Finals Flashcards
The production of x-ray photons by the sudden deceleration of high-speed electrons is termed:
Bremsstrahlung
The automatic exposure device that is located immediately under the x-ray table is the
Ionization chamber
Which of the following may be sued to express exposure in air?
1. Air kerma
2. Gy
3.Sv
4. RBE
Air kerma
A PA skull will reduce the dose to the
Eyes
If 300 mA has been selected for a particular exposure, what exposure time would be required to produce 6 mAs?
20 ms
Types of gonadal shielding include which of the following?
1. Flat Contact
2. Shaped contrast (contour)
3. Shadow
1,2, and 3
For radiographic examinations of the chest, it is generally preferred that the chest be examined in the PA projection to decrease dose to
Breast
Which of the following would be useful for an examination of a patient suffering from Parkinson’s disease?
1. Short exposure time
2. Decreases SID
3. Compensating filtration
1 only
Which of the following contributes most to the patient dose?
1. Photoelectric effect
2. Compton scatter
3. Classic scatter
4. Thompson scatter
1
The primary function of filtration is to reduce
Patient skin dose
How many tube target interactions are there in x-ray production?
2
The occupational dose to radiographers is measured in
Sv
Lead aprons are worn during fluoroscopy to protect the radiographer from exposure to radiation from
Compton scatter
For radiographic examinations of the skull, it is generally preferred that the skull be examined in the
PA projection
The type of radiation monitoring device that uses aluminum oxide as the detection material is
OSL
How is the ESE affected as the source-to-skin-distance (SSD) is increased?
ESE Decreases
What minimum total amount of filtration (inherent plus added) is required in x-ray equipment operated above 70 kVp?
2.5 mm Al equivalent
How are wavelength and energy related?
Inversely
The intensity of the beam has what relationship with distance?
Direct
Filters used in radiographic x-ray tubes generally are composed of
Aluminum
With milliamperes (mA) increased to maintain output intensity, how is the ESE affected as the source-to-skin-distance (SSD) is increased?
ESE Decreases
The exposure received at the skin entrance to a patient’s body is known as
Entrance skin exposure (ESE )
Aluminum filtration has its greatest effect on
Low energy X-ray photons
A significant reduction in patient dose can be achieved by
Increasing kVp/decreasing mAs
Because of the anode heel effect, the intensity of the x-ray beam is greatest at the
Cathode end
The advantages of beam restriction include which of the following?
1, Less scattered radiation is produced
2. Less biologic material is irradiated
3. Less total filtration will be necessary
1 and 2
Filtration will _____the ESE.
Decrease
When mAs is increased, patient dose will
Increase
If a conscientious radiographer chooses the appropriate exposure/technical factors dose can be reduced by at least
50%
Some patients, such as infants and children, are unable to maintain the necessary radiographic position without assistance. If mechanical restraining devices cannot be used, who of the following should be the first choice to help immobilize the patient?
Patients father
The principle factors affecting scatter production are
Kv
Subject density
The most commonly employed beam restrictor in radiography is the
Collimator
Which x-ray interaction is scatter produced in?
Compton scattering
Which x-ray interactions are predominantly seen in the diagnostic x-ray range?
Photoelectric absorption
Compton scattering
The amount of kV should be selected based on the size of the
Part being examined
