GXMO Test Study Questions with
Verified Solutions
fetal exposure numbers: - ANSWERS-Most diagnostic radiographic procedures result in fetal
exposure of less than 0.01Gy. Studies show damage to newborn is likely for doses under 0.2 Gy.
Fetal risk is lowbelow 5 cGy(.005Gy),malformations significantly increase above 15 cGy
In what trimester is the fetus most radiosensitive? - ANSWERS-first trimester esp. in the CNS
and sensory organs
Irradiation of XmSv causes fetal death or malformity - ANSWERS-200mSv
During preimplantation embryonic death will occur if irradiation with x Gy, malformations
cannot occur during this stage - ANSWERS-0.05-0.15
how many doses of Gyt depress male sperm or delay/suppress menstruation? - ANSWERS-0.1
Gyt
Doses as low as X Gyt cause hematologic depression which can lead to anemia, infection, or
hemorrhage - ANSWERS-0.25
what phase can chromosomal damage from radiation be evaluated? - ANSWERS-metaphase
how many forms of patient identifiers do you need? - ANSWERS-2
,a complete history of patient involves: - ANSWERS-when it occurred, mechanism of injury,
things that make it better or worse, and verifying the correct part and side as what has been
recorded
collimator - ANSWERS-beam restricting device with 2-3 sets of lead shutters to limit the x-ray
beam to change the field size and shape. Equipped with a light to display the exposure field.
film-based cassette - ANSWERS-image is captured on film to be processed. The cassette contains
the film and 1-2 screens in a protective case. The screens have their own protection with the
phosphor and reflective layers. The film goes under the screen with the emulsion layer facing it.
CR-based cassette - ANSWERS-houses the imaging plate which acts through phosphors. The IP
has protective layers, backing with phosphors and reflective layers between similar to film. The
phosphor is a photostimulable phosphor of barium fluoride crystals with europium.
DR-based cassette - ANSWERS-can be either direct or indirect. Indirect uses a CCD, which is light
sensitive with a wide dynamic range. The phosphor used is made of cesium iodine, which is
then converted to electrical signal via amorphous silicon thin film transistors. Direct conversion
for goes the phosphor portion. Amorphous selenium detectors convert radiation to electrical
signals.
sponges - ANSWERS-radiolucent positioning aid
immobilization devices - ANSWERS-used to prevent undesired motion during procedures and
does not require a physician's order. This includes sandbags, plexiglass, and compression bands
ceiling mount - ANSWERS-also known as overhead tube assembly. Most widely used and most
versatile. Two rails are mounted to the ceiling with the tube suspend and allows the most
flexibility for cross table examinations
transverse - ANSWERS-across the table at right angles to longitudinal
, Longitudinal - ANSWERS-along the axis of the table
verticle - ANSWERS-up or down; increasing or decreasing the distance between table and tube
Angle and tilt - ANSWERS-allows the tube to angle along the long axis of the table and aims
toward the wall rather than the tab
detent - ANSWERS-mechanism to stop a moving part at a specific location. Most often used to
align the tube with the bucky and reach appropriate SID.
primary x-ray beam - ANSWERS-X-rays formed within the focal spot target on the anode which
diverge in a cone shape. Used to form the radiation field. The photon in the center forms the
central ray.
what are some properties of x-ray beam? - ANSWERS-invisible, electrically neutral, no mass,
travel at speed of light in a vacuum, cannot be optically focused, polyenergentic/heterogenous
beams, produce a range of energies, cause some substances to fluoresce, cause chemical
changes
floating - ANSWERS-table movement that allows the table to move independently
Trendelenburg - ANSWERS-supine position in which the patients head is lower than the feet
Under-table Bucky (grid) - ANSWERS-device placed between the patient and IR to prevent
scatter radiation from reaching the IR. Usually under the table with moving tray to house the IR.
Made of thin lead strips with radiolucent interspace material
Verified Solutions
fetal exposure numbers: - ANSWERS-Most diagnostic radiographic procedures result in fetal
exposure of less than 0.01Gy. Studies show damage to newborn is likely for doses under 0.2 Gy.
Fetal risk is lowbelow 5 cGy(.005Gy),malformations significantly increase above 15 cGy
In what trimester is the fetus most radiosensitive? - ANSWERS-first trimester esp. in the CNS
and sensory organs
Irradiation of XmSv causes fetal death or malformity - ANSWERS-200mSv
During preimplantation embryonic death will occur if irradiation with x Gy, malformations
cannot occur during this stage - ANSWERS-0.05-0.15
how many doses of Gyt depress male sperm or delay/suppress menstruation? - ANSWERS-0.1
Gyt
Doses as low as X Gyt cause hematologic depression which can lead to anemia, infection, or
hemorrhage - ANSWERS-0.25
what phase can chromosomal damage from radiation be evaluated? - ANSWERS-metaphase
how many forms of patient identifiers do you need? - ANSWERS-2
,a complete history of patient involves: - ANSWERS-when it occurred, mechanism of injury,
things that make it better or worse, and verifying the correct part and side as what has been
recorded
collimator - ANSWERS-beam restricting device with 2-3 sets of lead shutters to limit the x-ray
beam to change the field size and shape. Equipped with a light to display the exposure field.
film-based cassette - ANSWERS-image is captured on film to be processed. The cassette contains
the film and 1-2 screens in a protective case. The screens have their own protection with the
phosphor and reflective layers. The film goes under the screen with the emulsion layer facing it.
CR-based cassette - ANSWERS-houses the imaging plate which acts through phosphors. The IP
has protective layers, backing with phosphors and reflective layers between similar to film. The
phosphor is a photostimulable phosphor of barium fluoride crystals with europium.
DR-based cassette - ANSWERS-can be either direct or indirect. Indirect uses a CCD, which is light
sensitive with a wide dynamic range. The phosphor used is made of cesium iodine, which is
then converted to electrical signal via amorphous silicon thin film transistors. Direct conversion
for goes the phosphor portion. Amorphous selenium detectors convert radiation to electrical
signals.
sponges - ANSWERS-radiolucent positioning aid
immobilization devices - ANSWERS-used to prevent undesired motion during procedures and
does not require a physician's order. This includes sandbags, plexiglass, and compression bands
ceiling mount - ANSWERS-also known as overhead tube assembly. Most widely used and most
versatile. Two rails are mounted to the ceiling with the tube suspend and allows the most
flexibility for cross table examinations
transverse - ANSWERS-across the table at right angles to longitudinal
, Longitudinal - ANSWERS-along the axis of the table
verticle - ANSWERS-up or down; increasing or decreasing the distance between table and tube
Angle and tilt - ANSWERS-allows the tube to angle along the long axis of the table and aims
toward the wall rather than the tab
detent - ANSWERS-mechanism to stop a moving part at a specific location. Most often used to
align the tube with the bucky and reach appropriate SID.
primary x-ray beam - ANSWERS-X-rays formed within the focal spot target on the anode which
diverge in a cone shape. Used to form the radiation field. The photon in the center forms the
central ray.
what are some properties of x-ray beam? - ANSWERS-invisible, electrically neutral, no mass,
travel at speed of light in a vacuum, cannot be optically focused, polyenergentic/heterogenous
beams, produce a range of energies, cause some substances to fluoresce, cause chemical
changes
floating - ANSWERS-table movement that allows the table to move independently
Trendelenburg - ANSWERS-supine position in which the patients head is lower than the feet
Under-table Bucky (grid) - ANSWERS-device placed between the patient and IR to prevent
scatter radiation from reaching the IR. Usually under the table with moving tray to house the IR.
Made of thin lead strips with radiolucent interspace material
