Image Modalities And Insrumentation

Question 1

What does M mode represent?

Answer 1

The movement of structures over time.

Question 2

What does color Doppler use to show color patterns?
- what color is towards the transducer?
- what color is away from the transducer?

Answer 2

Measurement of velocity and direction of blood
- red
- blue

Question 3

What is Pulse wave doppler?

Answer 3

Doppler used to take localized velocity measurement

Question 4

When do you see aliasing?

Answer 4

In pulse wave
- happens when Doppler shift exceeds 1/2 of the PRF

Question 5

Continuous wave Doppler uses 2 side by side elements what does each do?

Answer 5

• one continuously sends transmits while the other continuously receives

Question 6

What kind of velocity do you see with CW?

Answer 6

Maximum velocities ; samples all blood flow in its path

Question 7

What is fhe advantage of CW?
What is the disadvantage of CW?

Answer 7

• no aliasing
• does not get specific velocity at a specific location

Question 8

What does TDI measure?

Answer 8

Velocity of the myocardium

Question 9

TDI only measures the vector or motion _______ to the direction of the sound beam.

Answer 9

Parallel

Question 10

What does myocardial strain refer to?

Answer 10

The deformation of the myocardium through the cardiac cycle

Question 11

Positive strain for myocardial strain shows what about the fibers?

Answer 11

Lengthening and thickening

Question 12

Negative strain for myocardial strain shows what about the fibers?

Answer 12

Shortening and thinning

Question 13

Myocardial Strain parameters what are they and what are their planes?

Answer 13

• velocities , strain and strain rate
• x , y , z directions

Question 14

Myocardial strain is used as marker of myocardial function to detect changes in the ———

Answer 14

Regional function

Question 15

What does contrast do to the heart?

Answer 15

It fills the left side of the heart to enhance the LV endocardial border

Question 16

What is a spontaneous echo contrast?
- what is it due to?

Answer 16

A swirling pattern seen in the left atrium.
- due to MS and A-FIB

Question 17

What 4 steps are involved in creating a 3D ultrasound ?

Answer 17

• data acquisition
• data storage
• data processing
• image display

Question 18

What does 3D data acquisition do?

Answer 18

Obtains echo characteristics of many single points within a volume tissue

Question 19

What does 3D data storage do?

Answer 19

Maintains data flow from the initial raw data acquisition to the next step of data processing

Question 20

What does 3D data processing consists of? (What 2 steps?)

Answer 20

• conversion
• interpolation
  These transform the scanned raw date for a specific volume into a 3D data used to create a 3D object

Question 21

What are the 2 usefulness of 3D echo ?

Answer 21

• direct tabulation of cardiac chamber volumes. Resulting in more accurate LV volume and EF
• new surgical views of cardiac valves structures and masses

Question 22

What does a transducer convert electrical energy into?

Answer 22

Mechanical energy (sound) and back again

Question 23

With a higher frequency what kind of resolution and penetration do you get?

Answer 23

• high resolution
• poor (shallower) penetration

Question 24

With low frequency what kind of resolution and penetration do you get?

Answer 24

• poor resolution
• deeper penetration

Question 25

What is output power?

Answer 25

Determines the energy transmitted by the transducer

Question 26

What does TGC stand for? And what does it do?

Answer 26

- time gain compensation - allows adjusting gain setting in different depths to compensate for attenuation

Question 27

What is frequency directly related to ? Inversely related to?

Answer 27

- Spatial resolution - penetration

Question 28

What is temporal resolution?

Answer 28

The ability to accurately pinpoint an objects location at a specific moment in time

Question 29

Wide sector width give better over view of cardiac structures, by decreasing the sector width what happens to the frame rate and temporal resolution?

Answer 29

Frame rate will increase Causing temporal resolution to increase

Question 30

Describe the depth knob on the machine?

Answer 30

It adjusts the depth from which the returning ultrasound signals will be displayed

Question 31

The deeper the depth the slower the ——— of an image

Answer 31

Frame rate

Question 32

Frame rate determine what?

Answer 32

Temporal resolution

Question 33

What is PRF?

Answer 33

Pulse repetition frequency is the number of times that a pulse is repeatedly SENT during ONE SECOND

Question 34

Flow towards the transducer is ____ the spectral Doppler baseline

Answer 34

Above

Question 35

Flow away from the transducer is _____ the spectral Doppler baseline

Answer 35

Below

Question 36

What does post processing do? - is it operator controllable

Answer 36

- “the reading of the writing (pre)” Manipulates data after it has been stored it can convert prior to display - yes

Question 37

What is pre processing?

Answer 37

- “the writing down of the info” Manipulation of scan date before storage in the memory after scan conversion

Question 38

More pixels =

Answer 38

Better spatial resolution

Question 39

What is pixel interpolation (preprocessing)

Answer 39

A way of filling in gaps of days undetected by the observer

Question 40

The transducer emits waves and travels in what kind of like?

Answer 40

Straight line

Question 41

What is attenuation?

Answer 41

Loss of energy as it travels through a medium

Question 42

What is the speed of sounds through soft tissue ?

Answer 42

1540 m/s

Question 43

Too much gain can create what?

Answer 43

A mosaic distribution of color signals throughout the image

Question 44

What is reverberation?

Answer 44

Is when US beam encounters 2 strong parallel factors When US beam delete back and forth between the reflectors. Takes longer for the wave to return back to the transducer

Question 45

Is a comet tail artifact a type of reverberation?

Answer 45

Yes

Question 46

Why does shadowing occur?

Answer 46

Due to anatomy located directly behind the strongly attenuating prefecture will appear as drop out

Question 47

When does mirror image artifact occur?

Answer 47

When there is a highly reflective surface (diaphragm) in the path of the primary beam

Question 48

When does aliasing occur?

Answer 48

When mean velocities of flow increase behind the nyquist limit