Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Emergency Medicine > Ultrasound > Flashcards

Ultrasound Flashcards

1
Q

What is the frequency of medical US?

A

2-20 milllion Hz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the transducer?

A

Contains piezo-electric crystal

Converts energy from electrical to acoustic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What frequencies do transducers come in + what are they good for?

A

High (7-18) - high resolution but low depth, good for superficial vessels

Low (2-6) - penetrate deeper but lower resolution eg abdo + obstetric

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is acoustic impedence?

A

Property of each tissue - depends on density + speed of sound waves passing through it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is shadowing?

A

Calcium is a strong reflector so causes shadowing posteriorly (eg in gallstones)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What do vessels, bones, soft tissue, nerves + muscle look like + what terminology do we use to describe it?

A

Vessels - black - anechoic

Bones - white - hyperechoic

Soft tissue - grey - isoechoic

Nerves - honeycomb - hypo/hyperechoic

Muscle - gray - isoechoic with white strands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How to alter depth + why

A

Start with high depth then decrease to put area of interest around 3/4 of screen depth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is gain compensation?

A

Selectively amplifying echoes from deep tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are calipers used for?

A

Allows measures to be made

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the commonly seen artefacts?

A

Shadowing

Acoustic enhancement

Reverberation

Comet tail

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is shadowing?

A

Strong reflective region of calcium that reduce energy remaining in beam distal to it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is acoustic enhancement?

A

Occurs when sound waves pass through low acoustic impedance to normal acoustic impedance

Occurs in vessels, bladder, cysts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is reverberation?

A

Large echo created by strong reflector - bounces back after hitting probe

Continues to bounce back and forth giving impression of multiple lines - equally spaces + gradually losing brightness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is a comet tail artefact?

A

multiple reflections occur within small strongly reflecting object

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is a FAST scan?

A

Focussed assessment with sonography for trauma

Checks for fluid/ air in pericardial, peritoneal + pleural cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Where are the probes placed in a FAST scan?

A

Subcostal cardiac

RUQ

LUQ

Pelvis

17
Q

What is static vs dynamic US access?

A

Static = mapping

Dynamic = views needle in real time

18
Q

How to US aorta

A

Put probe transverse across body

Push down to move bowel, aorta will appear cross sectionally, verterbra posteriorly

Measure using calipers the diameter

Turn probe longitudinally to measure diameter again

Transverse, measure down to the bifurcation

Emergency Medicine (24 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions