Exam 1 Flashcards
Which is not considered one of the three major components of x-ray machines?
x-ray table
What are three major components of x-ray machines?
- Tube
- Console
- Generator
In the NUHS clinic, which radiography system is used?
Computed radiography
The electrical potential is measured in what unit?
Volts
What is the electrical current measured in what units?
Amps (Amperes)
Energy that is in transit as particles or electromagnetic waves can be defined as what?
Radiation
When an x-ray is being produced with tungsten anode at 100kVp is primarily what type of radiation?
Bremsstrahlung radiation
What type of energy is produced in the production of an x-ray?
Thermal energy production
In dealing with x-rays reacting with matter, what results in the release of significant SECONDARY RADIATION?
Compton scatter interaction
**In dealing with x-rays reacting with matter, what results in COMPLETE ABSORPTION of incident photon energy at diagnostic radiation energy levels?
Photoelectric interaction
Within the diagnostic range of x-ray energies, what happens to the PROBABILITY OF PHOTOELECTRIC INTERACTION as photon energy increases?
Photoelectric interaction DECREASES
Within the diagnostic range of x-ray energies, WHICH INTERACTION PREDOMINATES AS PHOTON ENERGY INCREASES?
Compton scatter interaction
Which of the following describes the relationship of the atom number (Z) of the absorbing material to the probability of photoelectric interactions?
Increased Z results in increased probability
FIltration is used in diagnostic radiography to do what?
Absorb low energy x-rays
The filament focusing cup carries an electrical charge to control the angular divergence of the photon beam; this charge is…
Negative
Question was something, apparently the answer was Radon…
Radon #16
X-ray QUANTITY is increased in direct proportion to an increase in what measure?
mAs
Which one of these facts is the basis for the following technology directive? -“the anode should be up for upright radiography and the thinner part should be toward the anode in recumbent radiography.”
Anode heel effect
The anode side of the primary beam is weaker than the cathode side because:
Photons are absorbed and attenuated as they travel through the tungsten of the electrode
The number of electrons accelerated across an x-ray tube is determined by:
Filament current
If you are performing an AP Lat Cervical study and you accidentally set your FFD at 40 inches instead of 72 inches, which of the following will result?
Your film will be 4 times too DARK
Penumbra will be minimized by:
Decreasing OFD (object-film distance)
If you are taking chest x-rays setting the kVp to 120 and the exposure time to 0.2 seconds with an mA setting of 150mA, will this be safe for the x-ray tube based on the tube rating chart 1?
NO
If you are taking a lateral lumbar x-ray setting the kVp and the exposure time to 1.0 seconds, which would be the highest allowable mA based on the tube rating chart 1?
150mA
A patient presented with pain along the lateral aspect of the right upper rib cage following blunt trauma. The first x-ray of the right upper rib cage was taken with technical factors of 90kVp and 16mAs. The film density (optical density) is in the diagnostic range however, the contrast of the image is somewhat poor and you want to retake this view. Which one is the best technical factor to increase the contrast (short scale of gray) and keel the film density the same?
76kVp (16% reduction) and 32mAs
[decrease the kVp and increase the mAs]
Which of the following groups of exposure factors will produce the greatest radiographic density?
600mA, 0.05 second
Alternating electronic current sources produce:
Oscillatory flows of electrons
**Which generator system creates the LEAST amount of voltage ripple effect?
High frequency rectification
**Which generator system HELPS REDUCE THE PATIENT DOSE?
High frequency rectification
Under penetration of the image probably indicates:
Insufficient mAs
To make certain that the x-rays have dissipated after clinical radiography, one should wait at least _____ before entering the room.
No wait necessary
When is Compton type scatter radiation produced?
In the patient
The most prevalent x-ray interaction at diagnostic x-ray energies (60-150kVp) IN TISSUE is:
Compton
X-rays with energies below 10keV usually interact with matter by means of:
Coherent scattering
Which one of the x-ray interactions with matter does not impart any energy to the host tissue?
Classical
X-rays throughout the diagnostic range can undergo an interaction with OUTER SHELL ELECTRONS that not only scatter the x-ray but reduces its energy and ionizes the atom as well: this interaction is called:
Compton effect
As INCIDENT ENERGY INCREASES, there is a relative increase or decrease in COMPTON scattering relative to the photoelectrical effect?
Increase
As mass density of the absorber increases, there is a proportional increase or decrease in compton scattering?
Increase
X-rays in the diagnostic range undergo ionizing interactions with inner shell electrons; a K SHELL ELECTRON is removed and the resultant electron cascade results in the production of characteristic radiation. This interaction is called:
Photoelectric effect
Which interaction with matter will not occur unless the incident X-RAY ENERGY EQUAL TO OR SLIGHTLY GREATER THAN THE ELECTRON BINDING ENERGY?
Photoelectric effect
The COMBINATION OF COMPTON SCATTERING, PHOTOELECTRIC INTERACTION, and x-rays transmitted through the patient without interaction is responsible for:
Differential absorption
If one changes the technique from 70kVp at 200mAs to 70kVp at 400mAs, then the optical density on the radiograph will:
Double
Concerning the characteristics of differential absorption, as tissue atomic number increases the following will result:
-All the above or None of the above
Which is not considered features of hard x-rays?
Low frequency
Which of the statements is false regarding “line focus principle”?
This will increase the intensity of x-ray photon
Which type of radiation has the most energy?
x-rays
How much of a change in kVp is necessary for there to be a noticeable difference in the image appearance?
4%
In the production of Bremsstrahlung radiation, the incident electron:
Is deflected, with resulting energy loss
How much of a change in mAs is necessary for there to be a noticeable difference int he image appearance?
30%
Concerning the characteristics of DIFFERENTIAL ABSORPTION as x-ray energy increases, the following will result:
All the above
