Which of the following forms of resolution improves when frame rate increases?
B. temporal
Which of the following is consistent with improved temporal resolution?
A. higher frame rate
All of the following decrease temporal resolution except: A. lower frame rate
B. deeper imaging
C. multi-focus
D. narrower sector
D. narrower sector
A sonographer adjusts an ultrasound scan to double the depth of view from 5 cm to 10 cm. What happens to the frame rate?
it will be halved
frame rate and depth are inversely related
A sonographer adjusts an ultrasound scan to double the depth of view from 5 cm to 10 cm. If the frame rate remains the same, which of the following also occurs?
A. increased line density
B. wider sector
C. multi-focus imaging turned on
D. narrower sector
D. narrower sector
A sonographer adjusts an ultrasound machine to change the sector size from 90 to 45 degrees. Nothing else changes. What happens to the frame rate?
it is doubled because fewer pulses are needed to make the image
A sonographer adjusts an ultrasound system to change the sector size from 90 to 45 degrees. The frame rate was unchanged. What else must have happened?
C. line density was doubled
A sonographer, using a phased array ultrasound system, turns off the multi-focus feature. what is the most likely consequence of this action?
C. temporal resolution improves
A sonographer increases the line density from 1 line per degree of sector to 3 lines per degree of sector. What is the most likely consequence of this action?
A. temporal resolution decreases
A sonographer reduces the sector angle from 90 to 30 degrees. At the same time, the ultrasound system automatically increases the line density from 1 line per degree to 2 lines per degree. No other changes are made. What will happen to the frame rate?
increases frame rate
A sonographer reduces the sector angle from 90 to 30 degrees. At the same time, the ultrasound system automatically increases the line density from 1 line per degree to 3 lines per degree. No other changes are made. What will happen to the temporal resolution?
temporal resolution is unchanged
Which of the following is most important in determining the frame rate of a system?
A. speed of sound in the medium
Which of the following is most important in determining the frame rate of a system?
C. depth of view
What is the frame rate of each image of the ultrasound system is created in 0.02 sec (1/50 sec)?
50 Hz
What is the time needed to make a single image if the frame rate of ultrasound system is 20 Hz?
1/20 sec or 0.05 sec
True or False.
The critical factor in determining frame rate, line density, and imaging depth is transducer style
False.
the critical factor in determining frame rate, line density, and imaging depth is time.
True or False.
The number of lines per frame and the frame rate determine the frequency.
False.
determine the PRF
True or False.
The number of lines per frame and the frame rate determine the pulse repetition frequency.
True
True or False.
If the imaging depth of a scan is 15 cm and there are 100 lines in the image, then the number of pulses making up the scan is 1500.
False
100 pulses
True or False.
If the imaging depth of a scan is 15 cm and there are 100 lines in the image, then the number of pulses making up the scan is 100.
True
True or False.
If 100 scan lines make up an image and the frame rate is 30 per second, then then transducer's frequency is 3000 Hz.
False.
they are unrelated
True or False.
If 100 scan lines make up an image and the frame rate is 30 per second, then the system's pulse repetition frequency is 3000 Hz.
True
When the frame rate is 30 Hz, how long does it take to create a frame?
1/30 sec
Under certain conditions, an ultrasound system creates each image in 0.01 seconds. What is the frame rate?
