Ultrasound 2 Flashcards
Which setting on the US machine is used to adjust the strength of the returning echoes displayed on the screen?
A. Depth
B. Attenuation
C. Gain
D. M mode
C. Gain
_______ determines how deeply you can see into the body
Depth
_______ produces a real-time image of the sonoanatomy and most bedside US procedures utilize this modality.
B mode
The “B” in b-mode stands for the
Brightness of the pixels on the screen
M-mode stands for ______ and is an alternative US modality similar to a time-lapse photo, it illustrates the reflective movement of structures over time
Motion
According to the Doppler effect, what changes occur when the sound source moves closer to a person listening to that sound?
1. Wavelength becomes shorter
2. Pitch increases
3. Doppler shift becomes negative
- & 2.
If the source moves towards an observer, then the wavelength gets _______ in this direction, and the frequency (pitch) appears to _______. We call this a _______ Doppler effect.
Shorter, increase, positive
The Doppler effect describes the change in the
Perceived frequency of a sound wave when there’s relative motion between the sound’s source and an observer
In terms of ultrasound, a positive Doppler shift appears _____, and a negative Doppler appears
Red; blue
When evaluating the Doppler shift, you must understand the
Angle of insonation
The degree of Doppler shift depends on
Frequency of the US beam
Blood flow velocity
Angle of intonation
According to the standard convention, the orientation marker on the US probe should point towards
The head of the right
This breaks the standard convention of having the orientation marker on the right
Cardiology convention
The _________ describes the angle at which the US waves encounter a structure.
The angle of incidence
You’ll obtain the best image quality when the US beam encounters a structure at
90 degrees
Describe in plane vs out of plane
In-plane: needle runs parallel to the transducer, long axis of the needle
Out- of plane- perpendicular, short axis of the needle
Describe tilting.
Moving the probe backward and forward at the same point of contact to changes the angle of incidence
Describe rocking.
Moving the transducer from side to side while in the long axis
Helpful while viewing a narrow acoustic window
Describe compression.
Improves image resolution by reducing the distance between the probe and the image
Describe sliding.
Moving the transducer up and down while maintaining the sample angle of incidence
Describe rotation.
Moving the transducer in a clockwise or counter clock-wise fashion in the same axis of compression; helpful when changing from long to short axis
What is reverberation?
Occurs when a sound wave bounces between two strong parallel reflecting surfaces