NMTCB-CT UPDATED ACTUAL Questions and CORRECT Answers
Where are x-rays made? in the electron shell structure of an atom
energetic electrons pass very near the nucleus of an atom.
The strong forces of th positive charged atom causes the
What is Bremsstrahlung radiation? negatively charged electron to decelerate; the path of the
electron is changed, and some of the kinetic energy of the
electron is lost, and converted into x-rays
following the ionization of an atom that leaves an inner
shell, outer shell electrons drop down to refill the inner
what is characteristic x-ray radiation?
shell. As these electrons drop down, they lose energy,
which is released as x-rays.
(used before x-rays enter the patient) defines the beam
What does pre-collimation do? shape and width (which is usually fan or cone shaped)
and protects the patient from excess radiation
(used to reduce scatter after leaving the patient) is used
What does post-collimation do?
before the radiation strikes the detectors
A: less volume averaging
B: increased spatial resolution
C: decreased spatial resolution
What are advantages of thinner collimation?
D: fewer artifacts
E: all of the above
F: a,b,d **
True or false: in CT, the gantry rotates continuously in one
true
direction on a slip ring system
What is a scout imaged used for? Positioning /localization
the ratio of patient's movements through the gantry dur-
ing one 360 degree beam rotation relative to the beam
Pitch collimation (in single slice CT)
The table distance traveled in 1 gantry rotation of 360o
Where are x-rays made? in the electron shell structure of an atom
energetic electrons pass very near the nucleus of an atom.
The strong forces of th positive charged atom causes the
What is Bremsstrahlung radiation? negatively charged electron to decelerate; the path of the
electron is changed, and some of the kinetic energy of the
electron is lost, and converted into x-rays
following the ionization of an atom that leaves an inner
shell, outer shell electrons drop down to refill the inner
what is characteristic x-ray radiation?
shell. As these electrons drop down, they lose energy,
which is released as x-rays.
(used before x-rays enter the patient) defines the beam
What does pre-collimation do? shape and width (which is usually fan or cone shaped)
and protects the patient from excess radiation
(used to reduce scatter after leaving the patient) is used
What does post-collimation do?
before the radiation strikes the detectors
A: less volume averaging
B: increased spatial resolution
C: decreased spatial resolution
What are advantages of thinner collimation?
D: fewer artifacts
E: all of the above
F: a,b,d **
True or false: in CT, the gantry rotates continuously in one
true
direction on a slip ring system
What is a scout imaged used for? Positioning /localization
the ratio of patient's movements through the gantry dur-
ing one 360 degree beam rotation relative to the beam
Pitch collimation (in single slice CT)
The table distance traveled in 1 gantry rotation of 360o
