Fluoroscopy Exam UPDATED ACTUAL
Questions and CORRECT Answers
What is the maximum mA used when operating fluoroscopy? - CORRECT ANSWER -
The maximum mA used during fluoroscopy is 5mA or less.
Despite lower mA, the patient dose is higher during fluoroscopy than it is in radiographic exams
because the x-ray beam exposes the patient for a considerably longer period of time.
What structure of the eye is responsible for scotopic vision? - CORRECT ANSWER -
Rods cell (almost entirely responsible for night vision) more sensitive than cone cells.
Personnel wearing protective lead aprons during a procedure where the minimum exposure rate
is 5mR/hr must contain the equivalent of what
thickness in lead? - CORRECT ANSWER - .25mm lead equivalent (according to NCRP)
Total Brightness Gain is determined by which 2 factors? - CORRECT ANSWER - It is
determined by minification gain & flux gain.
Total brightness gain is a measurement of the increase in image intensity achieved by an image
intensification tube.
Cones are used primarily for daylight vision. This type of vision is referred to as? - CORRECT
ANSWER - Photopic vision
What is the minimum filtration required for fluoroscopy machines? - CORRECT
ANSWER - 2.5mm Aluminum or Aluminum equivalent
In DF, spatial resolution is determined by what 2 components? - CORRECT ANSWER -
In DF, spatial resolution is determined both by image matrix and by the size of the image
intensifier.
,Spatial resolution is limited by pixel size.
What is the formula used to determine brightness gain? - CORRECT ANSWER -
Minification Gain X Flux Gain
What is the Input Phosphor is made up of? - CORRECT ANSWER - Cesium Iodide (CsI)
What does the Image Intensifier of a fluoroscopic machine do? - CORRECT ANSWER -
The Image Intensifier raises the intensity of available light into the cone-vision region, where
visual acuity is the greatest.
What is NOT a non-stochastic effect? - CORRECT ANSWER - They do not cause genetic
effects (cancer)
Non-stochastic effects are biologic somatic effects that exhibit a threshold dose below which the
effect does not occur.
Stochastic Effects are? - CORRECT ANSWER - Stochastic effects are effects that occur
by chance and which may occur without a threshold level of dose.
The probability is proportional to the dose and the severity is independent of
the dose.
In the context of radiation protection, the main stochastic effect is cancer.
Radiographs and image intensified fluoroscopic images are best visualized under what
illumination levels? - CORRECT ANSWER - under illumination levels of 10 to 1000ml
(milliamberts)
, Which part of the eye behaves like a diaphragm of a photographic camera to control the amount
of light emitted to the eye? - CORRECT ANSWER - The Iris
The iris is located between the cornea & the
lens of the eye.
During low light conditions, the iris dilates & allows for more light to enter.
What is vignetting? - CORRECT ANSWER - Vignetting is the loss of brightness at the
edge of the image.
The following factors influence dose rate at a table top fluoroscopic machine: - CORRECT
ANSWER - mA
kVp
Collimation
Filtration
Exposure time
Target panel distance
Fovea Centralis is? - CORRECT ANSWER - Fovea Centralis are cones concentrated at the
center of the retina.
What is the magnification for an image viewed with a 9" image intensifier tube that has used a 5"
diameter area during magnification? - CORRECT ANSWER - Magnification= input
screen / diameter of input screen used during magnification.
9/5
magnification = 1.8
Questions and CORRECT Answers
What is the maximum mA used when operating fluoroscopy? - CORRECT ANSWER -
The maximum mA used during fluoroscopy is 5mA or less.
Despite lower mA, the patient dose is higher during fluoroscopy than it is in radiographic exams
because the x-ray beam exposes the patient for a considerably longer period of time.
What structure of the eye is responsible for scotopic vision? - CORRECT ANSWER -
Rods cell (almost entirely responsible for night vision) more sensitive than cone cells.
Personnel wearing protective lead aprons during a procedure where the minimum exposure rate
is 5mR/hr must contain the equivalent of what
thickness in lead? - CORRECT ANSWER - .25mm lead equivalent (according to NCRP)
Total Brightness Gain is determined by which 2 factors? - CORRECT ANSWER - It is
determined by minification gain & flux gain.
Total brightness gain is a measurement of the increase in image intensity achieved by an image
intensification tube.
Cones are used primarily for daylight vision. This type of vision is referred to as? - CORRECT
ANSWER - Photopic vision
What is the minimum filtration required for fluoroscopy machines? - CORRECT
ANSWER - 2.5mm Aluminum or Aluminum equivalent
In DF, spatial resolution is determined by what 2 components? - CORRECT ANSWER -
In DF, spatial resolution is determined both by image matrix and by the size of the image
intensifier.
,Spatial resolution is limited by pixel size.
What is the formula used to determine brightness gain? - CORRECT ANSWER -
Minification Gain X Flux Gain
What is the Input Phosphor is made up of? - CORRECT ANSWER - Cesium Iodide (CsI)
What does the Image Intensifier of a fluoroscopic machine do? - CORRECT ANSWER -
The Image Intensifier raises the intensity of available light into the cone-vision region, where
visual acuity is the greatest.
What is NOT a non-stochastic effect? - CORRECT ANSWER - They do not cause genetic
effects (cancer)
Non-stochastic effects are biologic somatic effects that exhibit a threshold dose below which the
effect does not occur.
Stochastic Effects are? - CORRECT ANSWER - Stochastic effects are effects that occur
by chance and which may occur without a threshold level of dose.
The probability is proportional to the dose and the severity is independent of
the dose.
In the context of radiation protection, the main stochastic effect is cancer.
Radiographs and image intensified fluoroscopic images are best visualized under what
illumination levels? - CORRECT ANSWER - under illumination levels of 10 to 1000ml
(milliamberts)
, Which part of the eye behaves like a diaphragm of a photographic camera to control the amount
of light emitted to the eye? - CORRECT ANSWER - The Iris
The iris is located between the cornea & the
lens of the eye.
During low light conditions, the iris dilates & allows for more light to enter.
What is vignetting? - CORRECT ANSWER - Vignetting is the loss of brightness at the
edge of the image.
The following factors influence dose rate at a table top fluoroscopic machine: - CORRECT
ANSWER - mA
kVp
Collimation
Filtration
Exposure time
Target panel distance
Fovea Centralis is? - CORRECT ANSWER - Fovea Centralis are cones concentrated at the
center of the retina.
What is the magnification for an image viewed with a 9" image intensifier tube that has used a 5"
diameter area during magnification? - CORRECT ANSWER - Magnification= input
screen / diameter of input screen used during magnification.
9/5
magnification = 1.8
