Flashcards in Radiology Deck (188)
What are 10 things you can do to decrease your radiation exposure?
1. never hold the x-ray tube
2. wear film or TLD badges near the collar
3. maintain darkroom chemicals in good operating condition
4. have the x-ray machine calibrated annually
5. don't aim the x-ray beam directly at any personnel
6. use a 2.5mm aluminum filter to remove soft x-rays
7. use collimation whenever possible to decrease field size and scatter radiation
8. never let any part of the body within the primary beam
9. use mechanical restraints whenever possible (sandbags)
10. use chemical restraint whenever possible (anesthetize)
What is the name of the radiation monitoring device you wear?
film badge a type of dosimeter
What is the MPD? and who is responsible for setting dose limits?
maximum permissible dose is the maximum dose of radiation that a person may receive in a given period, NCRP national committee on radiation protection and measurements
The unit of absorbed dose is?
1 Gy =
The quantity of energy imparted by ionizing radiations to matter per unit of mass of the matter
The quantity obtained by multiplying the absorbed dose in tissue by the quality factor.
The unit of dose equivalent is?
What lead equivalent do gloves and gowns need to be in order to be safe?
at least 0.5mm thickness
How do you maintain protective gear?
aprons are hung vertically over a sound surface(not 3< cm in diameter) or laid flat when not in use, gloves are placed on vertical holders that allow air to circulate throughtout the inside, lead aprons and gloves should be inspected periodically for damage
Secondary radiation caused by interaction of the primary beam with objects in its path.
The amount of scatter radiation is determined by what 4 factors?
intensity of the beam, the composition of the structure being radiographed, the kVp level, and the thickness of the patient
What is primary radiation?
the path that the x-rays follow as they leave the tube
Several important factors must be considered if an accurate reproduction is to be made:
welfare of the patient, restraint and immobilization of the patient, minimal truama to the area of interest, and the least risk of exposing those assisting with the examination to radiation
What instrument is used to measure the anatomic area of interest? Measurements are in what increments?
a caliper measures part thickness in centimeters
What are the required views?
two views of each anatomic area taken at right angles to each other minimum
T/F X-rays produce a radiograph
The amount of electrical energy being applied to the anode
The amount of electrical energy being applied to anode and cathode to accelerate the electrons from the cathode to the anode
A number of x-rays traveling together through space at a rapid speed
A visible photograph record on film produced by x-rays passing though an object
A restricting device used to control the size of the primary beam
A decrease of x-ray intensity on the anode side of the x-ray beam caused by the anode target angle
Difference in density and mass of two adjacent anatomic structures
The distance between the source of x-rays and the image receptor or film
source image distance (SID) formerly called FFD
How does energy travel?
fast moving electrons is produced at the cathode(filament) and directed to the anode->as electrons collide and interact with the atoms of the target on the anode energy is produced
T/F 99% is the form of roentgen radiation and 1% is a great amount of heat.
_____ is the result of the interaction of the electrons and the atoms in the target.