CPSS -- POCUS EXAM QUESTIONS AND ANSWERS
What colour will "Anechoic" appear as on US?
What about "Hyperechoic"?
Anechoic: Black; Poor reflectors --> Fluid
Hyperechoic: White; Strong reflectors --> Inflammation/solid masses
Note: -Mixed reflectors appear as grey
-Gas gives a "Snow like" appearance
What are the soundwaves in hertz associated with:
1. Infrasound
2. Audible frequencies
3. Ultrasound
1. Infrasound: <16 Hz
2. Audible frequencies: 16 Hz - 20 kHz
,3. Ultrasound: >20 kHz (normally in the mega-Hz though, so real high)
What is the following parts of a sound wave:
1. Frequency
2. Wavelength
3. Compression
4. Rarefaction
5. Period
1. Frequency (f): -Inverse to wavelength (no of wavelengths in given quantity of time)
2. Wavelength (λ): -Inverse to frequency
-Distance between 2 compressions'/rarefactions' (1 oscillation)
-Wavelength =Velocity/frq
3. Compression: Top of a wave
4. Rarefaction: Bottom of a wave
5. Period (T): Time between 2 compressions/rarefactions
, What is the following probes:
1. Linear probes
2. Curvilinear probes
3. Phased array probes
1. Linear probes: 5MHz-10MHz; Shorter wavelength but high frequency -- allows good
superficial resolution, but poor penetration
2. Curvilinear probes: 1MHz-5MHz; Wider wavelengths and lower frequencies -- allows
good penetration but the resolution is less sharp
3. Phased array probes: 1MHz-5MHz; Wider wavelengths and lower frequencies --
allows good penetration but the resolution is less sharp
Notes: -Linear is good for superficial structures and soft tissues; Curvilinear and phased
array are good for deep structures or obese pts.
-Only the linear and phased array transducers can be used for the orbits.
Define the following in terms of US:
What colour will "Anechoic" appear as on US?
What about "Hyperechoic"?
Anechoic: Black; Poor reflectors --> Fluid
Hyperechoic: White; Strong reflectors --> Inflammation/solid masses
Note: -Mixed reflectors appear as grey
-Gas gives a "Snow like" appearance
What are the soundwaves in hertz associated with:
1. Infrasound
2. Audible frequencies
3. Ultrasound
1. Infrasound: <16 Hz
2. Audible frequencies: 16 Hz - 20 kHz
,3. Ultrasound: >20 kHz (normally in the mega-Hz though, so real high)
What is the following parts of a sound wave:
1. Frequency
2. Wavelength
3. Compression
4. Rarefaction
5. Period
1. Frequency (f): -Inverse to wavelength (no of wavelengths in given quantity of time)
2. Wavelength (λ): -Inverse to frequency
-Distance between 2 compressions'/rarefactions' (1 oscillation)
-Wavelength =Velocity/frq
3. Compression: Top of a wave
4. Rarefaction: Bottom of a wave
5. Period (T): Time between 2 compressions/rarefactions
, What is the following probes:
1. Linear probes
2. Curvilinear probes
3. Phased array probes
1. Linear probes: 5MHz-10MHz; Shorter wavelength but high frequency -- allows good
superficial resolution, but poor penetration
2. Curvilinear probes: 1MHz-5MHz; Wider wavelengths and lower frequencies -- allows
good penetration but the resolution is less sharp
3. Phased array probes: 1MHz-5MHz; Wider wavelengths and lower frequencies --
allows good penetration but the resolution is less sharp
Notes: -Linear is good for superficial structures and soft tissues; Curvilinear and phased
array are good for deep structures or obese pts.
-Only the linear and phased array transducers can be used for the orbits.
Define the following in terms of US: