Chapter 14 Flashcards
What are the 6 components of an ultrasound system
Transducer, pulser and beam former, receiver, display, storage and master synchronizer
What is the function of the pulser
Creates electrical voltage that excites PZT
Strong voltage produces a ______ image
Better. (Strong pulse= strong ringing, strong reflection, brighter image)
Is the pulser’s output adjustable
Yes
Noise is always _______
Consistent
What is the function of the master synchronizer
Organizes the interaction of the systems components. Dirige el tráfico basically
The beam former operates in both transmission and _______
Reception
What is apodization
Reduction of lobe artifacts
What is the switch
Esto es lo que decide si la máquina está en transmit mode or receive mode
What is the receiver function
Process voltages and gets them ready for display
List the receiver operations in the correct order
Amplification
Compensation
Compression
Demodulation
Rejection
What are other names for pulser voltage
Output gain, acoustic power, transmitter output, energy output
Amplification is also known as
Receiver gain
Is amplification adjustable
Yes
Pre amplification occurs within the
Transducer
Describe the amplification process
All signals are made larger EQUALLY. it doesn’t improve signal to noise ratio
Compensation is also known as
Time-gain compensation (TGC)
Is compensation adjustable?
DUH. Son los TGCs
What does compensation do
Creates an image that is uniformly bright top to bottom
List the names of the sections of the TGCs buttons
From top to bottom:
near gain (small compensation) delay (variable compensation begins)
slope (variable)
knee (almost all the compensation)
and far gain (maximum compensation)
Compression is also known as
Dynamic range
Is compression adjustable
Yes
What is the function of compression
Keep the range of greys compressed so the human eye can see them
Demodulation is also known as
Detection
Is demodulation adjustable
NO
What are the two steps of demodulation
Rectification, and smoothing
What is rectification
Converting negative voltages into positive ones
What is smoothing
Placing smooth lines around the bumps of the different voltages to kind of make them one
Rejection is also known as
Threshold or suppression
Is rejection adjustable
Yes
What is rejection
Getting rid of low level echoes que no sirven y hacen ver la imagen grainy
What is dynamic frequency tuning
Una tecnología que usa high frequency to create superficial portion of the image and low frequency for deeper portion
What does ALARA stand for and what’s the meaning
AS LOW AS REASONABLY ACHIEVABLE
It means we should lower the output power that we can possibly use to get the image
When modifying output power or receiver gain the first option is gonna be the one that protects the
Patient. (Always lowering output power first)
