; PVI + LAA occluder, n = 91; and LAA occluder only, n = 44). Device implantation was successful in 131 (97%). Eight patients (5.9%) had major periprocedural complications (ischemic stroke/transient ischemic attacks, n = 4, tamponade, n = 2, device thrombosis, n = 2, Dressler syndrome, n = 1). The periprocedural complication rate was similar between concomitant procedure and LAA occluder only (8/91 vs. 5/44; P = 0.6). Twelve patients (9%) died (procedure-related, n = 2; 1%) during follow-up of 44 months (IQR: 43). MDCT (n = 77) at 6 weeks showed similar peridevice flow compared to TEE (TEE: 1.5 ± 1.9 mm vs. MDCT: 1.1 ± 2.2 mm, P = 0.25). Thromboembolic events occurred in 3 patients (CVA, n = 1; TIA, n = 2) during follow-up. In total, 41 ECV were performed in 26 patients (1.6 ± 0.9/patient), 13 months (IQR: 24) after implantation (<1 month: n = 8). No ECV-related clinical complications were observed. LAA occlusion is feasible with an acceptable safety profile and few events during long-term follow-up. ECV after LAA occlusion is feasible. MDCT could help to evaluate peridevice flow. © 2017 Wiley Periodicals, Inc.

  8. Biomaterial porosity determined by fractal dimensions, succolarity and lacunarity on microcomputed tomographic images

    Energy Technology Data Exchange (ETDEWEB)

    N' Diaye, Mambaye [LUNAM Université, GEROM Groupe Etudes Remodelage Osseux et bioMatériaux-LHEA, IRIS-IBS Institut de Biologie en Santé, CHU d' Angers, 49933 ANGERS Cedex (France); Degeratu, Cristinel [LUNAM Université, GEROM Groupe Etudes Remodelage Osseux et bioMatériaux-LHEA, IRIS-IBS Institut de Biologie en Santé, CHU d' Angers, 49933 ANGERS Cedex (France); University Politehnica of Bucharest, Faculty of Applied Chemistry and Materials Science, Department of Bioresources and Polymer Science, Calea Victoriei 149, 010072, Sector 1, Bucharest (Romania); Bouler, Jean-Michel [Inserm UMR 791, LIOAD, University of Nantes, 44000 Nantes (France); Chappard, Daniel, E-mail: daniel.chappard@univ-angers.fr [LUNAM Université, GEROM Groupe Etudes Remodelage Osseux et bioMatériaux-LHEA, IRIS-IBS Institut de Biologie en Santé, CHU d' Angers, 49933 ANGERS Cedex (France)

    2013-05-01

    Porous structures are becoming more and more important in biology and material science because they help in reducing the density of the grafted material. For biomaterials, porosity also increases the accessibility of cells and vessels inside the grafted area. However, descriptors of porosity are scanty. We have used a series of biomaterials with different types of porosity (created by various porogens: fibers, beads …). Blocks were studied by microcomputed tomography for the measurement of 3D porosity. 2D sections were re-sliced to analyze the microarchitecture of the pores and were transferred to image analysis programs: star volumes, interconnectivity index, Minkowski–Bouligand and Kolmogorov fractal dimensions were determined. Lacunarity and succolarity, two recently described fractal dimensions, were also computed. These parameters provided a precise description of porosity and pores' characteristics. Non-linear relationships were found between several descriptors e.g. succolarity and star volume of the material. A linear correlation was found between lacunarity and succolarity. These techniques appear suitable in the study of biomaterials usable as bone substitutes. Highlights: ► Interconnected porosity is important in the development of bone substitutes. ► Porosity was evaluated by 2D and 3D morphometry on microCT images. ► Euclidean and fractal descriptors measure interconnectivity on 2D microCT images. ► Lacunarity and succolarity were evaluated on a series of porous biomaterials.

  9. Biomaterial porosity determined by fractal dimensions, succolarity and lacunarity on microcomputed tomographic images.

    Science.gov (United States)

    N'Diaye, Mambaye; Degeratu, Cristinel; Bouler, Jean-Michel; Chappard, Daniel

    2013-05-01

    Porous structures are becoming more and more important in biology and material science because they help in reducing the density of the grafted material. For biomaterials, porosity also increases the accessibility of cells and vessels inside the grafted area. However, descriptors of porosity are scanty. We have used a series of biomaterials with different types of porosity (created by various porogens: fibers, beads …). Blocks were studied by microcomputed tomography for the measurement of 3D porosity. 2D sections were re-sliced to analyze the microarchitecture of the pores and were transferred to image analysis programs: star volumes, interconnectivity index, Minkowski-Bouligand and Kolmogorov fractal dimensions were determined. Lacunarity and succolarity, two recently described fractal dimensions, were also computed. These parameters provided a precise description of porosity and pores' characteristics. Non-linear relationships were found between several descriptors e.g. succolarity and star volume of the material. A linear correlation was found between lacunarity and succolarity. These techniques appear suitable in the study of biomaterials usable as bone substitutes. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. A case of polyostotic osteosarcoma with kidney metastases in a dog: histopathology and microcomputed tomographic analysis.

    Science.gov (United States)

    Aguado, E; Goyenvalle, E; Guintard, C

    2014-12-01

    A 7-year- old sexually intact female Leonberg dog was evaluated for chronic lameness of the right forelimb. The bitch showed mild hyperthermia (39.3°C), a decrease in its activity, a capricious appetite, a high weight loss (4 kg in 15 days) and a right foreleg lameness. A careful clinical examination revealed a deformation of the right proximal humerus and right tibia. Radiographic examination of the right tibia, right humerus showed osteolysis of both cortical and trabecular bone with a periosteal bone proliferation in the vicinal soft tissues. The owner having refused a bone biopsy, a treatment with NSAIDs and antibiotics was prescribed. After a marked improvement during the first two weeks, an increase in lameness and activity was observed. At that time, the owner accepted the bone biopsy. Histopathologic examination evidenced an osteosarcoma but the amount of available tissue was limited. Due to the poor prognosis, he declined treatment and decided to euthanize the dog. An osteosarcoma with a large chondroid component was observed at autopsy together with ossifying kidney metastases. Histological findings revealed a grade III osteosarcoma. Conventional and undecalcified histology and X-ray microcomputed tomography findings evidenced a large and partially mineralized osteoid part with a sunburst extension in the soft tissues. This is the first time that microCT and undecalcified analyses of an osteosarcoma are presented. The osteolytic and metaplastic bone foci were easily demonstrated by this method.

  11. Gross, histologic, and micro-computed tomographic anatomy of the lacrimal system of snakes.

    Science.gov (United States)

    Souza, Nicole M; Maggs, David J; Park, Shin Ae; Puchalski, Sarah M; Reilly, Christopher M; Paul-Murphy, Joanne; Murphy, Christopher J

    2015-01-01

    To describe the lacrimal system of snakes using contrast micro-computed tomography (micro-CT) with 3-dimensional reconstruction, fluorescein passage ('Jones') testing, histology, and gross dissection. One royal python and 19 snake cadavers representing 10 species. Direct observation following injection of fluorescein into the subspectacular space, micro-CT following injection of three contrast agents into the subspectacular space, gross dissection following injection of latex into the subspectacular space, and histopathology. Injection of fluorescein confirmed patency, but not course of the lacrimal duct. Barium enabled clear visualization of the lacrimal duct, whereas two iodinated contrast agents proved inadequate. Collectively, micro-CT, anatomic dissections, and histology suggest tears are produced by a single, large, serous, retrobulbar gland, released into the subspectacular space via several ductules, and drained through a single punctum originating in the ventronasal subspectacular space, and the lacrimal duct, which takes one of three routes of variable tortuosity before opening into the oral cavity in close association with the opening of the duct of the vomeronasal organ. The ophidian lacrimal duct has a generally tortuous course, and the details of its anatomy are species-variable. The tortuous course of the duct likely predisposes snakes to duct occlusion and must be considered when planning medical and surgical interventions in snakes with pseudobuphthalmos and subspectacular abscessation. © 2014 American College of Veterinary Ophthalmologists.

  12. Quantitative analysis of the cochlea using three-dimensional reconstruction based on microcomputed tomographic images.

    Science.gov (United States)

    Shin, Kang-Jae; Lee, Ju-Young; Kim, Jeong-Nam; Yoo, Ja-Young; Shin, Chuog; Song, Wu-Chul; Koh, Ki-Seok

    2013-07-01

    The aim of this study was to provide data on various dimensions of the normal cochlea using three-dimensional reconstruction based on high-resolution micro-CT images. The petrous parts of 39 temporal bones were scanned by micro-computed tomography (CT) with a slice thickness of 35 μm. The micro-CT images were used in reconstructing three-dimensional volumes of the bony labyrinth using computer software. The volumes were used to measure 12 dimensions of the cochlea, and statistical analysis was carried out. The dimensions of cochleae varied widely between different specimens. The mean height and length of the cochlea were 3.8 and 9.7 mm, respectively. The angle between the basal and middle turns was slightly larger in males than in females, while none of the other 11 dimensions differed significantly between males and females. The cochlear accessory canals were observed in about half of the cases (51.3%). Correlation analysis among measured items revealed positive correlations among several of the measured dimensions. The present study could investigate the detailed anatomy of the normal cochlea using high-resolution imaging technologies. The results of the present study could be helpful for the precise diagnosis of congenital cochlear malformations and for producing optimized cochlear implants.

  13. Osseointegration of oral implants after delayed placement in rabbits: a microcomputed tomography and histomorphometric study

    NARCIS (Netherlands)

    Anil, S.; Cuijpers, V.M.J.I.; Preethanath, R.S.; Aldosari, A.A.; Jansen, J.A.

    2013-01-01

    Purpose: This study compared osseointegration of implants placed 14 days after implant site preparation with that of immediately placed implants in rabbit femurs. Materials and Methods: Implants were placed bilaterally in the femoral condyles of 12 rabbits. On one side, the implants were placed 14 d

  14. 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 (pprocess 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.

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

    Science.gov (United States)

    2011-01-01

    periosteal surface of the beams, which were loaded in tension under bending, in order to concentrate damage ahead of the notch during loading. The...0.6 mm from the periosteal surface and 0.2 mm from the beam sides (Fig. 2). Gaussian smoothing was applied to suppress noise and 3D images were...and 40% reduction in stiffness were not statistically significant [10]. Bovine tibial cortical bone specimens loaded in cyclic uniaxial compression

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

    DEFF Research Database (Denmark)

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

    2016-01-01

    INTRODUCTION: A major complication of haemophilia is haemophilic arthropathy (HA), a debilitating disorder with an incompletely defined pathobiology. High-resolution imaging may provide new knowledge about onset and progression of HA, and thereby support identification of new treatment...... 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......CT, 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...

  17. Micro-Computed Tomography of Tooth Volume Changes Following Post Removal.

    Science.gov (United States)

    Kim, Jiyeon J; Alapati, Satish; Knoernschild, Kent L; Jeong, Yong-Hoon; Kim, Do Gyoon; Lee, Damian J

    2017-08-01

    To measure tooth volume change before and after post removal using micro-CT and to compare the difference among various combinations of prefabricated post and cement systems. Forty-eight extracted maxillary anterior teeth and mandibular canines were sectioned 13 mm from the apex. Root canals were properly instrumented. Preparations were filled with gutta percha using lateral condensation. Post space was prepared with a touch and heat device, leaving 5 mm of gutta percha from the apex. Specimens were scanned with micro-CT to establish objective baseline volume and divided into two groups of post systems: stainless steel (SS) ParaPost and glass-fiber reinforced composite (FRC) post. Half the posts for each group were cemented with Ketac Cem radiopaque glass-ionomer cement, and the other half with SpeedCEM dual-curing resin cement. The posts and residual cement were removed by the same operator, using the ultrasonic vibration technique under an endodontic operating microscope. The remaining tooth root structure was scanned again using micro-CT with volume reported (mm(3) ). The statistical difference between the combination of posts and cements was measured using the Kruskal-Wallis ANOVA test (α = 0.001). The independent variables were evaluated separately using post hoc Tukey examination to determine which groups resulted in a statistically significant difference. There was a statistical difference of tooth root volume change among the groups. Post hoc exam revealed a statistically significant difference in tooth root volume change between group 1 (SS + GI) and the other groups (α = 0.0002). Compared to other post and cement combinations, serrated parallel-sided SS posts cemented with GI cement had the most tooth root structure loss upon post removal using the ultrasonic vibration technique. © 2016 by the American College of Prosthodontists.

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

    Science.gov (United States)

    2009-01-01

    were inhibited by difficulty correlating levels of fluorescence to gold concentration . An experimental apparatus for using bone tissue specimens as a...verify the presence of Au NPs bound to the surface of the HA crystals (Fig. 11). The supernatant solution was collected and the residual gold ... concentration was measured using inductively coupled plasma optical emission spectroscopy (ICP-OES). The kinetics of binding with time showed that

  19. Micro-computed tomography study of the abnormal osseous extensions of sella turcica.

    Science.gov (United States)

    Skrzat, J; Kozerska, M; Wróbel, A

    2014-02-01

    The paper presents anatomical considerations on the abnormal ossification, which occurred around the dorsum of the sella turcica in the human skull of the female individual. Probably the morphological alterations of the sellar region were associated with extensive heterotopic ossification of the dura mater attached to the dorsum of the sella turcica and the posterior clinoid processes. The analysis of gray values of the voxels representing the areas of abnormal ossification indicated on variation in bone density in the entire sample. We have established that the highest mineralisation of bony tissue occurred in the marginal parts of the osseous extensions deriving from the posterior clinoid processes. The ossified parts of dura mater attached to the posterior clinoid processes showed significantly higher content of the hydroxyapatite (1.9 g/cm3) than the dorsum of the sella turcica (1.0 g/cm3).

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

    Science.gov (United States)

    2008-01-01

    proximal femur: influence of age and osteoarthritis on damage morphology and regional distribution. Bone 31, 697–702. Frost, H.M., 1960. Presence of...remodeling processes are no longer in equilibrium. In active individuals, such as athletes or military recruits, damage may accumulate too quickly for the

  1. Biópsia pulmonar percutânea guiada por tomografia computadorizada: dados de um hospital Percutaneous computed tomography-guided biopsy of the lung: data from a hospital

    Directory of Open Access Journals (Sweden)

    Emílio Humberto Carazzai

    2006-08-01

    Full Text Available OBJETIVO: Apresentar a experiência do serviço de radiologia do Hospital Santa Cecília, São Paulo, SP, no manejo das biópsias pulmonares por aspiração através de agulha fina e biópsias por fragmentos guiadas por tomografia computadorizada e a análise de sua importância e associação com suas complicações. MATERIAIS E MÉTODOS: Foram analisadas 168 biópsias guiadas por tomografia, sendo 84 em homens e 84 em mulheres. Utilizou-se a técnica de biópsia por aspiração por agulha fina em 64 pacientes, a técnica de biópsia por fragmento em 68 pacientes e ambas as técnicas em 36 pacientes. RESULTADOS: Pneumotórax ocorreu em 38 pacientes e a hemorragia pulmonar, em dez pacientes. As dimensões das lesões biopsiadas variaram de 0,5 cm até 15 cm. O diagnóstico foi realizado na primeira tentativa em 132 casos e na segunda tentativa em dez casos. CONCLUSÃO: A acurácia das biópsias aspirativas por agulha fina e por fragmento de lesões pulmonares depende do tamanho da lesão e da colaboração do paciente. Essas técnicas são relativamente seguras e têm acurácia diagnóstica elevada quando feitas por um profissional experiente.OBJECTIVE: To present the experience of Santa Cecília Hospital (São Paulo, SP, Brazil radiology service in the handling of computed tomography-guided fine-needle aspiration biopsy and percutaneous core biopsy of pulmonary lesions, analyzing their importance and associated complications. MATERIALS AND METHODS: One hundred and sixty-eight computed tomography-guided biopsies were performed in 84 men and 84 women. Sixty-four patients underwent fine-needle aspiration biopsy, 68 underwent percutaneous core biopsy and 36 patients underwent both techniques. RESULTS: Pneumothorax occurred in 38 patients, and pulmonary hemorrhage in then cases. The biopsied lesions ranged in size from 0.5 to 15 cm. The diagnosis was achieved at the first attempt in 132 cases and at the second attempt in ten cases. CONCLUSION: The

  2. Effects of Microcomputer versus Electric Element Typewriter Instruction on Straight Copy and Production Keyboarding Performance.

    Science.gov (United States)

    Davison, Leslie J.

    1990-01-01

    One group of secondary keyboarding students was taught on typewriters and switched to microcomputers after six weeks, the other used microcomputers first, then typewriters. Using computers, students showed faster completion times and fewer typographical errors. Transfer from computers to typewriters slowed times and increased errors. Overall,…

  3. Usage Patterns at Western Kentucky University Microcomputer Lab (U.S.A.): Past and Present.

    Science.gov (United States)

    Hahn, Jung Sun

    This paper describes the results of a study of the microcomputer use patterns reflected by more than 13,000 users' records from the microcomputer laboratory at Western Kentucky University for 1983 to 1986. The data analyzed focused on: (1) numbers of users; (2) frequent user groups; (3) sex differences; (4) prime time usage; (5) the use of…

  4. Microcomputers and Evaluation Research: Potential Benefits and Problems. Paper and Report Series, No. 98.

    Science.gov (United States)

    Gray, Peter J.

    This paper deals with two questions: (1) what are the the applications that might be made of microcomputers in evaluation? and (2) what are the kinds of problems (personnel, organizational, and technical) that must be overcome if microcomputers are to be used effectively? The applications include proposals and planning, management, data…

  5. A Design Method for a State Feedback Microcomputer Controller of a Wide Bandwidth Analog Plant.

    Science.gov (United States)

    1983-12-01

    METHOD . . . .... 16 1. State Feedback Control System . . . . . . 16 2. Microcomputer Controller Design with Time Delay . . . . . . . . . . . . . . . . 18...90 C. DESIGN OF STATE FEEDBACK CONTROL SYSTEM WITH MICROCOMPUTER . . . . . . . . . . . . . . . . 91 1. Control Algorithm...FIGURES 2.1 Signal Flow Diagram of State Feedback System . . 17 2.2 Feedback Control System with PD Control . . . . 18 2.3 Bode Diagram of Eqn. 2.7

  6. The Development and Application of Advanced Video and Microcomputer- Based Command and Control (C2) Systems

    Science.gov (United States)

    1982-12-01

    video recorders; microcomputers; spatial data management; shared data microcomputer software design; 6502 Microprocessor; APPLE II M AUSTRAC -T (CaeUE...maintain a key role in supporting the continued development of the technology. In 1979, work began at the Computer Corporation of Amer- ica to

  7. A DMA interface between a Biomation 8100 and an Intel MDS-800 microcomputer development system.

    Science.gov (United States)

    Lynk, E T

    1979-09-01

    An interface is described which permits high-speed data transfer between a Biomation 8100 transient recorder and an Intel MDS-800 microcomputer system equipped with an MDS-501 DMA (direct memory access) channel controller. The interface is especially useful for data acquisition situations in which many successive traces must be recorded. For example, signal averaging can be performed within the microcomputer system.

  8. Using the Analogue Input Port on the BBC Microcomputer: Some General Principles and a Specific Example.

    Science.gov (United States)

    Millar, R. H.; Underwood, C. I.

    1984-01-01

    Discusses an easy way of interfacing physics experiments to a microcomputer, providing information on the "analog input port" of a BBC microcomputer. Also describes a capacitor discharge experiment with suggestions for several student activities such as investigating decay curve shapes. Program listing is available from author. (DH)

  9. MicroComputers: New Directions and Methods for the Preparation of Special Education Personnel.

    Science.gov (United States)

    McCann, Scott K.; Kelemen, Eve J.

    1984-01-01

    The article discusses the dual role of the microcomputer as a focus and a medium for training special educators. Current issues, applications, and outcomes surrounding the impact of microcomputer technology on the preparation of special education personnel are explored. Implications for inservice and preservice training of special educators are…

  10. Doppler Tomography

    CERN Document Server

    Marsh, T R

    2000-01-01

    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 a...

  11. Mathematics for seismic data processing with basic microcomputer programs

    Energy Technology Data Exchange (ETDEWEB)

    Camina, A.R.; Janacek, G.J.

    1985-01-01

    The new, refined techniques for exploration of oil and gas and the growth of computer uses have led to a far wider application of mathematics, and the interpretation of seismic data in particular. The authors explain in detail the mathematical principles required for signal processing and clarify for the reader what are sometimes very complex concepts. The book starts at precalculus level and progresses through to advanced theories and principles. A collection of BASIC microcomputer programs is included to give the reader a practical feel for the mathematics and their applications to these techniques.

  12. Sand and gravel mine operations and reclamation planning using microcomputers

    Energy Technology Data Exchange (ETDEWEB)

    Ariffin, J.B.

    1990-02-01

    The purpose of this study is to focus on the application of microcomputers, also known as personal computers, in planning for sand and gravel mine operations and reclamation at a site in Story County, Iowa. This site, called the Arrasmith Pit, is operated by Martin Marietta Aggregates, Inc. The Arrasmith site, which encompasses an area of about 25 acres, is a relatively small site for aggregate mining. However, planning for the concurrent mine operation and reclamation program at this site is just as critical as with larger sites and the planning process is the same.

  13. Microcomputers in Art Education: An Introductory Vocabulary for Art Teachers Who Need To Make Sense of New Technology.

    Science.gov (United States)

    Brouch, Ginny

    This booklet provides introductory information and terminology for art teachers concerning the use of microcomputers in elementary and secondary school art classes. Part 1 describes the sizes and uses of microcomputers and distinguishes between maxi, mini, micro, lap, and handheld computers. Part 2 discusses: (1) basic microcomputer hardware and…

  14. Salicylic Acid-Based Polymers for Guided Bone Regeneration Using Bone Morphogenetic Protein-2.

    Science.gov (United States)

    Subramanian, Sangeeta; Mitchell, Ashley; Yu, Weiling; Snyder, Sabrina; Uhrich, Kathryn; O'Connor, J Patrick

    2015-07-01

    Bone morphogenetic protein-2 (BMP-2) is used clinically to promote spinal fusion, treat complex tibia fractures, and to promote bone formation in craniomaxillofacial surgery. Excessive bone formation at sites where BMP-2 has been applied is an established complication and one that could be corrected by guided tissue regeneration methods. In this study, anti-inflammatory polymers containing salicylic acid [salicylic acid-based poly(anhydride-ester), SAPAE] were electrospun with polycaprolactone (PCL) to create thin flexible matrices for use as guided bone regeneration membranes. SAPAE polymers hydrolyze to release salicylic acid, which is a nonsteroidal anti-inflammatory drug. PCL was used to enhance the mechanical integrity of the matrices. Two different SAPAE-containing membranes were produced and compared: fast-degrading (FD-SAPAE) and slow-degrading (SD-SAPAE) membranes that release salicylic acid at a faster and slower rate, respectively. Rat femur defects were treated with BMP-2 and wrapped with FD-SAPAE, SD-SAPAE, or PCL membrane or were left unwrapped. The effects of different membranes on bone formation within and outside of the femur defects were measured by histomorphometry and microcomputed tomography. Bone formation within the defect was not affected by membrane wrapping at BMP-2 doses of 12 μg or more. In contrast, the FD-SAPAE membrane significantly reduced bone formation outside the defect compared with all other treatments. The rapid release of salicylic acid from the FD-SAPAE membrane suggests that localized salicylic acid treatment during the first few days of BMP-2 treatment can limit ectopic bone formation. The data support development of SAPAE polymer membranes for guided bone regeneration applications as well as barriers to excessive bone formation.

  15. Evaluation of Biomaterials Using Micro-Computerized Tomography

    Science.gov (United States)

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

    2008-09-01

    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.

  16. BREEDER: a microcomputer program for financial analysis of a large-scale prototype breeder reactor

    Energy Technology Data Exchange (ETDEWEB)

    Giese, R.F.

    1984-04-01

    This report describes a microcomputer-based, single-project financial analysis program: BREEDER. BREEDER is a user-friendly model designed to facilitate frequent and rapid analyses of the financial implications associated with alternative design and financing strategies for electric generating plants and large-scale prototype breeder (LSPB) reactors in particular. The model has proved to be a useful tool in establishing cost goals for LSPB reactors. The program is available on floppy disks for use on an IBM personal computer (or IBM look-a-like) running under PC-DOS or a Kaypro II transportable computer running under CP/M (and many other CP/M machines). The report documents version 1.5 of BREEDER and contains a user's guide. The report also includes a general overview of BREEDER, a summary of hardware requirements, a definition of all required program inputs, a description of all algorithms used in performing the construction-period and operation-period analyses, and a summary of all available reports. The appendixes contain a complete source-code listing, a cross-reference table, a sample interactive session, several sample runs, and additional documentation of the net-equity program option.

  17. Factor analysis and predictive validity of microcomputer-based tests

    Science.gov (United States)

    Kennedy, R. S.; Baltzley, D. R.; Turnage, J. J.; Jones, M. B.

    1989-01-01

    11 tests were selected from two microcomputer-based performance test batteries because previously these tests exhibited rapid stability (less than 10 min, of practice) and high retest reliability efficiencies (r greater than 0.707 for each 3 min. of testing). The battery was administered three times to each of 108 college students (48 men and 60 women) and a factor analysis was performed. Two of the three identified factors appear to be related to information processing ("encoding" and "throughput/decoding"), and the third named an "output/speed" factor. The spatial, memory, and verbal tests loaded on the "encoding" factor and included Grammatical Reasoning, Pattern Comparison, Continuous Recall, and Matrix Rotation. The "throughput/decoding" tests included perceptual/numerical tests like Math Processing, Code Substitution, and Pattern Comparison. The output speed factor was identified by Tapping and Reaction Time tests. The Wonderlic Personnel Test was group administered before the first and after the last administration of the performance tests. The multiple Rs in the total sample between combined Wonderlic as a criterion and less than 5 min. of microcomputer testing on Grammatical Reasoning and Math Processing as predictors ranged between 0.41 and 0.52 on the three test administrations. Based on these results, the authors recommend a core battery which, if time permits, would consist of two tests from each factor. Such a battery is now known to permit stable, reliable, and efficient assessment.

  18. Analysis of fault using microcomputer protection by symmetrical component method

    Directory of Open Access Journals (Sweden)

    Mr. Ashish Choubey

    2012-09-01

    Full Text Available To enhance power supply reliability for the userterminals in the case of the distribution system toavoid interference by the fault again, rapidlycomplete the automatic identification, positioning,automatic fault isolation, network reconfigurationuntil the resumption of supply of non-fault section,a microprocessor-based relay protection device hasdeveloped. As the fault component theory is widelyused in microcomputer protection, and faultcomponent exists in the network of faultcomponent, it is necessary to build up the faultcomponent network when short circuit faultemerging and to draw the current and voltagecomponent phasor diagram at fault point. In orderto understand microcomputer protection based onthe symmetrical component principle, we obtainedthe sequence current and sequence voltageaccording to the concept of symmetrical component.Distribution line directly to user-oriented powersupply, the reliability of its operation determines thequality and level of electricity supply. In recentdecades, because of the general power of the tirelessefforts of scientists and technicians, relay protectiontechnology and equipment application level hasbeen greatly improved, but the current domesticproduction of computer hardware, protectiondevices are still outdated systems. Softwaredevelopment has maintenance difficulties and shortsurvival time. With the factory automation systeminterface functions weak points, the networkcommunication cannot meet the actualrequirements. Protection principle configurationand device manufacturing process to be improvedand so on.

  19. Analysis of fault using microcomputer protection by symmetrical component method

    Directory of Open Access Journals (Sweden)

    Ashish Choubey

    2012-09-01

    Full Text Available To enhance power supply reliability for the user terminals in the case of the distribution system to avoid interference by the fault again, rapidly complete the automatic identification, positioning, automatic fault isolation, network reconfiguration until the resumption of supply of non-fault section, a microprocessor-based relay protection device has developed. As the fault component theory is widely used in microcomputer protection, and fault component exists in the network of fault component, it is necessary to build up the fault component network when short circuit fault emerging and to draw the current and voltage component phasor diagram at fault point. In order to understand microcomputer protection based on the symmetrical component principle, we obtained the sequence current and sequence voltage according to the concept of symmetrical component. Distribution line directly to user-oriented power supply, the reliability of its operation determines the quality and level of electricity supply. In recent decades, because of the general power of the tireless efforts of scientists and technicians, relay protection technology and equipment application level has been greatly improved, but the current domestic production of computer hardware, protection devices are still outdated systems. Software development has maintenance difficulties and short survival time. With the factory automation system interface functions weak points, the network communication cannot meet the actual requirements. Protection principle configuration and device manufacturing process to be improved and so on.

  20. Computed Tomography Guided Hook-wire Precise Localization and Minimally Invasive Resection of Pulmonary Nodules%CT引导下Hook-w ire精确定位并微创切除肺结节

    Institute of Scientific and Technical Information of China (English)

    王通; 马少华; 闫天生; 宋金涛; 王可毅; 贺未; 白洁

    2015-01-01

    ,积极微创手术治疗是非常必要的。%Background and objective Localization of pulmonary ground glass nodule is the technical diffculty of minimally invasive operation resection. hTe aim of this study is to evaluate the value of computed tomography (CT)-guided Hook-wire precise localization in resection of pulmonary nodules by video-assisted thoracoscopic surgery (VATS) as well as to discuss the necessity and feasibility of surgical resection of GGOs through a minimally invasive approach.Methods CT-guided Hook-wire precise localization and wedge resection was done on 25 cases with 26 pulmonary nodules by VATS from May 2013 to June 2015. hTe effcacy of localization was evaluated in terms of procedure time, VATS success rate, and associated complications of localization.Results All the 26 pulmonary nodules (6 solid nodules and 20 GGOs ) of 25 patients (10 males and 15 females) were preoperatively detected and localized with Hook-wire under CT guidance. Nodule diameters ranged from 5 mm-20 mm (mean: 8 mm). hTe distance of lung lesions from the nearest pleural surfaces ranged within 5 mm-30 mm (mean: 14 mm). All resections of lesions guided by the Hook-wire were successfully performed by VATS (success rate: 100%). hTe mean procedure time for the CT-guided Hook-wire localization was 10 min (range: 5 min-10 min). hTe mean procedure time for VATS wedge resection was 20 min (range: 15 min-40 min). hTe mean hospital time was 4 d (range: 3 d-6 d). hTe major complication of CT-guided Hook-wire localization was mild pneumothorax in 4 patients, but no one needed chest tube drain-age. Wedge resection was performed successfully in all cases. hTe dislocation of Hook-wire was found in only one patient dur-ing the operation, but the lesion was still successfully resected under VATS. Results of pathological examination of 16 mGGOs revealed 8 primary lung cancers and 8 nonspeciifc chronic inlfammations. Results of pathological examination of 4 pGGOs re-vealed 1 primary lung cancers, 1 atypical

  1. Visualization of self-healing materials by X-ray computed micro-tomography at UGCT

    OpenAIRE

    Bultreys, Tom; Masschaele, Bert; Hillewaere, Xander; Dierick, Manuel; Van Loo, Denis; Van Hoorebeke, Luc; Cnudde, Veerle

    2013-01-01

    This work presents recent advancements in X-ray micro-computed tomography (XRMCT) of self-healing materials at Ghent University’s Centre for X-ray Tomography (UGCT). Results of XRMCT imaging in a self-healing polymer system are shown to demonstrate the use of XRMCT in self-healing studies. Furthermore, two new XRMCT scanners are presented. The HECTOR scanner was designed for large samples and strongly attenuating samples, and is therefore well suited to study self-healing concrete. The EMCT s...

  2. WE-G-207-03: Mask Guided Image Reconstruction (MGIR): A Novel Method for Ultra-Low-Dose 3D and Enhanced 4D Cone-Beam Computer-Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Park, C; Zhang, H; Chen, Y; Fan, Q; Kahler, D; Li, J; Liu, C; Lu, B [Univ Florida, Gainesville, FL (United States)

    2015-06-15

    Purpose: Recently, compressed sensing (CS) based iterative reconstruction (IR) method is receiving attentions to reconstruct high quality cone beam computed tomography (CBCT) images using sparsely sampled or noisy projections. The aim of this study is to develop a novel baseline algorithm called Mask Guided Image Reconstruction (MGIR), which can provide superior image quality for both low-dose 3DCBCT and 4DCBCT under single mathematical framework. Methods: In MGIR, the unknown CBCT volume was mathematically modeled as a combination of two regions where anatomical structures are 1) within the priori-defined mask and 2) outside the mask. Then we update each part of images alternatively thorough solving minimization problems based on CS type IR. For low-dose 3DCBCT, the former region is defined as the anatomically complex region where it is focused to preserve edge information while latter region is defined as contrast uniform, and hence aggressively updated to remove noise/artifact. In 4DCBCT, the regions are separated as the common static part and moving part. Then, static volume and moving volumes were updated with global and phase sorted projection respectively, to optimize the image quality of both moving and static part simultaneously. Results: Examination of MGIR algorithm showed that high quality of both low-dose 3DCBCT and 4DCBCT images can be reconstructed without compromising the image resolution and imaging dose or scanning time respectively. For low-dose 3DCBCT, a clinical viable and high resolution head-and-neck image can be obtained while cutting the dose by 83%. In 4DCBCT, excellent quality 4DCBCT images could be reconstructed while requiring no more projection data and imaging dose than a typical clinical 3DCBCT scan. Conclusion: The results shown that the image quality of MGIR was superior compared to other published CS based IR algorithms for both 4DCBCT and low-dose 3DCBCT. This makes our MGIR algorithm potentially useful in various on

  3. Microcomputer controlled X-ray diffractometer for investigations in transmission technique

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, E.C.; Kroeber, R.; Wessel, R.; Mueller, J.J.; Gernat, C.; Pleissner, K.P.; Damaschun, G.; Lucius, H. (Akademie der Wissenschaften der DDR, Berlin. Zentralinstitut fuer Molekularbiologie)

    1984-01-01

    The coupling of the microcomputer system MPS 4944 with an X-ray wide-angle diffractometer is presented. The configuration of the system, algorithms and programs are described. The microcomputer system effects control and surveillance of the goniometer, accumulation and normalization of the scattered intensities. The coupling of a microcomputer to the diffractometer afforded an increase of the precision of measurement, shortening of the time needed for the scattering experiment and improved the handling comfort of the diffractometer. New experimental variants are rendered possible, for instance, structural investigations with program-controlled temperature regulation of the samples.

  4. Nanoparticle-guided radiotherapy

    DEFF Research Database (Denmark)

    2012-01-01

    The present invention relates to a method and nano-sized particles for image guided radiotherapy (IGRT) of a target tissue. More specifically, the invention relates to nano-sized particles comprising X-ray-imaging contrast agents in solid form with the ability to block x-rays, allowing for simult...... for simultaneous or integrated external beam radiotherapy and imaging, e.g., using computed tomography (CT)....

  5. A new microcomputer-based ECG analysis system.

    Science.gov (United States)

    Kyle, M C; Klingeman, J D; Conrad, J D; Freis, E D; Pipberger, H V

    1983-09-01

    A new automated ECG system using advances in microprocessor technology and computerized electrocardiography is described. This microcomputer-based system is self-contained and mobile. It acquires both the 12-lead and orthogonal lead (Frank) electrocardiograms and analyzes the latter within minutes. Software includes the program developed in the Veterans Administration which uses advanced statistical classification techniques and a large well-documented patient data base. Diagnostic probabilities are computed using a Bayesian approach. Diagnostic performance has been tested using independent clinical criteria and found to be quite accurate. This system enables the clinician to immediately review the computer's identifications, measurements, and diagnostic classifications and quickly use these results in clinical decision making. Serial comparisons are readily made since all previous recordings are stored on floppy diskettes. The use of microprocessors in this system makes it economically feasible for practicing physicians.

  6. Microcomputer based instrument for measuring a novel pulmonary function test

    Science.gov (United States)

    Craine, Brian L.; Craine, Eric R.

    1996-08-01

    The design of a prototype instrument for measuring the end-tidal concentration of carbon monoxide during human respiration is presented. The instrument automatically samples the final sixty cubic centimeters of exhaled breath, from successive breathing cycles, by coordinating a pump and the breathing cycle with a set of vacuum and pressure sensors. The concentration of carbon monoxide is measured using a nondispersive infrared spectrophotometer. The amount of carbon monoxide present is measured relative to the source air concentration eliminating the need for calibrating the instrument. The testing protocol and measurements can be controlled by a microcomputer connected to the instrument through a standard RS-232 serial interface. When at equilibrium, the end-tidal concentration of CO can be measured in a simple and reproducible fashion. This simplified technology allows for the construction of a small, portable, easy to use instrument that will allow the application of this new pulmonary function test at the point of contact with patients.

  7. Development of a microcomputer-based magnetic heading sensor

    Science.gov (United States)

    Garner, H. D.

    1987-01-01

    This paper explores the development of a flux-gate magnetic heading reference using a single-chip microcomputer to process heading information and to present it to the pilot in appropriate form. This instrument is intended to replace the conventional combination of mechanical compass and directional gyroscope currently in use in general aviation aircraft, at appreciable savings in cost and reduction in maintenance. Design of the sensing element, the signal processing electronics, and the computer algorithms which calculate the magnetic heading of the aircraft from the magnetometer data have been integrated in such a way as to minimize hardware requirements and simplify calibration procedures. Damping and deviation errors are avoided by the inherent design of the device, and a technique for compensating for northerly-turning-error is described.

  8. An advanced microcomputer design for processing of semiconductor materials

    Science.gov (United States)

    Bjoern, L.; Lindkvist, L.; Zaar, J.

    1988-01-01

    In the Get Away Special 330 payload two germanium samples doped with gallium will be processed. The aim of the experiments is to create a planar solid/liquid interface, and to study the breakdown of this interface as the crystal growth rate increases. For the experiments a gradient furnace was designed which is heated by resistive heaters. Cooling is provided by circulating gas from the atmosphere in the cannister through cooling channels in the furnace. The temperature along the sample are measured by platinum/rhodium thermocouples. The furnace is controlled by a microcomputer system, based upon the processor 80C88. A data acquisition system is integrated into the system. In order to synchronize the different actions in time, a multitask manager is used.

  9. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... Professions Site Index A-Z Computed Tomography (CT) - Head Computed tomography (CT) of the head uses special ... the Head? What is CT Scanning of the Head? Computed tomography, more commonly known as a CT ...

  10. Continuing Education in Micro-Computers for Academic and Practicing Psychologists.

    Science.gov (United States)

    Lupo, James V.; Ware, Mark E.

    1984-01-01

    A workshop designed to teach participants how to use microcomputers for practice management, psychological testing, word processing, peripheral interface, and data analysis was found to meet the interests and needs of both academic and practicing psychologists. (RM)

  11. Microcomputer design and analysis of the cable catenary large space antenna system

    Science.gov (United States)

    Akle, W.

    1984-01-01

    The use of microcomputers in the design of a cable catenary large space antenna system is discussed. The development of a system design capability, data base utilization, systems integration, program structure and logic, and integrated graphics output are discussed.

  12. Assessing Inexpensive Microcomputers for Classroom Use: A Product-Oriented Course to Promote Instructional Computing Literacy.

    Science.gov (United States)

    Ricketts, Dick; Seay, Jean A.

    1979-01-01

    A teacher inservice class that focused on evaluating inexpensive microcomputer systems is described. Evaluative criteria used by the class are included, and the findings and preferences of the class are summarized. (Author/IRT)

  13. Digital TV-echelle spectrograph for simultaneous multielemental analysis using microcomputer control

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, J.B.; Case, A.L.

    1980-12-01

    A digital TV-echelle spectrograph with microcomputer control was developed for simultaneous multielemental analysis. The optical system is a commercially available unit originally equipped for film and photomultiplier (single element) readout. The film port was adapted for the intensifier camera. The camera output is digitized and stored in a microcomputer-controlled, 512 x 512 x 12 bit memory and image processor. Multiple spectra over the range of 200 to 800 nm are recorded in a single exposure. Spectra lasting from nanoseconds to seconds are digitized and stored in 0.033 s and displayed on a TV monitor. An inexpensive microcomputer controls the exposure, reads and displays the intensity of predetermined spectral lines, and calculates wavelengths of unknown lines. The digital addresses of unknown lines are determined by superimposing a cursor on the TV display. The microcomputer also writes into memory wavelength fiducial marks for alignment of the TV camera.

  14. Microcomputer Decisions for the 1990s [and] Apple's Macintosh: A Viable Choice.

    Science.gov (United States)

    Grosch, Audrey N.

    1989-01-01

    Discussion of the factors that should be considered when purchasing or upgrading a microcomputer focuses on the MS-DOS and OS/2 operating systems. Macintosh purchasing decisions are discussed in a sidebar. A glossary is provided. (CLB)

  15. Periodic precipitation a microcomputer analysis of transport and reaction processes in diffusion media, with software development

    CERN Document Server

    Henisch, H K

    1991-01-01

    Containing illustrations, worked examples, graphs and tables, this book deals with periodic precipitation (also known as Liesegang Ring formation) in terms of mathematical models and their logical consequences, and is entirely concerned with microcomputer analysis and software development. Three distinctive periodic precipitation mechanisms are included: binary diffusion-reaction; solubility modulation, and competitive particle growth. The book provides didactic illustrations of a valuable investigational procedure, in the form of hypothetical experimentation by microcomputer. The development

  16. Direct microcomputer controlled determination of zinc in human serum by flow injection atomic absorption spectrometry

    DEFF Research Database (Denmark)

    Simonsen, Kirsten Wiese; Nielsen, Bent; Jensen, Arne

    1986-01-01

    A procedure is described for the direct determination of zinc in human serum by fully automated, microcomputer controlled flow injection atomic absorption spectrometry (Fl-AAS). The Fl system is pumpless, using the negative pressure created by the nebuliser. It only consists of a three-way valve......, programmable from the microcomputer, to control the sample volume. No pre-treatment of the samples is necessary. The limit of detection is 0.14 mg l–1, and only small amounts of serum (

  17. Noninvasive Spatiotemporal Profiling of the Processes of Impregnation and Drying within Mo/Al2O3 Catalyst Bodies by a Combination of X-ray Absorption Tomography and Diagonal Offset Raman Spectroscopy

    NARCIS (Netherlands)

    Gibson, E.K.; Zandbergen, M.W.; Jacques, S.D.M.; Biao, C.; Cernik, R.J.; O’Brien, M.G.; Di Michiel, M.; Weckhuysen, B.M.; Beale, A.M.

    2013-01-01

    A combination of X-ray absorption microcomputed tomography (μ-CT) and diagonal offset raman spectroscopy (DORS) have been used to follow in real time the 2-D and 3-D evolution of Mo species within 3 mm γ-Al2O3 extrudates during catalyst impregnation and drying processes. In a first set of experiment

  18. 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.

  19. Neutron tomography

    Science.gov (United States)

    Crump, James C., III; Richards, Wade J.; Shields, Kevin C.

    1995-07-01

    The McClellan Nuclear Radiation Center's (MNRC) staff in conjunction with a Cooperative Research and Development Agreement (CRDA) with the U.C. Santa Barbara facility has developed a system that can be used for aircraft inspection of jet engine blades. The problem was to develop an inspection system that can detect very low concentrations of hydrogen (i.e., greater than 100 ppm) in metal matricies. Specifically in Titanium alloy jet engine blades. Entrapment and precipitation of hydrogen in metals is an undesirable phenomenon which occurs in many alloys of steel and titanium. In general, metals suffer a loss of mechanical properties after long exposures to hydrogen, especially at high temperatures and pressures, thereby becoming embrittled. Neutron radiography has been used as a nondestructive testing technique for many years. Neutrons, because of their unique interactions with materials, are especially useful in the detection of hydrogen. They have an extremely high interaction cross section for low atomic number nuclei (i.e., hydrogen). Thus hydrogen in a metal matrix can be visualized using neutrons. Traditional radiography is sensitive to the total attenuation integrated over the path of radiation through the material. Increased sensitivity and quantitative cross section resolution can be obtained using three-dimensional volumetric imaging techniques such as tomography. The solution used to solve the problem was to develop a neutron tomography system. The neutron source is the McClellan Nuclear Radiation Center's 1 MW TRIGA reactor. This paper describes the hardware used in the system as well as some of the preliminary results.

  20. Long - term Efficacy of Computed Tomography - guided Percutaneous Radiofrequency Thermocoagulation for Glossopharyngeal Neuralgia%CT 引导下射频热凝术治疗舌咽神经痛的长期疗效分析

    Institute of Scientific and Technical Information of China (English)

    王小平; 左欣鹭; 曾塬杰; 倪家骧

    2016-01-01

    Objective To observe the long - term efficacy and adverse reactions of computed tomography( CT) -guided percutaneous radiofrequency thermocoagulation(PRT)in the treatment of glossopharyngeal neuralgia(GPN). Methods The study enrolled 80 GNP patients who received treatment and underwent CT - guided PRT in the Department of Pain Management,Xuanwu Hospital Capital Medical University from January 2003 to December 2014. The status of pain remission of the patients after surgery was observed,and pain relief rates and adverse reactions(including paresthesia in the root of tongue and pharynx,dysphagia,decreased gag reflex,cranial nerve damage and death )were recorded 3 months,6 months,1 year,3 years,5 years and 10 years after surgery. Results Among the 80 patients,63 (78. 8% ) had pain relief,and other 17 (21. 2% )had decrease in pain and used antiepileptic drug to control pain. The 3 months,6 months,1 year,3 years,5 years and 10 years relief rates were 77. 5% ,75. 0% ,73. 2% ,63. 0% ,53. 2% and 43. 0% respectively. Paresthesia in the root of tongue and pharynx occurred in 11(13. 8% )patients,among which 8 patients saw the paresthesia disappear(25. 3 ± 12. 6) weeks later and the rest 3 patients saw the paresthesia persistently exist but have slight influence on life. Dysphagia occurred in 5 (6. 3% )patients and decreased gag reflex occurred in 2(2. 5% )patients. The above two symptoms disappeared 2 weeks after surgery. No patients had cranial nerve damage or death. Conclusion CT - guided PRT provides favorable long - term efficacy in the treatment of GPN and causes no serious adverse reactions,which is worth clinical application.%目的:观察 CT 引导下射频热凝术治疗舌咽神经痛(GPN)的长期疗效和不良反应。方法选取2003年1月—2014年12月于首都医科大学宣武医院疼痛科就诊的行 CT 引导下射频热凝术的 GPN 患者80例,观察患者术后疼痛缓解情况及术后3个月、6个月、1年、3年、5年、10年疼痛

  1. Magnetic Particle / Magnetic Resonance Imaging: In-Vitro MPI-Guided Real Time Catheter Tracking and 4D Angioplasty Using a Road Map and Blood Pool Tracer Approach.

    Directory of Open Access Journals (Sweden)

    Johannes Salamon

    Full Text Available In-vitro evaluation of the feasibility of 4D real time tracking of endovascular devices and stenosis treatment with a magnetic particle imaging (MPI / magnetic resonance imaging (MRI road map approach and an MPI-guided approach using a blood pool tracer.A guide wire and angioplasty-catheter were labeled with a thin layer of magnetic lacquer. For real time MPI a custom made software framework was developed. A stenotic vessel phantom filled with saline or superparamagnetic iron oxide nanoparticles (MM4 was equipped with bimodal fiducial markers for co-registration in preclinical 7T MRI and MPI. In-vitro angioplasty was performed inflating the balloon with saline or MM4. MPI data were acquired using a field of view of 37.3×37.3×18.6 mm3 and a frame rate of 46 volumes/sec. Analysis of the magnetic lacquer-marks on the devices were performed with electron microscopy, atomic absorption spectrometry and micro-computed tomography.Magnetic marks allowed for MPI/MRI guidance of interventional devices. Bimodal fiducial markers enable MPI/MRI image fusion for MRI based roadmapping. MRI roadmapping and the blood pool tracer approach facilitate MPI real time monitoring of in-vitro angioplasty. Successful angioplasty was verified with MPI and MRI. Magnetic marks consist of micrometer sized ferromagnetic plates mainly composed of iron and iron oxide.4D real time MP imaging, tracking and guiding of endovascular instruments and in-vitro angioplasty is feasible. In addition to an approach that requires a blood pool tracer, MRI based roadmapping might emerge as a promising tool for radiation free 4D MPI-guided interventions.

  2. Surgical and orthodontic management of maxillary palatal impacted canines guided by cone-beam compu-ted tomography%上颌腭侧埋伏阻生尖牙 CBCT 导引下的牵引治疗

    Institute of Scientific and Technical Information of China (English)

    于剑南; 王林; 王震东; 邵胜; 李媛; 赵春洋

    2015-01-01

    目的:探讨锥形束 CT(CBCT)三维(3D)重建在上颌腭侧埋伏阻生尖牙牵引治疗中的指导作用。方法:对22例上颌尖牙(共26颗)腭侧埋伏阻生的青少年患者行 CBCT 检查。CBCT 三维重建观察尖牙形态、腭侧埋伏状况,测量分析与邻近组织的位置关系及相邻切牙牙根吸收情况。结果:CBCT 能够真实再现颌骨内埋伏的上颌尖牙。埋伏尖牙均近中倾斜,与平面平均成角61.1°±18.1°,近中异位分别为Ⅰ类埋伏尖牙8颗、Ⅱ类5颗、Ⅲ类3颗、Ⅳ类10颗。3颗相邻侧切牙及2颗中切牙因严重牙根吸收而拔除;26颗上颌腭侧埋伏尖牙均成功牵引至平面排入牙弓并建立正常咬合。结论:CBCT 能立体再现上颌尖牙腭侧埋伏阻生特征及与邻近牙的关系等,对治疗方案的制定、开窗牵引具有指导作用,可提高疗效。%Objective:To assess the guidance of 3D reconstruction in the surgical and orthodontic management of maxillary palatal impacted canines with cone-beam computed tomography (CBCT).Methods:22 adolescent patients with 26 impacted maxillary conines were examined by CBCT.CBCT 3D reconstruction was used to observe the impaction of the canines.Measurements were taken to evaluate spatial relationship between the canine and adjacent structures and resorption of neighboring incisor roots.Results:CBCT was effective to localize the impacted canines.All of the maxillary palatal impacted canines inclinated mesially,angles of impacted ca-nines to occlusal plane were 61.1°±18.1°,there were 8,5,3 and 10 impacted canines found in classⅠ,Ⅱ,Ⅲ and Ⅳ mesial mal-position respectively.3 adjacent lateral incisors and 2 central incisors were extracted because of severely root resorption.Normal occlu-sion was achieved for 26 impacted canines by the traction of the canines into dental arch and reaching the occlusal plane.Conclusion:CBCT can spatially show the palatal impaction of maxillary

  3. Restrain of bone growth by estrogen-mimetic peptide-1 (EMP-1): a micro-computed tomographic study.

    Science.gov (United States)

    Kasher, Roni; Bajayo, Alon; Gabet, Yankel; Nevo, Nava; Fridkin, Mati; Katchalski-Katzir, Ephraim; Kohen, Fortune; Bab, Itai

    2009-06-01

    Estrogen has a key role in the regulation of skeletal growth and maintenance of bone mass. Recently, we developed peptides having estrogen-like activity as potential estrogen-based new drugs. The aim of the present study was to evaluate the influence of long-term administration of the most efficacious of these peptides, the hexapeptide EMP-1 (VSWFFE), on bone mass and development. EMP-1 was injected daily to ovariectomized (OVX) and intact young, sexually mature female mice for 10 weeks. Whole femora, including the cartilaginous growth plates were analyzed by micro-computed tomography (microCT). We found that peptide EMP-1 restrains bone growth in OVX mice: it inhibited dramatically bone longitudinal growth (40%), and decreased femoral diaphyseal diameter. Peptide EMP-1 had no effect on bone growth in normal mice, and did not influence the OVX-induced bone loss. We then developed a new microCT methodology to evaluate uncalcified and calcified growth plate parameters. In the OVX mice, peptide EMP-1 reduced volume and thickness of the uncalcified growth plate, a possible cause for the inhibition of bone longitudinal growth. Peptide EMP-1 may be used as a lead compound for the development of drugs to treat acromegalic patients.

  4. The FORTRAN NALAP code adapted to a microcomputer compiler

    Energy Technology Data Exchange (ETDEWEB)

    Lobo, Paulo David de Castro; Borges, Eduardo Madeira; Braz Filho, Francisco Antonio; Guimaraes, Lamartine Nogueira Frutuoso, E-mail: plobo.a@uol.com.b, E-mail: eduardo@ieav.cta.b, E-mail: fbraz@ieav.cta.b, E-mail: guimarae@ieav.cta.b [Instituto de Estudos Avancados (IEAv/CTA), Sao Jose dos Campos, SP (Brazil)

    2010-07-01

    The Nuclear Energy Division of the Institute for Advanced Studies (IEAv) is conducting the TERRA project (TEcnologia de Reatores Rapidos Avancados), Technology for Advanced Fast Reactors project, aimed at a space reactor application. In this work, to attend the TERRA project, the NALAP code adapted to a microcomputer compiler called Compaq Visual Fortran (Version 6.6) is presented. This code, adapted from the light water reactor transient code RELAP 3B, simulates thermal-hydraulic responses for sodium cooled fast reactors. The strategy to run the code in a PC was divided in some steps mainly to remove unnecessary routines, to eliminate old statements, to introduce new ones and also to include extension precision mode. The source program was able to solve three sample cases under conditions of protected transients suggested in literature: the normal reactor shutdown, with a delay of 200 ms to start the control rod movement and a delay of 500 ms to stop the pumps; reactor scram after transient of loss of flow; and transients protected from overpower. Comparisons were made with results from the time when the NALAP code was acquired by the IEAv, back in the 80's. All the responses for these three simulations reproduced the calculations performed with the CDC compiler in 1985. Further modifications will include the usage of gas as coolant for the nuclear reactor to allow a Closed Brayton Cycle Loop - CBCL - to be used as a heat/electric converter. (author)

  5. Long term stability of rat sleep quantified by microcomputer analysis.

    Science.gov (United States)

    Vivaldi, E A; Pastel, R H; Fernstrom, J D; Hobson, J A

    1984-09-01

    An inexpensive microcomputer system is described for the direct recording of electrographic data from animals. Using this system, electrographic data can be recorded continuously on a polygraph and simultaneously quantitated by the computer, for days or weeks. Our system quantifies the amounts of delta waves, spindle bursts, hippocampal RSA activity and movement spikes for 15 sec epochs. These electrographic data are stored by the computer and subsequently can be used to score sleep stages. We find that the computer reliably counts waves; using these data, it can then score sleep stages off-line with about 90% accuracy. With this system, we find that the minutes/hour of both SWS and REM are remarkably stable from day to day. The absolute number of delta waves, spindle bursts, trains of RSA and movement counts/hour also remain stable from day to day. This type of system should find significant application in situations where quantitation of longterm effects of drugs, diets and other environmental inputs on sleep states or EEG wave bands are of interest.

  6. Comparison of fast-acting of Java on microcomputer Raspberry Pi

    Directory of Open Access Journals (Sweden)

    O. I. Didukh

    2015-03-01

    Full Text Available Introduction. The speed of a specific set of instructions is important working with highlevel programming language for microcomputers. The method of comparing execution times of two functionally different programs on different versions of Virtual Machine Java is used to determine the performance of Java on Raspberry Pi microcomputer. Application of modern fast search algorithm primes up to a given integer N (Atkin sieve and a program to perform basic operations on floating point numbers are implemented. Results. Two algorithms microcomputer operating frequencies: 700 MHz, 900 MHz, 1000 MHz are tested. Two versions of Java for Raspberry Pi: Oracle Java and OpenJDK are used. Conclusions. In microcomputer Raspberry Pi elementary operations on floating-point run are faster than with complex search algorithm primes. It is established that Java from Oracle is 13-14 times is faster than OpenJDK. Oracle Java on Raspberry Pi gives good performance and it is recommended for installation and use on microcomputer.

  7. Microcomputers and minipopulations: the 1981 Cook Islands census.

    Science.gov (United States)

    Hayes, G R

    1983-01-01

    This paper presents some of the background behind the installation and use of a microcomputer for census processing and briefly reviews the results of the 1981 census in the light of the Cook Islands' special demographic situation. Since independence from New Zealand in 1965, the Cook Islands has gradually developed a capacity for statistics gathering in general and census taking in particular. The 1981 quinquennial census represents a watershed in the development of local personnel without the aid of external advisors; it was the 1st census to be processed within the Cook Islands by means of a computer. Both the installation of the microcomputer and the processing of the 1981 census are counted as successes. This is due to a number of factors, namely: a long period of careful planning procedures which preceded the choice of system and installation; the enthusiasm of the local staff closely involved in the planning; the emphasis on training; tests of the equipment before installation by computer practitioners with knowledge of local needs and capacities; reasonable goal setting; and the supply, with the system, of adequate spare parts tools and maintenance and training manuals. Like many island populations, that of the Cook Islands is characterized by considerable instability as illustrated by the 1981 census results. As the rate and direction of population change varies from island to island, generalizations across the nation as a whole are difficult. For example, while some of the northern atolls experienced population decline during the latest intercensal period, most had their popultion increase in 1981. All the southern islands declined during the 1976-81 period at annual rates varying from 0.6% to 3.2%. The explanation for these patterns of change lies primarily in the different rates and direction of external migration on each island, as Cook Islanders are exempt from immigration regulations to New Zealand and Australia. In recent years, women have formed a

  8. A microcomputer-controlled gas phase microreactor system

    Energy Technology Data Exchange (ETDEWEB)

    Morris, R.M.

    1983-08-01

    Although automated reactors are effective tools for studying a single type of reaction or optimizing catalyst performance, they may not be well suited for exploratory research. These reactors generally have several shortcomings. First, they may have limited versatility since they are usually designed with a single application in mind. Second, computer systems used for process control and data acquisition are often expensive and complex, so that once they are set up for a given application, it is quite difficult to adapt them for another. Because of these restrictions, experimental reactors are often operated manually, requiring a full-time operator to monitor operations and acquire data. This is a greater problem in laboratories where projects are often short-term, and the costs of setting up an automated reactor may outweigh the benefits of automation. For an automated reactor to be cost-effective in such an environment, both reactor hardware and control software must be versatile enough that they can be easily modified and adapted for different experiments. An automated gas-flow microreactor has been designed and constructed which is both inexpensive and flexible. The reactor is capable of performing three different types of experiments, 1) continuous reagent feed with analysis of the product stream, 2) pulsed-flow experiments, and 3) temperature-programmed desorption (TPD) and reaction (TPR). Conversion of the reactor from one configuration to another requires less than one hour. Process control and data acquisition are performed using an Apple II Plus microcomputer (Apple Computer Corp., Cupertino, Calif.) and an ISAAC interface device (Cyborg Corp., Newton, Mass.).

  9. 48 CFR 1552.239-103 - Acquisition of Energy Star Compliant Microcomputers, Including Personal Computers, Monitors and...

    Science.gov (United States)

    2010-10-01

    ... Compliant Microcomputers, Including Personal Computers, Monitors and Printers. 1552.239-103 Section 1552.239... Star Compliant Microcomputers, Including Personal Computers, Monitors and Printers. As prescribed in... Personal Computers, Monitors, and Printers (APR 1996) (a) The Contractor shall provide computer products...

  10. "Hack" Is Not A Dirty Word--The Tenth Anniversary of Patron Access Microcomputer Centers in Libraries.

    Science.gov (United States)

    Dewey, Patrick R.

    1986-01-01

    The history of patron access microcomputers in libraries is described as carrying on a tradition that information and computer power should be shared. Questions that all types of libraries need to ask in planning microcomputer centers are considered and several model centers are described. (EM)

  11. "Hack" Is Not A Dirty Word--The Tenth Anniversary of Patron Access Microcomputer Centers in Libraries.

    Science.gov (United States)

    Dewey, Patrick R.

    1986-01-01

    The history of patron access microcomputers in libraries is described as carrying on a tradition that information and computer power should be shared. Questions that all types of libraries need to ask in planning microcomputer centers are considered and several model centers are described. (EM)

  12. Effects of industrial microcomputer use in control systems for machines and conveyors in surface mining

    Energy Technology Data Exchange (ETDEWEB)

    Borczyk, Z.; Rosseger, A. (Poltegor-Instytut, Wroclaw (Poland))

    1991-01-01

    Evaluates use of the ComPan Pzaz microcomputers manufactured in Poland for control of bucket wheel excavators without thrust action and for belt conveyors used in brown coal surface mines in Poland. The microcomputer consists of 14 standard microprocessor controller modules and 4 specialized modules. Structure of the control system, types of operations controlled by the system and effects of computerized control on safety and efficiency of operation of bucket wheel excavators are analyzed. Use of the ComPan Pzaz microcomputers for control of steep-angle conveyor systems (with a drive power from 1,000 kW to 4,000 kW) is evaluated. The system controls conveyor start-up and conveyor braking. Selected aspects of ComPan Pzaz reliability and service are also discussed. 2 refs.

  13. Application of a microcomputer-based system to control and monitor bacterial growth.

    Science.gov (United States)

    Titus, J A; Luli, G W; Dekleva, M L; Strohl, W R

    1984-02-01

    A modular microcomputer-based system was developed to control and monitor various modes of bacterial growth. The control system was composed of an Apple II Plus microcomputer with 64-kilobyte random-access memory; a Cyborg ISAAC model 91A multichannel analog-to-digital and digital-to-analog converter; paired MRR-1 pH, pO(2), and foam control units; and in-house-designed relay, servo control, and turbidimetry systems. To demonstrate the flexibility of the system, we grew bacteria under various computer-controlled and monitored modes of growth, including batch, turbidostat, and chemostat systems. The Apple-ISAAC system was programmed in Labsoft BASIC (extended Applesoft) with an average control program using ca. 6 to 8 kilobytes of memory and up to 30 kilobytes for datum arrays. This modular microcomputer-based control system was easily coupled to laboratory scale fermentors for a variety of fermentations.

  14. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... the Sinuses? What is CT (Computed Tomography) of the Sinuses? Computed tomography, more commonly known as a ... of page What are some common uses of the procedure? CT of the sinuses is primarily used ...

  15. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... the limitations of CT of the Sinuses? What is CT (Computed Tomography) of the Sinuses? Computed tomography, ... the body being studied. top of page How is the procedure performed? The technologist begins by positioning ...

  16. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... the Sinuses? What is CT (Computed Tomography) of the Sinuses? Computed tomography, more commonly known as a ... of page What are some common uses of the procedure? CT of the sinuses is primarily used ...

  17. Fabrication of Blended Polycaprolactone/Poly (Lactic-Co-Glycolic Acid)/β-Tricalcium Phosph