Doppler

Question 1

Maximum flow is when the Doppler beam is?

A) parallel to flow
B) perpendicular to flow
C) oblique to flow
D)unattainable

Answer 1

A) parallel to flow

Question 2

What is range resolution?

Answer 2

The ability to distinguish between two objects

Question 3

Which Doppler has range resolution, pulse wave or continuous wave?

Answer 3

PW

Question 4

Which Doppler has a limit on the maximum velocity pulse wave or continuous wave?

Answer 4

PW

Question 5

What is the Doppler equation?

Answer 5

V= c / /cos sine x f2

Question 6

Which valve lesion has the highest Doppler peak?

A) TR
B) MR
C) AI
D) PI

Answer 6

B) MR

Question 7

What’s a typical gradient for AS?

A) 1.0-1.6 m/sec
B) 2.0-3.0 m/sec
C) 3.0-5.0 m/sec
D) 1.6-2.0 msec

Answer 7

C) 3.0-5.0 m/sec

Question 8

Laminar flow is ?

A) irregular
B) smooth
C) shaggy
D) jagged

Answer 8

C) smooth

Question 9

With laminar flow, where is the area of highest velocity?

Answer 9

The center

Question 10

Smooth flow in the same direction is called?

Answer 10

Laminar or parabolic

Question 11

What kind of flow is bullet shaped?

Answer 11

Laminar/ parabolic

Question 12

What flow is “bullet shaped?”

Answer 12

Laminar/parabolic

Question 13

What flow creates vortices?

Answer 13

Turbulent flow

Question 14

Turbulent flow has blood cells that move in ____ directions with ___ velocities

Answer 14

Different ; varying

Question 15

What are 4 factors that affect blood flow?

Answer 15

Pressure
Length of vessel
Diameter of vessel
Blood viscosity

Question 16

The longer the vessel the greater the?

Answer 16

Resistance

(because the longer the vessel the more it resistance it needs to push blood through it)

Question 17

The smaller diameter of the vessel the greater the?

Answer 17

Resistance

(the smaller the space the more resistance required to pass through)

Question 18

High viscosity means high ___ and low___

Answer 18

Resistance ; velocity

Question 19

The lower the viscosity the lower the ____ and higher ___

Answer 19

Resistance ; velocity

Question 20

What is ghosting in color Doppler?

Answer 20

Flashes of color caused by moving from atomic structures and not blood flow

Question 21

What would you do to prevent ghosting?

A) increase gain
B) roll the patient
C) increase water filter
D) decrease sector size

Answer 21

C) increase wall filter because the flashes are low velocity