Radiation concepts Flashcards
what type of energy is used for radiographs?
electric energy
what are the components of electromagnetic production?
wavelength, frequency, and energy
x-ray wavelengths
fall in between gamma and ultraviolet wavelengths
compromised of frequency and amplitude (height of wave)
x-ray frequency (Hz)
number of waveforms that strike an object during a given time period
x-ray energy (eV)
long wavelength has a low frequency, is weak, and requires more time to be produced
short wavelengths have a high frequency, are powerful, and require less time to be produced
who discovered x-rays?
Professor Wilhelm Rontgen
what are the 12 properties of x-rays?
- highly penetrating invisible rays that form electromagnetic radiation
- electrically neutral and not affected by electric or magnetic fields
- produce a wide variety of energies and wavelengths
- release small amounts of heat as they pass through matter
- travel in straight lines
- travel at speed of light in a vacuum
- ionize matter
- cause florescence of specific crystals
- not focused by lens
- affect photographic film
- create chemical and biological changes in matter due to ionization and excitation
- produce secondary and scatter radiation
what are the different parts of an x-ray machine?
x-ray tube head, x-ray control center, tabletop, Bucky tray, transformer, rectifier
what is located inside the x-ray tube head?
anode, cathode, glass enclosure, and window
what is the focusing cup and what is inside of it?
the cathode is inside of the focusing cup
it allows for excited electrons to be released in a straight pattern directed toward a focused target on the anode
what is the energy like when from the time of contact of the electrons to the anode?
99% heat and 1% x-rays
what are the different types of anodes?
rotating: used on stationary machines, disc shaped with angled edge
stationary: used in portable x-ray units, uses angled block instead of disc
anode heel effect
all rotating anodes have a set degree of angulation that results in partial limitation of the x-ray beam on the anode side of the x-ray tube as compared with the cathode side
what is contained inside the glass enclosure?
positively charged anode and negatively charged cathode in a vacuum sealed area which prevents dust particles from interfering with the electron’s movement
what does the Bucky tray do?
holds the x-ray film cassette under the tabletop
what is included in the control center?
on/off switch, kVp selector, mAs selector, time selector, x-ray prep, x-ray exposure button
what does the step-up transformer do?
increase the voltage to heat the filament
what does the step-down transformer do?
decreases the voltage to a pre-set number
what are the 3 different levels that the rectifiers work on?
half-wave rectification: allows for electrons to move from the cathode to the anode on the positive movement of the incoming current resulting in a short exposure time
full wave rectification: converts negative movement into positive movement so both positive and negative movements can be used
3-phase approach: results in a more continuous movement which allows for increased energy, more electrons, and more constant energy in the x-ray beam
radiographic study
all views taken of the same body part on the same patient at the same time
what is included in a label on a folder containing a radiographic study?
patient and client name, date, views taken
what information is included in a radiology log?
client’s name, patient’s name, body part radiographed, position, kVp and mAs settings used, initials/signature of the vet tech
what is DICOM?
an acronym that refers to digital imagining and communications in medicine
