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CT imaging of small animals using monochromatized synchrotron x rays

Description: Rats and chicken embryos were imaged in vivo with a prototype Multiple Energy Computed Tomography (MECT) system using monochromatized x rays from the X17 superconducting wiggler at the National Synchrotron Light Source. The CT configuration coated of a horizontal low-divergence, fan-shaped beam, 70 mm wide and 0.5 mm high, and a subject rotating about a vertical aids. A linear-array high-purity Ge detector with 140 elements, each 0.5 mm wide and 6 mm thick, was used with a data acquisition system that provides a linear response over almost six orders of magnitude of detector current. The dual photon absorptiometry (DPA) algorithm was applied to images of the rat head acquired at 20 and 45 keV to obtain two new images, one representing the low-Z, and the other the intermediate-Z clement group. The results indicate that the contrast resolution and the quantification accuracy of the images improve stepwise; first, with the monochromatic beam and, second, the DPA method. The system is a prototype for a brain scanner.
Date: January 1, 1992
Creator: Dilmanian, F.A.; Rarback, H.; Nachaliel, E.; Rivers, M.; Thomlinson, W.C.; Chapman, L.D. et al.
Partner: UNT Libraries Government Documents Department

Computed tomography using synchrotron radiation

Description: X-ray computed tomography (CT) is a widely used method of obtaining cross-sectional views of objects. The high intensity, natural collimation, monochromaticity and energy tunability of synchrotron x-ray sources could potentially be used to provide CT images of improved quality. The advantages of these systems would be that images could be produced more rapidly with better spatial resolution and reduced beam artifacts. In addition, images, in some cases, could be acquired with elemental sensitivity. As a demonstration of the capability of such a system, CT images were obtained of four slices of an excised pig heart in which the arteries and the cardiac chambers were filled with an iodinated medium. Images were taken with incident x-rays tuned successively to energies just above and below the iodine K edge. Iodine specific images were obtained by logarithmically subtracting the low energy image data from the high energy data and then reconstructing the image. CT imaging using synchrotron radiation may become a convenient and non-destructive method of imaging samples difficult to study by other methods.
Date: September 1, 1983
Creator: Thompson, A.C.; Llacer, J.; Finman, L.C.; Hughes, E.B.; Otis, J.N.; Wilson, S. et al.
Partner: UNT Libraries Government Documents Department

The development of a Compton lung densitometer

Description: A field instrument is being developed for the non-invasive determination of absolute lung density using unique Compton backscattering techniques. A system consisting of a monoenergetic gamma-ray beam and a shielded high resolution high-purity-germanium (HPGe) detector in a close-coupled geometry is designed to minimize errors due to multiple scattering and uncontrollable attenuation in the chestwall. Results of studies on system performance with phantoms, the optimization of detectors, and the fabrication of a practical gamma-ray source are presented. 3 refs., 6 figs., 2 tabs.
Date: November 1, 1988
Creator: Loo, B.W.; Goulding, F.S.; Madden, N.W. & Simon, D.S.
Partner: UNT Libraries Government Documents Department

Applications of nuclear techniques for in vivo body composition studies at Brookhaven National Laboratory

Description: A series of technical developments and their clinical applications in various nuclear technologies at Brookhaven National Laboratory is described. These include the development of a portable neutron activation facility for measuring cadmium in vivo in kidney and liver, a technique for the measurement of body iron utilizing nuclear resonant scattering of gamma rays, a non-invasive measure of the skeletal levels of lead by an x-ray fluorescence technique, and the development of a pulsed Van de Graaff generator as a source of pulsed neutrons for the measurement of lung silicon. (ACR)
Date: January 1, 1981
Creator: Cohn, S.H.; Ellis, K.J.; Vartsky, D.; Vaswani, A.N. & Wielopolski, L.
Partner: UNT Libraries Government Documents Department

Power Burst Facility/Boron Neutron Capture Therapy Program for cancer treatment

Description: This bulletin discusses activities during this reporting period in the areas of: supporting technology development; large animal model studies; melanoma project; human studies; stability, pharmacology, and toxicology of drugs; and PBF technical support. (FL)
Date: October 1, 1990
Creator: Ackermann, A.L. (ed.)
Partner: UNT Libraries Government Documents Department

Myocardial uptake of cocaine and effects of cocaine on myocardial substrate utilization and perfusion in hypertensive rats

Description: Cocaine abuse is a problem causing world-wide concern and the number of deaths following cocaine use is increasing. Cardiovascular complications following cocaine include severe tachyarrythmias, pulmonary edema, myocardial infarction, and acute renal failure, which are major problems confronting emergency facilities. While the studies of cocaine effects on the brain have been given the most attention, it is clear that the effects of cocaine on the cardiovascular system are of great importance, given the increasing number of reports on sudden death and myocardial infarctions in young adults related to cocaine use. The precise mechanisms of cardiotoxic actions of cocaine are unclear. We investigated the whole-body distribution of C-14-labeled cocaine to determine the cocaine-binding sites, including blocking experiments to determine the nature of regional binding sites, and differential response of the normal vs. diseased heart (hypertensive cardiomyopathy) in an animal model to mimic a potentially high risk population. We investigated the acute effects of cocaine on myocardial metabolism using two myocardial energy substrate analogs, fatty acid and glucose with comparison with regional perfusion.
Date: January 1, 1992
Creator: Som, P.; Wang, G.J. (Brookhaven National Lab., Upton, NY (United States)); Oster, Z.H. (State Univ. of New York, Stony Brook, NY (United States)); Knapp, F.F. Jr. (Oak Ridge National Lab., TN (United States)); Yonekura, Y. (Kyoto Univ. (Japan). Faculty of Medicine); Fujibayashi, Y. (Kyoto Univ. (Japan). Hospital) et al.
Partner: UNT Libraries Government Documents Department

New cholescintigraphic agent: ruthenium-97-DISIDA

Description: These studies demonstrate the first application of Ru-97-DISIDA in human subjects. High quality images were obtained. Scintigraphic findings in patients with hepatobiliary disorders were consistent with the biodistribution data obtained in experinmental animals and with other imaging procedures and clinical findings. Administration of Ru-97-DISIDA I.V. and of a solid test meal labeled with Tc-99m-Sulfur Colloid allowed simulateneous detection and quantification of deodenogastric reflux and determination of the gastric emptying rate. This represents an advantage as compared to the currently used techniques which necessitate two separate studies if a solid meal is used, or would mandate a liquid meal for a simultaneous study. The excellent nuclear decay characteristics of Ru-97 (tl/2 69.6 h, gamma 216 keV, 86%, no betas) permit delayed study of the hepatobiliary system with considerably less radiation exposure than I-131 Rose Bengal and with a marked improvement in image quality. 5 refs., 3 figs., 3 tabs.
Date: June 1, 1986
Creator: Zanzi, I.; Srivastava, S.C.; Meinken, G,E.; Robeson, W.; Mausner, L.F.; Fairchild, R.G. et al.
Partner: UNT Libraries Government Documents Department

Use of nuclear resonant scattering of gamma rays for in vivo measurement of iron

Description: A technique for determination of elements in human body in-vivo, utilizing nuclear resonant scattering of gamma rays has been developed. 847 keV photons emitted from a gaseous /sup 56/MnCl/sub 2/ source are resonantly scattered from /sup 56/Fe present in the body. The detection of these gamma rays is used to estimate the iron content of the liver or heart of patients. Details of the calibration procedure and potential molecular effects are described.
Date: January 1, 1981
Creator: Vartsky, D.; Wielopolski, L.; Ellis, K.J. & Cohn, S.H.
Partner: UNT Libraries Government Documents Department

Positron emission tomographic imaging of tumors using monoclonal antibodies

Description: This research project is developing methods for utilizing positron emission tomography (PET) to increase the clinical potential of radiolabeled monoclonal antibodies (MAbs). This report describes the development of methods for labeling MAbs and their fragments with positron-emitting halogen nuclides, fluorine-18 and iodine-124. These nulides were selected because of the widespread availability of F-18 and because of our extensive experience in the development of new protein radiohalogenation methods.
Date: August 1, 1992
Creator: Zalutsky, M.R.
Partner: UNT Libraries Government Documents Department

New techniques for positron emission tomography in the study of human neurological disorders

Description: This progress report describes accomplishments of four programs. The four programs are entitled (1) Faster,simpler processing of positron-computing precursors: New physicochemical approaches, (2) Novel solid phase reagents and methods to improve radiosynthesis and isotope production, (3) Quantitative evaluation of the extraction of information from PET images, and (4) Optimization of tracer kinetic methods for radioligand studies in PET.
Date: January 1, 1993
Creator: Kuhl, D.E.
Partner: UNT Libraries Government Documents Department