Nuclear Medicine: A specialty field of radiology concerned with diagnostic, therapeutic, and investigative use of radioactive compounds in a pharmaceutical form.Nuclear Medicine Department, Hospital: Hospital department responsible for the administration and management of nuclear medicine services.Technology, Radiologic: The application of scientific knowledge or technology to the field of radiology. The applications center mostly around x-ray or radioisotopes for diagnostic and therapeutic purposes but the technological applications of any radiation or radiologic procedure is within the scope of radiologic technology.Radionuclide Imaging: The production of an image obtained by cameras that detect the radioactive emissions of an injected radionuclide as it has distributed differentially throughout tissues in the body. The image obtained from a moving detector is called a scan, while the image obtained from a stationary camera device is called a scintiphotograph.Radiopharmaceuticals: Compounds that are used in medicine as sources of radiation for radiotherapy and for diagnostic purposes. They have numerous uses in research and industry. (Martindale, The Extra Pharmacopoeia, 30th ed, p1161)Radiation ProtectionRadiation Dosage: The amount of radiation energy that is deposited in a unit mass of material, such as tissues of plants or animal. In RADIOTHERAPY, radiation dosage is expressed in gray units (Gy). In RADIOLOGIC HEALTH, the dosage is expressed by the product of absorbed dose (Gy) and quality factor (a function of linear energy transfer), and is called radiation dose equivalent in sievert units (Sv).Radiation Monitoring: The observation, either continuously or at intervals, of the levels of radiation in a given area, generally for the purpose of assuring that they have not exceeded prescribed amounts or, in case of radiation already present in the area, assuring that the levels have returned to those meeting acceptable safety standards.Tomography, Emission-Computed, Single-Photon: A method of computed tomography that uses radionuclides which emit a single photon of a given energy. The camera is rotated 180 or 360 degrees around the patient to capture images at multiple positions along the arc. The computer is then used to reconstruct the transaxial, sagittal, and coronal images from the 3-dimensional distribution of radionuclides in the organ. The advantages of SPECT are that it can be used to observe biochemical and physiological processes as well as size and volume of the organ. The disadvantage is that, unlike positron-emission tomography where the positron-electron annihilation results in the emission of 2 photons at 180 degrees from each other, SPECT requires physical collimation to line up the photons, which results in the loss of many available photons and hence degrades the image.Radiometry: The measurement of radiation by photography, as in x-ray film and film badge, by Geiger-Mueller tube, and by SCINTILLATION COUNTING.Radioisotopes: Isotopes that exhibit radioactivity and undergo radioactive decay. (From Grant & Hackh's Chemical Dictionary, 5th ed & McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Radioactive Tracers: Radioactive substances added in minute amounts to the reacting elements or compounds in a chemical process and traced through the process by appropriate detection methods, e.g., Geiger counter. Compounds containing tracers are often said to be tagged or labeled. (Hawley's Condensed Chemical Dictionary, 12th ed)Positron-Emission Tomography: An imaging technique using compounds labelled with short-lived positron-emitting radionuclides (such as carbon-11, nitrogen-13, oxygen-15 and fluorine-18) to measure cell metabolism. It has been useful in study of soft tissues such as CANCER; CARDIOVASCULAR SYSTEM; and brain. SINGLE-PHOTON EMISSION-COMPUTED TOMOGRAPHY is closely related to positron emission tomography, but uses isotopes with longer half-lives and resolution is lower.Radioisotope Renography: Graphic tracing over a time period of radioactivity measured externally over the kidneys following intravenous injection of a radionuclide which is taken up and excreted by the kidneys.Diagnostic Imaging: Any visual display of structural or functional patterns of organs or tissues for diagnostic evaluation. It includes measuring physiologic and metabolic responses to physical and chemical stimuli, as well as ultramicroscopy.Technetium: The first artificially produced element and a radioactive fission product of URANIUM. Technetium has the atomic symbol Tc, atomic number 43, and atomic weight 98.91. All technetium isotopes are radioactive. Technetium 99m (m=metastable) which is the decay product of Molybdenum 99, has a half-life of about 6 hours and is used diagnostically as a radioactive imaging agent. Technetium 99 which is a decay product of technetium 99m, has a half-life of 210,000 years.Gamma Cameras: Electronic instruments that produce photographs or cathode-ray tube images of the gamma-ray emissions from organs containing radionuclide tracers.Health Physics: The science concerned with problems of radiation protection relevant to reducing or preventing radiation exposure, and the effects of ionizing radiation on humans and their environment.Hospitals, Satellite: Those hospitals which are extensions of a main hospital and are wholly or partly administered by that hospital.Technetium Tc 99m Mertiatide: A technetium diagnostic aid used in renal function determination.Medicine, Chinese Traditional: A system of traditional medicine which is based on the beliefs and practices of the Chinese culture.Radioactivity: The spontaneous transformation of a nuclide into one or more different nuclides, accompanied by either the emission of particles from the nucleus, nuclear capture or ejection of orbital electrons, or fission. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Sodium Pertechnetate Tc 99m: A gamma-emitting radionuclide imaging agent used for the diagnosis of diseases in many tissues, particularly in the gastrointestinal system, cardiovascular and cerebral circulation, brain, thyroid, and joints.Radionuclide Generators: Separation systems containing a relatively long-lived parent radionuclide which produces a short-lived daughter in its decay scheme. The daughter can be periodically extracted (milked) by means of an appropriate eluting agent.Hospital Departments: Major administrative divisions of the hospital.Allied Health Personnel: Health care workers specially trained and licensed to assist and support the work of health professionals. Often used synonymously with paramedical personnel, the term generally refers to all health care workers who perform tasks which must otherwise be performed by a physician or other health professional.Individualized Medicine: Therapeutic approach tailoring therapy for genetically defined subgroups of patients.Radiobiology: Study of the scientific principles, mechanisms, and effects of the interaction of ionizing radiation with living matter. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Centralized Hospital Services: The coordination of services in one area of a facility to improve efficiency.Pharmacy: The practice of compounding and dispensing medicinal preparations.Radiation Equipment and Supplies: Instruments and apparatus for radiation applications and their components and associated expendables.Body Burden: The total amount of a chemical, metal or radioactive substance present at any time after absorption in the body of man or animal.Tomography, Emission-Computed: Tomography using radioactive emissions from injected RADIONUCLIDES and computer ALGORITHMS to reconstruct an image.Technetium Compounds: Inorganic compounds that contain TECHNETIUM as an integral part of the molecule. Technetium 99m (m=metastable) is an isotope of technetium that has a half-life of about 6 hours. Technetium 99, which has a half-life of 210,000 years, is a decay product of technetium 99m.Internal Medicine: A medical specialty concerned with the diagnosis and treatment of diseases of the internal organ systems of adults.Radiology Information Systems: Information systems, usually computer-assisted, designed to store, manipulate, and retrieve information for planning, organizing, directing, and controlling administrative activities associated with the provision and utilization of radiology services and facilities.Scintillation Counting: Detection and counting of scintillations produced in a fluorescent material by ionizing radiation.Tin Fluorides: Inorganic fluorides of tin. They include both stannic fluoride (tin tetrafluoride) and stannous fluoride (tin difluoride). The latter is used in the prevention of dental caries.Medicine, Traditional: Systems of medicine based on cultural beliefs and practices handed down from generation to generation. The concept includes mystical and magical rituals (SPIRITUAL THERAPIES); PHYTOTHERAPY; and other treatments which may not be explained by modern medicine.Medicine, Kampo: System of herbal medicine practiced in Japan by both herbalists and practitioners of modern medicine. Kampo originated in China and is based on Chinese herbal medicine (MEDICINE, CHINESE TRADITIONAL).Radiology Department, Hospital: Hospital department which is responsible for the administration and provision of x-ray diagnostic and therapeutic services.Organotechnetium Compounds: Organic compounds that contain technetium as an integral part of the molecule. These compounds are often used as radionuclide imaging agents.Whole Body Imaging: The creation of a visual display of the inside of the entire body of a human or animal for the purposes of diagnostic evaluation. This is most commonly achieved by using MAGNETIC RESONANCE IMAGING; or POSITRON EMISSION TOMOGRAPHY.Radiology: A specialty concerned with the use of x-ray and other forms of radiant energy in the diagnosis and treatment of disease.Whole-Body Counting: Measurement of radioactivity in the entire human body.Iodine Radioisotopes: Unstable isotopes of iodine that decay or disintegrate emitting radiation. I atoms with atomic weights 117-139, except I 127, are radioactive iodine isotopes.Medicine: The art and science of studying, performing research on, preventing, diagnosing, and treating disease, as well as the maintenance of health.Purchasing, Hospital: Hospital department responsible for the purchasing of supplies and equipment.Tin Compounds: Inorganic compounds that contain tin as an integral part of the molecule.Fluorodeoxyglucose F18: The compound is given by intravenous injection to do POSITRON-EMISSION TOMOGRAPHY for the assessment of cerebral and myocardial glucose metabolism in various physiological or pathological states including stroke and myocardial ischemia. It is also employed for the detection of malignant tumors including those of the brain, liver, and thyroid gland. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1162)Oxyquinoline: An antiseptic with mild fungistatic, bacteriostatic, anthelmintic, and amebicidal action. It is also used as a reagent and metal chelator, as a carrier for radio-indium for diagnostic purposes, and its halogenated derivatives are used in addition as topical anti-infective agents and oral antiamebics.Societies, Medical: Societies whose membership is limited to physicians.Pentetic Acid: An iron chelating agent with properties like EDETIC ACID. DTPA has also been used as a chelator for other metals, such as plutonium.Gallium: A rare, metallic element designated by the symbol, Ga, atomic number 31, and atomic weight 69.72.Tomography, X-Ray Computed: Tomography using x-ray transmission and a computer algorithm to reconstruct the image.Diagnostic Techniques, Radioisotope: Any diagnostic evaluation using radioactive (unstable) isotopes. This diagnosis includes many nuclear medicine procedures as well as radioimmunoassay tests.Allied Health Occupations: Occupations of medical personnel who are not physicians, and are qualified by special training and, frequently, by licensure to work in supporting roles in the health care field. These occupations include, but are not limited to, medical technology, physical therapy, physician assistant, etc.Gallium Radioisotopes: Unstable isotopes of gallium that decay or disintegrate emitting radiation. Ga atoms with atomic weights 63-68, 70 and 72-76 are radioactive gallium isotopes.ComputersPhantoms, Imaging: Devices or objects in various imaging techniques used to visualize or enhance visualization by simulating conditions encountered in the procedure. Phantoms are used very often in procedures employing or measuring x-irradiation or radioactive material to evaluate performance. Phantoms often have properties similar to human tissue. Water demonstrates absorbing properties similar to normal tissue, hence water-filled phantoms are used to map radiation levels. Phantoms are used also as teaching aids to simulate real conditions with x-ray or ultrasonic machines. (From Iturralde, Dictionary and Handbook of Nuclear Medicine and Clinical Imaging, 1990)Technetium Tc 99m Medronate: A gamma-emitting radionuclide imaging agent used primarily in skeletal scintigraphy. Because of its absorption by a variety of tumors, it is useful for the detection of neoplasms.Teleradiology: The electronic transmission of radiological images from one location to another for the purposes of interpretation and/or consultation. Users in different locations may simultaneously view images with greater access to secondary consultations and improved continuing education. (From American College of Radiology, ACR Standard for Teleradiology, 1994, p3)Isotope Labeling: Techniques for labeling a substance with a stable or radioactive isotope. It is not used for articles involving labeled substances unless the methods of labeling are substantively discussed. Tracers that may be labeled include chemical substances, cells, or microorganisms.History of MedicineLaboratories: Facilities equipped to carry out investigative procedures.Clinical Medicine: The study and practice of medicine by direct examination of the patient.Education, Continuing: Educational programs designed to inform individuals of recent advances in their particular field of interest. They do not lead to any formal advanced standing.Technetium Tc 99m Dimercaptosuccinic Acid: A nontoxic radiopharmaceutical that is used in the diagnostic imaging of the renal cortex.Radiochemistry: The study of the chemical and physical phenomena of radioactive substances.Technetium Tc 99m Sestamibi: A technetium imaging agent used to reveal blood-starved cardiac tissue during a heart attack.Drugs, Chinese Herbal: Chinese herbal or plant extracts which are used as drugs to treat diseases or promote general well-being. The concept does not include synthesized compounds manufactured in China.Credentialing: The recognition of professional or technical competence through registration, certification, licensure, admission to association membership, the award of a diploma or degree, etc.Molecular Imaging: The use of molecularly targeted imaging probes to localize and/or monitor biochemical and cellular processes via various imaging modalities that include RADIONUCLIDE IMAGING; ULTRASONOGRAPHY; MAGNETIC RESONANCE IMAGING; FLUORESCENCE IMAGING; and MICROSCOPY.Sensitivity and Specificity: Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)Tantalum: Tantalum. A rare metallic element, atomic number 73, atomic weight 180.948, symbol Ta. It is a noncorrosive and malleable metal that has been used for plates or disks to replace cranial defects, for wire sutures, and for making prosthetic devices. (Dorland, 28th ed)3-Iodobenzylguanidine: A guanidine analog with specific affinity for tissues of the sympathetic nervous system and related tumors. The radiolabeled forms are used as antineoplastic agents and radioactive imaging agents. (Merck Index, 12th ed) MIBG serves as a neuron-blocking agent which has a strong affinity for, and retention in, the adrenal medulla and also inhibits ADP-ribosyltransferase.Regenerative Medicine: A field of medicine concerned with developing and using strategies aimed at repair or replacement of damaged, diseased, or metabolically deficient organs, tissues, and cells via TISSUE ENGINEERING; CELL TRANSPLANTATION; and ARTIFICIAL ORGANS and BIOARTIFICIAL ORGANS and tissues.Emergency Medicine: The branch of medicine concerned with the evaluation and initial treatment of urgent and emergent medical problems, such as those caused by accidents, trauma, sudden illness, poisoning, or disasters. Emergency medical care can be provided at the hospital or at sites outside the medical facility.Technetium Tc 99m Pyrophosphate: A radionuclide imaging agent used primarily in scintigraphy or tomography of the heart to evaluate the extent of the necrotic myocardial process. It has also been used in noninvasive tests for the distribution of organ involvement in different types of amyloidosis and for the evaluation of muscle necrosis in the extremities.Evidence-Based Medicine: An approach of practicing medicine with the goal to improve and evaluate patient care. It requires the judicious integration of best research evidence with the patient's values to make decisions about medical care. This method is to help physicians make proper diagnosis, devise best testing plan, choose best treatment and methods of disease prevention, as well as develop guidelines for large groups of patients with the same disease. (from JAMA 296 (9), 2006)Film Dosimetry: Use of a device (film badge) for measuring exposure of individuals to radiation. It is usually made of metal, plastic, or paper and loaded with one or more pieces of x-ray film.