Complete Solutions
An image intensifier has a 5 cm output phosphor and a 45 cm
input phosphor. the brightness gain is 10,000. the flux gain is
approximately
A. 10
B. 80
C. 120
d. 1000
E. 5000 Correct Answers 120
An image the displays vignetting
A. is dim around the periphery
B. Is dim in the center
C. Has higher contrast resolution
D. Has higher spatial resolution
E. Shows the barrel stay artifact Correct Answers is dim around
the periphery
at which stage of image intensified fluoroscopy is the number of
image - forming photons lowest
A. Entering the input phosphor
B. Entering the photo-cathode
C. leaving the input phosphor
D. leaving the output phosphor
E. leaving the photocathode Correct Answers Entering the input
phosphor
Automatic brightness stabilization ABS is designed to
compensate for changes in which of the following?
,A. Examination time
B. Patient composition
C. Patient dose
D. patient positioning
E. Technique selection Correct Answers Patient composition
Compared with a radiogrpahic examination the primary purpose
of a fluoroscopic examination is to visualize:
A. Cross sectional images
B. Dynamic images
C. Longitudinal images
D. Static images
E. Transverse images Correct Answers Dynamic images
compared with radiography, the x-ray technique required for
fluoroscopy calls for which of the following?
A. higher kVp
B. Higher mA
C. Lower kVp
D. Lower mA
E. shorter exposure Correct Answers Lower mA
fluoroscopic television operates at a frame rate of ;
A. 30 f/s
B. 60 f/s
C. 262.5 f/S
D. 525 f/s
E. 1024 f/s Correct Answers 30 f/s
Fluoroscopy normally requires a tube current of :
A. 0.1- 1.0 mA
, B. 1-5 mA
C. 5-10 mA
D. 10-100 mA
E. 10-1000mA Correct Answers 1-5 mA
Horizontal television resolution is principally limited by which
of the following:
A. Band pass
B. Field rate
C. frame rate
D. lines per frame
E. Modulation Correct Answers Band pass
if an image intensifier is described as a 25/12 tube the 25/12
refers to which of the following ?
A, Area of the input phosphor in square inches
B. diameter of the input phosphor in inches
C. diameter of the output phosphor in centimeters
D. Radius of the input phosphor in inches
E. Radius of the output phosphor in centimeters Correct
Answers diameter of the input phosphor in inches
Image intensifier brightness gain increases with increasing
a. Flux gain
B. kVp
C. mA
D. Output phosphor size
E. Radiation exposure Correct Answers Flux gain
In a 10/7/5 image intensifier:
A. contrast resolution is best int he 10 mode