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
You may see reverberation when
Imaging the pleura or when you’re using a highly attenuating wide bore needle
Common ultrasound artifacts include
Air, shadow, acoustic enhancement, mirror image, reverberation, bayoneting
Air artifact appears as
A black region
Air artifact is solved by
Applying more gel, applying more pressure, or selecting a transducer with a footprint that allows for better contact
Because acoustic energy doesn’t penetrate bone very well, you’ll observe ________ deep to the hyperechoic border
Acoustic shadow
_____________ is the best way to minimize the influence of a shadow artifact
Adjusting the scanning plane to find a better acoustic window
______ occurs when the US beam gets trapped between two highly reflective tissues and this causes a time delay in some of the returning echoes
Mirror image
________ occurs when the needle passes through the adjacent tissues of different acoustic impedance
Bayoneting
Bayoneting appears like
The needle bending as it penetrates a tissue boundary
During a cardiac POCUS examination, what structures are visible on a parasternal short-axis view of the heart?
Right ventricle
Aorta
Left ventricle
Pericardium
Left ventricle & pericardium
The basic cardiac exam relies on three standard imaging windows including
Parasternal
Apical
Subcostal
The basic cardiac exam consists of five views
Parasternal long-axis
Parasternal short-axis
4 chamber apical
4 chamber subcostal
IVC
Cardiac POCUS allows us to answer yes/no questions about the patient’s clinical status including
Is there ventricular function failure, valvular dysfunction, pericardial effusion, patient’s volume status, regional wall motion abnormalities, responsiveness to fluids, are there gross signs of chronic hear disease, is there an inter cardiac mass
In the parasternal window we can view the
Parasternal long axis & parasternal short axis
In the apical window we can view
An apical 4 chamber
In the subcostal window we can view
Subcostal 4 chamber & subcostal IVC
Structures viewed in the parasternal long axis include
LA, LV, mitral valve, aortic valve, aorta, pericardium
The parasternal long axis view can be utilized to interpret
LV function, aortic and mitral valve lesions, and pericardial effusions
In the parasternal short axis we can view the structures of the
LV+ papillary muscle, RV, and pericardium
In the parasternal short axis view, we can use this to interpret
LV and RV function, pericardial effusion
In the apical 4-chamber view, structures visualized include
RA, RV, LV, LA, mitral valve, aortic valve, pericardium
The apical 4 chamber view can be utilized to interpret
LV and RV function , AV valve lesions, pericardial effusion
The subcostal 4 chamber view can be utilized to visualize
RA, RV, LV,LA, mitral and aortic valves, liver
The subcostal 4 chamber view can be used to interpret
RV function. Pericardial effusion
The structures visualized in the subcostal IVC include
IVC, RA, and liver
The subcostal IVC can be used to interpret
Volume status
IVC collapse suggests
Hypovolemia
Lung US is useful for diagnosing
Pneumothorax and endobroncheal intubation
Gastric contents are best assessed with ultrasound when the patient is in the _______ position
right lateral decubitus
Performing gastric ultrasound in the supine position will
likely underestimate the volume of gastric contents
If the stomach is empty, the antrum will appear
flat or like a small oval, sometimes referred to as a “bull’s eye”
Clear contents inside the stomach will make the antrum look
round and distended
clear liquids will be anechoic
Particulate matter inside the stomach will make the antrum look
round and distended and appear hyperechoic or bright particulate matter
