Pulse-Echo Instrumentation Flashcards
(181 cards)
What system control should you adjust to compensate for sound attenuation with increasing depth? A. Dynamic range B. TGC C. Transmit power D. Overall receiver gain E. Focus position
B. TGC
What system control determines the amount of amplification that occurs in the receiver? A. Gain B. Acoustic power output C. Rectification D. Pulse repetition frequency E. Dynamic range
A. Gain
When you adjust the output power control , you affect the following system component: A. Pulser B. Beam former C. Scan converter D. Memory
A. Pulser
What system control do you adjust to equalize the differences in echo amplitudes received from similar structures situated at different depths? A. Dynamic range of compression B. Rectification C. Time gain compensation D. Pulse repetition frequency
C. Time gain compensation
Electronic noise is reduced in the ultrasound system by this method: A. Demodulation B. Compensation C. Rectification D. Amplification E. Rejection
E. Rejection
You have chosen to enlarge an ultrasound image with a read magnification. Which of the following is NOT related to read magnification? A. Preprocessing B. Increased pixel size C. Performance on a frozen image D. Resolution loss E. B and D only
A. Preprocessing
What term below describes the rate at which the transmitter applies electronic voltage pulses to the transducer? A. Period B. Pulse repetition frequency C. Depth gain compensation D. Demodulation
B. Pulse repetition frequency
Pulsing of the transmitted sound wave is necessary for real -time imaging because :
A. The transducer becomes too hot to handle if continuous sound waves are emitted
B. The crystal in the transducer will break under the stress of continuous emissions
C. The depth of the interface from which the echo originated can be determined
D. Lateral resolution is improved by pulsed transmission
C. The depth of the interface from which the echo originated can be determined
What receiver function is responsible for decreasing the difference between the smallest and the largest received signal and amplitudes? A. Amplification B. Compensation C. Compression D. Demodulation E. Rejection
C. Compression
What receiver function listed below is NOT operated -adjustable ? A. Amplification B. Compensation C. Demodulation D. Rejection E. A and D
C. Demodulation
While performing a sonographic exam, you have performed both preprocessing and post processing functions. Which of the following functions is post processing ? A. Write-zoom magnification B. Frequency change C. Gray-scale map assignment D. Scan line density
C. Gray-scale map assignment
Which of the following would be most helpful to enhance the contrast difference between tissues having subtle variations in echogenicity ?
A. Decreasing the acoustic power output
B. Decreasing the scan line density
C. Performing a read-zoom magnification over the area of interest
D. Changing the gray-scale map assignment
D. Changing the gray-scale map assignment
What part of the sonographic instrument is responsible for apodization, beam steering , focusing, and aperture control? A. Beam former B. Receiver C. Memory D. Pulser
A. Beam former
What control should you adjust to better compensate for the attenuation of sound as it propagates through tissue? A. Dynamic range B. Time gain compensation C. Acoustic power output D. Rejection
B. Time gain compensation
Which control would you adjust to increase the intensity of the transmitted pulse? A. Receiver gain B. Depth of scanning C. Output power D. Time gain compensation
C. Output power
Which control would you adjust to alter the dynamic range of the displayed echoes? A. Compensation B. Transmit power C. Scanning depth D. Time gain compensation
A. Compensation
The technique of frame averaging (persistence) during real-time acquisition is designed to : A. Reduce random noise B. Decrease pixel size C. Redistribute the gray scale D. Enhance spatial resolution E. Increase frame rate
A. Reduce random noise
You are performing a sonographic exam and select the tissue harmonics operating mode. What advantage will you obtain over conventional imaging? A. Improved contrast resolution B. Improved penetration C. Improved temporal resolution D. Improved signal-to-noise ratio
A. Improved contrast resolution
You have decreased the scan line density. What technique will be employed to fill in the empty data between the scan lines? A. Interpolation B. Rejection C. Compression D. Autocorrelation E. Demodulation
A. Interpolation
While performing an ultrasound examination, you decide to adjust the system settings to improve the image. Which of the following is NOT user-adjustable? A. Frequency B. Power C. Gain D. Compensation E. Echo arrival time
E. Echo arrival time
What control should you adjust to optimize the image of you are scanning a structure that produces very bright echoes on the display? A. Rejection B. TGC C. Edge enhancement D. Frame averaging
B. TGC
To generate a sonographic image, what is the order in which the following system components are activated?
A. Pulser, receiver , display , beam former, memory
B. Pulser, beam former, receiver , memory , display
C. Beam former , pulser , memory , display , receiver
D. Memory , beam former, pulser , receiver, display
B. Pulser, beam former, receiver , memory , display
What is a typical frame rate for B-mode real time imaging ? A. 1-9 kHz B. 10-50Hz C. 100-200 MHz D. 200-300 Hz
B. 10-50Hz
What control could you adjust to improve the signal -to -noise ratio on the image? A. Dynamic range B. Frame averaging C. Gray-scale map D. Edge enhancement
B. Frame averaging