Introduction to Radiation Protection Flashcards
The ability of x-rays to cause injury in normal tissue became apparent when?
Soon after its discovery in the early 1900’s.
X-rays produce positively and negatively charged particles when passing through matter and are therefore called:
ionizing radiation.
The production of ions is the event that may cause _____ in normal biologic tissue.
injury.
Consequences of ionization in human cells:
- Creation of unstable atoms.
- Production of free electrons.
- Production of low-energy X-ray photons.
- Creation of reactive free radicals capable of producing substances poisonous to the cell.
- Creation of new biologic molecules detrimental to the living cell.
- Injury to the cell that may manifest as abnormal function or loss of function.
What methods do radiologists and radiographers employ to limit radiation and minimize possibility of damage to biologic tissue?
Educated in safe operation of imaging equipment.
Use protective devices whenever possible.
Follow established procedures.
Select optimal technical factors.
Radiation safety is the responsibility of:
imaging personel.
Radiation Protection:
Effective measures employed by radiation workers to safeguard patients, personnel, and the general public from unnecessary exposure to ionizing radiation.
Effective measures employed by radiation workers to safeguard patients, personnel, and the general public from unnecessary exposure to ionizing radiation consists of:
tools and techniques that minimize radiation exposure while production optimal diagnostic images.
Harmful biologic effects:
Damage to living tissue of animals and humans exposed to ionizing radiation.
Patient assumes relatively small risk of exposure to radiation to:
obtain diagnostic information. Benefits of the exposure to radiation outweighs slight risk of inducing a radiogenic malignancy or genetic defects.
Diagnostic efficacy:
Degree to which the diagnostic study accurately reveals the presence or absence of disease in the patient.
What is the basis for determining whether an imaging procedure or practice is justified?
Diagnostic efficacy.
Occupational and nonoccupational doses (recommended by NCRP):
Upper boundary does of ionizing radiation that will result in a negligible (not zero) risk of bodily injury or genetic damage.
How are occupational and nonoccupational doses best accomplished?
using smallest radiation exposure that produces useful images and producing optimal images with first exposure.
ALARA is synonymous with the term:
Optimization for Radiation Protection (ORP)
ORP is concepts that are intended to:
keep radiation exposure and dose to lowest possible level, based on evidence compiled by scientists over past century.
ALARA philosophy should be part of health care facility’s
personal radiation control program.
Dose limits have not been established for the:
amount of radiation patient’s receive during imaging procedures.
Radiation induced cancer follows a ______ response so radiation exposures should always be kept ALARA.
nonthreshold.
ALARA principle provides regulatory agencies a method to:
compare amount of radiation various health care facilities use for specific imaging procedures.
If pts in a particular location were receiving on average approximately the same ESE for a specific imagine procedure in every health care facility in that same area:
then that ESE would represent the radiation exposure and consequent dose that is reasonably achieved within that specific location.
If one of the health care facilities in an area began giving its pts higher-radiation ESEs and subsequent doses, that institution:
would no longer be in compliance with ALARA standards.
Cardinal rules of radiation protection:
time, distance, shielding.
Applying cardinal rules to reduce dose to patient:
Reduce the amount of “beam-on” time.
Use as much distance between X-ray tube and patient.
Use appropriate gonadal and/or specific area shielding.
