oral Resolution
Pulse Echo Instrumentation
Q1. Name the components of an ultrasound system?
Answer:
The components of an ultrasound system are trans
... [Show More]ducer, pulsar, receiver, scan
converter, display, and master synchronizer.
Q2. What is the Master Synchronizer?
Answer:
Master Synchronizer is a component of ultrasound machine which maintains and organizes the proper timing and interaction of all components of the ultrasound
machine so that ultrasound system can operate as a single integrated system.
Q3. What is an ultrasound transducer?
Answer:
The ultrasound transducer is a part of ultrasound machine. It contains a piezoelectric material which converts electrical energy into acoustic energy during the transmission phase, and converts acoustic energy into electrical energy when the
echoes return to the transducer after traveling in the body during reception phase.
Q4. What is Channel?
Answer:
A channel in ultrasound system consists of a single crystal, the beam former, pulsar
electronics, and the wire connecting them.
Q5. What is a receive channel?
Answer:
Each active element in an ultrasound transducer is connected to an amplifier and processing chain. The amplifier and processing chain are collectively known as the
receive channel. There are 256-512 active receive channels are present in ultrasound systems. The benefits of more receive channels in ultrasound systems is greater
processing flexibility.
Q6. What is Switch?
Answer:
Switch in ultrasound system protects the delicate receiver components from the high voltage signals created during pulse creation. It directs low voltage signals from the
transducer to the appropriate processing components within the system.
Q7. What is interpolation?
Answer:
Fill in Interpolation is a technique in which made up pixels are used to fill the areas
between the scan lines where there is no information available.
Q8. What is frequency compounding?
Answer:
Frequency compounding is the technique of imaging with multiple frequencies and
averaging them out. Frequency Compounding improves contrast resolution and
reduces speckle which improves the image quality.
Q9. What is Dynamic Frequency Tuning?
Answer:
Dynamic frequency tuning is a technique in which high frequency portion of the
ultrasound pulse is used to create images from the shallow depths, and the low
frequency portion of the ultrasound pulse is used to create the images from the
greater depths.
Q10. All of the following are components of an ultrasound system except?
1. transducer
2. pulsar
3. alternator
4. synchronizer
5. display
6. receiver
Answer: c. alternator
Alternator is not the component of the ultrasound machine.
Output Power
Q11. What does the output power control?
Answer:
Output power is the amount of voltage applied to the piezoelectric element to produce an ultrasound pulse. Output power controls the amplitude of the voltage that
excites the piezoelectric crystals.
Q12. What is the relationship between pulsar voltage and the returning echo strength and increasing pulsar voltage will have what effect on the image?
Answer:
There is a direct relationship between pulsar voltage and the returning echo strength.
By increasing the pulsar voltage increases the strength of the returning echo signal
and increases the brightness of the image.
Q13. What is the range of pulsar output voltage which excites a piezoelectric crystal in the ultrasound transducer?
Answer:
The strength of pulsar output voltage that excites the piezoelectric crystals ranges
from 1-300 volts and lasts less than 1 microsecond.
Q14. What is the range of input voltage signal to the receiver of an ultrasound system?
Answer:
The signal produced by the transducer upon receiving the returned echoes and sent to
the receiver of the ultrasound system is extremely small and is in the micro volt to
milli volt range.
Q15. What determines the strength or intensity of the ultrasound wave?
Answer:
The output power generated by pulsar determines the strength or intensity of the ultrasound wave produced by the transducer. The greater the strength of electrical signal from the pulsar that excites the piezoelectric crystal, the greater the intensity of
the ultrasound wave produced.
Q16. Can sonographer change the output power? [Show Less]