Design and characterization of a small muon tomography system

Science.gov (United States)

Jo, Woo Jin; An, Su Jung; Kim, Hyun-Il; Lee, Chae Young; Chung, Heejun; Chung, Yong Hyun

2015-02-01

Muon tomography is a useful method for monitoring special nuclear materials (SNMs) because it can provide effective information on the presence of high-Z materials, has a high enough energy to deeply penetrate large amounts of shielding, and does not lead to any health risks and danger above background. We developed a 2-D muon detector and designed a muon tomography system employing four detector modules. Two top and two bottom detectors are, respectively, employed to record the incident and the scattered muon trajectories. The detector module for the muon tomography system consists of a plastic scintillator, wavelength-shifting (WLS) fiber arrays placed orthogonally on the top and the bottom of the scintillator, and a position-sensitive photomultiplier (PSPMT). The WLS fiber arrays absorb light photons emitted by the plastic scintillator and re-emit green lights guided to the PSPMT. The light distribution among the WLS fiber arrays determines the position of the muon interaction; consequently, 3-D tomographic images can be obtained by extracting the crossing points of the individual muon trajectories by using a point-of-closest-approach algorithm. The goal of this study is to optimize the design parameters of a muon tomography system by using the Geant4 code and to experimentally evaluate the performance of the prototype detector. Images obtained by the prototype detector with a 420-nm laser light source showed good agreement with the simulation results. This indicates that the proposed detector is feasible for use in a muon tomography system and can be used to verify the Z-discrimination capability of the muon tomography system.

Transmission computed tomography data acquisition with a SPECT system

International Nuclear Information System (INIS)

Greer, K.L.; Harris, C.C.; Jaszczak, R.J.; Coleman, R.E.; Hedlund, L.W.; Floyd, C.E.; Manglos, S.H.

1987-01-01

Phantom and animal transmission computed tomography (TCT) scans were performed with a camera-based single photon emission computed tomography (SPECT) system to determine system linearity as a function of object density, which is important in the accurate determination of attenuation coefficients for SPECT attenuation compensation. Results from phantoms showed promise in providing a linear relationship in measuring density while maintaining good image resolution. Animal images were essentially free of artifacts. Transmission computed tomography scans derived from a SPECT system appear to have the potential to provide data suitable for incorporation in an attenuation compensation algorithm at relatively low (calculated) radiation doses to the subjects

Neutron and X-ray Tomography (NeXT) system for simultaneous, dual modality tomography

Science.gov (United States)

LaManna, J. M.; Hussey, D. S.; Baltic, E.; Jacobson, D. L.

2017-11-01

Dual mode tomography using neutrons and X-rays offers the potential of improved estimation of the composition of a sample from the complementary interaction of the two probes with the sample. We have developed a simultaneous neutron and 90 keV X-ray tomography system that is well suited to the study of porous media systems such as fuel cells, concrete, unconventional reservoir geologies, limestones, and other geological media. We present the characteristic performance of both the neutron and X-ray modalities. We illustrate the use of the simultaneous acquisition through improved phase identification in a concrete core.

First image from a combined positron emission tomography and field-cycled MRI system.

Science.gov (United States)

Bindseil, Geron A; Gilbert, Kyle M; Scholl, Timothy J; Handler, William B; Chronik, Blaine A

2011-07-01

Combining positron emission tomography and MRI modalities typically requires using either conventional MRI with a MR-compatible positron emission tomography system or a modified MR system with conventional positron emission tomography. A feature of field-cycled MRI is that all magnetic fields can be turned off rapidly, enabling the use of conventional positron emission tomography detectors based on photomultiplier tubes. In this demonstration, two photomultiplier tube-based positron emission tomography detectors were integrated with a field-cycled MRI system (0.3 T/4 MHz) by placing them into a 9-cm axial gap. A positron emission tomography-MRI phantom consisting of a triangular arrangement of positron-emitting point sources embedded in an onion was imaged in a repeating interleaved sequence of ∼1 sec MRI then 1 sec positron emission tomography. The first multimodality images from the combined positron emission tomography and field-cycled MRI system show no additional artifacts due to interaction between the systems and demonstrate the potential of this approach to combining positron emission tomography and MRI. Copyright © 2010 Wiley-Liss, Inc.

Development of Hardware Dual Modality Tomography System

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R. M. Zain

2009-06-01

Full Text Available The paper describes the hardware development and performance of the Dual Modality Tomography (DMT system. DMT consists of optical and capacitance sensors. The optical sensors consist of 16 LEDs and 16 photodiodes. The Electrical Capacitance Tomography (ECT electrode design use eight electrode plates as the detecting sensor. The digital timing and the control unit have been developing in order to control the light projection of optical emitters, switching the capacitance electrodes and to synchronize the operation of data acquisition. As a result, the developed system is able to provide a maximum 529 set data per second received from the signal conditioning circuit to the computer.

Tomography patterns of lung disease in systemic sclerosis

Energy Technology Data Exchange (ETDEWEB)

Bastos, Andrea de Lima; Correa, Ricardo de Amorim; Ferreira, Gilda Aparecida, E-mail: andrealb@ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Faculdade de Medicina

2016-09-15

Currently, lung impairment is the leading factor responsible for the morbidity and mortality associated with systemic sclerosis. Therefore, the recognition of the various tomography patterns becomes decisive in the clinical management of these patients. In high-resolution computed tomography studies, the most common pattern is that of nonspecific interstitial pneumonia. However, there are other forms of lung involvement that must also be recognized. The aim of this study was to review the literature on the main changes resulting from pulmonary involvement in systemic sclerosis and the corresponding radiological findings, considering the current classification of interstitial diseases. We searched the Medline (PubMed), Lilacs, and SciELO databases in order to select articles related to pulmonary changes in systemic sclerosis and published in English between 2000 and 2015. The pulmonary changes seen on computed tomography in systemic sclerosis are varied and are divided into three main categories: interstitial, alveolar, and vascular. Interstitial changes constitute the most common type of pulmonary involvement in systemic sclerosis. However, alveolar and vascular manifestations must also be recognized and considered in the presence of atypical clinical presentations and inadequate treatment responses. (author)

Tomography patterns of lung disease in systemic sclerosis

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Andréa de Lima Bastos

Full Text Available Abstract Currently, lung impairment is the leading factor responsible for the morbidity and mortality associated with systemic sclerosis. Therefore, the recognition of the various tomography patterns becomes decisive in the clinical management of these patients. In high-resolution computed tomography studies, the most common pattern is that of nonspecific interstitial pneumonia. However, there are other forms of lung involvement that must also be recognized. The aim of this study was to review the literature on the main changes resulting from pulmonary involvement in systemic sclerosis and the corresponding radiological findings, considering the current classification of interstitial diseases. We searched the Medline (PubMed, Lilacs, and SciELO databases in order to select articles related to pulmonary changes in systemic sclerosis and published in English between 2000 and 2015. The pulmonary changes seen on computed tomography in systemic sclerosis are varied and are divided into three main categories: interstitial, alveolar, and vascular. Interstitial changes constitute the most common type of pulmonary involvement in systemic sclerosis. However, alveolar and vascular manifestations must also be recognized and considered in the presence of atypical clinical presentations and inadequate treatment responses.

Tomography patterns of lung disease in systemic sclerosis

International Nuclear Information System (INIS)

Bastos, Andrea de Lima; Correa, Ricardo de Amorim; Ferreira, Gilda Aparecida

2016-01-01

Currently, lung impairment is the leading factor responsible for the morbidity and mortality associated with systemic sclerosis. Therefore, the recognition of the various tomography patterns becomes decisive in the clinical management of these patients. In high-resolution computed tomography studies, the most common pattern is that of nonspecific interstitial pneumonia. However, there are other forms of lung involvement that must also be recognized. The aim of this study was to review the literature on the main changes resulting from pulmonary involvement in systemic sclerosis and the corresponding radiological findings, considering the current classification of interstitial diseases. We searched the Medline (PubMed), Lilacs, and SciELO databases in order to select articles related to pulmonary changes in systemic sclerosis and published in English between 2000 and 2015. The pulmonary changes seen on computed tomography in systemic sclerosis are varied and are divided into three main categories: interstitial, alveolar, and vascular. Interstitial changes constitute the most common type of pulmonary involvement in systemic sclerosis. However, alveolar and vascular manifestations must also be recognized and considered in the presence of atypical clinical presentations and inadequate treatment responses. (author)

Integrated electromagnetic (EM) and Electrical Resistivity Tomography (ERT) geophysical studies of environmental impact of Awotan dumpsite in Ibadan, southwestern Nigeria

Science.gov (United States)

Osinowo, Olawale Olakunle; Falufosi, Michael Oluseyi; Omiyale, Eniola Oluwatosin

2018-04-01

This study attempts to establish the level of contamination caused by the decomposition of wastes by defining the lateral distribution and the vertical limit of leachate induced zone of anomalous conductivity distribution within the subsurface through the analyses of Electromagnetic (EM) and Electrical Resistivity Tomography (ERT) data, generated from the integrated geophysical survey over Awotan landfill dumpsite, in Ibadan, southwest Nigeria. Nine (9) EM and ERT profiles each were established within and around the Awotan landfill site. EM data were acquire at 5 m station interval using 10 m, 20 m and 40 m inter-coil spacings, while ERT stations were occupied at 2 m electrode spacing using dipole-dipole electrode configuration. The near perfect agreement between the two sets of data generated from the EM and ERT surveys over the Awotan landfill site as well as the subsurface imaging ability of these geophysical methods to delineate the region of elevated contamination presented in the form of anomalously high apparent ground conductivity and low subsurface resistivity distribution, suggest the importance of integrating electromagnetic and electrical resistivity investigation techniques for environmental studies and more importantly for selecting appropriate landfill dump site location such with ability to retain the generated contaminants and thus prevent environmental pollution.

Dual-Modality Imaging of the Human Finger Joint Systems by Using Combined Multispectral Photoacoustic Computed Tomography and Ultrasound Computed Tomography

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Yubin Liu

2016-01-01

Full Text Available We developed a homemade dual-modality imaging system that combines multispectral photoacoustic computed tomography and ultrasound computed tomography for reconstructing the structural and functional information of human finger joint systems. The fused multispectral photoacoustic-ultrasound computed tomography (MPAUCT system was examined by the phantom and in vivo experimental tests. The imaging results indicate that the hard tissues such as the bones and the soft tissues including the blood vessels, the tendon, the skins, and the subcutaneous tissues in the finger joints systems can be effectively recovered by using our multimodality MPAUCT system. The developed MPAUCT system is able to provide us with more comprehensive information of the human finger joints, which shows its potential for characterization and diagnosis of bone or joint diseases.

The State of Emergency Medical Services (EMS) Systems in Africa.

Science.gov (United States)

Mould-Millman, Nee-Kofi; Dixon, Julia M; Sefa, Nana; Yancey, Arthur; Hollong, Bonaventure G; Hagahmed, Mohamed; Ginde, Adit A; Wallis, Lee A

2017-06-01

Introduction Little is known about the existence, distribution, and characteristics of Emergency Medical Services (EMS) systems in Africa, or the corresponding epidemiology of prehospital illness and injury. A survey was conducted between 2013 and 2014 by distributing a detailed EMS system questionnaire to experts in paper and electronic versions. The questionnaire ascertained EMS systems' jurisdiction, operations, finance, clinical care, resources, and regulatory environment. The discovery of respondents with requisite expertise occurred in multiple phases, including snowball sampling, a review of published scientific literature, and a rigorous search of the Internet. The survey response rate was 46%, and data represented 49 of 54 (91%) African countries. Twenty-five EMS systems were identified and distributed among 16 countries (30% of African countries). There was no evidence of EMS systems in 33 (61%) countries. A total of 98,574,731 (8.7%) of the African population were serviced by at least one EMS system in 2012. The leading causes of EMS transport were (in order of decreasing frequency): injury, obstetric, respiratory, cardiovascular, and gastrointestinal complaints. Nineteen percent of African countries had government-financed EMS systems and 26% had a toll-free public access telephone number. Basic emergency medical technicians (EMTs) and Basic Life Support (BLS)-equipped ambulances were the most common cadre of provider and ambulance level, respectively (84% each). Emergency Medical Services systems exist in one-third of African countries. Injury and obstetric complaints are the leading African prehospital conditions. Only a minority (<9.0%) of Africans have coverage by an EMS system. Most systems were predominantly BLS, government operated, and fee-for-service. Mould-Millman NK , Dixon JM , Sefa N , Yancey A , Hollong BG , Hagahmed M , Ginde AA , Wallis LA . The state of Emergency Medical Services (EMS) systems in Africa. Prehosp Disaster Med. 2017;32(3):273-283.

Weighted expectation maximization reconstruction algorithms with application to gated megavoltage tomography

International Nuclear Information System (INIS)

Zhang Jin; Shi Daxin; Anastasio, Mark A; Sillanpaa, Jussi; Chang Jenghwa

2005-01-01

We propose and investigate weighted expectation maximization (EM) algorithms for image reconstruction in x-ray tomography. The development of the algorithms is motivated by the respiratory-gated megavoltage tomography problem, in which the acquired asymmetric cone-beam projections are limited in number and unevenly sampled over view angle. In these cases, images reconstructed by use of the conventional EM algorithm can contain ring- and streak-like artefacts that are attributable to a combination of data inconsistencies and truncation of the projection data. By use of computer-simulated and clinical gated fan-beam megavoltage projection data, we demonstrate that the proposed weighted EM algorithms effectively mitigate such image artefacts. (note)

Computed tomography of the central nervous system in small animals

International Nuclear Information System (INIS)

Tipold, A.; Tipold, E.

1991-01-01

With computed tomography in 44 small animals some well defined anatomical structures and pathological processes of the central nervous system are described. Computed tomography is not only necessary for the diagnosis of tumors; malformations, inflammatory, degenerative and vascular diseases and traumas are also visible

Hardware Developments of an Ultrasonic Tomography Measurement System

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Hudabiyah ARSHAD AMARI

2010-01-01

Full Text Available This research provides new technique in ultrasonic tomography by using ultrasonic transceivers instead of using separate transmitter-receiver pair. The numbers of sensors or transducers used to acquire data plays an important role to generate high resolution tomography images. The configuration of these sensors is a crucial factor in the efficiency of data acquisition. Instead of using common separated transmitter – receiver, an alternative approach has been taken to use dual functionality ultrasonic transceiver. A prototype design of sensor’s jig that will hold 16 transceivers of 14.1mm has been design. Transmission-mode approach with fan beam technique has been used for sensing the flow of gas, liquid and solid. This paper also explains the circuitry designs for the Ultrasonic Tomography System.

A PC-based discrete tomography imaging software system for assaying radioactive waste containers

International Nuclear Information System (INIS)

Palacios, J.C.; Longoria, L.C.; Santos, J.; Perry, R.T.

2003-01-01

A PC-based discrete tomography imaging software system for assaying radioactive waste containers for use in facilities in Mexico has been developed. The software system consists of three modules: (i) for reconstruction transmission tomography, (ii) for reconstruction emission tomography, and (iii) for simulation tomography. The Simulation Module is an interactive computer program that is used to create simulated databases for input to the Reconstruction Modules. These databases may be used in the absence of physical measurements to insure that the tomographic theoretical models are valid and that the coding accurately describes these models. Simulation may also be used to determine the detection limits of the reconstruction methodology. A description of the system, the theory, and a demonstration of the systems capabilities is provided in the paper. The hardware for this system is currently under development

Application of the EM algorithm to radiographic images.

Science.gov (United States)

Brailean, J C; Little, D; Giger, M L; Chen, C T; Sullivan, B J

1992-01-01

The expectation maximization (EM) algorithm has received considerable attention in the area of positron emitted tomography (PET) as a restoration and reconstruction technique. In this paper, the restoration capabilities of the EM algorithm when applied to radiographic images is investigated. This application does not involve reconstruction. The performance of the EM algorithm is quantitatively evaluated using a "perceived" signal-to-noise ratio (SNR) as the image quality metric. This perceived SNR is based on statistical decision theory and includes both the observer's visual response function and a noise component internal to the eye-brain system. For a variety of processing parameters, the relative SNR (ratio of the processed SNR to the original SNR) is calculated and used as a metric to compare quantitatively the effects of the EM algorithm with two other image enhancement techniques: global contrast enhancement (windowing) and unsharp mask filtering. The results suggest that the EM algorithm's performance is superior when compared to unsharp mask filtering and global contrast enhancement for radiographic images which contain objects smaller than 4 mm.

Development of the EM tomography system. Part 2. Sensitivity studies of anomalous body by model studies; EM tomography system no kaihatsu. 2. Model kaiseki ni yoru ijotai no kando chosa kekka

Energy Technology Data Exchange (ETDEWEB)

Kumekawa, Y; Miura, Y; Takasugi, S [GERD Geothermal Energy Research and Development Co. Ltd., Tokyo (Japan); Arai, E [Metal Mining Agency of Japan, Tokyo (Japan)

1997-05-27

A model analysis was used to investigate sensitivity of a two-dimensional structure on a resistivity anomalous body by using an electromagnetic tomography system. The resistivity model handled a three-dimensional structure. The model was prepared as a pseudo two-dimensional model in which a low resistivity anomalous body with 1 ohm-m was incorporated that has a basic length of 1000 m in the Y-direction in a homogenous medium having 100 ohm-m. As a result of the analysis, the following matters were elucidated: if a low resistivity anomalous body is present in a shallow subsurface, its impact starts appearing from lower frequencies than when the anomalous body exists only at a greater depth; if a high resistivity anomalous body exists, the detection sensitivity is lower than for the low resistivity anomalous body, but the analysis would be possible by using the phase because the phase has made a greater change; the source TxZ shows a change from lower frequencies than for the source TxX, and the amount of change is greater, hence the detection sensitivity on an anomalous body may be said higher with the source TxZ; however, for the anomalous body in shallow subsurface, the source TxX is more effective since it is not subjected to a too great impact at a greater depth. 5 refs., 7 figs.

A European Land Mobile Satellite System via EMS

Science.gov (United States)

Ananasso, Fulvio; Mistretta, Ignazio

1991-10-01

The paper analyzes the technical and market issues that influence the strategy of implementation of a Land Mobile Satellite System via the payload EMS (European Mobile System) embarked on ITALSAT F-2. The final goal is to determine services, network architecture, and added value chain that make LMSS via EMS profitable for a typical telecommunication company.

An All-Fiber-Optic Combined System of Noncontact Photoacoustic Tomography and Optical Coherence Tomography.

Science.gov (United States)

Eom, Jonghyun; Shin, Jun Geun; Park, Soongho; Rim, Sunghwan; Lee, Byeong Ha

2016-05-20

We propose an all-fiber-based dual-modal imaging system that combines noncontact photoacoustic tomography (PAT) and optical coherence tomography (OCT). The PAT remotely measures photoacoustic (PA) signals with a 1550-nm laser on the surface of a sample by utilizing a fiber interferometer as an ultrasound detector. The fiber-based OCT, employing a swept-source laser centered at 1310 nm, shares the sample arm of the PAT system. The fiber-optic probe for the combined system was homemade with a lensed single-mode fiber (SMF) and a large-core multimode fiber (MMF). The compact and robust common probe is capable of obtaining both the PA and the OCT signals at the same position without any physical contact. Additionally, the MMF of the probe delivers the short pulses of a Nd:YAG laser to efficiently excite the PA signals. We experimentally demonstrate the feasibility of the proposed dual-modal system with a phantom made of a fishing line and a black polyethylene terephthalate fiber in a tissue mimicking solution. The all-fiber-optic system, capable of providing complementary information about absorption and scattering, has a promising potential in minimally invasive and endoscopic imaging.

An All-Fiber-Optic Combined System of Noncontact Photoacoustic Tomography and Optical Coherence Tomography

Science.gov (United States)

Eom, Jonghyun; Shin, Jun Geun; Park, Soongho; Rim, Sunghwan; Lee, Byeong Ha

2016-01-01

We propose an all-fiber-based dual-modal imaging system that combines noncontact photoacoustic tomography (PAT) and optical coherence tomography (OCT). The PAT remotely measures photoacoustic (PA) signals with a 1550-nm laser on the surface of a sample by utilizing a fiber interferometer as an ultrasound detector. The fiber-based OCT, employing a swept-source laser centered at 1310 nm, shares the sample arm of the PAT system. The fiber-optic probe for the combined system was homemade with a lensed single-mode fiber (SMF) and a large-core multimode fiber (MMF). The compact and robust common probe is capable of obtaining both the PA and the OCT signals at the same position without any physical contact. Additionally, the MMF of the probe delivers the short pulses of a Nd:YAG laser to efficiently excite the PA signals. We experimentally demonstrate the feasibility of the proposed dual-modal system with a phantom made of a fishing line and a black polyethylene terephthalate fiber in a tissue mimicking solution. The all-fiber-optic system, capable of providing complementary information about absorption and scattering, has a promising potential in minimally invasive and endoscopic imaging. PMID:27213392

An All-Fiber-Optic Combined System of Noncontact Photoacoustic Tomography and Optical Coherence Tomography

Directory of Open Access Journals (Sweden)

Jonghyun Eom

2016-05-01

Full Text Available We propose an all-fiber-based dual-modal imaging system that combines noncontact photoacoustic tomography (PAT and optical coherence tomography (OCT. The PAT remotely measures photoacoustic (PA signals with a 1550-nm laser on the surface of a sample by utilizing a fiber interferometer as an ultrasound detector. The fiber-based OCT, employing a swept-source laser centered at 1310 nm, shares the sample arm of the PAT system. The fiber-optic probe for the combined system was homemade with a lensed single-mode fiber (SMF and a large-core multimode fiber (MMF. The compact and robust common probe is capable of obtaining both the PA and the OCT signals at the same position without any physical contact. Additionally, the MMF of the probe delivers the short pulses of a Nd:YAG laser to efficiently excite the PA signals. We experimentally demonstrate the feasibility of the proposed dual-modal system with a phantom made of a fishing line and a black polyethylene terephthalate fiber in a tissue mimicking solution. The all-fiber-optic system, capable of providing complementary information about absorption and scattering, has a promising potential in minimally invasive and endoscopic imaging.

Dynamics of quantum tomography in an open system

Science.gov (United States)

Uchiyama, Chikako

2015-06-01

In this study, we provide a way to describe the dynamics of quantum tomography in an open system with a generalized master equation, considering a case where the relevant system under tomographic measurement is influenced by the environment. We apply this to spin tomography because such situations typically occur in μSR (muon spin rotation/relaxation/resonance) experiments where microscopic features of the material are investigated by injecting muons as probes. As a typical example to describe the interaction between muons and a sample material, we use a spin-boson model where the relevant spin interacts with a bosonic environment. We describe the dynamics of a spin tomogram using a time-convolutionless type of generalized master equation that enables us to describe short time scales and/or low-temperature regions. Through numerical evaluation for the case of Ohmic spectral density with an exponential cutoff, a clear interdependency is found between the time evolution of elements of the density operator and a spin tomogram. The formulation in this paper may provide important fundamental information for the analysis of results from, for example, μSR experiments on short time scales and/or in low-temperature regions using spin tomography.

A novel storage system for cryoEM samples.

Science.gov (United States)

Scapin, Giovanna; Prosise, Winifred W; Wismer, Michael K; Strickland, Corey

2017-07-01

We present here a new CryoEM grid boxes storage system designed to simplify sample labeling, tracking and retrieval. The system is based on the crystal pucks widely used by the X-ray crystallographic community for storage and shipping of crystals. This system is suitable for any cryoEM laboratory, but especially for large facilities that will need accurate tracking of large numbers of samples coming from different sources. Copyright © 2017. Published by Elsevier Inc.

Simulation of a small muon tomography station system based on RPCs

Science.gov (United States)

Chen, S.; Li, Q.; Ma, J.; Kong, H.; Ye, Y.; Gao, J.; Jiang, Y.

2014-10-01

In this work, Monte Carlo simulations were used to study the performance of a small muon Tomography Station based on four glass resistive plate chambers(RPCs) with a spatial resolution of approximately 1.0mm (FWHM). We developed a simulation code to generate cosmic ray muons with the appropriate distribution of energies and angles. PoCA and EM algorithm were used to rebuild the objects for comparison. We compared Z discrimination time with and without muon momentum measurement. The relation between Z discrimination time and spatial resolution was also studied. Simulation results suggest that mean scattering angle is a better Z indicator and upgrading to larger RPCs will improve reconstruction image quality.

Esclerose sistêmica progressiva: aspectos na tomografia computadorizada de alta resolução Progressive systemic sclerosis: high-resolution computed tomography findings

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Emerson L. Gasparetto

2005-09-01

Full Text Available OBJETIVO: Descrever os achados de tomografia computadorizada de alta resolução de pacientes com esclerose sistêmica pulmonar, independentemente dos sintomas respiratórios. MATERIAIS E MÉTODOS: Foram revisados 73 exames de tomografia computadorizada de alta resolução de 44 pacientes com diagnóstico de esclerodermia estabelecido através de critérios clínicos e laboratoriais. Os exames foram revisados por dois radiologistas, que estabeleceram os achados por consenso. RESULTADOS: Em 91,8% (n = 67 dos exames observaram-se alterações. Os principais achados foram lesões de padrão reticular (90,4%, opacidades em vidro-fosco (63%, bronquiectasias e bronquiolectasias de tração (56,2%, dilatação esofagiana (46,6%, faveolamento (28,8% e sinais de hipertensão pulmonar (15,6%. Na maioria dos casos as lesões eram bilaterais (89% e simétricas (58,5%. Quanto à localização, houve predomínio de lesões basais (91,2% e periféricas (92,2%. CONCLUSÃO: A esclerose sistêmica progressiva acarreta fibrose pulmonar na maioria dos pacientes, caracterizada principalmente por lesão reticular basal e periférica.OBJECTIVE: To describe the high-resolution computed tomography findings in the lung of patients with systemic sclerosis, independently of the respiratory symptoms. MATERIALS AND METHODS: Seventy-three high-resolution computed tomography scans of 44 patients with clinical diagnosis of systemic sclerosis were reviewed and defined by the consensus of two radiologists. RESULTS: Abnormalities were seen in 91.8% (n = 67 of the scans. The most frequent findings were reticular pattern (90.4%, ground-glass opacities (63%, traction bronchiectasis and bronchiolectasis (56.2%, esophageal dilatation (46.6%, honeycombing pattern (28.8% and signs of pulmonary hypertension (15.6%. In most cases the lesions were bilateral (89% and symmetrical (58.5%. The lesions were predominantly located in the basal (91.2% and peripheral (92.2% regions. CONCLUSION: In

Frequency of suspected cases of neurocysticercosis detected by computed skull tomography in Santa Maria, RS, Brazil Freqüência de casos suspeitos de neurocisticercose em tomografias computadorizadas de crânio em Santa Maria, RS, Brasil

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José Edson Paz da SILVA

2000-02-01

Full Text Available Due to the lack of studies about neurocysticercosis in the South of Brazil, an investigation was conducted to determine the percentage of suspected cases of neurocysticercosis in computed tomography diagnoses in Santa Maria, RS, from January 1997 to December 1998. Of 6300 computed tomographies (CT of the skull performed at the private Hospital de Caridade Astrogildo de Azevedo, 80, i.e., 1.27% were suspected of neurocysticercosis. Fifty were women (62.5% and 30 were men (37.5%. The most frequent radiological manifestation indicating neurocysticercosis was the presence of calcifications (isolated or associated, with a 95% rate (76 cases, while the presence of hypodense lesions reached a 5% rate (4 cases. After routine analysis, each CT was evaluated again and the suspected cases were confirmed. The percentage of suspected cases of neurocysticercosis detected by CT in the present study carried out in Santa Maria was considered low (1.27%. This can be explained by the fact that tomography is not accessible to the economically underprivileged population of Santa Maria. We hope that the present study can alert the population and the professionals to the fact that neurocysticercosis is a more frequent disease than indicated by the few diagnoses made.Com o objetivo de iniciar um estudo sobre a neurocisticercose no Sul do Brasil, foi verificada a porcentagem de casos suspeitos de neurocisticercose em tomografia computadorizada de crânio (TCC em Santa Maria, entre janeiro de 1997 e dezembro de 1998. Os resultados mostraram que entre 6300 TCC realizadas no Hospital de Caridade Astrogildo de Azevedo, 80, isto é, 1,27% eram suspeitas de neurocisticercose. Constatamos que 50 eram mulheres (62,5% e 30 homens (37,5%. A manifestação radiológica mais freqüente para indicar neurocisticercose foi a calcificação (isolada ou associada com 95% (76 casos, enquanto a presença de lesões hipodensas foi de 5% (4 casos. Após a análise de rotina cada TCC foi

Imaging of the dopaminergic neurotransmission system using single-photon emission tomography and positron emission tomography in patients with parkinsonism

International Nuclear Information System (INIS)

Booij, J.; Tissingh, G.; Winogrodzka, A.; Royen, E.A. van

1999-01-01

Parkinsonism is a feature of a number of neurodegenerative diseases, including Parkinson's disease, multiple system atrophy and progressive supranuclear palsy. The results of post-mortem studies point to dysfunction of the dopaminergic neurotransmitter system in patients with parkinsonism. Nowadays, by using single-photon emission tomography (SPET) and positron emission tomography (PET) it is possible to visualise both the nigrostriatal dopaminergic neurons and the striatal dopamine D 2 receptors in vivo. Consequently, SPET and PET imaging of elements of the dopaminergic system can play an important role in the diagnosis of several parkinsonian syndromes. This review concentrates on findings of SPET and PET studies of the dopaminergic neurotransmitter system in various parkinsonian syndromes. (orig.)

Development of the electromagnetic tomography system. Sensitivity study of anomalous body by model studies; EM tomography system no kaihatsu. Model kaiseki ni yoru ijotai no kando chosa kekka

Energy Technology Data Exchange (ETDEWEB)

Kumekawa, Y; Miura, Y; Takasugi, S [Geothermal Energy Research and Development Co. Ltd., Tokyo (Japan); Arai, E [Metal Mining Agency of Japan, Tokyo (Japan)

1996-05-01

An examination was made by a model analysis on sensitivity and the like against a resistive anomalous body, in connection with an electromagnetic tomography system with surface earthquake sources and underground receiver arrangements. A resistivity model was of a three-dimensional structure, and built with a 5 ohm{center_dot}m low resistivity anomalous body assembled in a 100 ohm{center_dot}m homogeneous medium. As a result of the examination, it was shown that the size limitation of an analyzable anomalous body was 50{times}50{times}20m at a frequency of 8 to 10kHz and that a system with high precision in a high frequency range was necessary. The examination of effects under a shallow anomalous body revealed, for example, that the fluctuation of a low frequency response was large compared with a deep anomalous body and that, where a second anomalous body existed under it, the effect also appeared with a surface earthquake source positioned in the opposite side from the anomalous body. The examination of effects under the three dimensional structure revealed, for example, that a remarkable change appeared in the data with the change in the inclined angle of the transmission line against the strike of the anomalous body. 4 refs., 7 figs.

Digital optical tomography system for dynamic breast imaging

Science.gov (United States)

Flexman, Molly L.; Khalil, Michael A.; Al Abdi, Rabah; Kim, Hyun K.; Fong, Christopher J.; Desperito, Elise; Hershman, Dawn L.; Barbour, Randall L.; Hielscher, Andreas H.

2011-07-01

Diffuse optical tomography has shown promising results as a tool for breast cancer screening and monitoring response to chemotherapy. Dynamic imaging of the transient response of the breast to an external stimulus, such as pressure or a respiratory maneuver, can provide additional information that can be used to detect tumors. We present a new digital continuous-wave optical tomography system designed to simultaneously image both breasts at fast frame rates and with a large number of sources and detectors. The system uses a master-slave digital signal processor-based detection architecture to achieve a dynamic range of 160 dB and a frame rate of 1.7 Hz with 32 sources, 64 detectors, and 4 wavelengths per breast. Included is a preliminary study of one healthy patient and two breast cancer patients showing the ability to identify an invasive carcinoma based on the hemodynamic response to a breath hold.

High speed laser tomography system

Science.gov (United States)

Samsonov, D.; Elsaesser, A.; Edwards, A.; Thomas, H. M.; Morfill, G. E.

2008-03-01

A high speed laser tomography system was developed capable of acquiring three-dimensional (3D) images of optically thin clouds of moving micron-sized particles. It operates by parallel-shifting an illuminating laser sheet with a pair of galvanometer-driven mirrors and synchronously recording two-dimensional (2D) images of thin slices of the imaged volume. The maximum scanning speed achieved was 120000slices/s, sequences of 24 volume scans (up to 256 slices each) have been obtained. The 2D slices were stacked to form 3D images of the volume, then the positions of the particles were identified and followed in the consecutive scans. The system was used to image a complex plasma with particles moving at speeds up to cm/s.

Imaging phase holdup distribution of three phase flow systems using dual source gamma ray tomography

International Nuclear Information System (INIS)

Varma, Rajneesh; Al-Dahhan, Muthanna; O'Sullivan, Joseph

2008-01-01

Full text: Multiphase reaction and process systems are used in abundance in the chemical and biochemical industry. Tomography has been successfully employed to visualize the hydrodynamics of multiphase systems. Most of the tomography methods (gamma ray, x-ray and electrical capacitance and resistance) have been successfully implemented for two phase dynamic systems. However, a significant number of chemical and biochemical systems consists of dynamic three phases. Research effort directed towards the development of tomography techniques to image such dynamic system has met with partial successes for specific systems with applicability to limited operating conditions. A dual source tomography scanner has been developed that uses the 661 keV and 1332 keV photo peaks from the 137 Cs and 60 Co for imaging three phase systems. A new approach has been developed and applied that uses the polyenergetic Alternating Minimization (A-M) algorithm, developed by O'Sullivan and Benac (2007), for imaging the holdup distribution in three phases' dynamic systems. The new approach avoids the traditional post image processing approach used to determine the holdup distribution where the attenuation images of the mixed flow obtained from gamma ray photons of two different energies are used to determine the holdup of three phases. In this approach the holdup images are directly reconstructed from the gamma ray transmission data. The dual source gamma ray tomography scanner and the algorithm were validated using a three phase phantom. Based in the validation, three phase holdup studies we carried out in slurry bubble column containing gas liquid and solid phases in a dynamic state using the dual energy gamma ray tomography. The key results of the holdup distribution studies in the slurry bubble column along with the validation of the dual source gamma ray tomography system would be presented and discussed

Complaints against an EMS system.

Science.gov (United States)

Colwell, Christopher B; Pons, Peter T; Pi, Randy

2003-11-01

Complaints against Emergency Medical Services (EMS) agencies represent a concerning and potentially time-consuming problem for all involved in the delivery of prehospital emergency medical care. The objective of this study was to identify the source of complaints against an EMS system to help focus quality and performance improvement and customer service efforts. We conducted a retrospective review of complaints filed against a busy urban EMS agency over a 6-year period. All complaints were included, totaled by season and by year, and categorized by originator and nature of the complaint. A total of 286 complaints were registered during the 6-year period, with an average of 48 per year and 9.3 per 10,000 responses. The most common originators of complaints were patients (53%) followed by medical personnel (19%) and family members or friends (12%). Rude behavior accounted for 23% of the complaints registered, followed by technical skills (20%), transport problems (18%), and loss of belongings (13%). The identification of areas of dissatisfaction will allow focused quality and performance improvement programs directed at customer service and risk management.

X-ray micro-tomography system for small-animal imaging with zoom-in imaging capability

International Nuclear Information System (INIS)

Chun, In Kon; Cho, Myung Hye; Lee, Sang Chul; Cho, Min Hyoung; Lee, Soo Yeol

2004-01-01

Since a micro-tomography system capable of μm-resolution imaging cannot be used for whole-body imaging of a small laboratory animal without sacrificing its spatial resolution, it is desirable for a micro-tomography system to have local imaging capability. In this paper, we introduce an x-ray micro-tomography system capable of high-resolution imaging of a local region inside a small animal. By combining two kinds of projection data, one from a full field-of-view (FOV) scan of the whole body and the other from a limited FOV scan of the region of interest (ROI), we have obtained zoomed-in images of the ROI without any contrast anomalies commonly appearing in conventional local tomography. For experimental verification of the zoom-in imaging capability, we have integrated a micro-tomography system using a micro-focus x-ray source, a 1248 x 1248 flat-panel x-ray detector, and a precision scan mechanism. The mismatches between the two projection data caused by misalignments of the scan mechanism have been estimated with a calibration phantom, and the mismatch effects have been compensated in the image reconstruction procedure. Zoom-in imaging results of bony tissues with a spatial resolution of 10 lp mm -1 suggest that zoom-in micro-tomography can be greatly used for high-resolution imaging of a local region in small-animal studies

Density evaluation by computerized tomography in plain soils over different manipulation systems

International Nuclear Information System (INIS)

Pedrotti, Alceu

1996-08-01

The objective of this paper is the evaluation of a plain soil density in different culture systems determined by X ray computerized tomography.It was observed a larger variation in densities in soils profiles analysed. The identification of layers is better utilising computerized tomography than others technic

Extensive tumor thrombus of hepatocellular carcinoma in the entire portal venous system detected on fluorodeoxyglucose positron emission tomography computed tomography

International Nuclear Information System (INIS)

Agrawal, Archi; Purandare, Nilendu; Shah, Sneha; Puranik, Ameya; Rangarajan, Venkatesh

2013-01-01

Detection of thrombus is usually an incidental finding on fluorodeoxyglucose positron emission tomography/computed tomography studies. Nevertheless this is an important finding in terms of disease prognostication and in planning the treatment strategy. We herein report a case of a 50-years-old male, a diagnosed case of hepatocellular carcinoma with extensive hypermetabolic thrombus involving the entire portal venous system. (author)

Tuberculose pulmonar: achados na tomografia computadorizada de alta resolução do tórax em pacientes com doença em atividade comprovada bacteriologicamente Pulmonary tuberculosis: findings on high resolution computerized tomography of active disease on patients with bacteriological confirmation

Directory of Open Access Journals (Sweden)

CRISTIANE ALÓ CAMPOS

2002-01-01

Full Text Available Objetivo: Descrever os achados em pacientes com tuberculose pulmonar em atividade na tomografia computadorizada de alta resolução e o padrão de distribuição das lesões pelo parênquima pulmonar. Casuística e método: Foram analisadas retrospectivamente as tomografias de alta resolução de 42 pacientes com diagnóstico bacteriológico de tuberculose pulmonar ou forte suspeita clínica, com posterior confirmação bacteriológica. Resultados: Os principais sinais sugestivos de atividade encontrados foram nódulos do espaço aéreo (83%, nódulos centrolobulares (74%, aspecto de árvore em brotamento (67%, cavitações (67%, espessamento das paredes brônquicas (55%, consolidações (48%, opacidade em vidro fosco (21%, e espessamento do interstício pulmonar (9%. Conclusão: A tomografia computadorizada de alta resolução do tórax pode sugerir fortemente atividade da doença, sendo particularmente útil nos pacientes com baciloscopias negativas e/ou radiografias indeterminadas, permitindo a instituição de tratamento adequado, antes mesmo do crescimento da micobactéria em meio de cultura.Background: The aim of this study was to describe the signs of active tuberculosis in patients submitted to high resolution computerized tomography and the distribution of lesions along the pulmonary parenchyma. Material and methods: The high resolution CTs performed on 42 patients with tuberculosis either bacteriologically diagnosed or clinical suspected and later confirmed by bacteriological tests were studied. Results: The signs of disease activity observed were airspace nodule (83%, centrilobular nodule (74%, tree-in-bud pattern (67%, cavitations (67%, bronchial thickening (55%, parenchymal consolidations (48%, ground glass opacity (21% and thickening of the inter and intralobular septa (9%. Conclusion: High resolution computed tomography can be strongly suggestive of disease activity, is particularly helpful in patients with negative smear and

Turbocharging Quantum Tomography

Energy Technology Data Exchange (ETDEWEB)

Blume-Kohout, Robin J. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Gamble, John King [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Nielsen, Erik [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Maunz, Peter Lukas Wilhelm [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Scholten, Travis L. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Rudinger, Kenneth Michael [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

2015-01-01

Quantum tomography is used to characterize quantum operations implemented in quantum information processing (QIP) hardware. Traditionally, state tomography has been used to characterize the quantum state prepared in an initialization procedure, while quantum process tomography is used to characterize dynamical operations on a QIP system. As such, tomography is critical to the development of QIP hardware (since it is necessary both for debugging and validating as-built devices, and its results are used to influence the next generation of devices). But tomography suffers from several critical drawbacks. In this report, we present new research that resolves several of these flaws. We describe a new form of tomography called gate set tomography (GST), which unifies state and process tomography, avoids prior methods critical reliance on precalibrated operations that are not generally available, and can achieve unprecedented accuracies. We report on theory and experimental development of adaptive tomography protocols that achieve far higher fidelity in state reconstruction than non-adaptive methods. Finally, we present a new theoretical and experimental analysis of process tomography on multispin systems, and demonstrate how to more effectively detect and characterize quantum noise using carefully tailored ensembles of input states.

Projection neuron circuits resolved using correlative array tomography

Directory of Open Access Journals (Sweden)

Daniele eOberti

2011-04-01

Full Text Available Assessment of three-dimensional morphological structure and synaptic connectivity is essential for a comprehensive understanding of neural processes controlling behavior. Different microscopy approaches have been proposed based on light microcopy (LM, electron microscopy (EM, or a combination of both. Correlative array tomography (CAT is a technique in which arrays of ultrathin serial sections are repeatedly stained with fluorescent antibodies against synaptic molecules and neurotransmitters and imaged with LM and EM (Micheva and Smith, 2007. The utility of this correlative approach is limited by the ability to preserve fluorescence and antigenicity on the one hand, and EM tissue ultrastructure on the other. We demonstrate tissue staining and fixation protocols and a workflow that yield an excellent compromise between these multimodal imaging constraints. We adapt CAT for the study of projection neurons between different vocal brain regions in the songbird. We inject fluorescent tracers of different colors into afferent and efferent areas of HVC in zebra finches. Fluorescence of some tracers is lost during tissue preparation but recovered using anti-dye antibodies. Synapses are identified in EM imagery based on their morphology and ultrastructure and classified into projection neuron type based on fluorescence signal. Our adaptation of array tomography, involving the use of fluorescent tracers and heavy-metal rich staining and embedding protocols for high membrane contrast in EM will be useful for research aimed at statistically describing connectivity between different projection neuron types and for elucidating how sensory signals are routed in the brain and transformed into a meaningful motor output.

Time-Domain Terahertz Computed Axial Tomography NDE System

Science.gov (United States)

Zimdars, David

2012-01-01

NASA has identified the need for advanced non-destructive evaluation (NDE) methods to characterize aging and durability in aircraft materials to improve the safety of the nation's airline fleet. 3D THz tomography can play a major role in detection and characterization of flaws and degradation in aircraft materials, including Kevlar-based composites and Kevlar and Zylon fabric covers for soft-shell fan containment where aging and durability issues are critical. A prototype computed tomography (CT) time-domain (TD) THz imaging system has been used to generate 3D images of several test objects including a TUFI tile (a thermal protection system tile used on the Space Shuttle and possibly the Orion or similar capsules). This TUFI tile had simulated impact damage that was located and the depth of damage determined. The CT motion control gan try was designed and constructed, and then integrated with a T-Ray 4000 control unit and motion controller to create a complete CT TD-THz imaging system prototype. A data collection software script was developed that takes multiple z-axis slices in sequence and saves the data for batch processing. The data collection software was integrated with the ability to batch process the slice data with the CT TD-THz image reconstruction software. The time required to take a single CT slice was decreased from six minutes to approximately one minute by replacing the 320 ps, 100-Hz waveform acquisition system with an 80 ps, 1,000-Hz waveform acquisition system. The TD-THZ computed tomography system was built from pre-existing commercial off-the-shelf subsystems. A CT motion control gantry was constructed from COTS components that can handle larger samples. The motion control gantry allows inspection of sample sizes of up to approximately one cubic foot (.0.03 cubic meters). The system reduced to practice a CT-TDTHz system incorporating a COTS 80- ps/l-kHz waveform scanner. The incorporation of this scanner in the system allows acquisition of 3D

Computed tomography system

International Nuclear Information System (INIS)

Lambert, T.W.; Blake, J.E.

1981-01-01

This invention relates to computed tomography and is particularly concerned with determining the CT numbers of zones of interest in an image displayed on a cathode ray tube which zones lie in the so-called level or center of the gray scale window. (author)

Tomography system for measurement of gas properties in combustion flow field

Directory of Open Access Journals (Sweden)

Junling SONG

2017-10-01

Full Text Available This paper describes a self-designed fiber-coupled tomography system and its application in combustion diagnostics. The tomographic technique, which combines tunable diode laser spectroscopy and algebraic reconstruction technique, enables the simultaneous reconstruction of temperature and gas concentration with both spatial and temporal resolutions. The system measures a maximum diameter of 35 cm in a circular area with a minimum spatial resolution of 1 mm × 1 mm and temporal response of up to 1 kHz. Simulations validate the effects of the beam arrangement and discrete grid on reconstruction accuracy, and give the optimal beam arrangements. Experiments are made to demonstrate the tomography method, and systems are constructed in laboratory and on engineering test benches.

Design of a muon tomography system with a plastic scintillator and wavelength-shifting fiber arrays

Energy Technology Data Exchange (ETDEWEB)

Jo, Woo Jin; Kim, Hyun-Il; An, Su Jung; Lee, Chae Young [Department of Radiological Science, College of Health Science, Yonsei University, Wonju 220-710 (Korea, Republic of); Baek, Cheol-Ha [Department of Radiological Science, Dongseo University, Busan 617-716 (Korea, Republic of); Chung, Yong Hyun, E-mail: ychung@yonsei.ac.kr [Department of Radiological Science, College of Health Science, Yonsei University, Wonju 220-710 (Korea, Republic of)

2013-12-21

Recently, monitoring nuclear materials to avoid nuclear terrorism has become an important area of national security. It can be difficult to detect gamma rays from nuclear material because they are easily shielded by shielding material. Muon tomography using multiple -Coulomb scattering derived from muons can be utilized to detect special nuclear materials (SNMs) such as uranium-235 and plutonium-239. We designed a muon tomography system composed of four detector modules. The incident and scattered muon tracks can be calculated by two top and two bottom detectors, respectively. 3D tomographic images are obtained by extracting the crossing points of muon tracks with a point-of-closest-approach algorithm. The purpose of this study was to optimize the muon tomography system using Monte Carlo simulation code. The effects of the geometric parameters of the muon tomography system on material Z-discrimination capability were simulated and evaluated.

Systematic calibration of an integrated x-ray and optical tomography system for preclinical radiation research

Energy Technology Data Exchange (ETDEWEB)

Yang, Yidong, E-mail: yidongyang@med.miami.edu [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21231 and Department of Radiation Oncology, University of Miami School of Medicine, Miami, Florida 33136 (United States); Wang, Ken Kang-Hsin; Wong, John W. [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21231 (United States); Eslami, Sohrab; Iordachita, Iulian I. [Laboratory for Computational Sensing and Robotics, Johns Hopkins University, Baltimore, Maryland 21218 (United States); Patterson, Michael S. [Juravinski Cancer Centre and Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario L8S4K1 (Canada)

2015-04-15

Purpose: The cone beam computed tomography (CBCT) guided small animal radiation research platform (SARRP) has been developed for focal tumor irradiation, allowing laboratory researchers to test basic biological hypotheses that can modify radiotherapy outcomes in ways that were not feasible previously. CBCT provides excellent bone to soft tissue contrast, but is incapable of differentiating tumors from surrounding soft tissue. Bioluminescence tomography (BLT), in contrast, allows direct visualization of even subpalpable tumors and quantitative evaluation of tumor response. Integration of BLT with CBCT offers complementary image information, with CBCT delineating anatomic structures and BLT differentiating luminescent tumors. This study is to develop a systematic method to calibrate an integrated CBCT and BLT imaging system which can be adopted onboard the SARRP to guide focal tumor irradiation. Methods: The integrated imaging system consists of CBCT, diffuse optical tomography (DOT), and BLT. The anatomy acquired from CBCT and optical properties acquired from DOT serve as a priori information for the subsequent BLT reconstruction. Phantoms were designed and procedures were developed to calibrate the CBCT, DOT/BLT, and the entire integrated system. Geometrical calibration was performed to calibrate the CBCT system. Flat field correction was performed to correct the nonuniform response of the optical imaging system. Absolute emittance calibration was performed to convert the camera readout to the emittance at the phantom or animal surface, which enabled the direct reconstruction of the bioluminescence source strength. Phantom and mouse imaging were performed to validate the calibration. Results: All calibration procedures were successfully performed. Both CBCT of a thin wire and a euthanized mouse revealed no spatial artifact, validating the accuracy of the CBCT calibration. The absolute emittance calibration was validated with a 650 nm laser source, resulting in a 3

Systematic calibration of an integrated x-ray and optical tomography system for preclinical radiation research

International Nuclear Information System (INIS)

Yang, Yidong; Wang, Ken Kang-Hsin; Wong, John W.; Eslami, Sohrab; Iordachita, Iulian I.; Patterson, Michael S.

2015-01-01

Purpose: The cone beam computed tomography (CBCT) guided small animal radiation research platform (SARRP) has been developed for focal tumor irradiation, allowing laboratory researchers to test basic biological hypotheses that can modify radiotherapy outcomes in ways that were not feasible previously. CBCT provides excellent bone to soft tissue contrast, but is incapable of differentiating tumors from surrounding soft tissue. Bioluminescence tomography (BLT), in contrast, allows direct visualization of even subpalpable tumors and quantitative evaluation of tumor response. Integration of BLT with CBCT offers complementary image information, with CBCT delineating anatomic structures and BLT differentiating luminescent tumors. This study is to develop a systematic method to calibrate an integrated CBCT and BLT imaging system which can be adopted onboard the SARRP to guide focal tumor irradiation. Methods: The integrated imaging system consists of CBCT, diffuse optical tomography (DOT), and BLT. The anatomy acquired from CBCT and optical properties acquired from DOT serve as a priori information for the subsequent BLT reconstruction. Phantoms were designed and procedures were developed to calibrate the CBCT, DOT/BLT, and the entire integrated system. Geometrical calibration was performed to calibrate the CBCT system. Flat field correction was performed to correct the nonuniform response of the optical imaging system. Absolute emittance calibration was performed to convert the camera readout to the emittance at the phantom or animal surface, which enabled the direct reconstruction of the bioluminescence source strength. Phantom and mouse imaging were performed to validate the calibration. Results: All calibration procedures were successfully performed. Both CBCT of a thin wire and a euthanized mouse revealed no spatial artifact, validating the accuracy of the CBCT calibration. The absolute emittance calibration was validated with a 650 nm laser source, resulting in a 3

Research on Image Reconstruction Algorithms for Tuber Electrical Resistance Tomography System

Directory of Open Access Journals (Sweden)

Jiang Zili

2016-01-01

Full Text Available The application of electrical resistance tomography (ERT technology has been expanded to the field of agriculture, and the concept of TERT (Tuber Electrical Resistance Tomography is proposed. On the basis of the research on the forward and the inverse problems of the TERT system, a hybrid algorithm based on genetic algorithm is proposed, which can be used in TERT system to monitor the growth status of the plant tubers. The image reconstruction of TERT system is different from the conventional ERT system for two phase-flow measurement. Imaging of TERT needs more precision measurement and the conventional ERT cares more about the image reconstruction speed. A variety of algorithms are analyzed and optimized for the purpose of making them suitable for TERT system. For example: linear back projection, modified Newton-Raphson and genetic algorithm. Experimental results showed that the novel hybrid algorithm is superior to other algorithm and it can effectively improve the image reconstruction quality.

Computed tomography vs. digital radiography assessment for detection of osteolysis in asymptomatic patients with uncemented cups: a proposal for a new classification system based on computer tomography.

Science.gov (United States)

Sandgren, Buster; Crafoord, Joakim; Garellick, Göran; Carlsson, Lars; Weidenhielm, Lars; Olivecrona, Henrik

2013-10-01

Digital radiographic images in the anterior-posterior and lateral view have been gold standard for evaluation of peri-acetabular osteolysis for patients with an uncemented hip replacement. We compared digital radiographic images and computer tomography in detection of peri-acetabular osteolysis and devised a classification system based on computer tomography. Digital radiographs were compared with computer tomography on 206 hips, with a mean follow up 10 years after surgery. The patients had no clinical signs of osteolysis and none were planned for revision surgery. On digital radiographs, 192 cases had no osteolysis and only 14 cases had osteolysis. When using computer tomography there were 184 cases showing small or large osteolysis and only 22 patients had no osteolysis. A classification system for peri-acetabular osteolysis is proposed based on computer tomography that is easy to use on standard follow up evaluation. Copyright © 2013 Elsevier Inc. All rights reserved.

Tomography system having an ultrahigh speed processing unit

International Nuclear Information System (INIS)

Cox, J.P. Jr.; Gerth, V.W. Jr.

1977-01-01

A transverse section tomography system has an ultrahigh-speed data processing unit for performing back projection and updating. An x-ray scanner directs x-ray beams through a planar section of a subject from a sequence of orientations and positions. The scanner includes a movably supported radiation detector for detecting the intensity of the beams of radiation after they pass through the subject

Evaluation of Antioxidant Activities of Aqueous Extracts and Fractionation of Different Parts of <em>Elsholtzia em>ciliata>

Full Text Available Our goal was to identify the bacteria inhabiting the reproductive system of the female oriental fruit fly, <em>Bactrocera dorsalisem> (Hendel, and evaluate the chemotaxis of <em>B>. <em>dorsalis> to the metabolites produced by the bacteria. Based on 16S rRNA-based polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE, 18 operational taxonomic units (OTUs were assigned to the five bacterial classes <em>Betaproteobacteria>, <em>Alphaproteobacteria>, <em>Gammaproteobacteria>, <em>Bacilli> and <em>Actinobacteria>. Nine OTUs were assigned to <em>Gammaproteobacteria>, which was the most highly represented class. <em>Enterobacteriaceae> constituted the dominant family, and within this family, three genera and five species were identified, including <em>Enterobacter sakazakiiem>, <em>Klebsiella> <em>oxytoca>, <em>Klebsiella> <em>pneumoniae,> Raoultellaem> <em>terrigena em>and <em>Enterobacter> <em>amnigenus>. In this set, the first two species were the dominant components, and the latter three species were the minor ones. Finally, we found that the metabolites produced by <em>R.> terrigenaem>, <em>K. oxytocaem> and <em>K.> pneumoniae em>were attractive to the <em>B.> dorsalisem> adults, and in field studies, <em>B.> dorsalisem> adults were most attracted to <em>K.> oxytocaem>. Collectively, our results suggest that the female reproductive system plays an important role in the transfer of enterobacteria from the gut to fruit. Our data may prompt the development of a female-targeted population control strategy for this fly.

Role of computed tomography in emergency evaluation of the nervous system

International Nuclear Information System (INIS)

Pelletier, J.; Martini, P.

1994-01-01

Computed tomography is the essential examination in patients with severe manifestations of neurological disorders. We discuss emergency situations involving the central nervous system due to vascular and infections lesions. Trauma and acute complications of brain tumours, usually seen within a neurosurgical context, are not discussed here. (authors). 11 refs., 19 figs

Navigating 3D electron microscopy maps with EM-SURFER.

Science.gov (United States)

Esquivel-Rodríguez, Juan; Xiong, Yi; Han, Xusi; Guang, Shuomeng; Christoffer, Charles; Kihara, Daisuke

2015-05-30

The Electron Microscopy DataBank (EMDB) is growing rapidly, accumulating biological structural data obtained mainly by electron microscopy and tomography, which are emerging techniques for determining large biomolecular complex and subcellular structures. Together with the Protein Data Bank (PDB), EMDB is becoming a fundamental resource of the tertiary structures of biological macromolecules. To take full advantage of this indispensable resource, the ability to search the database by structural similarity is essential. However, unlike high-resolution structures stored in PDB, methods for comparing low-resolution electron microscopy (EM) density maps in EMDB are not well established. We developed a computational method for efficiently searching low-resolution EM maps. The method uses a compact fingerprint representation of EM maps based on the 3D Zernike descriptor, which is derived from a mathematical series expansion for EM maps that are considered as 3D functions. The method is implemented in a web server named EM-SURFER, which allows users to search against the entire EMDB in real-time. EM-SURFER compares the global shapes of EM maps. Examples of search results from different types of query structures are discussed. We developed EM-SURFER, which retrieves structurally relevant matches for query EM maps from EMDB within seconds. The unique capability of EM-SURFER to detect 3D shape similarity of low-resolution EM maps should prove invaluable in structural biology.

Improving reservoir history matching of EM heated heavy oil reservoirs via cross-well seismic tomography

KAUST Repository

Katterbauer, Klemens

2014-01-01

Enhanced recovery methods have become significant in the industry\\'s drive to increase recovery rates from oil and gas reservoirs. For heavy oil reservoirs, the immobility of the oil at reservoir temperatures, caused by its high viscosity, limits the recovery rates and strains the economic viability of these fields. While thermal recovery methods, such as steam injection or THAI, have extensively been applied in the field, their success has so far been limited due to prohibitive heat losses and the difficulty in controlling the combustion process. Electromagnetic (EM) heating via high-frequency EM radiation has attracted attention due to its wide applicability in different environments, its efficiency, and the improved controllability of the heating process. While becoming a promising technology for heavy oil recovery, its effect on overall reservoir production and fluid displacements are poorly understood. Reservoir history matching has become a vital tool for the oil & gas industry to increase recovery rates. Limited research has been undertaken so far to capture the nonlinear reservoir dynamics and significantly varying flow rates for thermally heated heavy oil reservoir that may notably change production rates and render conventional history matching frameworks more challenging. We present a new history matching framework for EM heated heavy oil reservoirs incorporating cross-well seismic imaging. Interfacing an EM heating solver to a reservoir simulator via Andrade’s equation, we couple the system to an ensemble Kalman filter based history matching framework incorporating a cross-well seismic survey module. With increasing power levels and heating applied to the heavy oil reservoirs, reservoir dynamics change considerably and may lead to widely differing production forecasts and increased uncertainty. We have shown that the incorporation of seismic observations into the EnKF framework can significantly enhance reservoir simulations, decrease forecasting

Positron Emission Tomography imaging with the SmartPET system

Energy Technology Data Exchange (ETDEWEB)

Cooper, R.J. [Department of Physics, University of Liverpool, Liverpool, Merseyside L69 7ZE (United Kingdom)], E-mail: cooperrj@ornl.gov; Boston, A.J.; Boston, H.C.; Cresswell, J.R.; Grint, A.N.; Harkness, L.J.; Nolan, P.J.; Oxley, D.C.; Scraggs, D.P.; Mather, A.R. [Department of Physics, University of Liverpool, Liverpool, Merseyside L69 7ZE (United Kingdom); Lazarus, I.; Simpson, J. [STFC Daresbury Laboratory, Daresbury, Warrington, Cheshire WA4 4AD (United Kingdom)

2009-07-21

The Small Animal Reconstruction Tomograph for Positron Emission Tomography (SmartPET) project is the development of a small animal Positron Emission Tomography (PET) demonstrator based on the use of High-Purity Germanium (HPGe) detectors and state of the art digital electronics. The experimental results presented demonstrate the current performance of this unique system. By performing high precision measurements of one of the SmartPET HPGe detectors with a range of finely collimated gamma-ray beams the response of the detector as a function of gamma-ray interaction position has been quantified, facilitating the development of parametric Pulse Shape Analysis (PSA) techniques and algorithms for the correction of imperfections in detector performance. These algorithms have then been applied to data from PET imaging measurements using two such detectors in conjunction with a specially designed rotating gantry. In this paper we show how the use of parametric PSA approaches allows over 60% of coincident events to be processed and how the nature and complexity of an event has direct implications for the quality of the resulting image.

Brief introduction of nuclear power plant emergency system EmInfoSys

International Nuclear Information System (INIS)

Xiao Yuhua; Zhao Zhigang

2014-01-01

Nuclear safety is the lifeline of nuclear energy and nuclear technology, nuclear accident emergency response is the last line of nuclear security defense, and is one of the important measures to ensure the healthy development of the nuclear energy safety. The establishment of complete function, sensitive reaction and efficient emergency management system for operation of nuclear and radiation accidents is an important task of nuclear security. From 2001 China Techenergy Co., Ltd. participated in the Qinshan, Tianwan, Ministry of Environmental Protection, Haiyang, Taishan, Fangchenggang, Sanmen, etc. nuclear emergency projects, and the nuclear emergency EmInfoSys (emergency management information system) platform was developed with independent intellectual property rights. A brief introduction about EmInfoSys system was performed in this paper. (authors)

Design of optoelectronic system for optical diffusion tomography

Directory of Open Access Journals (Sweden)

Erakhtin Igor

2017-01-01

Full Text Available This article explores issues connected with the circuit design of a device for optical diffusion tomography, which we are currently designing. We plan to use the device in experimental studies for the development of a faster method of brain hematoma detection. We reviewed currently existing methods for emergency diagnosis of hematomas, primarily the Infrascanner model 2000, for which we identified weaknesses, and outlined suggestions for improvements. This article describes the method of scanning tissues based on a triangulated arrangement of sources and receivers of optical radiation, and it discusses the optoelectronic system that implements that principle.

IgG4-associated multifocal systemic fibrosis detected by cancer screening with 18F-FDG positron emission tomography/computed tomography

International Nuclear Information System (INIS)

Soga, Shigeyoshi; Kita, Tamotsu; Hiratsuka, Miyuki; Sakaguchi, Chiharu; Shinmoto, Hiroshi; Kosuda, Shigeru; Sakata, Ikuko; Miura, Soichiro

2010-01-01

Serial fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography ( 18 F-FDG PET/CT) studies were performed with an interval of one year in a 62-year-old man with IgG4-associated multifocal systemic fibrosis (IMSF). He first underwent 18 F-FDG PET/CT cancer screening, which revealed multiple 18 F-FDG-avid uptakes in the pancreas, prostate, and lymph nodes in the upper mediastinum, pulmonary hila, porta hepatis, and the left iliac and inguinal regions. He was not symptomatic at this initial examination. The follow-up 18 F-FDG PET/CT study showed disappearance of 18 F-FDG-avid uptake foci in the pancreas despite no treatment having been administered, but demonstrated new lesions in the abdominal para-aortic region and more intense FDG uptake in the porta hepatis lesion. Serial 18 F-FDG PET/CT studies might be useful in monitoring patients with IMSF, as well as evaluating the state of systemic involvement. Findings of 18 F-FDG PET/CT may provide information useful for determining the optimal initiation of IMSF treatment. (author)

An introduction to emission computed tomography

International Nuclear Information System (INIS)

Williams, E.D.

1985-01-01

This report includes salient features of the theory and an examination of practical considerations for someone who is using or introducing tomography, selecting equipment for it or wishing to develop a clinical application. Emphasis is on gamma camera tomography. The subject is dealt with under the following headings: emission computed and gamma camera tomography and the relationship to other medical imaging techniques, the tomographic reconstruction technique theory, rotating gamma camera tomography, attenuation correction and quantitative reconstruction, other single photon tomographic techniques, positron tomography, image display, clinical application of single photon and positron tomography, and commercial systems for SPECT. Substantial bibliography. (U.K.)

monitoring la Soufrière de Guadeloupe phreatic system with muon tomography

Science.gov (United States)

Jourde, Kevin; Gibert, Dominique; Marteau, Jacques; de Bremond d'Ars, Jean; Ianigro, Jean-Christophe; Gardien, Serge; Girerd, Claude

2015-04-01

Muon tomography is a novel geophysics imaging technique that measures the flux of cosmic muons crossing geological bodies. Its attenuation is directly related to their thickness and density. On la Soufrière de Guadeloupe volcano, we could extract tiny particle flux fluctuations from the tomography signal of long-term acquisitions (a few months). We prove that atmospheric fluctuations or solar activity, which are the usual candidates for cosmic particles time modulations, cannot explain these changes leaving the volcanic dome phreatic system as the only explanation. Moreover the temporal trends we extracted from the different observation axes of our instrument show a good spatial and temporal correlation with events occuring at the surface of the volcano.

A photoacoustic tomography system for imaging of biological tissues

International Nuclear Information System (INIS)

Su Yixiong; Zhang Fan; Xu Kexin; Yao Jianquan; Wang, Ruikang K

2005-01-01

Non-invasive laser-induced photoacoustic tomography (PAT) is a promising imaging modality in the biomedical optical imaging field. This technology, based on the intrinsic optical properties of tissue and ultrasonic detection, overcomes the resolution disadvantage of pure-optical imaging caused by strong light scattering and the contrast and speckle disadvantages of pure ultrasonic imaging. Here, we report a PAT experimental system constructed in our laboratory. In our system, a Q-switched Nd : YAG pulse laser operated at 532 nm with a 8 ns pulse width is used to generate a photoacoustic signal. By using this system, the two-dimensional distribution of optical absorption in the tissue-mimicking phantom is reconstructed and has an excellent agreement with the original ones. The spatial resolution of the imaging system approaches 100 μm through about 4 cm of highly scattering medium

A plastic scintillator-based muon tomography system with an integrated muon spectrometer

International Nuclear Information System (INIS)

Anghel, V.; Armitage, J.; Baig, F.; Boniface, K.; Boudjemline, K.; Bueno, J.; Charles, E.; Drouin, P-L.; Erlandson, A.; Gallant, G.; Gazit, R.; Godin, D.; Golovko, V.V.; Howard, C.; Hydomako, R.

2015-01-01

A muon scattering tomography system which uses extruded plastic scintillator bars for muon tracking and a dedicated muon spectrometer that measures scattering through steel slabs has been constructed and successfully tested. The atmospheric muon detection efficiency is measured to be 97% per plane on average and the average intrinsic hit resolution is 2.5 mm. In addition to creating a variety of three-dimensional images of objects of interest, a quantitative study has been carried out to investigate the impact of including muon momentum measurements when attempting to detect high-density, high-Z material. As expected, the addition of momentum information improves the performance of the system. For a fixed data-taking time of 60 s and a fixed false positive fraction, the probability to detect a target increases when momentum information is used. This is the first demonstration of the use of muon momentum information from dedicated spectrometer measurements in muon scattering tomography

A plastic scintillator-based muon tomography system with an integrated muon spectrometer

Energy Technology Data Exchange (ETDEWEB)

Anghel, V. [Canadian Nuclear Laboratories Ltd (former Atomic Energy of Canada Ltd), Chalk River Laboratories, Chalk River, Canada K0J 1P0 (Canada); Armitage, J. [Department of Physics, Room 3302 Herzberg Laboratories, Carleton University, 1125 Colonel By Drive, Ottawa, Canada K1S 5B6 (Canada); Baig, F.; Boniface, K. [Canadian Nuclear Laboratories Ltd (former Atomic Energy of Canada Ltd), Chalk River Laboratories, Chalk River, Canada K0J 1P0 (Canada); Boudjemline, K. [Department of Physics, Room 3302 Herzberg Laboratories, Carleton University, 1125 Colonel By Drive, Ottawa, Canada K1S 5B6 (Canada); Bueno, J. [Advanced Applied Physics Solutions Inc., 4004 Wesbrook Mall, Vancouver, Canada V6T 2A3 (Canada); Charles, E. [Canada Border Services Agency, 79 Bentley Avenue, Ottawa, Canada K1A 0L8 (Canada); Drouin, P-L. [Defence Research and Development Canada, 3701 Carling Avenue, Ottawa, Canada K1A 0Z4 (Canada); Erlandson, A., E-mail: Andrew.Erlandson@cnl.ca [Department of Physics, Room 3302 Herzberg Laboratories, Carleton University, 1125 Colonel By Drive, Ottawa, Canada K1S 5B6 (Canada); Canadian Nuclear Laboratories Ltd (former Atomic Energy of Canada Ltd), Chalk River Laboratories, Chalk River, Canada K0J 1P0 (Canada); Gallant, G. [Canada Border Services Agency, 79 Bentley Avenue, Ottawa, Canada K1A 0L8 (Canada); Gazit, R. [Advanced Applied Physics Solutions Inc., 4004 Wesbrook Mall, Vancouver, Canada V6T 2A3 (Canada); Godin, D.; Golovko, V.V. [Canadian Nuclear Laboratories Ltd (former Atomic Energy of Canada Ltd), Chalk River Laboratories, Chalk River, Canada K0J 1P0 (Canada); Howard, C. [Defence Research and Development Canada, 3701 Carling Avenue, Ottawa, Canada K1A 0Z4 (Canada); Hydomako, R. [Advanced Applied Physics Solutions Inc., 4004 Wesbrook Mall, Vancouver, Canada V6T 2A3 (Canada); Defence Research and Development Canada, 3701 Carling Avenue, Ottawa, Canada K1A 0Z4 (Canada); and others

2015-10-21

A muon scattering tomography system which uses extruded plastic scintillator bars for muon tracking and a dedicated muon spectrometer that measures scattering through steel slabs has been constructed and successfully tested. The atmospheric muon detection efficiency is measured to be 97% per plane on average and the average intrinsic hit resolution is 2.5 mm. In addition to creating a variety of three-dimensional images of objects of interest, a quantitative study has been carried out to investigate the impact of including muon momentum measurements when attempting to detect high-density, high-Z material. As expected, the addition of momentum information improves the performance of the system. For a fixed data-taking time of 60 s and a fixed false positive fraction, the probability to detect a target increases when momentum information is used. This is the first demonstration of the use of muon momentum information from dedicated spectrometer measurements in muon scattering tomography.

A plastic scintillator-based muon tomography system with an integrated muon spectrometer

Science.gov (United States)

Anghel, V.; Armitage, J.; Baig, F.; Boniface, K.; Boudjemline, K.; Bueno, J.; Charles, E.; Drouin, P.-L.; Erlandson, A.; Gallant, G.; Gazit, R.; Godin, D.; Golovko, V. V.; Howard, C.; Hydomako, R.; Jewett, C.; Jonkmans, G.; Liu, Z.; Robichaud, A.; Stocki, T. J.; Thompson, M.; Waller, D.

2015-10-01

A muon scattering tomography system which uses extruded plastic scintillator bars for muon tracking and a dedicated muon spectrometer that measures scattering through steel slabs has been constructed and successfully tested. The atmospheric muon detection efficiency is measured to be 97% per plane on average and the average intrinsic hit resolution is 2.5 mm. In addition to creating a variety of three-dimensional images of objects of interest, a quantitative study has been carried out to investigate the impact of including muon momentum measurements when attempting to detect high-density, high-Z material. As expected, the addition of momentum information improves the performance of the system. For a fixed data-taking time of 60 s and a fixed false positive fraction, the probability to detect a target increases when momentum information is used. This is the first demonstration of the use of muon momentum information from dedicated spectrometer measurements in muon scattering tomography.

Advances in cryo-electron tomography for biology and medicine.

Science.gov (United States)

Koning, Roman I; Koster, Abraham J; Sharp, Thomas H

2018-05-01

Cryo-electron tomography (CET) utilizes a combination of specimen cryo-fixation and multi-angle electron microscopy imaging to produce three-dimensional (3D) volume reconstructions of native-state macromolecular and subcellular biological structures with nanometer-scale resolution. In recent years, cryo-electron microscopy (cryoEM) has experienced a dramatic increase in the attainable resolution of 3D reconstructions, resulting from technical improvements of electron microscopes, improved detector sensitivity, the implementation of phase plates, automated data acquisition schemes, and improved image reconstruction software and hardware. These developments also greatly increased the usability and applicability of CET as a diagnostic and research tool, which is now enabling structural biologists to determine the structure of proteins in their native cellular environment to sub-nanometer resolution. These recent technical developments have stimulated us to update on our previous review (Koning, R.I., Koster, A.J., 2009. Cryo-electron tomography in biology and medicine. Ann Anat 191, 427-445) in which we described the fundamentals of CET. In this follow-up, we extend this basic description in order to explain the aforementioned recent advances, and describe related 3D techniques that can be applied to the anatomy of biological systems that are relevant for medicine. Copyright © 2018 Elsevier GmbH. All rights reserved.

Using x-ray computed tomography in hydrology: Systems, resolutions, and limitations

DEFF Research Database (Denmark)

Wildenschild, Dorthe; Hopmans, J.W.; Vaz, C.M.P.

2002-01-01

media, obtained with different scanning systems and sample sizes, to illustrate advantages and limitations of these various systems, including topics of spatial resolution and contrast. In addition, we present examples of our most recent three-dimensional high-resolution images, for which......A combination of advances in experimental techniques and mathematical analysis has made it possible to characterize phase distribution and pore geometry in porous media using non-destructive X-ray computed tomography (CT). We present qualitative and quantitative CT results for partially saturated...

Convergence analysis of a relaxed EM algorithm with uses in emission tomography

International Nuclear Information System (INIS)

Iusem, A.N.

1989-01-01

This work describes the Position Emission tomography technique this technique consists of introducing in the organism a radioactive substance and determining its concentration in each part of the body by measuring its emission in a detectors ring. (A.C.A.S.)

Recent advances in neutron tomography

International Nuclear Information System (INIS)

McFarland, E.; Massachusetts Inst. of Technology, Cambridge, MA; Lanza, R.

1993-01-01

Neutron imaging has been shown to be an excellent imaging tool for many nondestructive evaluation applications. Significantly improved contrast over X-ray images is possible for materials commonly found in engineering assemblies. The major limitations have been the neutron source and detection. A low cost, position sensitive neutron tomography detector system has been designed and built based on an electro-optical detector system using a LiF-ZnS scintillator screen and a cooled charge coupled device. This detector system can be used for neutron radiography as well as two and three-dimensional neutron tomography. Calculated performance of the system predicted near-quantum efficiency for position sensitive neutron detection. Experimental data was recently taken using this system at McClellan Air Force Base, Air Logistics Center, Sacramento, CA. With increased availability of low cost neutron sources and advanced image processing, neutron tomography will become an increasingly important nondestructive imaging method

Value of computed tomography and magnetic resonance imaging in diagnosis of central nervous system

International Nuclear Information System (INIS)

Walecka, I.; Sicinska, J.; Szymanska, E.; Rudnicka, L.; Furmanek, M.; Walecki, J.; Olszewska, M.; Rudnicka, L.; Walecki, J.

2006-01-01

Systemic sclerosis is an autoimmune connective tissue disease characterized by vascular abnormalities and fibrotic changes in skin and internal organs. The aim of the study was to investigate involvement of the central nervous system in systemic sclerosis and the value of computed tomography (CT) and magnetic resonance imaging (MRI) in evaluation of central nervous system involvement in systemic sclerosis. 26 patients with neuropsychiatric symptoms in the course of systemic sclerosis were investigated for central nervous system abnormalities by computed tomography (CT) and magnetic resonance imaging (MRI). Among these 26 symptomatic patients lesions in brain MRI and CT examinations were present in 54% and in 50% patients respectively. Most common findings (in 46% of all patients), were symptoms of cortical and subcortical atrophy, seen in both, MRI and CT. Single and multiple focal lesions, predominantly in the white matter, were detected by MRI significantly more frequently as compared to CT (62% and 15% patients respectively). These data indicate that brain involvement is common in patients with severe systemic sclerosis. MRI shows significantly higher than CT sensitivity in detection focal brain lesions in these patients. (author)

Computed tomography

International Nuclear Information System (INIS)

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

1994-01-01

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

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)

An EM System With Dramatic Multi-Axis Transmitter and Tensor Gradiometer Receiver

Science.gov (United States)

2011-06-01

Thus, the main difference between the spatial behavior of target anomalies measured with a magnetometer and those we measured with an EM system is in...current efforts include the development of tensor magnetic gradiometers based on triaxial fluxgate technology by the USGS (Snyder & Bracken, Development...Superconducting gradiometer/ Magnetometer Arrays and a Novel Signal Processing Technique. IEEE Trans. on Magnetics, MAG-11(2), 701-707. EM Tensor Gradiometer

An EM System with Dynamic Multi-Axis Transmitter and Tensor Gradiometer Receiver

Science.gov (United States)

2011-06-01

main difference between the spatial behavior of target anomalies measured with a magnetometer and those we measured with an EM system is in the nature...environmental and UXO applications, current efforts include the development of tensor magnetic gradiometers based on triaxial fluxgate technology by the USGS...Superconducting gradiometer/ Magnetometer Arrays and a Novel Signal Processing Technique. IEEE Trans. on Magnetics, MAG-11(2), 701-707. EM Tensor

Hardware Developments of an Ultrasonic Tomography Measurement System

OpenAIRE

Hudabiyah ARSHAD AMARI; Ruzairi ABDUL RAHIM; Mohd Hafiz FAZALUL RAHIMAN; Herlina ABDUL RAHIM; Muhammad Jaysuman PUSPPANATHAN

2010-01-01

This research provides new technique in ultrasonic tomography by using ultrasonic transceivers instead of using separate transmitter-receiver pair. The numbers of sensors or transducers used to acquire data plays an important role to generate high resolution tomography images. The configuration of these sensors is a crucial factor in the efficiency of data acquisition. Instead of using common separated transmitter – receiver, an alternative approach has been taken to use dual functionality ul...

A Goal Programming Model for the Siting of Multilevel EMS Systems.

Science.gov (United States)

1980-03-01

Management," unpublished Ph.D. thesis, University of Texas, Austin, Texas, 1971. -23- (11) Daskin , M. and E. Stern, " A Multiobjective Set Covering...GOAL PROGRAM4MING MODEL FOR THE SITING OF MULTILEVEL EMS SYSTE-ETC(U) UNM1AR 80 A CHARNES, J E STORBECK N000iA-75-C-569 WICLASSIFIED CCS-366 N...366 A GOAL PROGRAMMING MODEL FOR THE SITING OF MULTILEVEL EMS SYSTEMS by A . Charnes J. Storbeck March 1980 This project was partially supported by

Military Emergency Medical Service System Assessment: Application of the National Park Service Needs Assessment and Program Audit to Objectively Evaluate the Military EMS System of Okinawa, Japan.

Science.gov (United States)

Ross, Elliot M; Harper, Stephen A; Cunningham, Cord; Walrath, Benjamin D; DeMers, Gerard; Kharod, Chetan U

2017-03-01

As part of a Military Emergency Medical Services (EMS) system process improvement initiative, the authors sought to objectively evaluate the U.S. military EMS system for the island of Okinawa. They applied a program evaluation tool currently utilized by the U.S. National Park Service (NPS). A comprehensive needs assessment was conducted to evaluate the current Military EMS system in Okinawa, Japan. The NPS EMS Program Audit Worksheet was used to get an overall "score" of our assessment. After all the data had been collected, a joint committee of Military EMS physicians reviewed the findings and made formal recommendations. From 2011 to 2014, U.S. military EMS on Okinawa averaged 1,345 ± 137 patient transports annually. An advanced life support (ALS) provider would have been dispatched on 558 EMS runs (38%) based on chief complaint in 2014 had they been available. Over 36,000 man-hours were expended during this period to provide National Registry Emergency Medical Technician (EMT)-accredited instruction to certify 141 Navy Corpsman as EMT Basics. The NPS EMS Program Audit Worksheet was used and the program scored a total of 31, suggesting the program is well planned and operating within standards. This evaluation of the Military EMS system on Okinawa using the NPS program assessment and audit worksheet demonstrates the NPS evaluation instruments may offer a useful assessment tool for the evaluation of Military EMS systems. Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.

Computerized tomography using high resolution X-ray imaging system with a microfocus source

International Nuclear Information System (INIS)

Zaprazny, Z.; Korytar, D.; Konopka, P.; Ac, V.; Bielecki, J.

2011-01-01

In recent years there is an effort to image an internal structure of an object by using not only conventional 2D X-ray radiography but also using high resolution 3D tomography which is based on reconstruction of multiple 2D projections at various angular positions of the object. We have previously reported [1] the development and basic parameters of a high resolution x-ray imaging system with a microfocus source. We report the recent progress using this high resolution X-ray laboratory system in this work. These first findings show that our system is particularly suitable for light weight and nonmetallic objects such as biological objects, plastics, wood, paper, etc. where phase contrast helps to increase the visibility of the finest structures of the object. Phase-contrast X-ray Computerized Tomography is of our special interest because it is an emerging imaging technique that can be implemented at third generation synchrotron radiation sources and also in laboratory conditions using a microfocus X-ray tube or beam conditioning optics. (authors)

Radon space techniques for the evaluation of industrial tomography systems

International Nuclear Information System (INIS)

Burge, R.E.; Wombell, R.J.; Belchamber, R.M.; Betteridge, D.; Lilley, T.

1987-01-01

Computerised tomography (CT) is a powerful tool in medicine, and would be well suited to a wide range of industrial applications, particularly non-destructive testing. However, the very diversity of uses makes the production of a standardised scanner impossible. Systems for an industrial use will have to be designed with a problem in mind. An approach is presented for the analysis of CT scanning systems to help in the design problem. It first describes a system in terms of the sampling of the Radon transform of the object and then uses this information to produce a spatial description of the performance of a scanning system in terms of data collection. This description is called a resolution map and it is shown how the resolution map can be related to the object under study. (author)

System Matrix Analysis for Computed Tomography Imaging

Science.gov (United States)

Flores, Liubov; Vidal, Vicent; Verdú, Gumersindo

2015-01-01

In practical applications of computed tomography imaging (CT), it is often the case that the set of projection data is incomplete owing to the physical conditions of the data acquisition process. On the other hand, the high radiation dose imposed on patients is also undesired. These issues demand that high quality CT images can be reconstructed from limited projection data. For this reason, iterative methods of image reconstruction have become a topic of increased research interest. Several algorithms have been proposed for few-view CT. We consider that the accurate solution of the reconstruction problem also depends on the system matrix that simulates the scanning process. In this work, we analyze the application of the Siddon method to generate elements of the matrix and we present results based on real projection data. PMID:26575482

Tomography of positrons with SPECT systems

International Nuclear Information System (INIS)

Isoardi, Roberto A.

1999-01-01

The tomography for emissions of positrons (PET) demonstrate the clinical uses to provide information in the area of neurology, cardiology and principally, in oncology. This chapter describes the principles of the functioning and instrumentation, clinical applications and the state of the art

Man-Portable Simultaneous Magnetometer and EM System (MSEMS)

Science.gov (United States)

2008-12-01

limited to cesium vapor magnetometers outputting a Larmor signal. It cannot, as presently configured, be used with less expensive fluxgate magnetometers ...pulses to convert the frequency-based Larmor signal into nT. A fluxgate magnetometer does not employ the resonance mechanism of an alkali vapor...Simultaneous Magnetometer and EM System (MSEMS) December 2008 Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden for the

Small scale imaging using ultrasonic tomography

International Nuclear Information System (INIS)

Zakaria, Z.; Abdul Rahim, R.; Megat Ali, M.S.A.; Baharuddin, M.Y.; Jahidin, A.H.

2009-01-01

Ultrasound technology progressed through the 1960 from simple A-mode and B-mode scans to today M-mode and Doppler two dimensional (2-D) and even three dimensional (3-D) systems. Modern ultrasound imaging has its roots in sonar technology after it was first described by Lord John Rayleigh over 100 years ago on the interaction of acoustic waves with media. Tomography technique was developed as a diagnostic tool in the medical area since the early of 1970s. This research initially focused on how to retrieve a cross sectional images from living and non-living things. After a decade, the application of tomography systems span into the industrial area. However, the long exposure time of medical radiation-based method cannot tolerate the dynamic changes in industrial process two phase liquid/ gas flow system. An alternative system such as a process tomography systems, can give information on the nature of the flow regime characteristic. The overall aim of this paper is to investigate the use of a small scale ultrasonic tomography method based on ultrasonic transmission mode tomography for online monitoring of liquid/ gas flow in pipe/ vessel system through ultrasonic transceivers application. This non-invasive technique applied sixteen transceivers as the sensing elements to cover the pipe/ vessel cross section. The paper also details the transceivers selection criteria, hardware setup, the electronic measurement circuit and also the image reconstruction algorithm applied. The system was found capable of visualizing the internal characteristics and provides the concentration profile for the corresponding liquid and gas phases. (author)

Simulation of quantum systems by the tomography Monte Carlo method

International Nuclear Information System (INIS)

Bogdanov, Yu I

2007-01-01

A new method of statistical simulation of quantum systems is presented which is based on the generation of data by the Monte Carlo method and their purposeful tomography with the energy minimisation. The numerical solution of the problem is based on the optimisation of the target functional providing a compromise between the maximisation of the statistical likelihood function and the energy minimisation. The method does not involve complicated and ill-posed multidimensional computational procedures and can be used to calculate the wave functions and energies of the ground and excited stationary sates of complex quantum systems. The applications of the method are illustrated. (fifth seminar in memory of d.n. klyshko)

An automated blood sampling system used in positron emission tomography

International Nuclear Information System (INIS)

Eriksson, L.; Bohm, C.; Kesselberg, M.

1988-01-01

Fast dynamic function studies with positron emission tomography (PET), has the potential to give accurate information of physiological functions of the brain. This capability can be realised if the positron camera system accurately quantitates the tracer uptake in the brain with sufficiently high efficiency and in sufficiently short time intervals. However, in addition, the tracer concentration in blood, as a function of time, must be accurately determined. This paper describes and evaluates an automated blood sampling system. Two different detector units are compared. The use of the automated blood sampling system is demonstrated in studies of cerebral blood flow, in studies of the blood-brain barrier transfer of amino acids and of the cerebral oxygen consumption. 5 refs.; 7 figs

An X-Ray computed tomography/positron emission tomography system designed specifically for breast imaging.

Science.gov (United States)

Boone, John M; Yang, Kai; Burkett, George W; Packard, Nathan J; Huang, Shih-ying; Bowen, Spencer; Badawi, Ramsey D; Lindfors, Karen K

2010-02-01

Mammography has served the population of women who are at-risk for breast cancer well over the past 30 years. While mammography has undergone a number of changes as digital detector technology has advanced, other modalities such as computed tomography have experienced technological sophistication over this same time frame as well. The advent of large field of view flat panel detector systems enable the development of breast CT and several other niche CT applications, which rely on cone beam geometry. The breast, it turns out, is well suited to cone beam CT imaging because the lack of bones reduces artifacts, and the natural tapering of the breast anteriorly reduces the x-ray path lengths through the breast at large cone angle, reducing cone beam artifacts as well. We are in the process of designing a third prototype system which will enable the use of breast CT for image guided interventional procedures. This system will have several copies fabricated so that several breast CT scanners can be used in a multi-institutional clinical trial to better understand the role that this technology can bring to breast imaging.

Similarity-regulation of OS-EM for accelerated SPECT reconstruction

Science.gov (United States)

Vaissier, P. E. B.; Beekman, F. J.; Goorden, M. C.

2016-06-01

Ordered subsets expectation maximization (OS-EM) is widely used to accelerate image reconstruction in single photon emission computed tomography (SPECT). Speedup of OS-EM over maximum likelihood expectation maximization (ML-EM) is close to the number of subsets used. Although a high number of subsets can shorten reconstruction times significantly, it can also cause severe image artifacts such as improper erasure of reconstructed activity if projections contain few counts. We recently showed that such artifacts can be prevented by using a count-regulated OS-EM (CR-OS-EM) algorithm which automatically adapts the number of subsets for each voxel based on the estimated number of counts that the voxel contributed to the projections. While CR-OS-EM reached high speed-up over ML-EM in high-activity regions of images, speed in low-activity regions could still be very slow. In this work we propose similarity-regulated OS-EM (SR-OS-EM) as a much faster alternative to CR-OS-EM. SR-OS-EM also automatically and locally adapts the number of subsets, but it uses a different criterion for subset regulation: the number of subsets that is used for updating an individual voxel depends on how similar the reconstruction algorithm would update the estimated activity in that voxel with different subsets. Reconstructions of an image quality phantom and in vivo scans show that SR-OS-EM retains all of the favorable properties of CR-OS-EM, while reconstruction speed can be up to an order of magnitude higher in low-activity regions. Moreover our results suggest that SR-OS-EM can be operated with identical reconstruction parameters (including the number of iterations) for a wide range of count levels, which can be an additional advantage from a user perspective since users would only have to post-filter an image to present it at an appropriate noise level.

Computerized tomography data on CNS affection in systemic lupus erythematosus

International Nuclear Information System (INIS)

Ivanova, M.M.; Bliznyuk, O.I.; Todua, F.I.; Tumanova, A.A.

1989-01-01

Computed tomography (CT) of the brain was employed in 40 patients with systemic lupus erythematosus (SLE). Clinical cerebral pathology was obvious in 30 and absent in 10 patients. By CT cerebral symptoms were divided of 4 groups. Clinical symptom complexes of CNS defects and SLE were reflected on definite CT images correlated with focal damage to the brain. CT picture of enlarged subarachnoid space, ventricles and basal cisterns can be observed in SLE patients without neurological symptoms. This indicated likely subclinical cerebral affection

Progressive systemic sclerosis: high-resolution computed tomography findings; Esclerose sistemica progressiva: aspectos na tomografia computadorizada de alta resolucao

Energy Technology Data Exchange (ETDEWEB)

Gasparetto, Emerson L.; Pimenta, Rodrigo; Ono, Sergio E.; Escuissato, Dante L. [Parana Univ., Curitiba, PR (Brazil). Hospital de Clinicas. Servico de Radiologia Medica]. E-mail: dante.luiz@onda.com.br; Inoue, Cesar [Parana Univ., Curitiba, PR (Brazil). Faculdade de Medicina

2005-09-15

Objective: To describe the high-resolution computed tomography findings in the lung of patients with systemic sclerosis, independently of the respiratory symptoms. Materials and methods: Seventy-three high-resolution computed tomography scans of 44 patients with clinical diagnosis of systemic sclerosis were reviewed and defined by the consensus of two radiologists. Results: Abnormalities were seen in 91.8% (n = 67) of the scans. The most frequent findings were reticular pattern (90.4%), ground-glass opacities (63%), traction bronchiectasis and bronchiolectasis (56.2%), esophageal dilatation (46.6%), honeycombing pattern (28.8%) and signs of pulmonary hypertension (15.6%). In most cases the lesions were bilateral (89%) and symmetrical (58.5%). The lesions were predominantly located in the basal (91.2%) and peripheral (92.2%) regions. Conclusion: In the majority of the patients, progressive systemic sclerosis can cause pulmonary fibrosis mainly characterized by reticular pattern with basal and peripheral distribution on high-resolution computed tomography. (author)

Metal-induced streak artifact reduction using iterative reconstruction algorithms in x-ray computed tomography image of the dentoalveolar region.

Science.gov (United States)

Dong, Jian; Hayakawa, Yoshihiko; Kannenberg, Sven; Kober, Cornelia

2013-02-01

The objective of this study was to reduce metal-induced streak artifact on oral and maxillofacial x-ray computed tomography (CT) images by developing the fast statistical image reconstruction system using iterative reconstruction algorithms. Adjacent CT images often depict similar anatomical structures in thin slices. So, first, images were reconstructed using the same projection data of an artifact-free image. Second, images were processed by the successive iterative restoration method where projection data were generated from reconstructed image in sequence. Besides the maximum likelihood-expectation maximization algorithm, the ordered subset-expectation maximization algorithm (OS-EM) was examined. Also, small region of interest (ROI) setting and reverse processing were applied for improving performance. Both algorithms reduced artifacts instead of slightly decreasing gray levels. The OS-EM and small ROI reduced the processing duration without apparent detriments. Sequential and reverse processing did not show apparent effects. Two alternatives in iterative reconstruction methods were effective for artifact reduction. The OS-EM algorithm and small ROI setting improved the performance. Copyright © 2012 Elsevier Inc. All rights reserved.

Axial Tomography from Digitized Real Time Radiography

Science.gov (United States)

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

1985-01-18

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

EMS applications integration in a SCADA; Integracion de aplicaciones EMS en un SCADA

Energy Technology Data Exchange (ETDEWEB)

Roses, Rodolfo; Colome, D.G.; Orduna, E.; Vega, C. de la; Camisay, G. [Universidad Nacional de San Juan (Argentina). Inst. de Energia Electrica]. E-mail: roses@iee.unsj.edu.ar

2001-07-01

This paper presents the methodology to integrate EMS (Energy Management System) functions in a SCADA system (System Control and Data Acquisition). The implementation methodology of the EMS applications has included the design and database implementation, EMS-SCADA communication, results presentation, logics definition of execution and processing ways. The applications portability characteristics allow integration with different SCADA system with some adaptations on the data communication interface. Thus, a open system has been obtained and implemented successfully in the control center of an Argentine 132 kV network.

Brain dopaminergic systems : imaging with positron tomography

Energy Technology Data Exchange (ETDEWEB)

Baron, J C [University of Caen/INSERM U, Caen (France). CYCERON; Comar, D [E.E.C. Concerted Action on P.E.T. Investigations of Cellular Regeneration and Degeneration, Orsay (France) CEA, 91 - Orsay (France). Service Hospitalier Frederic Joliot; Farde, L [Karolinska Sjukhuset, Stockholm (Sweden); Martinot, J L; Mazoyer, B [CEA, 91 - Orsay (France). Service Hospitalier Frederic Joliot Paris-

1991-01-01

Imaging of the dopaminergic system in the human brain with the in vivo use of Positron Emission Tomography emerged in the late 1980s as a tool of major importance in clinical neurosciences and pharmacology. The last few years have witnessed rapid development of new radiotracers specific to receptors, reuptake sites and enzymes of the dopamine system; the application of these radiotracers has led to major break-troughs in the pathophysiology and therapy of movement disorders and schizophrenic-like psychoses. This book is the first to collect, in a single volume, state-of-the-art contributions to the various aspects of this research. Its contents address methodological issues related to the design, labelling, quantitative imaging and compartmental modeli-sation of radioligands of the post-synaptic, pre-synaptic and enzyme sites of the dopamine system and to their use in clinical research in the fields of Parkinson's disease as well as other movement disorders, psychoses and neuroleptic receptor occupancy. The chapters were written by leading European scientists in the field of PET, gathered together in Caen (France, November 1990) under the aegis of the EEC Concerted Action on PET Investigations of Cellular Regeneration and Degeneration. This book provides a current and comprehensive overview on PET studies of the brain dopamine system which should aid and interest neurologists , psychiatrists, pharmacologists and medical imaging scientists. (author). refs.; figs.; tabs.

Orbital parameters of the multiple system EM Boo

Science.gov (United States)

Özkardeş, B.; Bakış, H.; Bakış, V.

2018-02-01

EM Boo is a relatively bright (V = 8.98 mag.) and short orbital period (P⁓2.45 days) binary star member of the multiple system WDS J14485+2445AB. There is neither photometric nor spectroscopic study of the system in the literature. In this work, we obtained spectroscopic orbital parameters of the system from new high resolution spectroscopic observations made with échelle spectrograph attached to UBT60 telescope of Akdeniz University. The spectroscopic solution yielded the values K1 = 100.7±2.6 km/s, K2 = 120.1±2.6 km/s and Vγ = -14.6±3.1 km/s, and thus the mass ratio of the system q = 0.838±0.064.

Optical coherence tomography-enhanced microlaryngoscopy: preliminary report of a noncontact optical coherence tomography system integrated with a surgical microscope.

Science.gov (United States)

Vokes, David E; Jackson, Ryan; Guo, Shuguang; Perez, Jorge A; Su, Jianping; Ridgway, James M; Armstrong, William B; Chen, Zhongping; Wong, Brian J F

2008-07-01

Optical coherence tomography (OCT) is a new imaging modality that uses near-infrared light to produce cross-sectional images of tissue with a resolution approaching that of light microscopy. We have previously reported use of OCT imaging of the vocal folds (VFs) during direct laryngoscopy with a probe held in contact or near-contact with the VFs. This aim of this study was to develop and evaluate a novel OCT system integrated with a surgical microscope to allow hands-free OCT imaging of the VFs, which could be performed simultaneously with microscopic visualization. We performed a prospective evaluation of a new method of acquiring OCT images of the VFs. An OCT system was successfully integrated with a surgical microscope to permit noncontact OCT imaging of the VFs of 10 patients. With this novel device we were able to identify VF epithelium and lamina propria; however, the resolution was reduced compared to that achieved with the standard contact or near-contact OCT. Optical coherence tomography is able to produce high-resolution images of vocal fold mucosa to a maximum depth of 1.6 mm. It may be used in the diagnosis of VF lesions, particularly early squamous cell carcinoma, in which OCT can show disruption of the basement membrane. Mounting the OCT device directly onto the operating microscope allows hands-free noncontact OCT imaging and simultaneous conventional microscopic visualization of the VFs. However, the lateral resolution of the OCT microscope system is 50 microm, in contrast to the conventional handheld probe system (10 microm). Although such images at this resolution are still useful clinically, improved resolution would enhance the system's performance, potentially enabling real-time OCT-guided microsurgery of the larynx.

High resolution computed tomography in patients with various forms of systemic sclerosis

International Nuclear Information System (INIS)

Lewszuk, A.; Rozycki, J.; Tarasow, E.; Kowal-Bielecka, O.

2008-01-01

Pulmonary lesions are, besides renal and cardiac complications, one of the main causes of mortality among patients with systemic sclerosis (scleroderma). Pathologic changes in the respiratory system take the form of interstitial fibrosis clinically manifested by progressive exertion dyspnea and abnormalities of respiratory restriction type in functional tests. The aim of the study was systematization of pulmonary lesion symptomatology in conventional chest radiography and high resolution computed tomography (HRCT) in patients with various forms of scleroderma, as well as determination of the frequency and localization of the particular lesion types. The study was carried out in a group of 49 patients with systemic sclerosis (47 women and 2 men), who underwent conventional radiography and high resolution computed tomography of the chest. In patients with systemic sclerosis, HRCT revealed most frequently interstitial changes of ground glass type, as well as linear and reticular opacities, whereas bronchiectasis and honeycombing type lesions were less frequent. Pulmonary lesions were seen with increasing frequency towards the lung base and were localized mainly in the posterior, inferior and peripheral parts of the lungs. Comparison of the patients with limited and diffuse scleroderma demonstrated that the diffuse form is associated with more frequent involvement of the respiratory system and more advanced pulmonary lesions. The observed characteristics of pulmonary lesions show similarity between interstitial lung disease in the course of systemic sclerosis and nonspecific interstitial pneumonia (NSIP), which supports classification of interstitial lung disease associated with scleroderma as belonging to that group of interstitial inflammations. (author)

Characteristics of the neutron and X-ray tomography system at the SANRAD facility in South Africa

International Nuclear Information System (INIS)

Beer, F.C. de

2005-01-01

Through collaboration with the NEUTRA-facility at the Paul Scherrer Institute (PSI), Switzerland, a turnkey tomography system was designed specifically for the beam geometry at the South African Neutron Radiography (SANRAD) facility, located on the beam port floor of the SAFARI-1 nuclear research reactor and operated by Necsa. The new system is currently being extensively utilized in both 2D and 3D mode for various applications in general industry and institutional activities. The basic performance characteristics of its 3D tomography capability in a neutron and X-ray configuration are presented with the aid of several case studies. An X-ray source has also been commissioned to further diversify the capabilities of the facility

Evaluation of <em>HER2em> Gene Amplification in Breast Cancer Using Nuclei Microarray <em>in em>S>itu em>Hybridization

Directory of Open Access Journals (Sweden)

Xuefeng Zhang

2012-05-01

Full Text Available Fluorescence<em> em>>in situ em>hybridization (FISH assay is considered the “gold standard” in evaluating <em>HER2/neu (HER2em> gene status. However, FISH detection is costly and time consuming. Thus, we established nuclei microarray with extracted intact nuclei from paraffin embedded breast cancer tissues for FISH detection. The nuclei microarray FISH (NMFISH technology serves as a useful platform for analyzing <em>HER2em> gene/chromosome 17 centromere ratio. We examined <em>HER2em> gene status in 152 cases of invasive ductal carcinomas of the breast that were resected surgically with FISH and NMFISH. <em>HER2em> gene amplification status was classified according to the guidelines of the American Society of Clinical Oncology and College of American Pathologists (ASCO/CAP. Comparison of the cut-off values for <em>HER2em>/chromosome 17 centromere copy number ratio obtained by NMFISH and FISH showed that there was almost perfect agreement between the two methods (κ coefficient 0.920. The results of the two methods were almost consistent for the evaluation of <em>HER2em> gene counts. The present study proved that NMFISH is comparable with FISH for evaluating <em>HER2em> gene status. The use of nuclei microarray technology is highly efficient, time and reagent conserving and inexpensive.

Neonatal Phosphate Nutrition Alters <em>in em>Vivo> and <em>in em>Vitro> Satellite Cell Activity in Pigs