Cumulative Radiation Exposure and Your Patient
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Personal Radiation Monitoring
Personal Radiation Monitoring Tim Finney 2020 Radiation monitoring Curtin staff and students who work with x-ray machines, neutron generators, or radioactive substances are monitored for exposure to ionising radiation. The objective of radiation monitoring is to ensure that existing safety procedures keep radiation exposure As Low As Reasonably Achievable (ALARA). Personal radiation monitoring badges Radiation exposure is measured using personal radiation monitoring badges. Badges contain a substance that registers how much radiation has been received. Here is the process by which a user’s radiation dose is measured: 1. The user is given a badge to wear 2. The user wears the badge for a set time period (usually three months) 3. At the end of the set time, the user returns the badge 4. The badge is sent away to be read 5. A dose report is issued. These steps are repeated until monitoring is no longer required. Badges are supplied by a personal radiation monitoring service provider. Curtin uses a service provider named Landauer. In addition to user badges, the service provider sends control badges that are kept on site in a safe place away from radiation sources. The service provider reads each badge using a process that extracts a signal from the substance contained in the badge to obtain a dose measurement. (Optically stimulated luminescence is one such process.) The dose received by the control badge is subtracted from the user badge reading to obtain the user dose during the monitoring period. Version 1.0 Uncontrolled document when printed Health and Safety Page 1 of 7 A personal radiation monitoring badge Important Radiation monitoring badges do not protect you from radiation exposure. -
Proper Use of Radiation Dose Metric Tracking for Patients Undergoing Medical Imaging Exams
Proper Use of Radiation Dose Metric Tracking for Patients Undergoing Medical Imaging Exams Frequently Asked Questions Introduction In August of 2021, the American Association of Physicists in Medicine (AAPM), the American College of Radiology (ACR), and the Health Physics Society (HPS) jointly released the following position statement advising against using information about a patient’s previous cumulative dose information from medical imaging exams to decide the appropriateness of future imaging exams. This statement was also endorsed by the Radiological Society of North America (RSNA). It is the position of the American Association of Physicists in Medicine (AAPM), the American College of Radiology (ACR), and the Health Physics Society (HPS) that the decision to perform a medical imaging exam should be based on clinical grounds, including the information available from prior imaging results, and not on the dose from prior imaging-related radiation exposures. AAPM has long advised, as recommended by the International Commission on Radiological Protection (ICRP), that justification of potential patient benefit and subsequent optimization of medical imaging exposures are the most appropriate actions to take to protect patients from unnecessary medical exposures. This is consistent with the foundational principles of radiation protection in medicine, namely that patient radiation dose limits are inappropriate for medical imaging exposures. Therefore, the AAPM recommends against using dose values, including effective dose, from a patient’s prior imaging exams for the purposes of medical decision making. Using quantities such as cumulative effective dose may, unintentionally or by institutional or regulatory policy, negatively impact medical decisions and patient care. This position statement applies to the use of metrics to longitudinally track a patient’s dose from medical radiation exposures and infer potential stochastic risk from them. -
Radiation Basics
Environmental Impact Statement for Remediation of Area IV \'- f Susana Field Laboratory .A . &at is radiation? Ra - -.. - -. - - . known as ionizing radiatios bScause it can produce charged.. particles (ions)..- in matter. .-- . 'I" . .. .. .. .- . - .- . -- . .-- - .. What is radioactivity? Radioactivity is produced by the process of radioactive atmi trying to become stable. Radiation is emitted in the process. In the United State! Radioactive radioactivity is measured in units of curies. Smaller fractions of the curie are the millicurie (111,000 curie), the microcurie (111,000,000 curie), and the picocurie (1/1,000,000 microcurie). Particle What is radioactive material? Radioactive material is any material containing unstable atoms that emit radiation. What are the four basic types of ionizing radiation? Aluminum Leadl Paper foil Concrete Adphaparticles-Alpha particles consist of two protons and two neutrons. They can travel only a few centimeters in air and can be stopped easily by a sheet of paper or by the skin's surface. Betaparticles-Beta articles are smaller and lighter than alpha particles and have the mass of a single electron. A high-energy beta particle can travel a few meters in the air. Beta particles can pass through a sheet of paper, but may be stopped by a thin sheet of aluminum foil or glass. Gamma rays-Gamma rays (and x-rays), unlike alpha or beta particles, are waves of pure energy. Gamma radiation is very penetrating and can travel several hundred feet in air. Gamma radiation requires a thick wall of concrete, lead, or steel to stop it. Neutrons-A neutron is an atomic particle that has about one-quarter the weight of an alpha particle. -
Radiation Safety in Fluoroscopy
Radiation Safety for New Medical Physics Graduate Students John Vetter, PhD Medical Physics Department UW School of Medicine & Public Health Background and Purpose of This Training . This is intended as a brief introduction to radiation safety from the perspective of a Medical Physicist. Have a healthy respect for radiation without an undue fear of it. The learning objectives are: . To point out the sources of ionizing radiation in everyday life and at work. To present an overview of the health effects of ionizing radiation. To show basic concepts and techniques used to protect against exposure to ionizing radiation. Further training in Radiation Safety can be found at: https://ehs.wisc.edu/radiation-safety-training/ Outline . Ionizing Radiation . Definition, Quantities & Units . Levels of Radiation Exposure . Background & Medical . Health Effects of Radiation Exposure . Stochastic & Deterministic . Limits on Radiation Exposure . Rationale for Exposure Limits . Minimizing Radiation Exposure . Time, Distance, Shielding, Containment Definition of Ionizing Radiation . Radiation can be thought of as energy in motion. Electromagnetic radiation is pure energy that moves at the speed of light in the form of photons and includes: radio waves; microwaves; infrared, visible and ultraviolet light; x-rays and γ-rays. A key difference between these forms of electromagnetic radiation is the amount of energy that each photon carries. Some ultraviolet light, and X-rays and Gamma-rays have enough energy to remove electrons from atoms as they are absorbed, forming positive and negatively charged ions. These forms of radiation are called ionizing radiation. Radio waves, microwaves, infrared and visible light do not have enough energy to ionize atoms. -
Cumulative Radiation Dose in Patients Admitted with Subarachnoid Hemorrhage: a Prospective PATIENT SAFETY Study Using a Self-Developing Film Badge
Cumulative Radiation Dose in Patients Admitted with Subarachnoid Hemorrhage: A Prospective PATIENT SAFETY Study Using a Self-Developing Film Badge A.C. Mamourian BACKGROUND AND PURPOSE: While considerable attention has been directed to reducing the x-ray H. Young dose of individual imaging studies, there is little information available on the cumulative dose during imaging-intensive hospitalizations. We used a radiation-sensitive badge on 12 patients admitted with M.F. Stiefel SAH to determine if this approach was feasible and to measure the extent of their x-ray exposure. MATERIALS AND METHODS: After obtaining informed consent, we assigned a badge to each of 12 patients and used it for all brain imaging studies during their ICU stay. Cumulative dose was deter- mined by quantifying exposure on the badge and correlating it with the number and type of examinations. RESULTS: The average skin dose for the 3 patients who had only diagnostic DSA without endovascular intervention was 0.4 Gy (0.2–0.6 Gy). The average skin dose of the 8 patients who had both diagnostic DSA and interventions (eg, intra-arterial treatment of vasospasm and coiling of aneurysms) was 0.9 Gy (1.8–0.4 Gy). One patient had only CT examinations. There was no effort made to include or exclude the badge in the working view during interventions. CONCLUSIONS: It is feasible to incorporate a film badge that uses a visual scale to monitor the x-ray dose into the care of hospitalized patients. Cumulative skin doses in excess of 1 Gy were not uncommon (3/12) in this group of patients with acute SAH. -
Radiation Glossary
Radiation Glossary Activity The rate of disintegration (transformation) or decay of radioactive material. The units of activity are Curie (Ci) and the Becquerel (Bq). Agreement State Any state with which the U.S. Nuclear Regulatory Commission has entered into an effective agreement under subsection 274b. of the Atomic Energy Act of 1954, as amended. Under the agreement, the state regulates the use of by-product, source, and small quantities of special nuclear material within said state. Airborne Radioactive Material Radioactive material dispersed in the air in the form of dusts, fumes, particulates, mists, vapors, or gases. ALARA Acronym for "As Low As Reasonably Achievable". Making every reasonable effort to maintain exposures to ionizing radiation as far below the dose limits as practical, consistent with the purpose for which the licensed activity is undertaken. It takes into account the state of technology, the economics of improvements in relation to state of technology, the economics of improvements in relation to benefits to the public health and safety, societal and socioeconomic considerations, and in relation to utilization of radioactive materials and licensed materials in the public interest. Alpha Particle A positively charged particle ejected spontaneously from the nuclei of some radioactive elements. It is identical to a helium nucleus, with a mass number of 4 and a charge of +2. Annual Limit on Intake (ALI) Annual intake of a given radionuclide by "Reference Man" which would result in either a committed effective dose equivalent of 5 rems or a committed dose equivalent of 50 rems to an organ or tissue. Attenuation The process by which radiation is reduced in intensity when passing through some material. -
``Low Dose``And/Or``High Dose``In Radiation Protection: a Need To
IAEA-CN-67/154 "LOW DOSE" AND/OR "HIGH DOSE" IN RADIATION PROTECTION: A NEED TO SETTING CRITERIA FOR DOSE CLASSIFICATION Mehdi Sohrabi National Radiation Protection Department & XA9745670 Center for Research on Elevated Natural Radiation Atomic Energy Organization of Iran, Tehran ABSTRACT The "low dose" and/or "high dose" of ionizing radiation are common terms widely used in radiation applications, radiation protection and radiobiology, and natural radiation environment. Reading the title, the papers of this interesting and highly important conference and the related literature, one can simply raise the question; "What are the levels and/or criteria for defining a low dose or a high dose of ionizing radiation?". This is due to the fact that the criteria for these terms and for dose levels between these two extreme quantities have not yet been set, so that the terms relatively lower doses or higher doses are usually applied. Therefore, setting criteria for classification of radiation doses in the above mentioned areas seems a vital need. The author while realizing the existing problems to achieve this important task, has made efforts in this paper to justify this need and has proposed some criteria, in particular for the classification of natural radiation areas, based on a system of dose limitation. In radiation applications, a "low dose" is commonly associated to applications delivering a dose such as given to a patient in a medical diagnosis and a "high dose" is referred to a dose in applications such as radiotherapy, mutation breeding, control of sprouting, control of insects, delay ripening, and sterilization having a range of doses from 1 to 105 Gy, for which the term "high dose dosimetry" is applied [1]. -
Internal and External Exposure Exposure Routes 2.1
Exposure Routes Internal and External Exposure Exposure Routes 2.1 External exposure Internal exposure Body surface From outer space contamination and the sun Inhalation Suspended matters Food and drink consumption From a radiation Lungs generator Radio‐ pharmaceuticals Wound Buildings Ground Radiation coming from outside the body Radiation emitted within the body Radioactive The body is equally exposed to radiation in both cases. materials "Radiation exposure" refers to the situation where the body is in the presence of radiation. There are two types of radiation exposure, "internal exposure" and "external exposure." External exposure means to receive radiation that comes from radioactive materials existing on the ground, suspended in the air, or attached to clothes or the surface of the body (p.25 of Vol. 1, "External Exposure and Skin"). Conversely, internal exposure is caused (i) when a person has a meal and takes in radioactive materials in the food or drink (ingestion); (ii) when a person breathes in radioactive materials in the air (inhalation); (iii) when radioactive materials are absorbed through the skin (percutaneous absorption); (iv) when radioactive materials enter the body from a wound (wound contamination); and (v) when radiopharmaceuticals containing radioactive materials are administered for the purpose of medical treatment. Once radioactive materials enter the body, the body will continue to be exposed to radiation until the radioactive materials are excreted in the urine or feces (biological half-life) or as the radioactivity weakens over time (p.26 of Vol. 1, "Internal Exposure"). The difference between internal exposure and external exposure lies in whether the source that emits radiation is inside or outside the body. -
Radiation Safety
Ionizing Radiation Exposure from Radiologic Imaging Background The current and common unit of measurement of “absorbed” ionizing radiation is a milliSievert (mSv). Chest, abdomen or The increased use of diagnostic imaging requiring the use of pelvis CTs will typically expose one to between 6 – 8 mSv. “ionizing radiation,” the rapidly expanding use of computed tomography in the emergency setting, the introduction Specifically, a CT coronary angiogram may carry an of multi-detector CT units and newly reported concerns overall effective radiation dose in a 20 mSv range; the related to the human consequences of low-level radiation organ equivalent dose is quite different.7 Anthromorphic exposure have revitalized a long-standing concern over the mathematical phantoms have shown that such studies quantification and management of an individual’ s cumulative will expose 20-year-old female breast tissue to an organ 1,2,3 “medical” radiation exposure. Studies have shown that equivalent dose of 75 – 80 mSv, and lung tissue as high as 90 many physicians, including radiologists, have developed a mSv. The cancer incidence for a 20-year-old in this example is misconception that the shorter imaging acquisition times believed to be in the one in 143 range…quite significant! With have resulted in lower doses of radiation, when in fact many improvements in technology and CCTA imaging protocols, times the opposite is true. The multi-detector CT units today, effective dose has been reduced significantly, to less than 10 even with shorter scan times, expose patients to higher doses mSv in many cases. of radiation per scan than earlier units. -
4 Radiation Safety Principles
4 Radiation Safety Principles Radiation doses to workers can come from two types of exposures, external and internal. External exposure results from radiation sources outside of the body emitting radiation of sufficient energy to penetrate the body and potentially damage cells and tissues deep in the body. External exposure is type and energy dependent. As a general rule, x-rays, γ-rays and neutrons are external hazards as are ß-particles emitted with energies exceeding 200 3 14 35 63 keV (Emax > 200 keV). Beta particles with Emax < 200 keV ( H, C, S, Ni) do not travel far in air and most of the beta particles (i.e., > 90%) do not have enough energy to penetrate deeper than 0.1 mm of skin. Internal exposure comes from radioactivity taken into the body (e.g., inhalation, ingestion, or absorption through the skin) which irradi- ates surrounding cells and tissues. Both types of exposure carry potential risk. Thus, when using radiation or radio- active materials, workers must understand and implement basic radiation safety principles to protect themselves and others from the radiation energy emitted by the radioactive materials and from radioactive contamination in the work place. The principles of time, distance and shielding apply only to external hazards. 4.1 Time The linear no-threshold dose-response model assumes no cellular repair and that radiation damage is cumulative. Therefore, the length of time that is spent handling a source of radiation determines the radiation exposure received and the consequent injury risk. Most work situations require workers to handle radioactive materi- als for short periods. -
Radiation Safety
RADIATION SAFETY FOR LABORATORY WORKERS RADIATION SAFETY PROGRAM DEPARTMENT OF ENVIRONMENTAL HEALTH, SAFETY AND RISK MANAGEMENT UNIVERSITY OF WISCONSIN-MILWAUKEE P.O. BOX 413 LAPHAM HALL, ROOM B10 MILWAUKEE, WISCONSIN 53201 (414) 229-4275 SEPTEMBER 1997 (REVISED FROM JANUARY 1995 EDITION) CHAPTER 1 RADIATION AND RADIOISOTOPES Radiation is simply the movement of energy through space or another media in the form of waves, particles, or rays. Radioactivity is the name given to the natural breakup of atoms which spontaneously emit particles or gamma/X energies following unstable atomic configuration of the nucleus, electron capture or spontaneous fission. ATOMIC STRUCTURE The universe is filled with matter composed of elements and compounds. Elements are substances that cannot be broken down into simpler substances by ordinary chemical processes (e.g., oxygen) while compounds consist of two or more elements chemically linked in definite proportions. Water, a compound, consists of two hydrogen and one oxygen atom as shown in its formula H2O. While it may appear that the atom is the basic building block of nature, the atom itself is composed of three smaller, more fundamental particles called protons, neutrons and electrons. The proton (p) is a positively charged particle with a magnitude one charge unit (1.602 x 10-19 coulomb) and a mass of approximately one atomic mass unit (1 amu = 1.66x10-24 gram). The electron (e-) is a negatively charged particle and has the same magnitude charge (1.602 x 10-19 coulomb) as the proton. The electron has a negligible mass of only 1/1840 atomic mass units. The neutron, (n) is an uncharged particle that is often thought of as a combination of a proton and an electron because it is electrically neutral and has a mass of approximately one atomic mass unit. -
Radiation Exposure from Medical Diagnostic Imaging Procedures
HEALTH PHYSICS SOCIETY Specialist in Radiation Safety RADIATION EXPOSURE FROM MEDICAL DIAGNOSTIC IMAGING PROCEDURES HEALTH PHYSICS SOCIETY FACT SHEET Ionizing radiation is used daily in hospitals and clinics to perform diagnostic imaging procedures. For the purposes of this fact sheet, the word radiation refers to ionizing radiation. The most commonly mentioned forms of ionizing radiation are x rays and gamma rays. Procedures that use radiation are necessary for accurate diagnosis of disease and injury. They provide important information about your health to your doctor and help ensure that you receive appropriate care. Physicians and technologists performing these procedures are trained to use the minimum amount of radiation necessary for the procedure. Benefits from the medical procedure greatly outweigh any potential small risk of harm from the amount of radiation used. Which types of diagnostic imaging procedures use radiation? • In x-ray procedures, x rays pass through the body to form pictures on film or on a computer or television monitor, which are viewed by a radiologist. If you have an x-ray test, it will be performed with a standard x-ray machine or with a more sophisticated x-ray machine called a CT or CAT scan machine. • In nuclear medicine procedures, a very small amount of radioactive material is inhaled, injected, or swallowed by the patient. If you have a nuclear medicine exam, a special camera will be used to detect energy given off by the radioactive material in your body and form a picture of your organs and their function on a computer monitor. A nuclear medicine physician views these pictures.