Cerebral angiography using Fuji computed radiography (FCR) system
International Nuclear Information System (INIS)
Eighty-seven subtraction images of FCR were compared with subtraction images of conventional angiography. Although FCR images with reduced exposure dose (25 % of regular dose) and with diluted contrast material (150 mgI/ml, 50 % of usual concentration) were slightly inferior to the images of conventional angiography, most clinically important vessels were adequately visualized. As FCR has wider dynamic range and higher contrast resolution than conventional angiography, FCR may take over conventional angiography. (author).
1985-01-01
Clinical evaluations of intra-arterial subtraction angiography using Fuji computed radiography
International Nuclear Information System (INIS)
Intra-arterial subtraction angiography(IADSA) using Fuji computed radiography(FCR) was performed on 130 patients with cervical, pelvic, peripheral and abdominal diseases. It was compared with conventional angiography(radiographs produced by combining photographic film with an intensifying screen) performed on same patients. Radiographs produced by FCR were better than conventional radiographs in cervical, pelvic and peripheral angiography. In the abdominal angiography using FCR, there was misregistration artifact in some cases, but in hepatic angiography, the new radiographs under the injection of small amount of contrast medium(about 10ml) and the short exposure duration(about 10 seconds) were excellent. It was as valuable as conventional angiography (infusion hepatic angiography) for diagnosing hepatic neoplasms. ...
1985-01-01
Transbrachial arterial digital subtraction angiography
International Nuclear Information System (INIS)
27 cases including 7 outpatients, underwent intraarterial DSA using 4-F nylon catheter, by transbrachial arterial approach. Much of DSAs were performed in Fuji Computed Radiography (FCR), which has high spatial resolution. In all cases, image quality satisfied clinical demands. No major complication occured in this series. Transbrachial arterial digital subtraction angiography is excellent and safe method for screening of vascular disease. (author).
1985-01-01
Energy Technology Data Exchange (ETDEWEB)
Intravenous digital subtraction angiography using Fuji computed radiography system (FCR-DSA) was used to evaluate 57 preoperative patients with clinical manifestations of peripheral vascular disease of lower extremity. With its high contrast resolution and good special resolution, image of FCR-DSA could offer optimal information of vascular abnormality in lower extremity distal to midfoot for the diagnosis and the choice of management.
1987-03-01
International Nuclear Information System (INIS)
Intravenous digital subtraction angiography using Fuji computed radiography system (FCR-DSA) was used to evaluate 57 preoperative patients with clinical manifestations of peripheral vascular disease of lower extremity. With its high contrast resolution and good special resolution, image of FCR-DSA could offer optimal information of vascular abnormality in lower extremity distal to midfoot for the diagnosis and the choice of management. (orig.).
1987-01-01
Angiography of the head using Fuji computed radiography (FCR) system
International Nuclear Information System (INIS)
Forty-seven subtraction images of FCR were compared with subtraction images of conventional angiography of the head. Quality of the FCR images were equal or superior to that of conventional angiography. Antero-posterior projection of external carotid arteriography by FCR was most useful because of its wide dynamic range. As contrast resolution of FCR is superior to that of conventional angiography, only half diluted contrast media was needed. As for spacial resolution, FCR is slightly inferior to conventional angiography. However, most vessels which are clinically important were adequately demonstrated. A weak point of FCR which should be improved is relatively long time to process the images after radiation exposure. (author).
1985-01-01
A computer-assisted method for 3D subtraction angiography based on spiral CT
International Nuclear Information System (INIS)
The objective of this study was to develop a method for 3D subtraction CT angiography and to optimize the visualization after semiautomatic segmentation. Ten patients with aneurysms of the abdominal aorta were examined using spiral CT. To reconstruct the vessels, as well as adjacent organs such as the liver and kidneys, one image data volume was acquired before and after injection of the contrast agent. The CT scans were obtained with a Siemens Somatom Plus 4. To improve the results of automatic segmentation, as well as visualization by maximum intensity projection (i.e. removal of bony structures), subtraction of both image volumes is necessary. However, small translation shifts disturb the subtraction process and produce artificial contours. To calculate the disparities along the three coordinate axes of two corresponding image volumes, a cepstrum filter is applied to a pair of image volumes. After ...
Somatic and genetic radiation exposure of the patient in digital subtraction angiography (DSA)
International Nuclear Information System (INIS)
The somatic and genetic radiation exposure of patients undergoing Digital Subtraction Angiography (DSA) and traditional Film Arteriography (FA) of cranial, cervical, thoracic and abdominal vascular territories are compared. The radiation doses absorbed within the critical organs - red bone marrow, lung, thyroid gland and female breast - and in the gonads were measured using an anthropomorphic Alderson phantom. A Somatic Dose Index was calculated in order to estimate the somatic radiation risk. The somatic radiation exposure depends upon the location of the critical organs with respect to the entrance site of the x-ray beam, and can be reduced by an appropriate choice of the angiographic projection. Under this condition, the radiation exposure of the patient during DSA can be lower than during FA. For renal DSA an a.p. projection, the use of an abdominal compression device and careful caudal shielding of the field are advocated. (orig.).
1986-01-01
Digital subtraction angiography with scanning lazer stimulated luminescence
International Nuclear Information System (INIS)
Fuji Computed Radiography (FCR) utilizes imaging plates of scanning lazer stimulated luminescence. FCR can be used for intravenous digital subtraction angiography (IVDSA) and for intraarterial studies because of tis high contrast and spatial resolution. Pixel size of the imaging plates for angiography is 0.2 mm. Experimentally, it could demonstrate a vessel 1 mm in diameter with a contrast of 0.1, when opacified with a contrast medium of 3 % iodine concentration, and could image a vessel 3 mm in diameter with contrast of 0.1, when opacified with 1 % contrast medium. A 20 % stenosed portion of a vessel 3 mm in diameter was identified when opacified with 3 % contrast medium, and a 20 % stenosed portion of a vessel 2 mm in diameter was identified when opacified with 10 % contrast medium. In 105 IVDSA examinations of 75 patients, FCR was superior to Digital Fluorography (DF) in spatial resolution, size of examination field, ...
1985-01-01
International Nuclear Information System (INIS)
Purpose: Three-dimensional rotational angiography (3DRA) is a new technique based on a rotational angiographic acquisition able to display arterial vessels in a 3D rendering mode. The system was mainly developed for neuroradiological evaluations but preliminary extracranial experiences have also been reported. The aim of our work was to compare the results of three-dimensional angiography of the carotid arteries done with high-flow injection of contrast medium from the aortic arch with the results of selective angiography. Materials and methods: Twenty patients underwent digital angiography of the supra-aortic vessels in order to quantify a stenosis of the carotid bifurcations previously detected at Doppler Ultrasound. Examinations were performed with the Philips Integris Allura system provided with the rotational angiography (RA) tool connected to a workstation for ...
International Nuclear Information System (INIS)
Ten patients with traumatic femoral neck fracture were studied with MR imaging (0.5 T, Magnetom, Siemens): unenhanced (multiecho, TR/TE = 1,600/30--240 [repetition time/echo time, msec]; gradient echo, TR/TE = 315/14, #theta# = 90 degrees) and Gd-DTPA enhanced (0.1 mM/kg body weight, Magnevist, Schering; gradient echo, TR/TE = 315/14, #theta# = 90 degrees). MR images were compared with clinical-radiographic findings. Digital subtraction angiography of the femoral head (FH) in five patients showed complete interruption of blood supply to the FH in three patients (signal intensity of FH did not increase on postcontrast images) and intact FH arteries in two patients (FH signal increased on postcontrast images, as did the healthy-side signal).
Digital subtraction angiography (DSA) using Fuji computed radiography (FCR)
International Nuclear Information System (INIS)
A vessel phantom suitable for evaluation of spatial and contrast resolution of FCRDSA (Fuji Computed Radiography, digital subtraction angiography) has been developed and used for determining resolution. The effects of iodine concentration, low dose exposure, and acryl thickness on the resolution were evaluated in FCRDSA, and FCRDSA images were compared with film substraction with use of this phantom. It has been proven that limitation of resolution of FCRDSA was 5 % 1 mm and about 1/4 dose exposure compared with conventional film exposure was clinically acceptable. Dye dilution method was useful to determine a program of IVDSA with imaging plate. It has been proven that time to appearance and time to peak of time-concentration curve of dye dilution method closely correlate to time to appropriate image of DSA in the neck, the chest, and the abdomen. 106 cases of IVDSA and 130 cases of IADSA using FCR in Tohoku University Hospital from January ...
1984-12-01
Noninvasive follow-up of GDC-treated saccular aneurysms by MR angiography
International Nuclear Information System (INIS)
The aim of this study was to determine sensitivity and specificity of magnetic resonance angiography (MRA) for the assessment of durable occlusion of intracranial aneurysms with Guglielmi detachable coils (GDC) and to point out the influence of MRA results in re-intervention strategies. Forty-five patients with 54 aneurysms that were previously treated by endovascular occlusion with GDC were selected for this study. All patients underwent digital subtraction angiography (DSA) and MRA examinations on the same day. The time-of-flight MRA studies were performed on a 1-T scanner. The MRA images were first read by radiologists who were not aware of the DSA results. In a second consensus reading by the neuroradiologists who had performed all interventional procedures of this series, the decision was made as to whether re-treatment was necessary. The distribution of aneurysm sizes, configurations and treatment results were ...
2001-09-01
International Nuclear Information System (INIS)
Purpose. To evaluate injection-associated pain, safety, and efficacy with the isotonic contrast medium iodixanol (Visipaque 270 mg I/ml) compared with iopromide (Ultravist 300 mg I/ml) in femoral arteriography. Methods. A multicenter, double-blind, randomized, parallel-group clinical investigation was carried out in 54 hospitals in Europe. Of the patients evaluated, 1225 received iodixanol and 1227 iopromide in conventional and/or digital subtraction angiography. Results. The iodixanol group reported statistically significantly less injection-associated pain (0.9%) than the iopromide group (9.5%) (p<0.001). Further, 4.1% in the iodixanol group experienced pain and/or severe heat sensation vs 19.8% in the iopromide group (p<0.001). In the iodixanol group, 1.8% of the patients experienced contrast-related adverse events vs 2.4% in the iopromide group (p=NS). Overall diagnostic information was optimal for 94.1% in the iodixanol group and ...
1997-07-01
Energy Technology Data Exchange (ETDEWEB)
The purpose of this study was to assess experimentally and clinically the usefulness of Fuji Computed Radiography (FCR) in angiographic examinations. FCR had a spatial resolution with much lower X-ray exposure doses, although the resolution of FCR was generally inferior to conventional films. When a contrast medium of 1% iodine concentration was used, FCR pinpointed a mass 1.5 mm in diameter; and conventional film could detect a mass 2.2 mm in diameter. The contrast of iodine in FCR examinations was stable. A high sensitivity of imaging plate allowed a wide range of visualization. In 148 selective angiographic examinatinons for 138 patients, FCR-subtraction images were superior to conventional film angiography for contrast resolution; it had a high sensitivity in detecting areas, such as the mediastimun and left lobe of the liver, and tumor stains in capillary phase. The capability of FCR arteriogram was as good as film arteriogram even with a ...
1989-06-01
International Nuclear Information System (INIS)
The purpose of this study was to assess experimentally and clinically the usefulness of Fuji Computed Radiography (FCR) in angiographic examinations. FCR had a spatial resolution with much lower X-ray exposure doses, although the resolution of FCR was generally inferior to conventional films. When a contrast medium of 1% iodine concentration was used, FCR pinpointed a mass 1.5 mm in diameter; and conventional film could detect a mass 2.2 mm in diameter. The contrast of iodine in FCR examinations was stable. A high sensitivity of imaging plate allowed a wide range of visualization. In 148 selective angiographic examinatinons for 138 patients, FCR-subtraction images were superior to conventional film angiography for contrast resolution; it had a high sensitivity in detecting areas, such as the mediastimun and left lobe of the liver, and tumor stains in capillary phase. The capability of FCR arteriogram was as good as film arteriogram even with a ...
1989-01-01
Energy Technology Data Exchange (ETDEWEB)
Hepatocellular carcinoma (HCC) is characterized by tumor vascularization from the hepatic artery. The objective of our work was to compare color Doppler ultrasonography (CDU), including power Doppler ultrasonography (PDU) with radiographic imagings with contrast medium in regard to the detection of the arterial tumor vascularity of small hepatocellular carcinomas (HCC). We examined 42 small HCC lesions 2 cm or less in diameter in 37 patients for arterial tumor vascularity by conventional CDU, PDU, dynamic computed tomography (dCT), digital subtraction angiography (DSA), and CT hepatic arteriography (CTA). Color images were detected in 25 (59.5%) and 28 (66.7%) of the 42 lesions with conventional CDU and PDU, respectively, and tumor vascularity was detected in 26 (61.9%) by dCT, 23 (54.8%) by DSA, and 29 (69.0%) by CTA. Tumor vascularity could be detected in 51.9% by PDU and CTA, more than by conventional CDU, dCT, and DSA (44.4, 44.4, and ...
2000-10-01
International Nuclear Information System (INIS)
The EXAFS-study (Fe, Sn and Ge K-edges) of disordered by mechanical activation binary supersaturated nanocrystalline solid solutions Fe-Al, Fe-Ge, Fe-Sn and Fe-Si is presented. The EXAFS-spectra are processed by solving the inverse binary problem, using the EXAFS-spectrum of the Fe K-edge only or combining the EXAFS-spectra on two K-edges, Fe and Ge or Fe and Sn. The parameters of partial correlation functions indicate chemical short-range ordering, high local static distortions in the lattice, increasing with metalloid content. The macrostructure of other type is forming through an initial, 'local' stage within the bcc lattice.
2007-05-21
UK PubMed Central (United Kingdom)
ObjectiveAngiography remains a critical component for diagnostic imaging and therapeutic intervention in peripheral arterial disease (PAD). The goal of this study...Full Text Available
2010-04-01
The role of interventional radiology in management of patients with end-stage renal disease
Energy Technology Data Exchange (ETDEWEB)
The aim of the paper is to review the role of interventional radiology in the management of hemodialysis vascular access and complications in renal transplantation. The evaluation of patients with hemodialysis vascular access is complex. It includes the radiology/ultrasound (US) evaluation of the peripheral veins of the upper extremities with venous mapping and the evaluation of the central vein prior to the access placement and radiological detection and treatment of the stenosis and thrombosis in misfunctional dialysis fistulas. Preoperative screening enables the identification of a suitable vessel to create a hemodynamically-sound dialysis fistula. Clinical and radiological detection of the hemodynamically significant stenosis or occlusion demands fistulography and endovascular treatment. Endovascular prophylactic dilatation of stenosis greater than 50% with associated clinical abnormalities such as flow-rate reduction is warranted to prolong access patency. The technical success ...
2003-05-01
K-edge X-ray absorption spectra of argon in sputtered aluminum films
International Nuclear Information System (INIS)
We have measured K-edge X-ray absorption spectra of argon in sputtered aluminum films at a synchrotron radiation facility (the Photon Factory). We found that the energy and shape of white line change when the film is annealed at 500 C and the spectrum becomes resembling that of argon implanted in silicon. From the analyses of the X-ray absorption spectra and TEM observation we concluded that argon exists as very small atom clusters with a diameter less than 1 nm or exist as isolated atoms in the as-sputtered aluminum film, and that the size of the clusters become as big as 10 nm diameter when the film is heated. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)
1999-01-04
Tracheal images using energy subtraction Fuji computed radiography
International Nuclear Information System (INIS)
Twenty patients with lesions in the trachea or bronchus underwent energy subtraction Fuji computed radiography (FCR). Images obtained were compared with those from conventional FCR (plain FCR). ''Very clear'' images (in which the contour of the trachea and bronchus could be clearly defined) were obtained in 12/22 (55 %) by energy subtraction FCR and in 3/22 (14 %) by plain FCR; ''clear'' images (in which the contour could be defined) in 9/22 (41 %) by energy subtraction FCR and in 18/22 (82 %) by plain FCR; and ''unclear'' images (in which the contour could not be defined) in 1/22 (5 %) by both methods. Energy subtraction FCR, as well as plain FCR, yielded high image quality for the trachea. Energy subtraction FCR was superior to plain films when tumors existed within the trachea. (Namekawa, K.).
1985-01-01
Angiography in dibuthylnitrosamine-induced rat bladder tumours
International Nuclear Information System (INIS)
(1972). Denmark Ekelund, L. Goethlin, J. Henrikson, H. Letter-to-the-
Energy Technology Data Exchange (ETDEWEB)
Purpose: To evaluate the success rates of the implantation of stent grafts in the treatment of peripheral aneurysms. Materials and methods: in 13 patients with 15 aneurysms at the common iliac artery (n = 6), external iliac artery (n = 1), hypogastric artery (n = 2), femoral artery (n = 2) or popliteal artery (n = 4), implantation of dacron-covered nitinol stents was performed. The patients were followed up for three to 20 months (mean, 8.8 months) with intravenous digital subtraction angiography, CT or colour-coded Doppler sonography. Results: In all cases, the aneurysm was successfully occluded after stent implantation. In one case with a popliteal aneurysm, kinking of the vessel caused thrombosis of the stent. The stent was successfully reopened. The aneurysm however, had to be surgically treated 9 months later. The primary and secondary patency rates at 6 months were 93% and 100%, respectively. Conclusion: The method described might be an ...
1998-03-01
3D rotational angiography: Benefits obtained in clinical endovascular treatments
International Nuclear Information System (INIS)
The application of 3D rotational angiography marks a breakthrough in endovascular treatment of aneurysmas of the brain. 3D images are produced based on image series obtained by rotational angiography, so that the anatomic details of interest can be visualized from any requested angle. (orig./CB)
1999-01-01
Resolution enhancement by subtraction of confocal signals taken at different pinhole sizes.
Subtractive imaging in confocal fluorescence light microscopy is based on the subtraction of a suitably weighted widefield image from a confocal image. An approximation to a widefield image can be obtained by detection with an opened confocal pinhole. The subtraction of images enhances the resolution in-plane as well as along the optic axis. Due to the linearity of the approach, the effect of subtractive imaging in Fourier-space corresponds to a reduction of low spatial frequency contributions leading to a relative enhancement of the high frequencies. Along the direction of the optic axis this also results in an improved sectioning. Image processing can achieve a similar effect. However, a 3D volume dataset must be acquired and processed, yielding a result essentially identical to subtractive imaging but superior in signal-to-noise ratio. The latter can be increased further with the ...
2003-01-01
International Nuclear Information System (INIS)
The local environment of Ca dopants in barium titanate, BaTiO_3, is investigated by Ca K-edge X-ray absorption near-edge structure (XANES) spectroscopy. In conjunction with experiments, first-principles calculations by two methods are systematically made. The projector-augmented wave (PAW) method is used to optimize the local structure and obtain the formation energy. The augmented plane wave plus local orbitals method is adopted to obtain theoretical XANES spectra. A comparison between experimental and theoretical XANES spectra shows that Ca dopants are located at the Ba"2"+ sites forming Ca"2"+. Formation energy calculations of Ca doped BaTiO_3 by the PAW method also give the same results. The Ca atom in BaTiO_3 is off-centering in comparison with the Ba site in BaTiO_3. The off-centering of Ca atom is newly revealed by the combination of XANES spectroscopy and first-principles DFT calculations.
2010-06-01
We present an x-ray magnetic circular dichroism (XMCD) study performed on both Ho{sub 6}Fe{sub 23} and Y{sub 6}Fe{sub 23} compounds as a function of the temperature. The combined analysis of both Fe K-edge and Ho L{sub 2,3}-edge XMCD spectra recorded through the magnetic compensation transition allows us to disentangle the thermal dependence of both Fe and Ho magnetic moments in Ho{sub 6}Fe{sub 23}. In addition, contributions from Ho ions to the Fe K-edge XMCD signals and, conversely, from Fe ions to the Ho L{sub 2,3}-edge XMCD spectra have been clearly identified. These extra contributions, arising from the strong Fe(3d)-Ho(5d) hybridization, have been isolated from the spectra and correlated with the magnetic state of both Ho and Fe ions surrounding the absorbing site. The influence of these contributions to the values of the orbital and spin moments derived by using sum rule analysis is also shown.
2005-09-01
Interpretation of EXAFS data from laser shock compressed plasmas
Energy Technology Data Exchange (ETDEWEB)
Measurements on laser shock compressed aluminium using the EXAFS (Extended X-ray Absorption Fine Structure) technique on the Al K-edge are described. Two methods of analysis of this data were used for the determination of density: the standard EXAFS technique using Fourier transforms and curve fitting, and a method based on a bandstructure calculation of the absorption spectra as a function of compression. These two techniques give results which are in fairly good agreement with each other and also with a hydrodynamic simulation of the experiment. The ion correlation parameter is estimated and shows that two-sided laser irradiation of aluminium foils produces a dense plasma which is strongly coupled. (author).
1989-01-01
Annealing, lattice disorder and non-Fermi liquid behavior in UCu4Pd
Energy Technology Data Exchange (ETDEWEB)
The magnetic and electronic properties of non-Fermi liquid UCu{sub 4Pd} depend on annealing conditions. Local structural changes due to this annealing are reported from UL{sub III}- and Pd K-edge x-ray absorption fine-structure measurements. In particular, annealing decreases the fraction of Pd atoms on nominally Cu 16e sites and the U-Cu pair-distance distribution width. This study provides quantitative information on the amount of disorder in UCu{sub 4Pd} and allows an assessment of its possible importance to the observed non-Fermi liquid behavior.
2002-07-30
Aphakic macular oedema following prosthetic lens implantation.
UK PubMed Central (United Kingdom)
Fluorescein angiography of the iris was performed on patients with plastic lens implants with cystoid oedema of the macula, and the nature of the vascular changes was compared with controls provided...Full Text Available
1977-05-01
Energy Technology Data Exchange (ETDEWEB)
Purpose: The aim of this study was to test the feasibility of iliac artery stent placement under MR guidance with real-time MR radial scanning in an animal model. Materials and methods: The experiments were performed on three pigs in a 1.5 T scanner. Radial scanning with a gradient echo technique (T{sub R} 8.4 ms, T{sub E} 3.6 ms, flip angle 10 ) was used. A dedicated backprojector performed the reconstruction of the raw data in real-time. The resulting MR-images were displayed on LCD screens beside the magnet. The sliding window reconstruction technique allowed image acquistion at a frame rate of 16 images per second. MR-compatible self-expanding stents with a diameter of 8 mm and a length of 3 cm were placed into the left iliac artery. Their positions were verified by digital subtraction angiography (DSA) and compared to MRI. Results: All stents were successfully placed. Stent positions as monitored by real-time MR were identical to those ...
1998-12-01
Net energy output from harvesting small-diameter trees using a ...
Sep 1, 2011 ... Description: What amount of extra energy can be generated after subtracting the total energy consumed to produce the biomass energy? ...
Angiography in the diagnosis and treatment of trauma
Energy Technology Data Exchange (ETDEWEB)
Angiography plays a vital role in the investigation of the patient suffering from multiple trauma. The commonest injuries have been rupture of the thoracic aorta, renal lacerations, arterial bleeding associated with fractures and soft-tissue injuries to the pelvis, and occlusions of the arteries supplying the limbs. Transcatheter arterial embolization may be the definitive therapeutic procedure in pelvic bleeding.
1983-09-01
Clinical application of dual energy subtraction in direct digital radiography of chest
International Nuclear Information System (INIS)
Objective: To discuss the clinical application value of dual energy subtraction (DES) in direct digital radiography of chest. Methods: 83 cases of chest digital radiography(DR) using double-energy subtraction (DES) were randomly selected, and three posterior-anterior (PA) chest films (standard image, bone image and soft tissue image) were obtained in each case, which is so called 'bone and soft tissue separated' technology. Results: With the aid of double energy subtraction (DES), the bony chest was subtracted, the sensitivity and specificity of pulmonary calcification were improved, and sensitivity of pulmonary nodes was also improved, enhancing the distinction between pulmonary benign or malignant lesions, enlightening the diagnosis of chest cage lesions, and showing a clear superiority in the detection of pulmonary nodes comparing to common chest films. The double energy ...
2009-02-01
Near-edge structures from first principles all-electron Bethe-Salpeter equation calculations
International Nuclear Information System (INIS)
We obtain x-ray absorption near-edge structures (XANES) by solving the equation of motion for the two-particle Green's function for the electron-hole pair, the Bethe-Salpeter equation (BSE), within the all-electron full-potential linearized augmented plane wave method (FPLAPW). The excited states are calculated for the Li K-edge in the insulating solids LiF, Li_2O and Li_2S, and absorption spectra are compared with independent particle results using the random phase approximation (RPA), as well as supercell calculations using the core-hole approximation within density functional theory (DFT). The binding energies of strongly bound excitations are determined in the materials, and core-exciton wavefunctions are demonstrated for LiF.
2009-03-11
Correlation of myocardial TC-99m-MIBI perfusion SPECT with coronary angiography in Namazi hospital
International Nuclear Information System (INIS)
Coronary heart disease is the leading cause of death specially among elderly. Coronary angiography is the best diagnostic method in the patients, but is unfortunately an invasive procedure with its inherent risks. Myocardial perfusion scan is a noninvasive and sensitive method for evaluation of Coronary artery disease and is suggested by many investigators in recent years. In this study, 64 patients who had a Tc99m-MIBI SPECT myocardial perfusion study at our department, underwent coronary angiography within 4 months. Correlation of the methods revealed that SPECT Tc99m -MIBI had a high sensitivity and specificity in our hand, which is comparable with international findings.
2004-04-27
Energy Technology Data Exchange (ETDEWEB)
MRT is able to demonstrate arteries while MR angiography can quantify blood flow by a non-invasive method. In the present paper blood flow measurements were carried out in four selected cases on the basis of phase mapping. In 3 patients with lesions in the pelvis or thigh, angiography was performed in order to localise the stenosis or occlusion and this was followed by qantitative blood flow measurements. The results showed that angiography may not always provide all necessary information concerning a haemodynamically significant stenosis. The method may also be used for quantifying blood flow in the renal arteries and that it has significant advantages over the colour Doppler method. (orig.).
1992-08-01
UK PubMed Central (United Kingdom)
BackgroundPatients with ST-elevation myocardial infarction (STEMI) treated with fibrinolysis are increasingly, and ever earlier, referred for routine coronary angiography and where...Full Text Available
UK PubMed Central (United Kingdom)
ObjectivesWe have developed an image-guided surgery system based on invisible near-infrared (NIR) fluorescent light. Presently, the only clinically-available NIR...Full Text Available
2009-07-01
UK PubMed Central (United Kingdom)
ObjectiveThe aim of this study was to evaluate the utility of volume-rendered helical computerized tomography (CT) angiography focusing tracheostomy tube and innominate artery for...Full Text Available
2011-02-01
UK PubMed Central (United Kingdom)
Background With the increasing use of cineless diagnostic angiography laboratories, modern telecommunication networks provide an excellent opportunity to transfer dynamic cardiac...Full Text Available
2001-12-01
Angina with a normal coronary angiogram caused by amyloidosis
UK PubMed Central (United Kingdom)
A case of severe intractable angina pectoris with normal angiography is presented. Following video assisted thoracic sympathectomy the patient died of heart failure. Microvascular cardiac amyloidosis...Full Text Available
2004-09-01
Single exposure energy subtraction chest radiography in the diagnosis of pulmonary cancer
Energy Technology Data Exchange (ETDEWEB)
A single exposure energy subtraction technique with a metal filter and an imaging plate for the Fuji Computed Radiography (FCR) system was developed for dual-energy subtraction radiography (DES) of the chest. By the use of this technique, 206 patients with suspected lung cancer were scanned in the clinical settings. The subtracted images in 200 patients, excluding six with poor image quality, were examined. Soft-tissue images (bone cancelled images) were useful in visualizing abnormality of the airway and nodules lying under the ribs; and bone images (soft-tissue cancelled images) in detecting rib metastases and the presence or absence of calcification in nodules. Additional information was acquired in 21 % (42/200). A single exposure is capable of neglecting motion artifacts. In addition, this technique may be of value in DES, which is considered to be one of the routine examinations, in view of low exposure doses. The ...
1987-03-01
Single exposure energy subtraction chest radiography in the diagnosis of pulmonary cancer
International Nuclear Information System (INIS)
A single exposure energy subtraction technique with a metal filter and an imaging plate for the Fuji Computed Radiography (FCR) system was developed for dual-energy subtraction radiography (DES) of the chest. By the use of this technique, 206 patients with suspected lung cancer were scanned in the clinical settings. The subtracted images in 200 patients, excluding six with poor image quality, were examined. Soft-tissue images (bone cancelled images) were useful in visualizing abnormality of the airway and nodules lying under the ribs; and bone images (soft-tissue cancelled images) in detecting rib metastases and the presence or absence of calcification in nodules. Additional information was acquired in 21 % (42/200). A single exposure is capable of neglecting motion artifacts. In addition, this technique may be of value in DES, which is considered to be one of the routine examinations, in view of low exposure doses. The ...
1987-01-01
UK PubMed Central (United Kingdom)
BackgroundThe construction of cDNA libraries is a useful tool to understand gene expression in organisms under different conditions, but random sequencing of unbiased cDNA collections...Full Text Available
International Nuclear Information System (INIS)
Sonography, subtraction scintigraphy, computed tomography and MRI were compared in 100 patients who had surgery 105 times for hyperparathyroidism (HPT). Surgical and pathological data were available for all operations. A total of 105 MR, 77 CT, 84 sonograms and 70 subtraction scintigrams were performed. The ability of the imaging modalities, individually and in combination, to detect HPT, histology, size, concomitant thyroid disease and location of the diseased glands has been evaluated. For primary HPT, sensitivity ranged from 68% for MRI to 40% for scintigraphy but was much lower for tertiary HPT with all modalities. The ability to identify diseased glands was strongly size dependent for all methods. If patients had had previous neck surgery, the most sensitive methods were MRI and scintigraphy and this also held true for patients with concomitant thyroid disease and ectopically located glands. The findings presented suggest that while ...
UK PubMed Central (United Kingdom)
Picocyanobacteria of the genus Synechococcus are important contributors to marine primary production and are ubiquitous in the world's oceans. This genus is genetically diverse, and...Full Text Available
2006-04-01
Local Structures and Interface Morphology of InGaAsN Thin Films Grown on GaAs
Energy Technology Data Exchange (ETDEWEB)
The compound semiconductor system InGaAsN exhibits many intriguing properties which are particularly useful for the development of innovative high efficiency thin film solar cells and long wavelength lasers. The bandgap in these semiconductors can be varied by controlling the content of N and In and the thin films can yet be lattice-matched to GaAs. In the present work, x-ray absorption fine structure (XAFS) and grazing incidence x-ray scattering (GIXS) techniques have been employed to probe the local environment surrounding both N and In atoms as well as the interface morphology of InGaAsN thin films epitaxially grown on GaAs. The soft x-ray XAFS results around nitrogen K-edge reveal that N is in the sp{sup 3} hybridized bonding configuration in InGaAsN and GaAsN, suggesting that N impurities most likely substitute for As sites in these two compounds. The results of In K-edge XAFS suggest a possible trend of a slightly larger coordination ...
1999-02-23
Energy Technology Data Exchange (ETDEWEB)
X-ray magnetic circular dichroism (XMCD) was used to probe the existence of induced magnetic moments in yttrium iron garnet (YIG) films in which yttrium is partly substituted with lanthanum, lutetium or bismuth. Spin polarization of the 4d states of yttrium and of the 5d states of lanthanum or lutetium was clearly demonstrated. Angular momentum resolved d-DOS of yttrium and lanthanun was shown to be split by the crystal field, the two resolved substructures having opposite magnetic polarization. The existence of a weak orbital moment involving the 6p states of bismuth was definitely established with the detection of a small XMCD signal at the Bi M{sub 1}-edge. Difference spectra also enhanced the visibility of subtle changes in the Fe K-edge XMCD spectra of YIG and {l_brace}Y, Bi{r_brace}IG films. Weak natural X-ray linear dichroism signatures were systematically observed with all iron garnet films and with a bulk YIG single crystal cut parallel to the (1 1 1) ...
2009-12-15
Non-selective cervical and cerebral three-dimensional rotational angiography
International Nuclear Information System (INIS)
To evaluate the usefulness of three-dimensional (3D) rotational angiography, cervical carotid or cerebral angiography was done without catheterizing the branches of the thoracic aorta. A 5-Fr pig-tail type catheter was passed into the ascending aorta via the radial artery or the femoral artery. Optimal carotid angiogram views were obtained using approximately 45 ml of contrast medium at a flow rate of 15 ml/sec. Optimal cerebral angiogram views were obtained using approximately 70 ml of contrast medium at a flow rate of 20 ml/sec. The contrast medium concentration was 300 to 350 mgI/ml. A satisfactory view could be obtained in 5 of 8 (63%) cases on cervical carotid 3D angiography and in 8 of 14 (57%) cases on cerebral 3D angiography. In all cases, no complications were noted. This method offers the advantages of requiring a relatively short procedure time and a decrease in radiation exposure. Further ...
2007-09-01
Compressed-shell integrity measurements in spherical implosion experiments
International Nuclear Information System (INIS)
The shell integrity near peak compression of spherical implosions using the 60-beam, 30-kJ UV OMEGA laser system [Opt. Commun. 133, 495 (1997)] has been measured. Hot core emission backlights a shell with a thin titanium-doped layer that is imaged at x-ray photon energies above and below the titanium K edge. The x-ray intensity ratio between the two images is related to perturbations in the cold, or absorbing, part of the shell. The measured cold-shell areal-density modulations, integrated over the time of peak compression, are of the order of 25% to 50% with nonuniformity spectra peaked at spatial wavelengths of 30 to 50 #mu#m and with the smallest detectable nonuniformity features extending down to spatial wavelengths of 12 to 15 #mu#m. Hot-shell areal-density modulations of the emitting part of the shell (inner edge) are of the order of 13% to 20%. The measured shell modulations are in agreement with the results of two-dimensional ...
2001-06-01
Anisotropy in Magnetic Properties and Electronic Structure of Single Crystal LiFePO4
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We report the experimental and theoretical results on the anisotropies in the magnetic properties and x-ray absorption spectra of single-crystal LiFePO4. A mean-field theory is developed to explain the observed strong anisotropies in Lande g-factor, paramagnetic Curie temperature, and effective moment for LiFePO4 single crystals. The values of the in-plane nearest- and next-nearest-neighbor spin exchange (J1 and J2), interplane spin exchange (J{perpendicular}), and single-ion anisotropy (D), obtained recently from neutron scattering measurements, are used for calculating the Curie temperatures with the formulas derived from the mean-field Hamiltonian. It is found that the calculated Curie temperatures match well with that obtained by fitting the magnetic susceptibility curves to the modified Curie-Weiss law. For the polarized Fe K-edge x-ray absorption spectra of single-crystal LiFePO4, a different feature assignment for the 1s4p transition features is proposed and ...
2008-01-01
Study of spatial resolution in three-dimensional rotational angiography
International Nuclear Information System (INIS)
In interventional radiology (IVR) of cerebral aneurysms, it is important to understand the form and physical relationships between the cerebral aneurysm and the surrounding vessels. However, because the vessels in the head area are highly complex, it can be difficult to comprehend the structure using conventional angiography. Therefore, three-dimensional rotational angiography (3D-RA) has been used in recent years. This article discusses studies of the spatial resolution of 3D-RA. We reconstructed 3D-RA of an acrylic slit phantom (slit widths: 0.5, 0.75, 1.0, 1.5 mm) and examined spatial resolution by visual evaluation and profile curves. When the slit phantom was arranged to avoid the effect of beam hardening, the spatial resolution of 3D-RA was found to be as high as 0.75 mm. When the slit phantom was placed orthogonal to the rotational axis of the C-arm, the spatial resolution of 3D-RA was decreased because of the cone angle effect of ...
2006-03-01
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We report a patient who developed occlusion of the intracranial major arteries induced by radiation therapy for craniopharyngioma. The patient, a 9-year-old boy, presented with deterioration of vision, nausea and vomiting. He underwent a right ventriculo-peritoneal shunt operation, and the tumor was partially removed. Postoperatively, he received focal radiation therapy with total of 60 Gy. Preoperative cerebral angiography, cerebral vessels had no sigh of occlusive lesion or stenosis. One year after irradiation, he started to have repeated cerebral ischemic attacks. But no regrowth of the tumor was detected on CT scans. Two years and 8 months after irradiation, he suddenly had right hemiparesis. Cerebral angiography revealed severe stenosis of the right anterior cerebral artery (precommunicating segment), middle cerebral artery (horizontal portion) and terminal portion of the right carotid artery. Left carotid angiography ...
1994-10-01
International Nuclear Information System (INIS)
We report a patient who developed occlusion of the intracranial major arteries induced by radiation therapy for craniopharyngioma. The patient, a 9-year-old boy, presented with deterioration of vision, nausea and vomiting. He underwent a right ventriculo-peritoneal shunt operation, and the tumor was partially removed. Postoperatively, he received focal radiation therapy with total of 60 Gy. Preoperative cerebral angiography, cerebral vessels had no sigh of occlusive lesion or stenosis. One year after irradiation, he started to have repeated cerebral ischemic attacks. But no regrowth of the tumor was detected on CT scans. Two years and 8 months after irradiation, he suddenly had right hemiparesis. Cerebral angiography revealed severe stenosis of the right anterior cerebral artery (precommunicating segment), middle cerebral artery (horizontal portion) and terminal portion of the right carotid artery. Left carotid angiography ...
1994-01-01
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Purpose: An animal model is used to investigate whether MR angiography combined with super-paramagnetic particles of iron oxide (SPIO) is suitable for detecting thromboses. Methods: 42 rats in groups of 7 each were examined on days 1, 3, 5, 7, 9 and 11, respectively, after mechanical/chemical thrombus induction in a 1.5 Tesla magnet with a FISP sequence (TR/TE/FA 50 ms/6 ms/40 ). Imaging was performed before and up to 90 minutes after intravenous injection of 30 {mu}mol FE/kg BW of the experimental SPIO (hydrodynamic diameter, 34{+-}17 nm LLS; R1 and R2 relaxivity at 0.47 T, 31 and 57 L/(mmol*s)). MIP reconstructions of MR angiographies were submitted to consensus assessment by two examiners using histology as the gold standard. Results: The image quality of MIP reconstructions was rated as good in 38 of 42 cases. With regard to thrombotic vessel occlusion, MR angiography coincided with histology in 17 of 42 cases and ...
1999-03-01
International Nuclear Information System (INIS)
Comparative analysis of diagnostic accuracy (dignity determination) in CT-guided fine-needle biopsy (141 patients), CT (141), ultrasonography (89), angiography (50), and cholegraphy (ERCP, 55), was carried out in suspected space-occupying lesions of the pancreas. With accuracy of 86%, sensitivity of 37% and specificity of 92% fine-needle biopsy was superior to imaging procedures. Additional comparison of the results concerning the patients and Roc curves confirm the statements. For reduction of the number of imaging investigations a diagnostic algorithm is proposed, that starts with diagnostic CT and subsequent fine-needle biopsy controlled by CT. This would result in a more adequate use of angiography and ERCP and in the elimination of ultrasonography. (author).
British Library Electronic Table of Contents (United Kingdom)
Purpose We evaluated low-contrast injection protocols for coronary computed tomography angiography (CTA) using a 64-detector scanner and the test bolus technique. Materials and methods We randomly assigned 60 patients undergoing coronary CTA to one of two contrast material (CM) injection protocols. For the lowcontrast dose protocol (Plow), the patients received injections of iohexol-350 [0.7 ml/kg body weight (BW)] during 9 s, and the test-bolus technique was used. Under the conventional protocol (Pconv), they received iohexol-350 (1.0 ml/kg BW) during 15 s, and bolus tracking was used. We compared the protocols for attenuation values in the ascending aorta and coronary arteries and for the amount of CM required. Results There was no significant difference in the mean CT attenuation of the...
2011-01-01
British Library Electronic Table of Contents (United Kingdom)
Coronary angiography has provided an unrivalled appreciation of coronary anatomy fostering a far greater appreciation of the extent of atherosclerotic disease. However, the subjectivity of coronary angiography at determining the extent of plaque has been exposed with IVUS. Indices of coronary physiology have provided valuable adjunctive information as to the physiological importance of specific lesions. Fractional flow reserve is an established method for evaluating the significance of epicardial stenoses. Fractional flow reserve guided percutaneous coronary intervention is associated with improved outcomes when compared to a conventional angiographic guided strategy, particularly in intermediate lesions. The use of coronary physiology in the cath lab represents a new avenue to guide appro...
2011-01-01
[75Se]Selenomethionine scanning for parathyroid localization should be abandoned
International Nuclear Information System (INIS)
Image subtraction techniques, in conjunction with [75Se]selenomethionine (75Se) scintigraphy, have recently been suggested to be a potentially valuable tool for localization of parathyroid abnormalities. With use of these techniques, we prospectively studied 15 patients scheduled for parathyroid operations. Postoperatively, all were normocalcemic. Anterior scintiscans of the neck were divided into quadrants, and regions of enhanced uptake were assigned to one or more quadrants. On this basis, by chance alone a minimum of 25% of single-gland enlargements would be assigned to the correct quadrant of the neck. We found that by use of 75Se scanning only 8 of 22 abnormal glands (36%) were assigned to the quadrant of the neck in which they were found intraoperatively. In no case was a clearly visualized focus of parathyroid activity encountered. These results do not justify the continued use of 75Se scintigraphy with or without image subtraction in ...
Groundtruth approach to accurate quantitation of fluorescence microarrays
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To more accurately measure fluorescent signals from microarrays, we calibrated our acquisition and analysis systems by using groundtruth samples comprised of known quantities of red and green gene-specific DNA probes hybridized to cDNA targets. We imaged the slides with a full-field, white light CCD imager and analyzed them with our custom analysis software. Here we compare, for multiple genes, results obtained with and without preprocessing (alignment, color crosstalk compensation, dark field subtraction, and integration time). We also evaluate the accuracy of various image processing and analysis techniques (background subtraction, segmentation, quantitation and normalization). This methodology calibrates and validates our system for accurate quantitative measurement of microarrays. Specifically, we show that preprocessing the images produces results significantly closer to the known ground-truth for these samples.
2000-12-01
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The objective of this study was to compare contrast-enhanced magnetic resonance angiography (CE MRA) and multislice computed tomographic angiography (MS CTA) in the follow-up of thoracic stent-graft placement. The CE MRA and MS CTA were performed following nitinol stent-graft treatment due to thoracic aneurysm (n=4), intramural bleeding (n=2) and type-B aortic dissection (n=5). Corresponding evaluation of arterial-phase imaging characteristics focused on the stent-graft morphology and leakage assessment. Stent-graft and aneurysm extensions were comparable between both techniques. Complete exclusion (aneurysm, n=4; dissection, n=2) was assessed with high confidence with CE MRA and MS CTA. Incomplete exclusion (intramural bleeding, n=2; dissection, n=3) was assigned to lower confidence scores on CE MRA compared with MS CTA. On CE MRA the stent-graft lumen demonstrated an inhomogeneous signal, the stent struts could not be assessed. The CE MRA can ...
2003-07-01
Medical explorations by radioisotopes in Lebanon
International Nuclear Information System (INIS)
This study mainly concerns medical explorations by radioisotopes. Detectors with medical exams and applications are described. Ionisation chambers, semiconductor detectors and scintillation counters are also presented. Uses of radioisotopes in medicine in vivo and in vitro techniques are explained. Examples of scintiscanning are given like: angiography, nuclear cardiography and thyroid scintiscanning. The importance of the study is to present a panorama of nuclear medicine laboratories -at the time- in hospitals in Lebanon.
Hepatocellular carcinoma: recent advances in diagnosis with iodized oil
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This opinion presents an overview of recent developments in the diagnosis and treatment of hepatocellular carcinoma (HCC) in Japan. The use of Ethiodol (iodized ethyl ester of the fatty acid of poppyseed oil) for hepatic angiography in diagnosing and treating (combined with chemotherapeutic agents) HCC has been reported. Ethiodol has been found to localize in HCC and remain there for long periods. The implications of these findings are discussed.
1985-01-01
Energy Technology Data Exchange (ETDEWEB)
In embodiments, spectroscopic monitor monitors modulated light signals to detect low levels of contaminants and other compounds in the presence of background interference. The monitor uses a spectrometer that includes a transmissive modulator capable of causing different frequency ranges to move onto and off of the detector. The different ranges can include those with the desired signal and those selected to subtract background contributions from those with the desired signal. Embodiments of the system are particularly useful for monitoring metal concentrations in combustion effluent.
2003-01-01
International Nuclear Information System (INIS)
Eight patients with primary hyperparathyroidism were examined preoperative to locate the affected parathyroid glands. The localisation was done with technetium 99m and thallium 201. This new method seems to be of great value to locate preoperative the affected parathyroid glands. (R.B.).
Energy Technology Data Exchange (ETDEWEB)
Bone images obtained by single exposure dual energy subtraction with computed radiography, a new image processing method, were evaluated for the detectability of calcification in lung nodules in both phantom and clinical studies. In the phantom study, five simulated nodules containing known and uniformly distributed amounts of calcium hydroxide were placed in a human chest phantom and images were obtained the following five techniques: (1) conventional radiography (CXR), (2) low kV conventional radiography (Low), (3) Fuji computed radiography (FCR), (4) bone images with conventional singles exposure energy subtraction (ES) and (5) bone image with fine single exposure energy subtraction (FES). The detectability of calcification in the simulated nodules was evaluated by six radiologists using ROC analysis and two-way analysis of variance. In the clinical study, images of 42 lung nodules (21 calcified lung nodules and 21 ...
1995-08-01
International Nuclear Information System (INIS)
Bone images obtained by single exposure dual energy subtraction with computed radiography, a new image processing method, were evaluated for the detectability of calcification in lung nodules in both phantom and clinical studies. In the phantom study, five simulated nodules containing known and uniformly distributed amounts of calcium hydroxide were placed in a human chest phantom and images were obtained the following five techniques: 1) conventional radiography (CXR), 2) low kV conventional radiography (Low), 3) Fuji computed radiography (FCR), 4) bone images with conventional singles exposure energy subtraction (ES) and 5) bone image with fine single exposure energy subtraction (FES). The detectability of calcification in the simulated nodules was evaluated by six radiologists using ROC analysis and two-way analysis of variance. In the clinical study, images of 42 lung nodules (21 calcified lung nodules and 21 ...
1995-01-01
International Nuclear Information System (INIS)
Objective: To investigate transcutaneous oximetry as parameter of the microcirculation is correlated to ankle-brachial-index as parameter of the macrocirculation after peripheral angioplasty procedures. Design: Prospective study. Materials and methods: 60 patients suffering from intermittent claudication were scheduled for angioplasty treatment. 45 patients were considered as eligible for angioplasty after angiographic evaluation, 15 patients underwent angiography only. Transcutaneous oximetry measurements were performed before the procedure, at the end of intervention, 24 h as well as 2 and 4 weeks after percutaneous transluminal angioplasty. Ankle-brachial-indices were obtained before intervention, 24 h as well as 2 and 4 weeks later. Results: Ankle-brachial-indices increased significantly at 24 h after angioplasty in patients being treated with angioplasty. Transcutaneous oximetry values dropped significantly at the end of the procedure and returned close to the ...
2007-11-01
MRI with pathogenic correlation of small renal cell carcinoma
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MRI, ultrasonography and angiography were performed on 24 cases with small renal cell carcinoma, and data were compared with pathological architecture type. An average diameter of cancer was 20.8 mm (10-30 mm). Each tumor was pathologically classified into four architecture types: alveolar type (15 cases), papillary type (5 cases), tubular type (3 cases) and cystic type (1 case). In comparison with renal cortex alveolar type renal cell carcinoma showed equal or low signal in T1-weighted images and equal or high signal in T2-weighted images. Papillary and tubular types showed high signal in T1-weighted images, and low signal in T2-weighted images. In alveolar type, many cases showed equal echo in ultrasonography and hypervascularity in angiography, and in papillary and tubular types, many cases showed high echo and hypovascularity. There were many cases with papillary type small cell carcinoma which showed low signal intensity of T2-weighted ...
1999-11-01
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Ten patients with suspected islet cell tumors (seven with possible gastrinomas, three with insulinomas) underwent diagnostic evaluation with dynamic CT scanning, routine CT scanning, angiography, and sonography. Venous sampling was also performed in selected instances. Nine sites of gastrinoma and three insulinomas were confirmed surgically in eight patients. Two patients had negative surgical explorations. Routine CT demonstrated five of the nine gastrinomas and one of two insulinomas. Angiography was positive in six of nine gastrinomas and all three insulinomas. Sonography showed only two of the nine gastrinomas and two of the three insulinomas. Dynamic CT scanning demonstrated three additional lesions (two gastrinomas, on insulinoma) not visible on routine CT scanning. Although most of these lesions were visible arteriographically, dynamic CT scans at the appropriate level localized the pathology in the transverse plane and greatly aided in ...
1984-09-01
Experience with abdominal gamma imaging in patients with bleeding of the lower digestive tube
International Nuclear Information System (INIS)
This study concerns our experiences with abdominal gamma imaging using Tc-99m colloid and with abdominal angiography using Tc-99m-pyrophosphate labelled erythrocytes ''in vivo'' based on the modified technique described by Callahan. The dynamic or perfusion phase was first performed, then the static phase during which for the first two hours scans were taken every 15 minutes and thereafter every 4-6 hours. The routine image corresponds to the first, although it was necessary at times to take oblique projections. The study was felt to be accomplished after 48 hours upon observing no extravasation of radioactive material in the abdominal region, or upon detecting a bleeding site. The investigation was performed on 11 patients, 8 having positive scans of abdominal extravasation, later confirmed in 6 by endoscopy and by surgery. In 2, the presence of salmonelosis was shown by laboratory analysis. Endoscopy and angiography XR are both invasor ...
1985-04-25
Diagnostic features of intrahepatic cholangiocarcinoma according to the gross type classification
International Nuclear Information System (INIS)
Forty resected cases of intrahepatic cholangiocarcinoma were classified into four types according to the gross appearance; type I: mass forming type (n=8), type II: mass forming with periductal infiltrating type (n=20), type III: periductal infiltrating type (n=9) and type IV: intraductal growth type (n=3). Diagnostic features of these four types were studied. Peripheral enhancement was a common angiographic feature and tumor stains were recognized in 88%, 20%, 0%, 33%, respectively. Angiography and dynamic computed tomography (D-CT) were useful in differential diagnosis with hepatocellular carcinoma. Accuracy rate in diagnosis of portal vein involvement by angiography and D-CT was 82% and 91%, respectively. MRI was more useful in tumor detection than D-CT in cases with attenuation difference, in 55% of type II and in 75% of type III. Increase of arterial involvement, biliary tract involvement and portal vein involvement, incidence of lymph ...
1998-08-01
Computed tomography (CT) in renal trauma
International Nuclear Information System (INIS)
CT scans were performed on 25 patients suspected of sustaining ranal trauma. The utility of CT in both detecting renal damage and appraising the gravity of injuries was assessed. Nowadays, in fact, nephrectomy or reserved for lesions devastanting the kidney parenchyma or rupturing the renal pedicle; so it is very important to identyfy both the purposes of a better planned therapeutic approach. CT does both, being more accurate than urography in the detection of renal fractures, intra or extraparenchymal hematomas and contrast media extravasation. Urography very often shows aspecific lesion patterns and sometimes it is also falsely negative. In the present series CT was more reliable than angiography itself, particulary in the diagnosis of extra-renal hematic collections, contrast media extravasation and injuries to the other abdominal organs. Although CT may arouse the suspicion of and sometimes correctly diagnose vascular lesions, such as renal infarction, ...
1987-01-01
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Purpose: To describe the clinical aspects and evaluate optical coherence tomography of macular microholes. Methods: Seven patients were assessed (8 eyes) with microholes of the macula. All patients underwent complete eye examination, fundus photography, fluorescent angiography and OCT-3 imaging. Results: Ages ranged from 26 to 69 years. Six patients were female (85.7%) and five of them had microhole in the right eye. The presenting symptom was decrease in visual acuity (71.3%) and central scotoma in (14.3%). Five eyes (71.4%) had no defects shown by fluorescent angiography. A defect in the outer retina was demonstrated in all eyes on optical coherence tomography. The lesions were nonprogressive. Conclusion: Macular microholes are small lamellar defects in the outer retina. The condition is nonprogressive, generally unilateral and compatible with good visual acuity. Fundus biomicroscopy associated with an optical coherence tomography are the ...
2009-07-01
International Nuclear Information System (INIS)
The aim of this study was to assess the body weight-tailored contrast material injection protocol for 64-detector computed tomography (CT) to maintain optimal coronary CT attenuation. A total of 60 patients who underwent CT coronary angiography were assigned to one of three groups: protocol A, total of 0.7 ml kg"-"1 with 300 mg I/ml iodine concentration; protocol B, total of 0.6 ml kg"-"1 with 350 mg I/ml; protocol C, total of 0.7 ml kg"-"1 with 350 mg I/ml. The injection duration was 10 s in all patients. The proportion of intracoronary attenuation values >325 Hounsfield unit (HU) was compared on a per-vessel and per-patient basis. The attenuation value was significantly more likely to exceed 325 HU with protocol C (95% for reader 1 and 90% for reader 2) than with protocol A or B on the per-vessel analysis (P325 HU) with 64-detector CT when using an injection duration of 10 s. (author)
2011-01-01
International Nuclear Information System (INIS)
Twenty-two patients, all with surgically proven primary hyperparathyroidism, were studied by TI-201 thallous chloride and Tc-99m pertechnetate subtraction imaging. Fifteen parathyroid adenomata and one hyperplastic gland between 0.33 and 14.8 g were correctly localized in 16 patients. Two adenomata and seven hyperplastic or histologically normal parathyroids between 0.1 g and 1.4 g in seven patients were not localized. One patient had a correctly localized 13.0-g adenoma with a nonlocalized 0.3 g hyperplastic parathyroid gland and there were two false positive localizations. Sensitivity was 64% (glands), and 73% (patients). There was only fair correlation with parathormone (PTH) levels, but these were elevated in all but four of the patients with correctly localized parathyroids. The authors conclude that the imaging procedure is useful but its sensitivity is limited by difficulty in localizing correctly small glands, particularly those of less than 0.5 g, which ...
HST/ACS observations of shell galaxies: inner shells, shell colours and dust
AIM:Learn more about the origin of shells and dust in early type galaxies. METHOD: V-I colours of shells and underlying galaxies are derived, using HST Advanced Camera for Surveys (ACS) data. A galaxy model is made locally in wedges and subtracted to determine shell profiles and colours. We applied Voronoi binning to our data to get smoothed colour maps of the galaxies. Comparison with N-body simulations from the literature gives more insight to the origin of the shell features. Shell positions and dust characteristics are inferred from model galaxy subtracted images. RESULT: The ACS images reveal shells well within the effective radius in some galaxies (at 1.7 kpc in the case of NGC 5982). In some cases, strong nuclear dust patches prevent detection of inner shells. Most shells have colours which are similar to the underlying galaxy. Some inner shells are redder than the galaxy. All six shell galaxies show out of dynamical equilibrium dust ...
2007-01-01
International Nuclear Information System (INIS)
Objective: To compare the efficiency of dual energy subtraction and conventional direct digital radiography in signal detecting ability. Methods: 200 plastic balls which were 4 mm in diameter were taken as signals and were placed on a 10 cm thick plastic board and the right upper thorax of a healthy volunteer. The signals were examined by DES and CDR separately and were estimated by 3 radiologists with 5-value-differentiation method. ROC curve analysis was made by ROC kit software. Results: when signals on plastic board were detected by CDR and DES, ROC curve analysis indicated that there was no significant difference (P=0.4851 > 0.05, two-tailed) between the area under the ROC curves of the two methods (Az=0.9931 for CDR and Az=0.9879 for DES). The difference was significant (P=0.0002 <0.01, two-tailed) between the area under the ROC curves of CDR and DES (Az=0.7276 for CDR and Az=0.8561 for DES), when the signals on the right upper thorax of a volunteer ...
2005-06-01
Energy Technology Data Exchange (ETDEWEB)
Manganese model complexes, relevant to the oxygen-evolving complex (OEC) in photosynthesis, were studied with Mn K-edge X-ray absorption near-edge spectroscopy (XANES), Mn Kb X-ray emission spectroscopy (XES), and vibrational spectroscopy. A more detailed understanding was obtained of the influence of nuclearity, overall structure, oxidation state, and ligand environment of the Mn atoms on the spectra from these methods. This refined understanding is necessary for improving the interpretation of spectra of the OEC. Mn XANES and Kb XES were used to study a di-(mu)-oxo and a mono-(mu)-oxo di-nuclear Mn compound in the (III,III), (III,IV), and (IV,IV) oxidation states. XANES spectra show energy shifts of 0.8 - 2.2 eV for 1-electron oxidation-state changes and 0.4 - 1.8 eV for ligand-environment changes. The shifts observed for Mn XES spectra were approximately 0.21 eV for oxidation state-changes and only approximately 0.04 eV for ligand-environment changes. This ...
2001-05-16
X-ray absorption spectroscopy of bacterial sulfur globules
Energy Technology Data Exchange (ETDEWEB)
Sulfur K-edge X-ray absorption spectroscopy is a powerful in situ probe of sulfur biochemistry in intact cells and tissues. Under favorable circumstances the technique can provide quantitative information on the chemical identify of the sulfur species that are present in a sample. Prange et al. have recently reported an X-ray absorption spectroscopic study of bacterial sulfur storage globules. Unfortunately there are substantial problems with the experimental technique employed that, they contend, lead to completely erroneous conclusions. In the more recent of their two papers Prange et al. employed a curve-fitting method similar to that used by us (for more than 10 years). In essence, the method employs simply fitting a linear combination of the spectra of standard compounds to that of the unknown, in this case cultures of bacterial cells. This type of analysis can provide quantitative estimates of the individual sulfur types in the sample, but is critically ...
2002-08-01
International Nuclear Information System (INIS)
A new iron phosphate (NH4)4Fe3(OH)2F2[H3(PO4)4] has been synthesized hydrothermally at HF concentrations from 0.5 to 1.2 mL. Single-crystal X-ray diffraction analysis reveals its three-dimensional open-framework structure (monoclinic, space group P21/n (No. 14), a=6.2614(13) A, b=9.844(2) A, c=14.271(3) A, ?=92.11(1)o, V=879.0(3) A3). This structure is built from isolated linear trimers of corner-sharing Fe(III) octahedra, which are linked by (PO4) groups to form ten-membered-ring channels along [1 0 0]. This isolated, linear trimer of corner-sharing Fe(III) octahedra, [(FeO4)3(OH)2F2], is new and adds to the diverse linkages of Fe polyhedra as secondary building units in iron phosphates. The trivalent iron at octahedral sites for the title compound has been confirmed by synchrotron Fe K-edge XANES spectra and magnetic measurements. Magnetic measurements also show that this compound exhibit a strong antiferromagnetic exchange below TN=17 K, consistent with ...
2010-12-01
New materials synthesis: characterization of some metal-doped antimony oxides
Energy Technology Data Exchange (ETDEWEB)
In order to understand the chemistry of altermetal dopants in antimony oxide, the detailed structural characterization of two ..beta..-Sb/sub 2/O/sub 4/ compounds is reported, Mo-doped ..beta..-Sb/sub 2/O/sub 4/ (1.5 metal%) and V-doped ..beta..-Sb/sub 2/O/sub 4/ (5 metal%). The methods used to characterize these materials are X-ray and neutron diffraction, scanning electron microscopy, Mo K-edge extended X-ray absorption fine structure spectroscopy, and elemental analysis. The atomic position of each of these dopants in Sb/sub 2/O/sub 4/ is radically different as is the overall effect on the host structure. Molybdenum does not substitute for Sb atoms, rather the Mo atoms are found in channels of electron density formed by Sb/sup 3 +/ lone pairs. The two nearest Sb/sup 3 +/ are absent and the oxygen stoichiometry is preserved. The formula is Sb/sub 1.97/Mo/sub 0.015/O/sub 4/. Vanadium incorporates substitutionally for the Sb/sup 3 +/ atoms and there are random ...
1986-10-01
An EXAFS investigation of the structures of bromocopper(II) complexes in some solutions
International Nuclear Information System (INIS)
The structures of bromocopper(II) complexes in methanolic (M1, M2, M3, M4), ethanolic (E), and aqueous (H) solutions were determined by the analyses of the Cu K- and Br K-edge EXAFS spectra using a curve-fitting method. The molar concentrations of Cu and Br in these solutions prepared by CuBr_2 and LiBr are 0.996 and 1.992 (M1), 1.015 and 5.381 (M2), 0.493 and 4.525 (M3), 0.260 and 4.073 (M4), 1.031 and 4.313 (E), and 0.982 and 5.426 (H). In M1 solution the interatomic distances for the Cu-O_e_q, Br_e_q-Cu, and Br_e_q-O_e_q (_e_q = equatorial) were 2.00A, 2.35A, and 3.15A respectively, and the Br_e_q-Cu-O_e_q angle was estimated as about 92 deg. Therefore, trans-dibromo bis(methanol)copper(II) complex with a slightly distorted planar structure was proposed to be dominant complex species in M1 solution. The interatomic distances in M2, M3, M4 and E solutions were 2.37A and 3.45A (average) for the Br_e_q-Cu and Br_e_q-Br_e_q respectively. The Br_e_q-Cu-Br_e_q angle, ...
Radiodiagnosis of Ewing's sarcoma of the rib in children
International Nuclear Information System (INIS)
The results of the examination of 23 children with Ewing's sarcoma of the rib were analyzed: panoramic chest X-rays in 4 projections, spot radiographs of the robs, superexposed pictures, laterograms, urography, angiography, computerized tomography, and scanning of the skeleton. Causes of diagnostic errors made at the first consultation by a physician, were identified. Peculiarities of X-ray signs of tumors of this site in children were studied. Diagnostic difficulties in tumors complicated by pleurisy and in tumors of small sizes with extrapleural growth were shown. Inclusions in the extraoseous tumor component were noted in 8.7% of the cases.
Radiation exposure of patients and operators during interventional radiology
International Nuclear Information System (INIS)
Surface doses received by patients and operators were measured during 30 interventional radiological procedures (ten percutaneous transhepatic biliary drainages, ten percutaneous nephrostomies, ten percutaneous transluminal angioplasties). In addition, organ doses to the patient were determined using an Alderson-Rando phantom. These served as a basis for calculating the so-called somatic dose indices. It was found that the somatic radiation risk to the patient is relatively small despite prolonged periods of fluoroscopy. However, exposure of the hands and lenses of the operator could easily reach the limits thought acceptable while carrying out these procedures with additional angiography. (orig).
1986-01-01
Three-dimensional data processing for time resolved gamma-ray spectrometry
International Nuclear Information System (INIS)
A new acquisition and evaluation procedure has been introduced for the measurement of time-dependent processes in gamma-ray spectrometry, in order to extract more information, including half-lives, from the data recorded during acquisition and to enable a more comprehensive analysis of the results. These advanced, off-line data evaluation techniques improve the selectivity and the background subtraction and make it possible to estimate the important analytical parameters (e.g., half-lives) more accurately than with the usual decay curve fitting method. (author)
Moessbauer diffraction measurements on polycrystalline bcc iron
Energy Technology Data Exchange (ETDEWEB)
In the early days of Moessbauer spectroscopy, it was demonstrated that coherent scattering of photons emitted by a Moessbauer source can be observed. In spite of the fact that scattering experiments could give information not accessible by the absorption method, they are not widely used. The reasons for this are, on the one hand, experimental difficulties, and on the other hand, the form of the samples, which should be large single crystals in most cases. In this work, we present a Moessbauer diffraction measurement on polycrystalline bcc iron where these problems have been overcome. We demonstrate that using the kinematical theory of gamma-ray diffraction, useful information on the relative orientation of the crystallographic axis to the hyperfine field directions can be subtracted. (orig.)
1994-11-01
Energy Technology Data Exchange (ETDEWEB)
We discuss the inclusive production of D{sup *{+-}} mesons in {gamma}p collisions at DESY HERA, based on a calculation at next-to-leading order in the general-mass variable-flavor-number scheme. In this approach, MS subtraction is applied in such a way that large logarithmic corrections are resummed in universal parton distribution and fragmentation functions and finite mass terms are taken into account. We present detailed numerical results for a comparison with data obtained at HERA and discuss various sources of theoretical uncertainties. (orig.)
2009-02-15
Energy Technology Data Exchange (ETDEWEB)
In dual-energy projection radiography with double exposures, rapid energy switching is mandatory to eliminate motion artifacts, but it is costly for use in a clinical environment. We developed a system with practical exposure intervals at reasonable cost by modifying a condenser-type X-ray generator. A commercially available system for digital radiography (Fuji Computed Radiography, FCR) was used to subtract images. This report dealt with technical factors to obtain adequate kV and mAs settings in this technique.
1987-04-01
Dual-energy projection radiography using condenser discharge x-ray generator and FCR
International Nuclear Information System (INIS)
In dual-energy projection radiography with double exposures, rapid energy switching is mandatory to eliminate motion artifacts, but it is costly for use in a clinical environment. We developed a system with practical exposure intervals at reasonable cost by modifying a condenser-type X-ray generator. A commercially available system for digital radiography (Fuji Computed Radiography, FCR) was used to subtract images. This report dealt with technical factors to obtain adequate kV and mAs settings in this technique. (author).
1987-01-01
Convection heat loss from a cavity receiver
Energy Technology Data Exchange (ETDEWEB)
The receiver whose convective heat loss test results are presented was designed to absorb 5 MW of solar energy, using a molten salt working fluid. During the tests, this receiver was brought to a temperature of about 343 C by a small group of heliostats. Total receiver heat loss due to emitted radiation, conduction and convection was first determined, and the convection loss was established by calculating the radiation and conduction losses analytically and subtracting their sum from the total. Losses due to convection are found to be 1.43 percent of the total heat input.
1984-02-01
Atomic photoelectric effect near threshold edges
Energy Technology Data Exchange (ETDEWEB)
Total photon attenuation coefficients near absorption edges are determined in certain suitable elements and compounds. Photoelectric cross sections for elements are deduced from these by subtracting the coherent and incoherent scattering cross sections as well as other elemental cross sections in the cases of compounds. Certain deviations are observed on comparison with the available theoretical and experimental compilations. The I/sub L//sub ..cap alpha..//Il x-ray intensity ratio measured by photon excitation near threshold is found to agree better with the theory than the other available experimental data.
1985-07-01
Atomic photoelectric effect near threshold edges
International Nuclear Information System (INIS)
Total photon attenuation coefficients near absorption edges are determined in certain suitable elements and compounds. Photoelectric cross sections for elements are deduced from these by subtracting the coherent and incoherent scattering cross sections as well as other elemental cross sections in the cases of compounds. Certain deviations are observed on comparison with the available theoretical and experimental compilations. The I/sub L//sub #alpha#//Il x-ray intensity ratio measured by photon excitation near threshold is found to agree better with the theory than the other available experimental data.
1985-01-01
International Nuclear Information System (INIS)
Coronary angiography provides anatomical information whereas thellium myocardial scintigraphy measures resistive tissue perfusion. Because of this fundamental difference. The authors question the validity of using coronary angiography as the gold standard to judge thellium myocardial scintigraphy. The authors studied 20 patients undergoing elective percutaneous coronary angioplasty who fulfilled the following criteria: (1) history of chest pain; (2) angiographically significant single vessel disease (>50% stenosis); (3) no prior myocardial infarction. All patients underwent maximal exercise thallium single photon emission computed tomography (T1-SPECT). Tl-SPECT was scored visually according to a 0 to 3 scale (0=absent uptake; 1=markedly decreased uptake; 2=minimally decreased uptake; 3=normal uptake). Translesional gradient and percent stenosis were measured before and after angioplasty. The authors found that significant linear ...
1985-06-02
The value of cardiac catheterization and cineangiography in infantile lobar emphysema
International Nuclear Information System (INIS)
Lobar emphysema is an uncommon cause of respiratory distress in infancy. Congenital heart disease is seen in about 20% of the patients with infantile (congenital) lobar emphysema. We described six infants with lobar emphysema. In three of them a congenital heart disease was demonstrated by cardiac catheterization and cineangiography; two had a tetralogy of Fallot with right aortic arch and the third infant a ventricular septal defect. The pulmonary angiography showed stretching of the arteries with very poor filling of the peripheral arteries and a characteristic smaller pulmonary vein in the affected lobe. In all the six patients the pulmonary artery pressure was normal. All the patients underwent lobectomy with good results. We feel that a preoperative cardiac catheterization and cineangiography is of value in this very sick group of infants. (orig.).
Targeted drug delivery under MRI guidance
British Library Electronic Table of Contents (United Kingdom)
The main goal of local drug delivery is to increase the concentration of a specific therapeutic agent in a target tissue with minimal nontarget distribution. Compared to systemic therapy, local drug delivery provides a high level of therapeutic efficacy with minimal systemic effects. The current primary imaging modality for drug delivery has been x-ray angiography, but it has major limitations including anatomical ambiguity and inability to visualize the targeted tissues. Due to these inherent problems, MR guidance has been explored as an alternative imaging modality for guiding and monitoring of drug therapy. Recently, interventional MR (XMR) systems have been implemented that have both dual x-ray and MRI capabilities in a single suite and allow for real-time interventional procedures to ...
2008-01-01
Prenatal diagnosis and perinatal management of left coronary artery to right atrium fistula.
Serious complications due to coronary artery fistulae have been described. Most authors recommend early intervention at the time of diagnosis. We present a case of a fistula originating from a dilated left coronary artery and draining into the right atrium, which was diagnosed prenatally by color Doppler echocardiography. During pregnancy, the echocardiographic findings remained unchanged, and there were no signs of heart failure. After birth, the fistula was confirmed by angiography. Additionally, a persistent left superior vena cava draining into the coronary sinus and a very small ventricular septal defect were detected. The fistula was closed successfully by transcatheter coil embolization. At 17 months old the child was in good clinical condition. Prenatal diagnosis of coronary artery fistulae may be possible and may improve perinatal management and outcome. PMID:12047543
2002-06-01
International Nuclear Information System (INIS)
Iopentol (350 mg I/ml) has been compared with iohixol (350 mg I/ml) in a double-blind randomized parallel group trial with 32 and 35 patients receiving iopentol and iohexol, respectively. Coronary angiography and left ventriculography were performed, and the mean total volume injected was 124 ml of iopentol and 135 ml of iohexol . There were no statistically significant differences regarding changes in heart rate and frequency of adverse advents, which were the primary parameters, between the two groups of patients. Blood pressure and ECG parameters revealed only minor fluctuations which were of no clinical relevance. The visualization of the coronary arteries and the left ventricle were the same with both contrast media, as was the diagnostic quality. The results support the use of iopentol in cardioangiography. (author). 1 ref.; 5 tabs.
International Nuclear Information System (INIS)
Rotatostereoradiographic (RSRG) images are displayed in an oscillating, rotational manner. While reviewing these rotating images, the radiologist may become psychologically irritated by the rotation. A rapidly rotating display of linear subjects gives one three-dimensional depth information. This three-dimensional sense is lost if the rotation speed is too slow. The authors of this paper determined the slowest possible rotating display speed that allows perception of three-dimensional depth information minimizing psychological irritation. In the RSRG device (Shimadzu ROTATO-360), an x-ray tube coupled with an image intensifier rotates through a 180 degrees arc in 1.8 or 2.25 seconds. Both rotation times could be doubled. The images were displayed at four different speeds, covering the 180 degrees arc in 1.8, 2.25, 3.6, and 4.5 seconds.
1990-11-25
CF findings of bowel infarction in 56 surgical patients, 5 of whom with reversible ischemia
International Nuclear Information System (INIS)
Bowel infarction is a rare and typical condition of the elderly; despite improvements in diagnostic imaging and vascular surgery, bowel infarction remains a major cause of acute abdomen, with mortality rates ranging 70-80%. Diagnosis on often late because clinical sings, laboratory data and radiologic findings are a specific. The authors investigated radiographic and particular CT patterns of intestinal infraction in 56 patients submitted to surgery within 12 hours of admission. We also report the CT findings of 5 of these patients who had reversible mesenteric ischemia. CT is more sensitive than radiography and does not exhibit the limitations of angiography (i.e., invasiveness, radiation exposure an complex organization. Therefore CT can presently be considered the method of choice in patients with suspected bowel infarction.
1999-04-01
A method of stereotaxic localization adopted for conventional and digital radiography
International Nuclear Information System (INIS)
A method for the determination of stereotaxic coordinates in radiography, e.g. angiography, pneumoencephalography or digital vascular radiography, is described. A special localization frame containing radiopaque structures and scales defines a diagnostic coordinate system. This frame is fixed to the X-ray-table prior to the radiographic procedure and two projections are obtained at arbitrary angles to each other. The focus-film distances do not have to be fixed. The target coordinates are then determined either by a simple graphical procedure or with the use of a digitizing x-y-table, by a computer. With the computer method the films are placed on the digitizing table and the target and a few reference points are marked using a cursor. From the relative positions the computer calculates the coordinates. With the special head fixation system, coordinates of structures visualized in radiographic examinations can be transferred to various therapeutic or diagnostic ...
1986-01-01
International Nuclear Information System (INIS)
Computed tomography (CT) of the neck and mediastinum was performed in 16 patients with renal osteodystrophy. Thirty out of 34 excised parathyroid glands weighing more than 500mg were diagnosed preoperatively (88.2%). Scintigraphy of the neck with _2_0_1TlCl and sup(99m)TcOsub(4-) was also performed in 15 patients. The introduction of subtraction method with a mini-computor in the scintigraphy has remarkably improved the visualization rate of parathyroid glands. Ultrasonic echography (US) of the neck which is able to obtain not only transverse butalso longitudinal imaging was done in 7 patients. It has about same detection rate of the glands with CT. The visualization of enlarged parathyroid glands is valuable not only for localization but also for undeniable evidence of hyperparathyroidism. Also, repeated follow-up examination can determine the effectiveness of conservative treatment. (author).
Power spectrum calculation for the Cornell Wiggler A SASE experiment at BNL
Energy Technology Data Exchange (ETDEWEB)
Recently, we showed (Yu, Phys. Rev. E 58 (1998) 4991) that the widely used simulation code TDA3D, even though a single-frequency code, can be used to determine the power spectrum in the SASE process with excellent approximation in the exponential growth regime. In this paper, we apply this method to the BNL Cornell Wiggler A SASE experiment as an example. When the gain is not very high, there are many modes in the radiation, which seems to make the analytical calculation very difficult. However, we show that the increment of the radiation due to SASE over the spontaneous radiation can be expanded in terms of guided modes with rapid convergence. Thus when the spontaneous radiation is subtracted from the SASE power during the calculation, there is a good agreement between the analytical theory and the numerical simulation.
1999-06-01
Energy Technology Data Exchange (ETDEWEB)
The authors have made new and improved measurements of the neutron capture and total cross sections of {sup 88}Sr at the Oak Ridge Electron Linear Accelerator (ORELA). Improvements over previous measurements include a wider incident neutron energy range, the use of metallic rather than carbonate samples, better background subtraction, reduced sensitivity to sample-dependent backgrounds, and better pulse-height weighting functions. Because of its small cross section, the {sup 88}Sr(n,{gamma}) reaction is an important bottleneck during the s-process nucleosynthesis. Hence, an accurate determination of this rate is needed to better constrain the neutron exposure in s-process models and to more fully exploit the recently discovered isotopic anomalies in certain meteorites. They describe the experimental procedures, compare the results to previous data, and discuss their astrophysical impact.
1998-11-01
British Library Electronic Table of Contents (United Kingdom)
The total photoabsorption cross section on a free proton was measured at the GRAAL facility in the energy range E ? = 600?1500 MeV. The large-aperture LAGRAN?E detector and a liquid hydrogen target were used in the experiment performed with a back-scattered Compton gamma beam. To improve the accuracy, two alternative methods were employed. First, a subtraction method of using empty-target measurements allowed the cross section ? tot to be evaluated directly because of a low level of the electromagnetic background. Second, an algorithm for evaluating ? tot on the basis of summing the dominating partial cross sections was developed. Experimental results obtained for ? tot by the two methods are compared with existing data.
2008-01-01
Image diagnosis of parathyroid glands in chronic renal failure
Energy Technology Data Exchange (ETDEWEB)
Twenty-two out of 31 patients with chronic renal failure and secondary hyperparathyroidism who underwent parathyroidectomy before operation underwent non-invasive image diagnosis of parathyroid glands by computed tomography (CT), scintigraphy with /sup 201/TlCl and /sup 99m/TcO/sup 4 +/, and/or ultrasonography. CT visualized 39 of 45 parathyroid glands (86.7%), weighing more than 500 mg. Scintigraphy with a subtraction method using a computer performed the diagnosis in 19 of 27 glands (70.4%). Ultrasonography detected 21 of 27 glands (77.8%). Image diagnosis was also useful in the postoperative follow-up study. The non-invasive image diagnosis of parathyroid glands in patients with chronic renal failure is thus valuable for 1) definite diagnosis of secondary hyperparathyroidism, 2) localization, and 3) diagnosis for effectiveness of conservative treatment.
1983-07-01
Hybrid Camera Surveillance System Using Robust Human Detection
We propose a novel surveillance system that uses hybrid camera network. The system contains a panorama camera and PTZ cameras to take the wide range images and face images at high enough resolution for identification tasks. The robust human detection methods include robust background subtraction method (RRC), skin color segmentation and face tracking method. First, the system detects persons from a panorama image, and then the detailed face images are obtained with the PTZ cameras. The PTZ cameras can track the faces using the four directional features and the relaxation matching. In addition, the system has automatic camera position calibration feature. Thus, the user can use the system without any troublesome settings.
2007-01-01
Feedwater control device for a reactor
International Nuclear Information System (INIS)
Purpose: To eliminate the water level deviation due to the recycling flowrate, as well as enable a stable control to a reference value even upon changes in the recycling flowrate caused by the variation in the opening degree of a minimum flow valve. Constitution: Reactor recycling system comprises a feedwater pump, a flowrate control valve, a reactor water level detector, and a minimum flow line and a minimum flow valve for preventing the overheating of the feedwater pump at a low flowrate. A flowrate compensator is further disposed, in which a recycling flowrate signal is subtracted from a pump flow rate signal and the result is fedback as a compensated pump flowrate signal. This enables the control system to operate at a rapid response for suppressing the effect of the recycling flowrate as external disturbance, whereby the water level in the reactor can be controlled stably to the reference level and the possibility deviating from an allowable range is decreased ...
1981-11-18
Eddy currents signal processing for steam generator inspection in PWR nuclear power plants
International Nuclear Information System (INIS)
Steam generator tubes in nuclear power plants are periodically checked by means of eddy current probes. The output of a probe is composed of three types of signals: known events (rolling zone, support plates, U-bend part), noise (mainly metallurgical noise) and possible flaws. The latter are random transients, both in arrival time and in shape: they have to be detected and then estimated, before to be fed to the high level stages of a diagnostic system. The objective of the study presented is to develop a semi-automatic system, which could manage and process more than 1 M-bytes of data per tube and provide an operator with reliable diagnostics proposals within a few minutes. This can be achieved only by cooperation of several digital signal processing techniques: detection, segmentation, estimation, noise subtraction, adaptive filtering, modelization, pattern recognition. The paper describes some of these items.
1992-01-01
Digital processing to improve image quality in real-time neutron radiography
Energy Technology Data Exchange (ETDEWEB)
Real-time neutron radiography (NTV) has been used for practical applications at the Kyoto University Reactor (KUR). At present, however, the direct image from the TV system is still poor in resolution and low in contrast. In this paper several image improvements are demonstrated, such as a frame summing technique, which are effective in increasing image quality in neutron radiography. Image integration before the A/D converter has a beneficial effect on image quality and the high quality image reveals details invisible in direct images, such as: small holes by a reversed image, defects in a neutron converter screen through a high quality image, a moving object in a contoured image, a slight difference between two low-contrast images by a subtraction technique, and so on. For the real-time application a contouring operation and an averaging approach can also be utilized effectively.
1985-01-01
Digital processing to improve image quality in real-time neutron radiography
International Nuclear Information System (INIS)
Real-time neutron radiography (NTV) has been used for practical applications at the Kyoto University Reactor (KUR). At present, however, the direct image from the TV system is still poor in resolution and low in contrast. In this paper several image improvements are demonstrated, such as a frame summing technique, which are effective in increasing image quality in neutron radiography. Image integration before the A/D converter has a beneficial effect on image quality and the high quality image reveals details invisible in direct images, such as: small holes by a reversed image, defects in a neutron converter screen through a high quality image, a moving object in a contoured image, a slight difference between two low-contrast images by a subtraction technique, and so on. For the real-time application a contouring operation and an averaging approach can also be utilized effectively. (orig.).
1985-01-01
Application of digital radiography to diagnosis of laryngeal diseases
International Nuclear Information System (INIS)
Fuji Computed Radiography (FCR) is a new system of digital radiography that is based on the latest computer technologies. We applied this FCR system to the X-ray diagnosis of the laryngeal disease. Twenty patients with various laryngeal diseases were evaluated by both FCR frontal tomography and conventional screen-film frontal tomography under the same exposure condition. Both tomograms were then compared on the subject of the clarity of delineation of laryngeal structures. As the result, FCR tomograms revealed the feature of the laryngeal lumen and cartilages more clearly than conventional tomograms. In addition, energy subtraction method, which is one of FCR image processing systems, was presented as a new technical procedure to extinguish cervical spine shadows in plain anteroposterior laryngeal X-photograph. We stress that FCR system is the suitable procedure for X-ray analysis of laryngeal diseases, especially in the region related with the phono-surgery. ...
1986-01-01
Advanced readout integrated circuit signal processing
Readout integrated circuits (ROICs) for focal plane arrays (FPAs) have become increasingly complex to meet the needs of modern infrared systems. BAE Systems has pioneered a number of advanced signal processing architectures for FPA ROICs. Demonstrated signal processing capabilities of BAE Systems FPAs include analog-to-digital conversion, offset subtraction, individual pixel automatic gain compensation, transient noise suppression, on-FPA defect deselection, reconfigurable pixels, spatial neural network processing and subframe noise averaging. BAE Systems FPA advanced signal processing is not just for demonstrations, but is used in many of their deliverable FPAs, improving real system performance.
2006-06-01
Energy Technology Data Exchange (ETDEWEB)
We discuss the renormalisation properties of the complete set of {delta}B=2 four-quark operators with the heavy quark treated in the static approximation. We elucidate the role of heavy quark symmetry and other symmetry transformations in constraining their mixing under renormalisation. By employing the Schroedinger functional, a set of non-perturbative renormalisation conditions can be defined in terms of suitable correlation functions. As a first step in a fully non-perturbative determination of the scale-dependent renormalisation factors, we evaluate these conditions in lattice perturbation theory at one loop. Thereby we verify the expected mixing patterns and determine the anomalous dimensions of the operators at NLO in the Schroedinger functional scheme. Finally, by employing twisted-mass QCD it is shown how finite subtractions arising from explicit chiral symmetry breaking can be avoided completely. (Orig.)
2006-04-15
A comparison between steam injection cycle and combined cycle by energy balance
International Nuclear Information System (INIS)
This paper reports on steam injection cycle which is similar to supplementary fired combined cycle, but for the utilized steam medium produced by HRSG, its temperature is higher and pressure is lower than in the combined cycle. In comparison with the thermodynamic advantage of the two cycles, a clear understanding of physical concept can be gotten simply by energy balance. The difference of total power output between them is subtraction of enthalpy difference of exhaust steam and feed water of HRSG in steam injection cycle from the rejected heat by water coolant of condenser in combined cycle, when using the identical gas turbine and the same amount of total fuel consumption. In general case, formulas and data are given to indicate this comparison by the ratio of steam mass flow supplied by HRSG of the two cycles. The analysis of Cheng Cycle Series 7 is applied as an example to give the practical result.
1989-06-05
International Nuclear Information System (INIS)
Objective: To evaluate the diagnostic value of 64 multidetector-row CT angiography for internal carotid artery (ICA) stenosis and the application in the follow-up of carotid endarterectomy and percutaneous transluminal stenting. Methods: Forty transient ischemic attack (TIA) patients with interpretable CTA and DSA of the cervical carotid arteries were selected from May 2005 to December 2005. This yielded a total of 80 vessels. The CTA curved planar reformations (CPR) and DSA images referenced to the distal cervical internal carotid were graded by two senior neuroradiologists blindly, according to the North American Symptomatic Carotid Endarterectomy Trial (NASCET) guidelines. The paired-t test was used to verify the statistical significant difference between pre-operating and post-operating of carotid endarterectomy or percutaneous transluminal stenting in measuring the vascular diameter and area of cross section using CTA. Results: When the 70% stenosis was used ...
2006-09-01
International Nuclear Information System (INIS)
Purpose: To quantify left ventricular function derived from retrospectively ECG-gated multislice spiral CT (MSCT) data sets in comparison to MRI. Materials and Methods: In 16 patients (14 males, 2 females, mean age 56.8 #+-# 11.5 years), retrospectively ECG-gated MSCT angiography of the coronary arteries and breath-hold steady state free precession cine MRI were performed. From MSCT data-sets, 20 axial image series were reconstructed every 5% of the RR interval. Multiplanar images were reformatted in the short axis orientation from axial images. End-systolic and end-diastolic images were selected. From these images end-systolic volume (ESV), end-diastolic volume (EDV) and stroke volume (SV) as well as the ejection fraction (EF) and myocardial mass (MM) were determined using the Simpson's method and compared with MRI. Furthermore, image quality was assessed for both imaging modalities using a four point grading scale. Results: All parameters were found to have an ...
2003-01-01
Energy Technology Data Exchange (ETDEWEB)
To determine the effectiveness and patency of percutaneous intervention in insufficient native arteriovenous hemodialysis fistulae (AVFs). Between March 1997 and September 2001, 67 cases of insufficient native AVFs resulted from central vein lesion, PTA was performed in 48 cases, and thrombolytic therapy with or without PTA in 11. In eight of the cases, in which central vein stenosis had led to the insufficency, percutaneous transluminal angioplasty (PTA) was performed, and in three of the eight, a stent was inserted. Angiography findings and complications, as well as success and patency rates in the non-thrombosis and thrombosis group, were evaluated; the central vein lesion group was analysed separately. Among 84 lesions observed at angiography, three were 54 cases of stenosis, 17 of occlusion, and 13 of combined thrombosis. The lesions were located in a proximal vein (n=51), distal vein (n=14), artery (n=6), and at the site of anastomosis ...
2002-11-01
Individually weight-adapted examination protocol in retrospectively ECG-gated MSCT of the heart
Energy Technology Data Exchange (ETDEWEB)
The standard protocol in multislice spiral CT (MSCT) angiography for coronary arteries with fixed tube current-time settings leads to an overexposure and thus to an unnecessary high radiation dose in patients with lower weight when compared to heavier patients. The purpose of this study was to estimate the effect of reducing the radiation dose by adapting the tube current-time settings individually. Fifty patients underwent retrospectively ECG-gated MSCT of the heart. In 25 patients (group A{sub 1}) a standard protocol with constant tube current-time settings was used (4 x 1-mm collimation, 120 kV, 400 mAs{sub eff}). Subsequently, artificial image noise was added to the data of these patients simulating a directive for weight-adapted tube current-time settings (group A{sub 2}). In the other 25 patients (group B) an alternative protocol with individually weight-adapted tube current-time settings was applied. The data of all groups were evaluated by a regression ...
2003-12-01
Individually weight-adapted examination protocol in retrospectively ECG-gated MSCT of the heart
International Nuclear Information System (INIS)
The standard protocol in multislice spiral CT (MSCT) angiography for coronary arteries with fixed tube current-time settings leads to an overexposure and thus to an unnecessary high radiation dose in patients with lower weight when compared to heavier patients. The purpose of this study was to estimate the effect of reducing the radiation dose by adapting the tube current-time settings individually. Fifty patients underwent retrospectively ECG-gated MSCT of the heart. In 25 patients (group A_1) a standard protocol with constant tube current-time settings was used (4 x 1-mm collimation, 120 kV, 400 mAs_e_f_f). Subsequently, artificial image noise was added to the data of these patients simulating a directive for weight-adapted tube current-time settings (group A_2). In the other 25 patients (group B) an alternative protocol with individually weight-adapted tube current-time settings was applied. The data of all groups were evaluated by a regression analysis. The ...
2003-12-01
Energy Technology Data Exchange (ETDEWEB)
In rare cases, large adrenal masses with a suspicion of malignancy exhibit tumor extension into the adrenal vein and inferior vena cava. When planning surgery, the relationship of the extension to the inferior vena cava is of decisive improtance. We describe in two cases on the detection of a tumor thrombus in the inferior vena cava arising from a malignant adrenal mass by means of MR angiography (TOF, coronary 2D GRE images [FLASH], 3 slices acquired during 15 second apnea). The angiograms correlated well with the results of DSA venacavography and with the intraoperative findings. Thus, MRA has been demonstrated to be suitable for the certain proof of a venous tumor thrombus not only in cases of renal cell carcinomas but also in cases of malignant adrenal masses. The method should be applied whenever there is evidence of a venous involvement in the adrenal MR images. (orig.) [Deutsch] Grosse malignomverdaechtige Nebennierentumoren zeigen in seltenen Faellen eine ...
1995-11-01
Energy Technology Data Exchange (ETDEWEB)
The aim of this study is three folds: to compare the eight-channel phased-array and standard circularly polarized (CP) head coils in visualiazation of the intracranial vessels, to compare the three-dimentional (3D) time-of-flight (TOF) MR angiography (MRA) techniques, and to define the effects of parallel imaging in 3D TOF MRA. Fifteen healthy volunteers underwent 3D TOF MRA of the intracranial vessels using eight-channel phased-array and CP standard head coils. The following MRA techniques were obtained on each volunteer: (1) conventional 3D TOF MRA with magnetization transfer; (2) 3D TOF MRA with water excitation for background suppression; and (3) low-dose (0.5 ml) gadolinium-enhanced 3D TOF MRA with water excitation. Results are demonstrating that water excitation is a valuable background suppression technique, especially when applied with an eight-channel phased-array head coil. For central and proximal portions of the intracranial arteries, unenhanced TOF MRA ...
2004-11-01
Energy Technology Data Exchange (ETDEWEB)
In relation to considerations on composition of gas produced by coal gasification, the HYCOL hydrogen generation process data were analyzed. From the fact that CO concentration (Y) decreases linearly with CO2 concentration (X), element balance of gasification of reacted coal was used to introduce a reaction analysis equation. The equation includes a term of oxygen excess {Delta}(amount of oxygen consumed for combustion of CO and H2 in excess of the theoretical amount), derived by subtracting the stoichiometric oxygen amount used to gasify coal into CO and H2 from the consumed oxygen amount. The {Delta} can be used as a reference to oxygen utilization efficiency. An equation for the {Delta} was introduced. Also introduced was a term for steam decomposition amount derived by subtracting the generated steam from the supplied steam. These terms may be used as a clue to permeate into the gasifying reaction process. This suggestion was discussed by ...
1996-10-28
Thallium-technetium subtraction parathyroid imaging in patients having previous parathyroid surgery
International Nuclear Information System (INIS)
Parathyroid imaging based on the principle of differential uptakes of Tc-99m and T1-201 in the anterior neck to localize parathyroid (PT) disease has been reported with widely varying results. To evaluate the usefulness of this method, we have performed PT imaging on 47 patients prior to exploratory surgery for PT disease. Using pinhole collimation and digital acquisition, a 50k count image of the thyroid was obtained 20 minutes after injection of 1mCi99m Tc-pertechnetate. Then a lmCi dose of Tl-201 chloride was injected and a series of images acquired for 30 minutes at 30 sec/image. Raw data was spatially filtered and normalized by summing sufficient T1-201 images to equal the Tc-99m image scale of maximum cts/pixel. Image subtraction (Tl-Tc) gave the final PT image. Of 10 pts who had previous neck exploration, all had PT pathology accurately localized by preoperative scanning (7=single adenoma, 2=single hyperplastic gland, 1=two hyperplastic glands). In two ...
1985-06-02
Energy Technology Data Exchange (ETDEWEB)
The purpose of this experiment was to evaluate the diagnostic ability of a CCD-based digital system (CDX-2000HQ) in the detection of incipient dental caries. 93 extracted human teeth with sound proximal surfaces and interproximal artificial cavities were radiographed using 4 imaging methods. Automatically processed No.2 Insight film (Eastman Kodak Co., U.S.A.) was used for conventional radiography, scanned images of conventional radiograms for indirect digital radiography were used. For the direct digital radiography, the CDX-2000HQ CCD system (Biomedisys Co. Korea) was used. The subtraction images were made from two direct digital images by Sunny program in the CDX-2000HQ system. Two radiologists and three endodontists examined the presence of lesions using a five-point confidence scale and compared the diagnostic ability by ROC (Receiver Operating Characteristic) analysis and one way ANOVA test. The mean ROC areas of conventional radiography, indirect digital ...
2003-03-15
International Nuclear Information System (INIS)
The purpose of this experiment was to evaluate the diagnostic ability of a CCD-based digital system (CDX-2000HQ) in the detection of incipient dental caries. 93 extracted human teeth with sound proximal surfaces and interproximal artificial cavities were radiographed using 4 imaging methods. Automatically processed No.2 Insight film (Eastman Kodak Co., U.S.A.) was used for conventional radiography, scanned images of conventional radiograms for indirect digital radiography were used. For the direct digital radiography, the CDX-2000HQ CCD system (Biomedisys Co. Korea) was used. The subtraction images were made from two direct digital images by Sunny program in the CDX-2000HQ system. Two radiologists and three endodontists examined the presence of lesions using a five-point confidence scale and compared the diagnostic ability by ROC (Receiver Operating Characteristic) analysis and one way ANOVA test. The mean ROC areas of conventional radiography, indirect digital ...
2003-03-01
Usefulness of myocardial imaging by [sup 123]I-MIBG in assessment of diabetic neuropathy
Energy Technology Data Exchange (ETDEWEB)
In diabetic patients with autonomic neuropathy, it is suggested that there is a reduced uptake of [sup 123]I-metaiodobenzylguanidine (MIBG) in the heart. We compared the difference of myocardial [sup 123]I-MIBG accumulation between 4 diabetic patients with triopathy and 6 patients without it. In all 10 patients, coronary angiography and [sup 201]Tl imaging (rest and 4 hours later) were performed. [sup 123]I-MIBG (111 MBq) was administered intravenously and its imaging was recorded on 15 minutes and 4 hours after injection. In all 4 cases with triopathy, [sup 123]I-MIBG imaging showed defect in apical and inferior region. In 2 out of 6 cases without triopathy, rapid clearance was noticed in apical and inferior region. There was no significant stenosis in right coronary artery and no defect in initial and delayed [sup 201]Tl images in all cases. We concluded that diabetic autonomic neuropathy in the heart was prominent in apical and inferior region and [sup ...
1993-10-01
Energy Technology Data Exchange (ETDEWEB)
{sup 99m}Tc-N-pyridoxyl-5-methyl-tryptophan (PMT) scintigraphy, which exhibits highly specific for the diagnosis of primary hepatocellular carcinoma (HCC), was performed for recurrent HCC following non-surgical treatment. Eighty-four patients (total 351 examinations) were selected for the study. The ability of PMT scintigraphy to diagnose recurrent HCC after treatment was compared with that of computed tomography, ultrasonography and angiography. The results showed that sixty-three (75%) of 84 cases demonstrated positive findings during our follow-up period, most of the tumors initially showing positive findings remained PMT positive when they recurred and PMT studies shortly after treatment demonstrated wider tracer uptake rather than the actual tumor area. In conclusion, PMT scintigraphy for patients with HCC after non-surgical treatment exhibited high accuracy in identifying viable HCC only for tumors indicating positive findings. (author)
1997-10-01
Localization of abnormal parathyroid glands using thallium-201
Ectopically located parathyroid adenomas may be difficult to find during initial neck exploration. They account for over 70 percent of missed adenomas found at reexploration. Preoperative localization of parathyroid adenomas would reduce unnecessary dissection and possibly reduce the number of negative results of initial neck exploration. Before reoperative parathyroid surgery is performed, some means of localization is mandatory to detect ectopic adenomas in the neck and mediastinum. Computed tomography and ultrasonography cannot effectively evaluate the mediastinum. Angiography and venous parathyroid hormone sampling are invasive, costly, and tedious to perform. We have shown that thallium-201 will accurately localize ectopic parathyroid adenomas. All 10 adenomas found in positions not immediately adjacent to the thyroid gland were detected by thallium-201 scintigraphy. One was a mediastinal adenoma resected with a median sternotomy. Our results suggest that ...
1984-07-01
Energy Technology Data Exchange (ETDEWEB)
Early diagnosis of hepatocellular carcinoma (hepatoma) along with surgical resection is the most appropriate therapeutic modality. For this purpose, there have been many reports concerning the diagnostic value of Lipiodol-CT scan. The authors selected 45 patients with hepatoma during the period of Feb.1986 to Jan. 1988 who received a conventional CT scan, hepatic angiography and a Lipiodol-CT scan. The results were as follows: 1. There was no statistical significant between serum AFP level and mass size, morphology and amount of necrosis. 2. Tumor necrosis was observed in a single massive and multinodular type when the tumor size exceeded 5 cm. 3. Pattern II on Lipiodol-CT, homogenous accumulation of Lipiodol except for the area of inner necrosis, was most frequently demonstrated, which means that a tumor mass with hypervascularity and increased blood flow will attract Lipiodol better. 4. Lipiodol-CT was superior to conventional CT in detecting small, daughter ...
1989-12-15
Diagnosis for the cancer extension of cholangiocarcinoma. The current status
International Nuclear Information System (INIS)
Described is the diagnosis for the cancer extension of cholangiocarcinoma by various imaging techniques and processes to support the current surgical procedure based on preoperative biliary drainage. The cancer tends to locally extend horizontally and/or vertically and its diagnosis is important for surgical indication. For the indication, multi-detector raw CT (MDCT) and MR cholangio-pancreatography (MRCP) are useful and particularly, the former can give multi-phase (arterial, portal and delayed) images to reconstruct multiplanar (MPR) and CT angiographic 3D images, which have made the previous invasive examinations like angiography and percutaneous transportal contrasting unnecessary. MDCT and MRCP can almost complete the diagnosis of the extension. The operative procedure is decided dependently on the site of the lesion, and of which diagnosis, whether it is hepatic hilar/on upper bile duct or middle/lower ductal, is different. MDCT-MPR and MRCP are virtually ...
2010-07-01
International Nuclear Information System (INIS)
We compared the values of the myocardial thickness and the left ventricle diameters measured with MRI and echocardiography. The ejection fraction was compared in MRI and ventriculography. 34 patients with different heart dysfunctions were examined with MRI (FISP 2D sequence). 26 of them were also studied by echocardiography and 20 by biplane cine-ventriculography. The enddiastolic thicknesses of the left ventricular postero-lateral wall and of the septum interventriculare were measured on short axis images. An ellipsoidal modell was used for volume calculation and ejection fraction. Correlation of MRI values of thickness and ejection fraction with echocardiographi and angiographi showed r>0,8. As known for 1.56 T Imagers, the myocardial thickness in MRI was underestimated compared to echocardiography (1.4 mm#+-#1.7). The ejection fraction was underevaluated compared to ventriculography (4.5%#+-#10.1). MRI (1.0 T) accurately measures ventricular wall thickness ...
Computer assisted axial tomography (Emi scan) in neurologic investigation
Cerebral angiography, pneumoencephalography, and radioisotope brain scan with their differing diagnostic abilities have provided the neurologist and neurosurgeon with extremely valuable diagnostic techniques. It is doubtful, however, if any of these now conventional methods had the enormous impact on the practice of neurology that computer assisted axial tomography (C.A.T.) is beginning to have. Here, for the first time, is a test which, without significant risk or discomfort, can demonstrate some normal intracranial (and intraorbital) structures, can demonstrate some normal intracranial pathology and, in many cases, can make the potentially dangerous contrast studies unnecessary. After only a few months experience with C.A.T. in a clinical setting, it has become obvious that there will have to be a reappraisal of the accepted investigative work-up of many conditions. While it is too early to have formulated strict criteria for the use of C.A.T., this paper is an ...
1974-01-01
International Nuclear Information System (INIS)
The tissue distribution of "1"3"1I-transferrin ("1"3"1I-Tf) was studied in athymic nude mice having s.c. human colonic adenocarcinoma HT-29 xenografts. Four days after "1"3"1I-Tf injection, the "1"3"1I specific activity measured in the HT-29 tumor, i.e. amount of radioactivity per gram of fresh tissue, represented 0.31 #+-# 0.09% of the injected radioactivity and was 1.90 fold more than that measured in the murine colon (P < 0.05). After correction for intravascular "1"3"1I-Tf as estimated by mean of "9"9"mTc-Sn in vivo labeling of red blood cells, the "1"3"1I specific activity observed in the HT-29 tumor was 7.21 fold more than that observed in the murine colon. This subtracting method enabled us to localize a HT-29 tumor xenograft by #gamma# scintigraphy of the entire animal and demonstrated that "1"3"1I-Tf could be a non-specific but potent marker for human colon cancer. (author).
The prospects for polarized target materials with pure carbon background
None of the materials presently in common use for polarized proton targets has a pure carbon nuclear background. The alcohols and diols contain some oxygen, and the ammonia and amine-based materials contain nitrogen and/or other noncarbon species. In the latter cases the noncarbon nuclei are measurably polarized as a concomitant of the process used to polarize the hydrogen nuclei. The relative simplicity of a pure carbon background would be advantageous for most types of scattering experiments and perhaps crucial for some. In addition to simplifying the kinematics of background events, pure carbon is relatively easy to prepare as a dummy'' target for background subtraction. Also, in such a target material, [sup 13]C-enrichment would yield a clean polarized [sup 13]C material. In this note I explore the possibilities for such materials, touching upon only what I consider to be the high'' points. The subject matter is capable ...
1992-10-06
The Eighth Data Release of the Sloan Digital Sky Survey: First Data from SDSS-III
Energy Technology Data Exchange (ETDEWEB)
The Sloan Digital Sky Survey (SDSS) started a new phase in August 2008, with new instrumentation and new surveys focused on Galactic structure and chemical evolution, measurements of the baryon oscillation feature in the clustering of galaxies and the quasar Ly{alpha} forest, and a radial velocity search for planets around {approx}8000 stars. This paper describes the first data release of SDSS-III (and the eighth counting from the beginning of the SDSS). The release includes 5-band imaging of roughly 5200 deg{sup 2} in the Southern Galactic Cap, bringing the total footprint of the SDSS imaging to 14,555 deg{sup 2}, or over a third of the Celestial Sphere. All the imaging data have been reprocessed with an improved sky-subtraction algorithm and a final, self-consistent recalibration and flat-field determination. This release also includes all data from the second phase of the Sloan Extension for Galactic Understanding and Evolution (SEGUE-2), consisting of ...
2011-01-01
British Library Electronic Table of Contents (United Kingdom)
Plant meiotic prophase I is a complicated process involving the late zygotene and pachytene stages, both crucial for completing synapsis and recombination. Using David Lily (Lilium davidii var. Willmottiae) as our research material, we performed suppression subtractive hybridization to construct EST library of anthers at various stages of development by the pollen mother cells. From this library, we identified small heat shock protein LimHSP16.45 was highly expressed during the late zygotene to pachytene stages. Our results also showed that LimHSP16.45 was almost specifically expressed in the anther compared with the root, stem, or leaf, and in situ expression of LimHSP16.45 mRNAs showed strong signals in the pollen mother cells and tapetal cells. LimHSP16.45 could be induced by heat and c...
2011-01-01
Scatter measurements for optical cone-beam computed tomography
Energy Technology Data Exchange (ETDEWEB)
Both x-ray and optical cone-beam CT (CBCT) scanners are limited by scattered photons that contaminate the primary images. Transparent radiochromic gels and plastics are anticipated to produce less scattering than polymerization gels and hence result in reconstructed dose distributions with greater contrast and dynamic range. Four methods of scatter measurement were investigated to quantify scatter fractions using an in-house optical CBCT scanner. The methods consisted of generating either 'coin' shadows or primary beamlets in transmission images. The four methods generated similar results of 10% scatter fractions in gel transmission images for this particular scanner configuration with both leuco crystal violet and carbon black micelle gels. The scatter contributions were distributed as 5% from micelle gel, 2% from Teflon wall, 2% from refractive index matching liquid and 1% other sources. Applying a uniform background subtraction of 2% of open ...
2009-05-01
Renormalizability of the functional Schroedinger picture in Robertson--Walker space-time
Energy Technology Data Exchange (ETDEWEB)
We study free and self-interacting scalar quantum field theories in a flat Robertson-Walker metric in the functional Schroedinger picture. We discuss Schroedinger picture quantization, relating it to conventional Heisenberg picture quantization. For the interacting theory, we introduce the time-dependent Gaussian approximation to study time evolution of pure and mixed states and we establish renormalizability of the approximation. We also study the question of computing a finite, renormalized energy-momentum tensor for both the free and the interacting theory in the Gaussian appproximation. Using the adiabatic expansion, we show that the entire subtration necessary to make the the energy-momentum tensor finite in the free theory can be written in terms of covariantly conserved tensors. We further show that the same subtraction is sufficient to make the energy-momentum tensor finite in the Gaussian approximation for the interacting theory provided that the mass and ...
1989-07-01
International Nuclear Information System (INIS)
The Thomsen-Friedenreich (T) antigen, #betta#-D-Gal-(1->3)-#alpha#-D-GalNAc, is exposed in reactive form on many human adenocarcinomata, but not on corresponding benign tissues. Peanut lectin (PNA) has a strong binding affinity for the T antigen and reportedly binds preferentially to certain malignant tissues. We investigated the potential of radio-labelled PNA as a tumour localising agent in an animal model system using a mouse lymphoma (RI) shown to bind fluorescein-labelled PNA in vitro. The radio-iodinated lectin showed good tumour localisation and rapid blood clearance. Clear images of tumours were obtained, in serial scintigraphic imaging, by 24 and 48 h. No blood background subtraction was necessary. Biodistribution studies revealed tumour to blood ratios in mice were 6:1 (at 24 h) and 17:1 (at 48 h), and tumour to muscle ratios were 34:1 (at 24 h) and 40:1 (at 48 h). Rapid in vivo breakdown of _1_2_5I-PNA led to some localisation of free iodide in the ...
1983-01-01
Need for New Optimisation Strategies in CR and Direct Digital Radiography
Energy Technology Data Exchange (ETDEWEB)
Digital imaging techniques such as Digital Image Intensifier Radiography and Digital Storage Phosphor (Selenium) Radiography are replacing conventional film-screen radiography more and more. The aim of this development is the extension of diagnostic capabilities and the reduction of side effects such as radiation dose. Conventional film-screen radiography and digital radiography are very different ways of imaging. For digital radiography specific post-processing is the link between imaging conditions and film documentation. Optimisation of the images includes new possibilities of post-processing and a broad range for variation of the dose. Especially in fluoroscopy, dose can be reduced significantly by new technical features like pulsed fluoroscopy. For digital radiography the European guidelines on quality criteria have to be applied to projection radiography, digital subtraction radiography and to fluoroscopy. Further work should lead to a definition of reference ...
2000-07-01
Need for New Optimisation Strategies in CR and Direct Digital Radiography
International Nuclear Information System (INIS)
Digital imaging techniques such as Digital Image Intensifier Radiography and Digital Storage Phosphor (Selenium) Radiography are replacing conventional film-screen radiography more and more. The aim of this development is the extension of diagnostic capabilities and the reduction of side effects such as radiation dose. Conventional film-screen radiography and digital radiography are very different ways of imaging. For digital radiography specific post-processing is the link between imaging conditions and film documentation. Optimisation of the images includes new possibilities of post-processing and a broad range for variation of the dose. Especially in fluoroscopy, dose can be reduced significantly by new technical features like pulsed fluoroscopy. For digital radiography the European guidelines on quality criteria have to be applied to projection radiography, digital subtraction radiography and to fluoroscopy. Further work should lead to a definition of reference ...
1999-06-13
International Nuclear Information System (INIS)
In this study, a miniature fiber-optic radiation detector has been developed using a water-equivalent organic scintillator for electron beam therapy dosimetry. Usually, two kinds of light signals such as fluorescent and Cherenkov lights are generated in a fiber-optic radiation detector when a high-energy electron beam is irradiated. The fluorescent light signal is produced in the scintillator and is transmitted through a plastic optical fiber to a remote light-measuring device such as a PMT or a photodiode. The Cherenkov light could be also produced in the plastic optical fiber itself and be detected by a light-measuring device. Therefore, it could cause problems or limit the accuracy of the detection of a fluorescent light signal that is proportional to dose. The objectives of this study are to measure, characterize and eliminate Cherenkov light generated in a plastic optical fiber used as a component of a fiber-optic radiation detector and to detect a real fluorescent light signal ...
2007-08-21
Energy Technology Data Exchange (ETDEWEB)
The O({alpha}) electroweak radiative corrections to {gamma}{gamma}{yields}WW{yields}4f within the electroweak standard model are calculated in double-pole approximation (DPA). Virtual corrections are treated in DPA, leading to a classification into factorizable and non-factorizable contributions, and real-photonic corrections are based on complete lowest-order matrix elements for {gamma}{gamma}{yields}4f+{gamma}. Soft and collinear singularities appearing in the virtual and real corrections are combined alternatively in two different ways, namely by using the dipole subtraction method or by applying phase-space slicing. The radiative corrections are implemented in a Monte Carlo generator called Coffer {gamma}{gamma} - the computer code can be obtained from the authors upon request - which optionally includes anomalous triple and quartic gauge-boson couplings in addition and performs a convolution over realistic spectra of the photon beams. A detailed survey of ...
2005-09-01
International Nuclear Information System (INIS)
The O(#alpha#) electroweak radiative corrections to #gamma##gamma##->#WW#->#4f within the electroweak standard model are calculated in double-pole approximation (DPA). Virtual corrections are treated in DPA, leading to a classification into factorizable and non-factorizable contributions, and real-photonic corrections are based on complete lowest-order matrix elements for #gamma##gamma##->#4f+#gamma#. Soft and collinear singularities appearing in the virtual and real corrections are combined alternatively in two different ways, namely by using the dipole subtraction method or by applying phase-space slicing. The radiative corrections are implemented in a Monte Carlo generator called Coffer #gamma##gamma# - the computer code can be obtained from the authors upon request - which optionally includes anomalous triple and quartic gauge-boson couplings in addition and performs a convolution over realistic spectra of the photon beams. A detailed survey of ...
2005-09-01
Energy Technology Data Exchange (ETDEWEB)
This report describes the fiscal 1998 result on development of genome informatics technology. As comparative analysis technique of genes, the combination of electrophoresis and PCR was used. For improvement of the throughput and reproducibility of the technique, module- shuffling primers were used, and the multi(96)-arrayed capillary fragment analyzer was devised. The system detecting SNPs rapidly was also developed successfully. As analysis technology of DNA sequence by use of triple- stranded DNA formation, study was made on construction of long cDNA libraries, selective subtraction of specific sequences from libraries, and the basic technology of homologous cloning. Study was also made on each reaction step of IGCR technique for fast analysis, and specifications of a fluorescence transfer monitor. As modeling technique of genetic sequence information, the simulation model was developed for gene expression regulatory networks during muscle differentiation, and ...
1999-03-01
Energy Technology Data Exchange (ETDEWEB)
Steam generator tubes in nuclear power plants are periodically checked by means of eddy current probes. The output of a probe is composed of three types of signals: known events (rolling zone, support plates, U-bend part), noise (mainly metallurgical noise) and possible flaws. The latter are random transients, both in arrival time and in shape: they have to be detected and then estimated, before to be fed to the high level stages of a diagnostics system. The objective of the study presented is to develop a semi-automatic system, which could manage and process more than 1 M-bytes of data per tube and provide an operator with reliable diagnostics proposals within a few minutes. This can be achieved only by cooperation of several digital signal processing techniques: detection, segmentation, estimation, noise subtraction, adaptive filtering, modelization, pattern recognition. The paper describes some of these items.
1991-07-01
Energy Technology Data Exchange (ETDEWEB)
Steam generator tubes in nuclear power plants are periodically checked by means of eddy current probes. The output of a probe is composed of three types of signals: known events (rolling zone, support plates, U-bend part), noise (mainly metallurgical noise) and possible flaws. The latter are random transients, both in arrival time and in shape: they have to be detected and then estimated, before to be fed to the high level stages of a diagnostic system. The objective of the study presented is to develop a semi-automatic system, which could manage and process more than 1 M-bytes of data per tube and provide an operator with reliable diagnostics proposals within a few minutes. This can be achieved only by cooperation of several digital signal processing techniques: detection, segmentation, estimation, noise subtraction, adaptive filtering, modelization, pattern recognition. The paper describes some of these items.
1992-01-01
Energy Technology Data Exchange (ETDEWEB)
The fluxes of atmospheric electrons, positrons, positive and negative muons and negative pions have been determined using the NMSU Wizard-MASS2 balloons-borne instrument. The instrument was launched from Fort Sumner, New Mexico, (geomagnetic cut-off about 4.5 GV/c) on september 23, 1991. The flight lasted 9.8 hours and remained above 100.000 ft. Muons and negative pions were observed and their momenta were determined. Since these particles are not a part of the primary component, the measurement of their fluxes provides information regarding production and propagation of secondary particles in the atmosphere. Similarly, observations of electrons and positrons well below the geomagnetic cut-off provides insight into electromagnetic cascade processes in the upper atmosphere. In addition, the determination of the energy spectra of rare particles such as positrons can be used for background subtraction for cosmic ray experiments gathering data below a few g/cm{sup 2} ...
1995-09-01
Energy Technology Data Exchange (ETDEWEB)
Stainless steel is pickled in pickling bath with the sulfuric acid and a mixture of hydrofluoric acid and nitric acid. Suitable equipment based on speedy and accurate chemical analysis for actual production lines has not been developed yet. The concentration of sulfuric acid can be analyzed by using the neutralization titration method. As a method of analyzing hydrofluoric acid in the mixed acid, the iron-acetylacetone complex discoloration absorbance method was adopted. For the concentration, of nitric acid, the method of subtracting the concentration of hydrofluoric acid from the total mixed acid amounts obtained by neutralization titration is adopted. Furthermore, the iron-salicylic acid complex absorbance method is adopted as a method of analyzing the iron content. By adopting these methods, the fully automated analyzer is developed. Completing analysis work can be shortened to 40 minutes by automated sampling from the acid pipes. The fully automated acid ...
1999-01-10
Clinical trial of NMR-CT, (4). Clinical evaluation of hybrid image
Energy Technology Data Exchange (ETDEWEB)
In our evaluation we utilized the Asahi Mark-J NMR-CT system, with a resistive vertical quadrupolar electromagnet (0.1 Tesla) and a proton resonance frequency of 4.5 MHz. Our main imaging methods are the inversion-recovery or IR, saturation-recovery, or SR, and calculated T/sub 1/. Difference, or D images, constructed by subtracting the data of the IR signal from that of the SR signal, have also been obtained in some cases. The system allows averaging of raw data. Hybrid images were constructed from two or more images to obtain clear definition of areas of interest. By using the hybrid image, several tissues of different relaxation times can be shown in the same image. Application in our study of the newly developed hybrid image indicates its importance in the detection and diagnosis of lesion, especially the detection of the differentiation of an edematous lesion from a tumor, and also abnormal fluid collection such as the pleural effusion or ascites. We hope that ...
1985-01-01
The vertical profiles of disc galaxies are built by the material trapped around stable periodic orbits, which form their "skeletons". According to this, the knowledge of the stability of the main families of periodic orbits in appropriate 3D models, can predict possible morphologies for edge-on disc galaxies. In a pilot survey we compare the orbital structures which lead to the appearance of "peanuts" and "X"-like features with the edge-on profiles of three disc galaxies (IC 2531, NGC 4013 and UGC 2048). The subtraction from the images of a model representing the axisymmetric component of the galaxies reveals the contribution of the non-axisymmetric terms. We find a direct correspondence between the orbital profiles of 3D bars in models and the observed main morphological features of the residuals. We also apply a simple unsharp masking technique in order to study the sharpest features of the images. Our basic conclusion is that the morphology of the boxy "bulges" ...
2006-01-01
Asymptotic numbers and wave packets
International Nuclear Information System (INIS)
An attempt is made to generalize the spaces of numbers and functions in order to consider certain problems in quantum mechanics, especially in the cases, where wave functions appear which do not belong to the Hilbert space L"2. Often the Soboljev - Schwartz distributions are used but they are not always the appropriate tool because they cannot be multiplied. A modification of the definition of generalized functions PSI(x vector) is proposed by particular conditions. Such conditions imposed on the wave function of a free particle seems to be the most natural by means of physics. It appears, however, that for all spaces with a real norm these conditions are contradictory. This implies together with the extension of the space of functions, an extension of the space of numbers with so called asymptotic numbers A. The four algebraic operations - addition, subtraction, multiplication and division are defined in the set A. To avoid the contradictions between the ...
1976-01-26
Energy Technology Data Exchange (ETDEWEB)
The previous judgment of eutrophic state, once proposed for the Trasimeno Lake (Umbria region, Italy), has been revised. According to Vollenweider-OECD classification criterion, the lake waters are at present to be classified as mesotrophic waters, with phosphorus limitation. However this level of moderate productivity results to be conditioned by the hydrochemical characteristics of the lake waters, that control phosphorus concentrations independently from the loading coming from the basin, and prevent dangerous and massive algal blooms. Different processes of chemical nature, regulating the phosphorus amount in the lake waters, are then reviewed: adsorption of P/P0(4) onto suspended materials, particularly clay mineral particles, and direct precipitation as hydroxylapatite or co-precipitation with carbonates, are found to be the principal mechanisms that determine chemical removal of phosphorus from the water column. A preliminary mass balance of phosphorus ...
1995-06-01
What is the best contrast injection protocol for 64-row multi-detector cardiac computed tomography?
International Nuclear Information System (INIS)
Objective: To determine the optimal contrast injection protocol for 64-MDCT coronary angiography. Materials and methods: One hundred and fifty consecutive patients scheduled to undergo retrospectively electrocardiographically gated 64-MDCT. Each 30 patients were assigned to use a different contrast protocol: group 1: uniphasic protocol (contrast injection without saline flush); group 2: biphasic protocol (contrast injection with saline flush); group 3A, 3B and 3C: triphasic protocol (contrast media + different saline diluted contrast media + saline flush). Image quality scores and artifacts were compared and evaluated on both transaxial and three-dimensional coronary artery images among each contrast protocol. Results: Among the triphasic protocol groups, group 3A (30%:70% contrast media-saline mixture was used in second phase) used the least contrast media and had the least frequency of streak artifacts, but there were no significant differences in coronary artery ...
2010-08-01
International Nuclear Information System (INIS)
The objective of this study was to explore the role of three-dimensional (3-D) rotational angiography (RA) of the inferior vena cava (IVC; 3-D CV) before filter retrieval and its impact on treatment planning compared with standard anteroposterior cavography (sCV). Thirty patients underwent sCV and 3-D CV before IVC filter retrieval. Parameters assessed were: projection of filter arms or legs beyond the caval lumen, thrombus burden within the filter and IVC, and orientation of the filter within IVC. Skin and effective radiation doses were calculated. Statistical analysis was performed using paired Student t test and nonparametric McNemar's test. Standard anteroposterior cavography detected 49 filter arms or legs projecting beyond the caval lumen in 25 patients. Three-dimensional CV demonstrated 89 filter arms or legs projecting beyond the caval lumen in 28 patients. Twenty-two patients had additional filter arms or legs projecting beyond the caval lumen detected on ...
2009-01-01
Energy Technology Data Exchange (ETDEWEB)
Purpose: To determine the value of MRI in the postoperativ evaluation of a singular ventricle compared to echocardiography and cardiac catheterization. Materials and methods: Thirty-one patients (range: 6 months to 30 years) with a functional single ventricle following palliative corrective operations. Five patients had a Blalock-Taussig-Shunt, 8 patients a Glenn-Anastomosis and 18 a cavopulmonary shunt (6 with classic Fontan-Circulation, 12 with modified cavopulmonary anastomosis). The results in terms of postoperative morphologic changes were compared to percutaneous echocardiography (31/31) and cardiac catheterization (6/31). Results: Echocardiography, which was performed on all patients, could not visualize the entire length of the tunnel, the Glenn-Anastomosis or the central pulmonary arteries in 70% of the patients due to an inadequate acoustic window. MRI was able to show the entire tunnel in 11/12 patients and the central pulmonary arteries in 30/31 patients. The exact anatomy ...
2002-12-01
64-slice multidetector coronary CT angiography: in vitro evaluation of 68 different stents
Energy Technology Data Exchange (ETDEWEB)
The purpose of this study was to test a large sample of different coronary artery stents using four image reconstruction approaches with respect to lumen visualization, lumen attenuation, and image noise in 64-slice multidetector-row computed tomography (MDCT) in vitro and to provide a catalogue of currently used coronary artery stents when imaged with state-of the-art MDCT. We examined 68 different coronary artery stents (57 stainless steel, four cobalt-chromium, one cobalt-alloy, two nitinol, four tantalum) in a coronary artery phantom (vessel diameter 3 mm, intravascular attenuation 250 HU, extravascular density -70). Stents were imaged in axial orientation with standard parameters: 32x0.6 collimation, pitch 0.24, 680 mAs, 120 kV, rotation time 0.37 s. Four different image reconstructions were obtained with varying convolution kernels and section thicknesses: (1) soft, 0.6 mm, (2) soft, 0.75, (3) medium soft, 0.6, and (4) stent-optimized sharp, 0.6. To evaluate visualization ...
2006-04-15
International Nuclear Information System (INIS)
The aim of this study was to document vascular complications that occurred following cadaveric and living donor kidney transplants in order to assess the overall incidence of these complications at our center as well as to identify possible risk factors. In a retrospective cohort study, 1500 consecutive renal transplant recipients who received a living or cadaveric donor kidney between December 1988 and July 2006 were evaluated. The study was performed at the Nemazee Hospital, Shiraz, Iran. The assessment of the anatomy and number of renal arteries as well as the incidence of vascular complications was made by color doppler ultrasonography, angiography, and/or surgical exploration. Clinically apparent vascular complications were seen in 8.86% of all study patients (n = 133) with the most frequent being hemorrhage (n = 91; 6.1%) followed by allograft renal artery stenosis (n = 26; 1.7%), renal artery thrombosis (n = 9; 0.6%), and renal vein thrombosis (n = 7; 0.5%). ...
Unsolved problems in the diagnosis and surgical treatment of intramedullary tumors
Energy Technology Data Exchange (ETDEWEB)
Problems and solutions in the diagnosis and operative treatment were clarified by retrospective evaluation of cases of intramedullary tumor in which MRI and surgery had been performed. The subjects were 16 patients (21-75 years old, mean age: 45 years) whose tumor was surgically removed between 1991 and 1998. MRI was performed preoperatively, and T1-weighted images, T2-weighted images, and enhanced images were obtained. Angiography was also performed in some cases. The histological diagnosis based on the MRI findings before surgery were compared with the pathological diagnosis after the operation. In 9/16 cases (56%), the preoperative histological diagnosis based on the MR images was the same as the pathological diagnosis after the operation. In 8 of the 11 cases (73%) whose images showed clear tumor margins and well shaped the tumor, the tumors were completely removed. The concordance rate between the pathological diagnosis during and after the operation was 67%. ...
2001-04-01
International Nuclear Information System (INIS)
The aim of the study was the attempt to evaluate the influence of two different methods of cardiac perfusion SPECT reconstruction (FBP and ITW) on clinical efficacy in diagnosing the coronary artery disease as well as the cardiac ischemia detection in three areas of heart vascularized by main coronary arteries: LAD, LCX and RCA with the use of artificial neural networks (ANN). The study was performed retrospectively with the use of the diagnostic image records as well as clinical dataset of 43 patients. Myocardial perfusion stress/rest SPECT study and X-ray coronarography data were evaluated for each patient. The results of coronary angiography were considered the reference method. The cardiac SPECT data were reconstructed using the two different methods: filtered backprojection (FBP) and iterative Wallis method (ITW). The local perfusion deficits denominated in stress and rest study in three main vessel cardiac segments were the main input values for the ANN. The ...
Energy Technology Data Exchange (ETDEWEB)
We wanted to evaluate the status of self-expandable nitinol stents implanted in the P2 and P3 segments of the popliteal artery in Korean patients. We retrospectively analyzed 189 consecutive patients who underwent endovascular treatment for steno occlusive lesions in the femoropopliteal artery from July 2003 to March 2009, and 18 patients who underwent stent placement in popliteal arterial P2 and P3 segments were finally enrolled. Lesion patency was evaluated by ultrasound or CT angiography, and stent fracture was assessed by plain X-rays at 1, 3, 6 and 12 months and annually thereafter. At the 1-month follow-up, stent fracture (Type 2) was seen in one limb (up to P3, 1 of 18, 6%) and it was identified in seven limbs at the 3-month follow-up (Type 2, Type 3, Type 4) (n = 1: up to P2: n = 6: P3). At the 6-month follow-up, one more fracture (Type 1) (up to P3) was noted. At the 1-year follow-up, there were no additional stent fractures. Just four limbs (up to P2) at ...
2011-04-15
International Nuclear Information System (INIS)
To evaluate the radiological patterns of vascular invasion in peripheral cholangiocarcinomas. Hepatic arteriography and portography in 20 cases with cholangiocarcinoma including 12 cases with angiographic CT were retrospectively analyzed. The arteriography showed no arterioportal shunt, hypertrophy of tumor vessel, or tumor staining extending to central portion of the mass in all cases. However, doughnut shaped peripheral tumor staining was seen until late hepatogram phase in 12 cases and compensatory hyperperfusion around the mass was seen in six cases (eight cases if include arterial CT). Encasement of tumor vessel was seen in 12 cases, and hypertrophy of feeding vessel in nine cases. On portography, the filling defect on segmental portal branch could be demonstrated only in 11 cases. Shape of the portal defect was tapered narrowing in six cases, abrupt narrowing in two cases but intraluminal nodular filling defect was not seen. Remaining three cases were difficult to define the ...
1995-01-01
Multidetector-row helical CT: analysis of time management and workflow
International Nuclear Information System (INIS)
The purpose of this study was to evaluate time management and workflow for multidetector-row helical CT (MDCT). Time for patient and data handling of at total of 580 patients were evaluated at two different time periods (December 1999, August 2000), each for the following baseline measurements: (a) change of clothes/instruction; (b) patient placement on the CT table/i.v. catheter; (c) CT planning and programming; (d) CT data acquisition; (e) CT data reconstruction; (f) CT data storage/printing. All imaging was performed on a Somatom Volume Zoom (Siemens, Erlangen, Germany). Time measurements summarized for different CT protocols revealed the following: (a) 5:01 min (#+-#2.06 min); (b) 4:36 min (#+-#2.43 min); (c) 4:11 min (#+-#2.55 min); (d) 0:43 min (#+-#0.15 min); (e) 6:59 min (#+-#2.39 min); (f) 09:51 min (#+-#3.51 min). Planning and programming was most time-consuming for CT angiography, whereas chest and abdominal CT needed only 3:26 and 3:30 min, ...
2002-03-01
International Nuclear Information System (INIS)
The frequency of peripheral pulmonary artery stenosis in patients after surgical repair of tetralogy of Fallot (TOF) ranges from 20 to 40%. This can be either primary or secondary to the surgical intervention. The influence of resulting lung perfusion alterations on the life quality of patients is difficult to predict. The aim of this study was to compare the utility of the diagnostic procedures in this group of patients, with particular focus on lung perfusion scintigraphy. This study comprised 104 patients who underwent repair of TOF at ages from 5 months to 25 years. The patients have been followed up for from 4.2 to 25 years. On the basis of chest X-ray peripheral pulmonary artery stenosis was suspected in 11 patients, in 12 on the basis of echocardiography examination. Lung perfusion scintigraphy has been performed on 87 patients. The disturbances in lung perfusion (mostly in the left lung) were show by means of lung perfusion scintigraphy in 43 (49%) of patients. In 27 of them ...
Imaging of coronary artery stents using multislice computed tomography: in vitro evaluation
Energy Technology Data Exchange (ETDEWEB)
The aim of this study was to evaluate imaging features of different coronary artery stents during multislice CT Angiography (MSCTA). Nineteen stents made of varying material (steel, nitinol, tantalum) and of varying stent design were implanted in plastic tubes with an inner diameter of 3 mm to simulate a coronary artery. The tubes were filled with iodinated contrast material diluted to 200 Hounsfield units (HU), closed at both ends and positioned in a plastic container filled with oil (-70 HU). The MSCT scans were obtained perpendicular to the stent axes (detector collimation 4 x 1 mm, table feed 2 mm/rotation, 300 mAs, 120 kV). Axial images and multiplanar reformations were evaluated regarding artifact size, lumen visibility, and intraluminal attenuation values. Artifacts characterized by artifactual thickening of the stent struts leading to apparent reduction in the lumen diameter and increased intraluminal attenuation values were observed in all cases. The stent ...
2003-04-01
Energy Technology Data Exchange (ETDEWEB)
Hemodynamic characteristics were studied by using in vivo vascular imaging techniques in 17 resected early stage hepatocellular carcinoma (e-HCC) by comparing them with 49 resected advanced HCCs (ad-HCC) less than 3 cm in diameter. In this study, e-HCC was defined as the nodule being uniformly composed of well-differentiated HCC or adenomatous hyperplastic nodule containing well-differentiated HCC foci within the nodule. In vivo vascular imaging techniques are as follows; US angiography with intraarterial CO{sub 2} microbubbles were performed to assess the tumor arterial vascularity, and CT during arterial portography (CTAP) was performed to assess the portal perfusion within the nodule. Of 17 e-HCC nodules 5 were hypervascular, 5 were isovascular, 4 were hypovascular, and 3 were vascular spot in hypovascular pattern in contrast to 49 ad-HCC nodules, 43 of which were hypervascular and 6 were isovascular. Of 14 e-HCCs, 9 nodules showed perfusion defect and 5 did not ...
1992-04-01
Energy Technology Data Exchange (ETDEWEB)
The purpose of this study was to assess the effect of adenosine-triphosphate (ATP) on hemodynamics and left ventricular (LV) function, and to examine the value of ATP radionuclide-ventriculography (RNVG) for detecting coronary artery disease (CAD) in comparison with standard exercise RNVG. Thirty-eight consecutive patients with suspected CAD underwent ATP (0.18 mg/Kg/min) RNVG and symptom-limited exercise RNVG. Coronary angiography revealed 27 patients with CAD (Group S) and 11 without CAD (Group N). In group S, exercise induced an increase in LV end-diastolic volume (LVEDV) and LV end-systolic volume (LVESV), and a decrease in LV ejection fraction (LVEF). In contrast, ATP infusion caused LVESV to decrease in both groups, improving LVEF. Only 14 of 39 segments whose wall motion was deteriorated by exercise showed worsening regional wall motion during ATP infusion. The sensitivity and specificity of ATP RNVG for detecting CAD were 22. 2% and 100%, while those of ...
1995-07-01
Energy Technology Data Exchange (ETDEWEB)
Bowel infarction is a rare and typical condition of the elderly; despite improvements in diagnostic imaging and vascular surgery, bowel infarction remains a major cause of acute abdomen, with mortality rates ranging 70-80%. Diagnosis on often late because clinical signs, laboratory data and radiologic findings are a specific. The authors investigated radiographic and particular CT patterns of intestinal infraction in 56 patients submitted to surgery within 12 hours of admission. We also report the CT findings of 5 of these patients who had reversible mesenteric ischemia. CT is more sensitive than radiography and does not exhibit the limitations of angiography (i.e., invasiveness, radiation exposure and complex organization). Therefore CT can presently be considered the method of choice in patients with suspected bowel infarction. [Italian] L'infarto intestinale rappresenta una malattia rara e tipica del soggeto anziano; nonostante il notevole ...
1999-04-01
Energy Technology Data Exchange (ETDEWEB)
Hyaluronate (HA) distribution patterns were examined in the cranial mesenchyme underlying the mesencephalic neural folds of mouse embryos maintained in roller tube culture. Using standard image-processing techniques, the digitized images of Alcian blue-stained or 3H-glucosamine-labeled sections digested with an enzyme specific for HA, were subtracted from adjacent, undigested sections. The resultant difference picture images (DPI) accurately depicted the distribution of stained or labeled HA within the cranial mesenchyme. 3H-glucosamine-labeled HA was distributed uniformly throughout the cranial mesenchyme as 12, 18, and 24 hr of culture. By contrast, the mesenchyme was uniformly stained with Alcian blue at 12 hr, but stain intensity decreased in the central regions of the mesenchyme at 18 and 24 hr. HA distribution patterns were also examined in the cranial mesenchyme of embryos cultured in the presence of diazo-oxo-norleucine (DON), a glutamine analogue that ...
1990-06-01
Sources of toxicity and exposure information for identifying chemicals of high concern to children
International Nuclear Information System (INIS)
Due to the large number of chemicals in commerce without adequate toxicity characterization data, coupled with an ineffective federal policy for chemical management in the United States, many states are grappling with the challenge to identify toxic chemicals that may pose a risk to human health and the environment. Specific populations (e.g., children, elderly) are particularly sensitive to these toxic chemicals. In 2008, the Children's Safe Product Act (CSPA) was passed in Washington State. The CSPA included specific requirements to identify High Priority Chemicals (HPCs) and Chemicals of High Concern to Children (CHCCs). To implement this legislation, a methodology was developed to identify HPCs from authoritative scientific and regulatory sources on the basis of toxicity criteria. Another set of chemicals of concern was then identified from authoritative sources, based on their potential exposure to children. Exposure potential was evaluated by identifying chemicals detected in ...
2010-11-01
Natural and anthropogenic "1"4C in the UK coastal marine environment
International Nuclear Information System (INIS)
Prior to this study, almost no up-to-date information was available on the 'background' level of "1"4C present in the water and biota of the UK coastal marine environment. The weighted mean "1"4C activity derived from the lowest activities of dissolved inorganic carbon (DIC) and biota for sites which are remote from potential sources is 247#centre dot#6#+-#1#centre dot#0 Bq kg"-"1 carbon. This is proposed as the best estimate of the natural/weapons testing 'background' for 1995 and should be subtracted from the activity derived for any sample to establish the excess due to UK anthropogenic inputs. "1"4C activities in the DIC component of seawater and a range of marine biota are significantly enhanced above the expected 'background' value in the environment around the British Nuclear Fuels plc reprocessing plant at Sellafield, Cumbria, NW England and Amersham International plc, Cardiff, Wales. The enrichments around Sellafield are largely confined to the NE Irish ...
1997-07-01
Measuring q sub 0 using supernovae at z approx 0. 3
Energy Technology Data Exchange (ETDEWEB)
The measurement of q{sub o} is extremely important for understanding the quantity of matter in our universe. The measurement of q{sub o} using supernovae of type Ia as standard candles is appealing because it requires less modeling than other methods using galaxies. The challenge with using supernovae to measure q{sub o} is in finding enough of them. In order to find supernovas, we have constructed a very popular f/1 camera for the 3.9m Anglo-Australian Telescope. The camera uses reducing optics that put a 17 in. {times} 17 in. field on a 1024 {times} 1024 pixel Thomson CCD. Using this system, we image to 23rd magnitude in five minutes. We have developed a software package that uses image subtraction to find supernovae that are approximately magnitude 22.4 or brighter in these images. One field can be processed every 6.6 minutes on a relatively unloaded VAX 6000-6510. We estimate that this system should find one supernova in every 105--139 images (about two nights ...
1992-07-01
Energy Technology Data Exchange (ETDEWEB)
The effect that different chemical and physical atomic environments can have on the relative intensities of radiative electron transitions from the filling of K shell vacancies was investigated. The method used involved the detection of photoionization induced X-ray fluorescence. An experimental system based on a hyper pure germanium detector (HPGE) was used to measure the relative K-L and K-M X-ray yields from the photofluorescence of a series of lanthanide elements and compounds. A background subtraction and peak integration strategy was employed which accounted for scattering in the samples and scattering of the flux from the radioisotope photoionization sources. Analysis of the data resulted in a tabulation of relative K/sub ..beta..//K/sub ..cap alpha../ X-ray intensity ratios. The measured relative K/sub ..beta..//K/sub ..cap alpha../ X-ray intensity ratios were compared to the calculated values predicted by the theoretical development of Scofield and the ...
1987-01-01
International Nuclear Information System (INIS)
The effect that different chemical and physical atomic environments can have on the relative intensities of radiative electron transitions from the filling of K shell vacancies was investigated. The method used involved the detection of photoionization induced X-ray fluorescence. An experimental system based on a hyper pure germanium detector (HPGE) was used to measure the relative K-L and K-M X-ray yields from the photofluorescence of a series of lanthanide elements and compounds. A background subtraction and peak integration strategy was employed which accounted for scattering in the samples and scattering of the flux from the radioisotope photoionization sources. Analysis of the data resulted in a tabulation of relative K/sub #beta#//K/sub #alpha#/ X-ray intensity ratios. The measured relative K/sub #beta#//K/sub #alpha#/ X-ray intensity ratios were compared to the calculated values predicted by the theoretical development of Scofield and the average of previous ...
1987-01-01
K and L x-ray production cross sections excited by 14.00--34.16 MeV #alpha#-particle beams
International Nuclear Information System (INIS)
K and L-shell x-ray production cross sections were measured using #alpha#-particle beams of 14.00 to 34.16 MeV. The K-shell measurements ranged from Z = 20 to Z = 50 and included Ca, Sc, Ti, V, Fe, Ni, Cu, Zn, Ga, Br, Rb, Sr, Y, Mo, Ag, In, and Sn while the L-shell measurements ranged from Z = 55 to Z = 92 and included Cs, Ba, Ce, Gd, Tm, Lu, Au, Pb, Th, and U. Thin metallic foils were used for the measurements and corrections for self-attenuation were negligible. A liquid nitrogen cooled Si(Li) detector and associated pulsed optical electronics were used in detecting x-rays. Absolute cross sections with an uncertainty of +-10 percent are presented for the elements measured. Also smoothed cross sections are presented which were generated by a three term polynomial fit of the experimental data points. By use of available fluorescence yields the K-shell data were converted to ionization cross sections and compared to various theoretical models. The data suggest the necessity for high ...
Energy Technology Data Exchange (ETDEWEB)
ICP emission analyses are prone to errors due to changes in power level, nebulization rate, plasma temperature, and sample matrix. As a result, accurate analyses of complex samples often require frequent bracketing with matrix matched standards. Information needed to track and correct the matrix errors is contained in the emission spectrum. But most commercial software packages use only the analyte line emission to determine concentrations. Changes in plasma temperature and the nebulization rate are reflected by changes in the hydrogen line widths, the oxygen emission, and neutral ion line ratios. Argon and off-line emissions provide a measure to correct the power level and the background scattering occurring in the polychromator. The authors` studies indicated that changes in the intensity of the Ar 404.4 nm line readily flag most matrix and plasma condition modifications. Carbon lines can be used to monitor the impact of organics on the analyses and calcium and argon lines can be ...
1997-10-01
Gaussian pulse decomposition: an intuitive model of electrocardiogram waveforms.
This study presents a novel approach to modeling the electrocardiogram (ECG): the Gaussian pulse decomposition. Constituent waves of the ECG are decomposed into and represented by Gaussian pulses using an iterative algorithm: the chip away decomposition (ChAD) algorithm. At each iteration, a nonlinear minimization method is used to fit a portion of the ECG waveform with a single Gaussian pulse, which is then subtracted from the ECG waveform. The process iterates on the resulting residual waveform until the normalized mean square error is below an acceptable level. Three different minimization methods were compared for their applicability to the ChAD algorithm; the Nelder-Mead simplex method was found to be more noise-tolerant than the Newton-Raphson method or the steepest descent method. Using morphologically different ECG waveforms from the MIT-BIH arrhythmia database, it was demonstrated that the ChAD algorithm is capable of modeling not only normal beats, but ...
International Nuclear Information System (INIS)
The concentration of trace elements in brain sections was measured by synchrotron radiation X-ray fluorescence. The relative concentration was calculated by means of the normalization of Compton scattering intensity approximately 22 keV, after the normalization for collecting time of X-ray spectrum and the counting of the ion chamber, and subtracting the contribution of the polycarbonate film for supporting sample. Furthermore, the statistical evaluation of the element distribution in various regions of the brain sections of the 20-day-old rats was tested. For investigating the distribution of elements in the brain of iodine deficient rats, Wistar rats were fed with iodine deficient diet and deionized water (ID group). The rats were fed the same iodine deficient diet, but drank KIO_3 solution as control (CT group). The results showed that the contents of calcium (Ca) in thalamus (TH) and copper (Cu) and iron (Fe) in cerebral cortex (CX) of ID rats were ...
2004-02-27
Brain SPECT of chronic fatigue syndrome (CFS): SPM analysis of two age groups
International Nuclear Information System (INIS)
Full text: Chronic fatigue syndrome (CFS) is a complex disorder characterised by profound fatigue and neuropsychiatric dysfunction. Previous studies with cerebral perfusion SPECT (rCBF) scans were performed with inhomogeneous patient populations and were not analysed with Statistical Parametric Mapping (SPM). We have used SPM to study subjects with moderate CFS based on the Fukuda criteria, who were not on medication and not depressed, compared to age matched control subjects. An apparent bimodal age distribution has been observed in CFS. Subjects were therefore divided into two age groups: 16-35 or under 35 (17 CFS, 11 control) and 36-61 or over 35 (15 CFS, 15 control). HMPAO brain SPECT was acquired on a 3-head camera. After lower window scatter subtraction, reconstruction with attenuation correction (mu=0.15/cm) and editing of facial activity, scans were spatially normalised (affine + 2x3x2 nonlinear) to SPM's anatomical space. SPM statistical analysis yielded ...
2002-05-04
Absence of isoscalar monopole strength in {sup 56}Fe and {sup 58}Ni
Energy Technology Data Exchange (ETDEWEB)
Measurements with 240 MeV {alpha} particle inelastic scattering with excellent peak/background ratios at small scattering angles including 0{degrees} were made on {sup 56}Fe and {sup 58}Ni using the multipole-dipole-multipole spectrometer at Texas A&M University. Beam was delivered to the spectrometer through a beam analysis system having two bends of 88{degrees} and 87{degrees} respectively. A slit placed after the first 88{degrees} bend was used to define the beam. Slits placed after the second bend (87{degrees}) were used to eliminate slit scattered particles. Comparison of the results of a multiple peak fit to the{sup 58}Ni spectra after continuum subtraction to DWBA calculations revealed about 32% of the E0 EWSR and 58% of the E2 EWSR in the peak, in agreement with previous works. Fits to the angular distribution of the continuum for E{sub x} = 25 MeV show that <15% of the E0 EWSR is present in the continuum. Hence 50% of the EO EWSR must lie above ...
1995-10-01
Liver trauma from penetrating injuries. Miscellanea, personal series, clinical and CT findings
International Nuclear Information System (INIS)
Penetrating liver wounds are related to many causes and rank second after blunt abdominal and liver trauma. In this report are examined the clinical and radiological findings of personal series of patients with penetrating trauma, especially by firearms and stab and cut wounds. It will also tried to define the diagnostic workup of these traumas, which is especially based on CT signs of liver damage and associated changes and which is of basic importance for following treatment, both surgical or conservative. In the last seven years it was retrospectively reviewed 31 cases of penetrating liver trauma. The patients were 19 men and 12 women, ranging in age 18 to 73 (mean 42), with penetrating liver injuries from firearms (16 patients) and stab (9 cases) wounds; 6 patients had injuries from different cases. Abdominal CT was carried out in emergency with the CT Angiography (CTA) technique in all patients. In the patients with suspected chest and abdomen involvement CT ...
2000-12-01
Aortic non communicating dissections. A study with helical CT
International Nuclear Information System (INIS)
The evaluate the signs of aortic intramural hematoma with helical CT and the diagnostic role of this technique in patients with this condition. It was reviewed the CT findings of 396 patients submitted to emergency examinations for suspected aortic dissection from 1995 to 1999. Only 18 patients (6 women and 12 men) had CT signs of aortic intramural hematoma. Helical CT studies were carried out with the following parameters: slice thickness 10 mm, reconstruction index 10, feed 1.5 mm, conventional algorithm with minimum values of 130 kV and 125mA. All patients were examined with dynamic contrast-enhanced CT, before and after a power injection of 130 mL ionic contrast material. It was studied: hematoma localization and longitudinal extension; thickness and density of aortic wall; presence and location of intimal calcifications; integrity of intimal wall; hemo mediastinum and/or hemo thorax. Aortic wall thickening appeared as a high density crescent-shaped area at baseline CT and had low ...
2000-09-01
Energy Technology Data Exchange (ETDEWEB)
Poly-Lactic-Acid (PLA) was evaluated for coating of vascular endoprotheses in the treatment of experimental arterio-venous-fistulae (AVF). Bilateral carotid-external jugular AVF were created in 5 adult dogs. 7 PLA coated nitinol stents were placed via a transfemoral approach covering 5 AVF. The contralateral AVF remained untreated. Angiography was performed immediately after stent placement, at weeks 1 and 3 and at months 3, 6 and 9. All grafts were removed and underwent histologic examination. In 2 cases the occlusion of the AVF was successful, while misplacement occurred in 3 cases. Occlusion of the parent vessel was disclosed in 3 cases. Histologic examination revealed a mild inflammatory reaction with the presence of macrophages. There was no foreign-body reaction or fragmentation of the arterial vessel wall. PLA, which is a well-known biodegradable material, showed a good mid-term biocompatibility. Elastic mismatch of the non-elastic coating and the ...
2001-02-01
Energy Technology Data Exchange (ETDEWEB)
NO{sub x} compounds, specifically NO and NO{sub 2}, are pollutants and potent greenhouse gases. Compact and inexpensive NO{sub x} sensors are necessary in the next generation of diesel (CIDI) automobiles to meet government emission requirements and enable the more rapid introduction of more efficient, higher fuel economy CIDI vehicles. Because the need for a NO{sub x} sensor is recent and the performance requirements are extremely challenging, most are still in the development phase. Currently, there is only one type of NO{sub x} sensor that is sold commercially, and it seems unlikely to meet more stringent future emission requirements. Automotive exhaust sensor development has focused on solid-state electrochemical technology, which has proven to be robust for in-situ operation in harsh, high-temperature environments (e.g., the oxygen stoichiometric sensor). Solid-state sensors typically rely on yttria-stabilized zirconia (YSZ) as the oxygen-ion conducting electrolyte and then target ...
2010-11-01
Flow Vaporization of CO{sub 2} in Microchannel Tubes
Energy Technology Data Exchange (ETDEWEB)
Carbon dioxide is receiving renewed interest as an efficient and environmentally safe refrigerant in a number of applications, including mobile air conditioning and heat pump systems, and hot water heat pumps. Compact heat exchangers for CO{sub 2} systems are designed with small-diameter tubing. The purpose of this study is therefore to provide a better basis for understanding and predicting heat transfer and pressure drop during flow vaporization of CO{sub 2} in microchannels. The ''unusual'' properties of carbon dioxide give heat transfer and two-phase flow characteristics that are very different from those of conventional refrigerants. Examples of these differences are the much higher pressure, the resulting high vapour density, a very low surface tension, and a low liquid viscosity. High pressure and low surface tension has a major effect on nucleate boiling characteristics, and earlier test data have shown a clear dominance of nucleate boiling ...
2002-07-01
Energy Technology Data Exchange (ETDEWEB)
Nuclear medicine and magnetic resonance imaging (MRI) are widely used in cardiac diagnostics. Both techniques have been carefully evaluated and are equivalent for the assessment of regional and global wall motion as well as the evaluation of ejection fraction and cardiac volumes, though MRI is herein currently seen as gold standard. For evaluation of myocardial perfusion, extensive data exist for nuclear imaging, that, next to high diagnostic accuracy for evaluation of coronary artery disease, show incremental prognostic information and allow for independent risk stratification. Because of rapid technical advance, myocardial perfusion imaging has also become feasible with cardiac MRI. Results of recent studies are promising, but the data are few compared to perfusion scintigraphy. For viability assessment in patients with ischemic cardiomyopathy, positron emission tomography (PET) with FDG is currently seen as gold standard. However, single photon emission computed tomography (SPECT) ...
2003-12-01
Energy Technology Data Exchange (ETDEWEB)
CT is a valuable tool in assessing thoracic gunshot wounds. CT is also the method of choice in emergency, because it permits rapid depiction of bullet damage to the chest and to other body districts. This in turn permits correct assessment of the main thoracic injuries, plus adequate and prompt planning of surgical treatment or support intensive care. It is reported on the role of CT in diagnosing the complex pleuropulmonary, cardiovascular and thoracic wall injuries caused by gunshot wounds, with their specific and acute signs which differ greatly fro those of other types of chest trauma. In the last 4 years, it was observed an amount of 76 cases of gunshot injury, twenty-six of them involved the chest. The patients, 25 men and 1 woman (mean age: 32 years, range: 17-48), were all submitted to emergency CT with iv contrast agent injection and the CT-angiography technique. The reanimator was always presented to monitor the patients' vital functions and ...
1999-11-01
Energy Technology Data Exchange (ETDEWEB)
Penetrating liver wounds are related to many causes and rank second after blunt abdominal and liver trauma. In this report are examined the clinical and radiological findings of personal series of patients with penetrating trauma, especially by firearms and stab and cut wounds. It will also tried to define the diagnostic workup of these traumas, which is especially based on CT signs of liver damage and associated changes and which is of basic importance for following treatment, both surgical or conservative. In the last seven years it was retrospectively reviewed 31 cases of penetrating liver trauma. The patients were 19 men and 12 women, ranging in age 18 to 73 (mean 42), with penetrating liver injuries from firearms (16 patients) and stab (9 cases) wounds; 6 patients had injuries from different cases. Abdominal CT was carried out in emergency with the CT Angiography (CTA) technique in all patients. In the patients with suspected chest and abdomen involvement CT ...
2000-12-01
40th Anniversary of the First Proton-Proton Collisions in the CERN Intersecting Storage Rings (ISR)
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