Lesson 1 (Part 1) Flashcards
What are 2 types of diagnostic ultrasound?
- Grey scale ultrasound
2. Doppler ultrasound
What is an example of grey scale U/S?
Pulse echo technique
What is an example of doppler U/S?
Pulse echo + doppler
What does sono mean?
Sound
What does graph mean?
To write
What does the brightness of the echo determine?
The echo strength
- depends on the reflector
What are 2 other names for grey scale U/S?
- 2D imaging
2. B mode
What does B mode mean?
Brightness
Why do we hear explosions after the fact?
Light travels faster than sound
What is the source of all sound?
Vibrations
What medium does sound travel faster in?
Solids
Can sound travel through a vacuum?
No
- a medium is required
What is loudness measured in?
Decibels
What happens to the pitch if frequency is increased?
It increases
If you heard something loud through the wall, what would you hear?
Low pitch sounds
What makes a sound louder or quieter?
Wave amplitude
What happens to the sound when you have a large amplitude?
You get a large sound
What happens to the sound when you have a small amplitude?
You get a quieter sound
What type of wave is sound?
Mechanical
What are 2 examples of electromagnetic waves?
- Radio waves
2. X-rays
What range of frequencies can humans hear?
20Hz - 20,000Hz
Is light a mechanical wave?
No
How does an ultrasound work? (4)
- Send a pulse through the transducer
- It goes out and hits something (like an organ)
- Reflects back
- Creates an echo
What does it mean when you have a bright echo?
You have hit a strong structure
-eg) bone, diaphragm, Ca structures
How will fluid appear in an echo?
Anechoic
- black
What are 3 common sonographic scan formats?
- Linear
- Sector
- Combination of the two
- linear and sector
What is the formula for distance?
Speed x Time
What is the formula for time?
Distance / Speed
What is the formula for Speed?
Distance / Time
