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Research and development program, fiscal year 1966

Description: The biomedical program of the Laboratory of Nuclear Medicine and Radiation Biology for FY 1966 is conducted within the scope of the following categories: Somatic Effects of Radiation; Combating Detrimental Effects of Radiation; Molecular and Cellular Level Studies; Environmental Radiation Studies; Radiological and Health Physics and Instrumentation; Chemical Toxicity; Cancer Research; and Selected Beneficial Applications. The overall objectives of the Laboratory within these areas of the Biology and Medicine program may be summarized as follows: (1) investigation of the effects of ionizing radiation on living organisms and systems of biological significance; (2) investigation of the dynamic aspects of physiological and biochemical processes in man, animals and plants and how these processes are modified by radiation and related pathological states; (3) the assessment and study of the immediate and long term consequences of the operation or detonation of nuclear devices on the fauna, and flora in man's environment and on man; (4) the development of methods of minimizing or preventing the detrimental effects of ionizing radiation; (5) research in, and development of, beneficial uses of ionizing radiation and radioactive substances in medicine and biology; (6) research in the development of new and more efficient radiation detection devices; (7) research, including field studies, as mutually agreed upon by the Commission and the University, in connection with the conduct of weapon tests and biomedical and civil effects experiments at such tests conducted at continental and overseas test sites; and (8) the conduct of training and educational activities in the biological and medical aspects of radiation and related fields.
Date: April 1, 1964
Partner: UNT Libraries Government Documents Department

Use of total beta counts to estimate GI tract dose rates

Description: It was the practice for several years to estimate the potential dose rate to the gastrointestinal from sanitary water sources by evaluating the results of radiochemical analysis of individual nuclides. The proposed method estimates the GI tract dose from Pasco and Richland domestic water from measurements of the total beta activity, and permits more frequent and more economical evaluation of a variable source of radiation exposure. Beginning with 1964 data, the GI tract dose rate for Richland and Pasco sanitary water has been obtained by multiplying the total beta count by a conversion factor derived from the historical relationship between the radiochemical analyses and the total beta counts. Either the accumulation of more data or changes in the relative abundance of the more significant nuclides in the water may result in changes in this factor.
Date: October 25, 1965
Creator: Hall, R.B.
Partner: UNT Libraries Government Documents Department

Research and development program, fiscal year 1970

Description: The biomedical program of the Laboratory of Nuclear Medicine and Radiation Biology for FY 1970 is conducted within the scope of the following categories: Somatic Effects of Radiation; Combating Detrimental Effects of Radiation; Molecular and Cellular Level Studies; Environmental Radiation Studies; Radiological and Health Physics and Instrumentation; Cancer Research; and Selected Beneficial Applications. The overall objectives of the Laboratory within these areas of the Biology and Medicine Program may be summarized as follows: (1) investigation of the effects of ionizing radiation on systems of biological significance and on living organisms; (2) assessment and study of the immediate and long term consequences of the environmental radioactivity on flora, fauna, and man; (3) development of beneficial uses of ionizing radiation and radioactive substances in medicine and biology; and (4) the conduct of training and educational activities in fields related to the biological and medical aspects of radiation.
Date: April 1, 1968
Partner: UNT Libraries Government Documents Department

Ecological Studies of the Hudson River Near Indian Point

Description: "The general purpose of [this study is] to determine the ecological responses of the [Hudson] River to various classes of potential pollutants, so that the discharge of waste heat and radionuclides from the Indian Point Power Plant can be evaluated in context with these" (p. 1).
Date: April 1971
Creator: New York University. Medical Center. Institute of Environmental Medicine.
Partner: UNT Libraries

Research and development program, fiscal year 1974

Description: The biomedical program of the Laboratory of Nuclear Medicine and Radiation Biology for Fiscal Year 1974 is conducted within the scope of the following categories: Effects of Radiation of Living Organisms; Molecular and Cellular Radiobiology; Land and Fresh Water Environmental Sciences; Radiological and Health Physics and Instrumentation; and Nuclear Medical Research. (ACR)
Date: April 1, 1972
Partner: UNT Libraries Government Documents Department

Radioecological Studies of the Hudson River

Description: "This report summarizes the results of the Hudson River radioecological studies conducted in 1973" (p. 1). The study investigates the behavior of gamma-emitting radionuclides in the Hudson River and the accumulation of natural alpha-emitting radionuclides.
Date: 1973
Creator: New York University. Medical Center. Institute of Environmental Medicine.
Partner: UNT Libraries

Acquisition, processing and display of gated cardiac scintigrams

Description: An improved method for non-traumatic and essentially noninvasive evaluation of left ventricular (LV) function with /sup 99m/Tc as the tracer was developed. This method combines previously used EKG gating techniques for cardiac blood pool visualization with new computerized acquisition, processing and display techniques. An Anger camera, a small computer, and a physiological synchronizer are used to acquire a sequence of eight scintigrams which span the entire cardiac cycle. Under our present protocol two twenty-minute sequences are obtained, one an LAO (50$sup 0$) projection, the other an RAO (30$sup 0$) projection. Subsequently these images are processed on-line with a digital filter to increase definition of the cardiac borders. The eight images are then displayed sequentially on a specially designed electronic monitor to give an impression of the beating heart somewhat analogous to that obtained with invasive contrast angiography. (auth)
Date: January 1, 1974
Creator: Alpert, N. M.; Chesler, D. A.; McKusick, K. A.; Potsaid, M. S.; Pohost, G. M. & Dinsmore, R. A.
Partner: UNT Libraries Government Documents Department

Biologic considerations in anatomic imaging with radionuclides. Final progress report, July 1974--June 1975

Description: An important task relating to anatomic imaging with radionuclides is the determination of factors which effect the use of imaging procedures. This is important to reduce radiation exposure in the population, to improve the efficacy of diagnostic imaging procedures and finally to provide a basis for evaluating the potential effects of proposed regulation of use rates. In this report we describe a methodology for obtaining clinical data relating to the use of the brain scan in an inner city teaching hospital. The development of a questionnaire suitable for use in a clinical setting and providing both prospective and retrospective data is presented. The results of the use of the questionnaire at the Johns Hopkins Hospital during a three month period in 1974 are shown and discussed. Some preliminary results from these data are given and a method for further analysis is indicated. (auth)
Date: January 1, 1975
Creator: Potchen, E. J.
Partner: UNT Libraries Government Documents Department

Clinical $sup 13$CO$sub 2$ breath tests: methodology and limitations

Description: Methods were developed to perform $sup 13$CO$sub 2$ breath tests and the limitations and sources of error in these tests were explored. The random error introduced during each step of the analysis was determined and it was found that the precision was limited by the fluctuations in the isotope ratio of the patient's endogenous CO$sub 2$. The detection limit was a 1.4 percent increase in the isotope ratio. This corresponds to an oxidation rate of 140 nmoles/kg-hr of singly labeled substrate to CO$sub 2$. The use of stable isotope $sup 13$C provides a safe and sensitive alternative to the use of the radionuclide $sup 14$C and extends the utility of CO$sub 2$ breath tests to the previously exempted populations of children and pregnant women. (auth)
Date: January 1, 1975
Creator: Schoeller, D.A.; Klein, P.D.; Schneider, J.F.; Solomons, N.W. & Watkins, J.B.
Partner: UNT Libraries Government Documents Department

Reconstruction tomography from incomplete projections

Description: In some instances, reconstruction radionuclide tomography must be carried out from projections that do not include projection values for all portions of the object to be reconstructed. This may occur, for example, when the field of view of the detector is limited, or when an opaque foreign body is present within the object. The effects of such incomplete projections upon reconstructions of computer-simulated phantoms were studied, using iterative and convolution methods. Several methods for reducing the resulting artifacts and inaccuracies are discussed. (auth)
Date: January 1, 1975
Creator: Oppenheim, B.E.
Partner: UNT Libraries Government Documents Department

Axial tomography and three dimensional image reconstruction

Description: A number of existing $gamma$ cameras for imaging of radioisotope distributions give depth information about the distribution. These devices have in common that they provide tomographic images of the object, that is, that images of a given object plane have that plane in focus and all other object planes contribute an out-of-focus background superimposed on the in-focus image. A method is described for three dimensional reconstruction of these axial tomographic images which removes the blurred off-plane activity from a number of transverse planes simultaneously. The method is applicable to a number of tomographic cameras, such as the multiple single-pinhole camera, the rotating slanted-hole collimator, the Anger focussing tomographic scanner, and the positron camera. The method can be implemented on a small computer having a disc system. (auth)
Date: November 1, 1975
Creator: Chang, L.T.; Macdonald, B. & Perez-Mendez, V.
Partner: UNT Libraries Government Documents Department

Cerebral imaging using $sup 68$Ga DTPA and the U.C.S.F. multiwire proportional chamber positron camera

Description: A multiwire proportional chamber positron camera consisting of four 48 x 48 cm$sup 2$ detectors linked to a small digital computer has been designed, constructed, and characterized. Initial clinical application to brain imaging using $sup 68$Ga DTPA in 10 patients with brain tumors is described. Tomographic image reconstruction is accomplished by an algorithm determining the intersection of the annihilation photon paths in planes of interest. Final image processing utilizes uniformity correction, simple thresholding, and smoothing. The positron brain images were compared to conventional scintillation brain scans and x-ray computerized axial tomograms (CAT) in each case. The positron studies have shown significant mitigation of confusing superficial activity resulting from craniotomy in comparison to conventional brain scans. Central necrosis of lesions observed in the positron images, but not in the conventional scans, has been confirmed in CAT. Modifications of the camera are being implemented to improve image quality, and these changes combined with the tomography inherent in the positron scans are anticipated to result in images superior in information content to conventional brain scans. (auth)
Date: December 1, 1975
Creator: Hattner, R.S.; Lim, C.B.; Swann, S.J.; Kaufman, L.; Perez-Mendez, V.; Chu, D. et al.
Partner: UNT Libraries Government Documents Department

14'' x 17'' film recorder for computer-enhanced scans

Description: Physician acceptance of computer-enhanced radionuclide scan results, presented in the form of small Polaroid pictures, has been very limited for a number of subjective reasons. A new recorder was designed and constructed that presents the results of computer augmented scans through a medium that is quite familiar to doctors, the standard 14 in. x 17 in. x-ray film. (auth)
Date: January 1, 1976
Creator: Morris, A. C., Jr.; Barclay, T. R.; Akin, T. E.; Hansard, M. C.; Gibbs, W. D. & Modzelewski, C. U.
Partner: UNT Libraries Government Documents Department

Comparison of positron tomography and scintigraphy with $sup 201$Tl for delineation of the myocardium

Description: Recent advances in nuclear medicine instrumentation have led to the development of improved positron-imaging systems which exceed in performance the earlier systems which were limited mainly by low count rate capability. This has led to renewed interest in positron imaging in general, primarily because such devices offer better resolution and higher sensitivity than conventional, mechanically collimated gamma cameras, as well as tomographic capability which may provide additional and more accurate information for the clinician. Furthermore, the unique capabilities of positrons for use in reconstructive imaging are beginning to be exploited. In the present report, results are presented from a preliminary study in which longitudinal tomographic myocardial images, produced with $sup 81$Rb as the positron-emitting label using the double camera coincidence system are compared with conventional myocardial images obtained with $sup 201$Tl and a gamma camera. (auth)
Date: January 1, 1976
Creator: Fill, H.; Buchin, M.; Harper, P.V.; Muehllehner, G.; Walsh, W.; Resnekov, L. et al.
Partner: UNT Libraries Government Documents Department

Early progress of the Biomedical Computing Technology Information Center (BCTIC)

Description: Through five years of effort by the Society of Nuclear Medicine Computer Committee, the Biomedical Computing Technology Information Center (BCTIC) was established by the Division of Biomedical and Environmental Research (DBER) of the U. S. Energy Research and Development Administration (ERDA) at the Oak Ridge National Laboratory in July of 1975. BCTIC forged ahead into the tasks of designing guidelines and procedures, acquisition and packaging of computer codes, data, and interface designs; building a bibliographic data base; and maintaining a directory of the user community. Important contacts were made with societies and individuals involved in biomedical computing; and BCTIC was publicized through news releases, the BCTIC newsletter (bimonthly, since October, 1975), presentations at meetings, and personal contacts. This paper presents the response BCTIC has received in its initial months, gives a progress report on the developmental phase, and takes a look to the future of BCTIC as a national technology resource in nuclear medicine computing. (auth)
Date: January 1, 1976
Creator: Maskewitz, B.F.; Henne, R.L. & McClain, W.J.
Partner: UNT Libraries Government Documents Department

Modification of radiation hazards to the adult and its fetus from nuclear medicine procedures

Description: The effects of perchlorate on the quantitative distribution patterns of / sup 99m/Tc intravenously administered as pertechnetate in the human adult and its fetus were studied in a variety of situations and are summarized. Perchlorate, when administered shortly before /sup 99m/Tc, suppresses concentration in the adult thyroid gland, stomach, and urine; but tends to increase intestinal localization; and prolongs disappearance from the blood. It also inhibits concentration in the placenta and fetus. The greatest reductions in fetal concentrations occur in the femur, spleen, stomach, and thyroid. The estimated radiation absorbed doses to the human fetus are about 80 mrad/mCi for /sup 99m/Tc- pertechnetate alone, and around 30 mrad/mCi if pretreatment with perchlorate is used. Previously localized /sup 99m/Tc may be released by perchlorate from the thyroid gland and stomach, but not from the placenta and fetus. (auth)
Date: January 1, 1976
Creator: Lathrop, K.A.
Partner: UNT Libraries Government Documents Department

Non-linear image processing

Description: Processing of nuclear medicine images is generally performed by essentially linear methods with the non-negativity condition being applied as the only non-linear process. The various methods used: matrix methods in signal space and Fourier or Hadamard transforms in frequency or sequency space are essentially equivalent. Further improvement in images can be obtained by the use of inherently non-linear methods. The recent development of an approximation to a least-difference method (as opposed to a least-square method) has led to an appreciation of the effects of data bounding and to the development of a more powerful process. Data bounding (modification of statistically improbable data values) is an inherently non-linear method with considerable promise. Strong bounding depending on two-dimensional least-squares fitting yields a reduction of mottling (buttermilk effect) not attainable with linear processes. A pre- bounding process removing very bad points is used to protect the strong bounding process from incorrectly modifying data points due to the weight of an extreme but yet unbounded point as the fitting area approaches it. (auth)
Date: January 1, 1976
Creator: Bell, P.R.; Dillon, R.S. & Bell, M.R.
Partner: UNT Libraries Government Documents Department

Nuclear medicine at Brookhaven National Laboratory

Description: The Nuclear Medicine Program at the Brookhaven National Laboratory seeks to develop new materials and methods for the investigation of human physiology and disease processes. Some aspects of this research are related to basic research of how radiopharmaceuticals work. Other aspects are directed toward direct applications as diagnostic agents. It is likely that cyclotron-produced positron emitting nuclides will assume greater importance in the next few years. This can be attributed to the ability to label biologically important molecules with high specific activity without affecting biological activity, using /sup 11/C, /sup 13/N, and /sup 15/O. Large quantities of these short-lived nuclides can be administered without excessive radiation dose and newer instrumentation will permit reconstructive axial tomography, providing truly quantitative display of distribution of radioactivity. The /sup 122/Xe-/sup 122/I generator has the potential for looking at rapid dynamic processes. Another generator, the /sup 68/Ge-/sup 68/Ga generator produces a positron emitter for the use of those far removed from cyclotrons. The possibilities for /sup 68/Ga radiopharmaceuticals are as numerous as those for /sup 99m/Tc diagnostic agents.
Date: January 1, 1976
Creator: Atkins, H.L.
Partner: UNT Libraries Government Documents Department

Characteristics of computed tomographic reconstruction noise and their effect on detectability

Description: The EMI 5005 scanner produces images with noise characteristics similar to those in simulated CT reconstructions. A detectability phantom is described which will provide a means of investigation of the effect on human detection capability of the peculiar correlations present in the noise present in CT scanner images.
Date: January 1, 1977
Creator: Hanson, K.M. & Boyd, D.P.
Partner: UNT Libraries Government Documents Department