Test 1 Flashcards
8 basic safety rules when taking radiographs
- Minimize time
- Maximize distance
- Maximize shielding
- Never allow any part of the body to be in the primary beam
- Always wear a personal radiation monitoring device
- Use mechanical restraint when possible
- Collimation of the beam
- Equipment
Rules for dosimeter
- Must not be taken home
- Must be stored in a location where it is not exposed to radiation
- Must not be exposed to heat or sunlight
- Must be worn at the facility where it is registered
- Should be worn attached to the outside of the thyroid protector
- Should not be shared with another employee
- Should not be left on a lab coat or anything hung up in rad room
Information required on a radiation label (6)
- Name of vet (UGRC)
- Name of animal (patient ID, owners last name)
- Log number
- Date of radiograph
- Initials of person creating radiograph (group/initals)
- R or L ID marker
Requirement needed to produce x-rays
- Source of electrons (tungsten filament)
- A method of accelerating the electrons (mA)
- An obstacle-free path
- A target to interact with to create radiation
- An envelope (tube) to provide a vacuum environment
Legal requirements pertaining to radiation
- Required by law to take 2 views of each anatomical part
- Required to keep rads for 5 years or until the animal dies
- Log book should include various kinds of information (ie. log #, client/pt name, species, body part, position, kVp mA and mAs, initials/group #)
Radiolucent
Materials that allow the passage of x-rays working affecting the radiograph
Ex. Foam wedges and tape
Radiopaque
Substances that do not allow the passage of x-rays without affecting the radiograph
Ex. Sand bags, metal trough, lead gloves
ALARA definition
As Low As Reasonably Achievable
What is radiation?
Energy in the form of waves of particles
What is non-ionizing radiation?
Radiation that has less every, does not produce ions
What is ionizing radiation?
Can knock electrons out of their orbit around the atom, changing the electron-proton balance, giving the atom a positive charge
What are x-rays?
Electromagnetic radiation- very short wavelengths of electromagnetic radiation which originates from the extra-nuclear part of an atom
What is a radiograph?
A photographic image produced by a beam of penetrating ionizing radiation after passing through an object/patient
Define Flexion
Decreased angle of the joint
Define extension
Increase in the angle of the joint
Define differential absorption
Characteristic of creating an image on a radiograph
Define atomic number and give examples
The number of protons in the atom
Lead - 87
Bone - 14
Soft tissue - 6
What is the rate of absorption affected by?
Density and thickness
Where does radiation exposure come from?
- Primary beam
- Scatter radiation
- X-ray tube head
- Fluoroscopy
What is somatic damage?
Damage to the body induced by radiation that becomes manifest within the lifetime of recipient
What is MPD?
Maximum Permissible Dose of radiation that a person may receive in each period
What does A.C stand for?
Alternating Current
Flows both ways (positive to negative)
What does D.C stand for?
Direct Current
One direction of flow
What is Focal Film distance?
Distance between the tube and the film or image receptor
Amount of absorption depends on…
The objects atomic number
The density of the object
The energy of the x-ray
Differential absorption
The characteristic of creating an image on a radiograph
Radiographic detail
The definition of the edge of an anatomical structure on a radiograph
15% rule
Used only to optimize kilovoltage because the body part has not been imaged satisfactorily
To increase density of a radiograph, you need to…
Increase mAs
Increase kVp
Geometric factors
Distortion and magnification
Geometric disorientation
A change in normal size and shape of an object on a finished radiograph due to the position and radiation source
Eliminating disorientation
- Object should be parallel to the film/image
- Object should be centered
- Object should be as close to casters as possible
Latent image
An invisible image on the x-ray film after it is exposed to ionizing radiation prior to processing
