Vascular Doppler Test 1

Question 0

What are the different modes to combine together?

Answer 0

2D

gray scale

B-mode

plus:

color doppler
pulsed doppler - spectral doppler

Question 1

What is duplex imaging?

Answer 1

integrating different forms of Doppler

Question 2

What is flow analysis?

Answer 2

is there flow?

the presence or absence of flow

Question 3

how do you determine Portal vein?

Answer 3

echogenic wall

traverses across the liver - hepatic veins go up into the liver

Question 4

What is important about the doppler curser?

Answer 4

called the gate or sample volume

proper placement is important

in the center of the vessel

Question 5

How do you tell the direction of flow?

Answer 5

color map

above the black line = toward the transducer red

below black line = away from the transducer blue

Question 6

what does hepatopetal mean?

Answer 6

toward the liver

this is the way you want to the blood to flow

Question 7

what does hepatofugal mean?

Answer 7

away from the liver

this is the wrong way for the blood to flow

Question 8

What is spectral display low flow?

Answer 8

Non resistive - low

high diastolic

constant perfusion

Question 9

what is spectral display high flow?

Answer 9

Resistive - high

little diastolic or reversed flow

Question 10

What is spectral display?

Answer 10

time (on the x axis)

Doppler shift frequency is on the vertical y - axis

gray scale quanitity of blood (z)

Question 11

What is the computer computing with spectral display?

Answer 11

Doppler frequency shift measured in Hz

the machine changes it to speed

Question 12

what is the pulsatility index (PI)?

Answer 12

a measure of the variability of blood velocity in a vessel, equal to the difference between the peak systolic and minimum diastolic velocities divided by the mean velocity during the cardiac cycle.

Question 13

What is plug flow?

Answer 13

pattern of blood flow, typically seen in large arteries, in which most cells are moving at the same velocity across the entire diameter of the vessel

Question 14

What is turbulent laminar flow?

Answer 14

Abnormal

chaotic patterns

Question 15

What are some techniques for using Doppler?

Answer 15

fasting

suspend respirations

parallel to flow 0 degrees

angle less than 60 degrees

Question 16

What changes about the SMA after you eat concerning Doppler?

Answer 16

high resistance before

low resistance after

see slides for visual

Question 17

What is RAS?

Answer 17

renal artery stenosis

Question 18

what is tardis parvis?

Answer 18

when you lose the point on the doppler wave

Question 19

Where would you find non resistive low flow confirmed by spectral display?

Answer 19

internal carotid,

hepatic

renal

Question 20

Where do you find resistive high flow confirmed by spectral doppler?

Answer 20

supply to organs that do not need constant blood supply

external carotid

iliac

brachial arteries

Question 21

How is blood velocity calculated?

Answer 21

by frequency shifts

Question 22

How do you read a spectral display?

Answer 22

The peak is the systolic and the end is the diastolic

Question 23

What is the formula for the resistive index?

Answer 23

RI = Peak systolic velocity - lowest diastolic velocity/ peak systolic velocity

RI = S-D/S

Question 24

What is resistive index?

Answer 24

peak systole is compared with minimum diastole to quantify a vessels impedance

Question 25

What picture does typical plug flow give you on the spectral doppler?

Answer 25

a "clear window" under systole

Question 26

What needs to be present for the volume of blood flow to be calculated?

Answer 26

plug flow must be present

Question 27

What is parabolic flow?

Answer 27

velocity higher in the center of the laminar layers and decreases at the vessel wall

Question 28

What are the doppler flow patterns for the Aorta?

Answer 28

High systolic peak varies at different levels becomes triphasic closer to the legs

Question 29

What does triphasic mean?

Answer 29

having or occurring in three phases...seen and heard

Question 30

What is the Doppler flow pattern of the celiac axis?

Answer 30

Some spectral broadening no change related to meals

Question 31

what is spectral broadening?

Answer 31

broadening of the spectral lines (makes them thicker)

Question 32

What are the doppler flow patterns for the hepatic artery?

Answer 32

more spectral broadening is seen during systole and diastole

Question 33

What are the doppler flow patterns in the splenic artery?

Answer 33

turbulence prone to aneurysm

Question 34

What are the Doppler flow patterns in the SMA?

Answer 34

highly resistive in the fasting state low resistive in the post prandial state SMA occulsion is possible

Question 35

What are the Doppler flow patterns for the Renal arteries?

Answer 35

Low resistive high diastolic flow spectral broadening renal artery stenosis possible

Question 36

What is the doppler flow pattern in renal artery disease?

Answer 36

high velocity jet shown in the right renal artery spectral waveform shows increased velocity of more than 4 m/sec

Question 37

How do you improve color images?

Answer 37

increase the PRF or scale

Question 38

What can cause aliasing of the spectral waveform?

Answer 38

if the frequency shift is too high for the PRF setting

Question 39

What does aliasing of the spectral waveform mean?

Answer 39

a portion of the waveform is cut off and displayed below the baseline

Question 40

How do you fix aliasing of the spectral waveform?

Answer 40

by raising the PRF and lowering the baseline this allows the peak velocity to display correctly and an accurate velocity to be obtained

Question 41

What does Power Doppler NOT demonstrate?

Answer 41

Direction of flow

Question 42

What are the doppler flow patterns for a renal transplant?

Answer 42

normal transplants have a diastolic flow that is 30-50% of systole

Question 43

what does rejection of a transplanted kidney do to the doppler flow patterns?

Answer 43

decreases or reverses the diastolic flow

Question 44

What does an RI of 0.7 or less indicate in a renal transplant??

Answer 44

indicates good perfusion

Question 45

What does an RI of 0.7-0.9 indicate in a renal transplant?

Answer 45

possible rejection

Question 46

What does and RI of 0.9 or greater indicate in a renal transplant?

Answer 46

indicates probable rejection

Question 47

What is the Doppler flow pattern in the Renal Vein?

Answer 47

variable flow tumors make obstructive flow

Question 48

What pathology could you possibly have if you have a complex waveform in the hepatic veins?

Answer 48

could be reflecting reflux from the right atrium

Question 49

What kind of flow pattern does the Portal vein have?

Answer 49

continuous flow pattern hepatopetal (toward the liver)

Question 50

What might cause HTN in the portal vein?

Answer 50

intrinsic liver disease obstruction

Question 51

what is Budd Chiari?

Answer 51

Thrombosis of the hepatic veins veins appear reduced in size may contain echogenic thrombus

Question 52

What are some things you might find with portal vein hypertension?

Answer 52

Dilated portal, splenic and SMV varices Splenomegaly Ascites patent umbilical vein abnormal liver

Question 53

What happens to the portal vein's response to respiration when there is portal vein hypertension?

Answer 53

there is a diminished response

Question 54

What does portal vein hypertension do to the hepatic and splenic arteries?

Answer 54

it dilates them

Question 55

What is the definition of Portal Hypertension?

Answer 55

acute or chronic hepatocellualr disease can block the flow of blood throughout the liver, causing it to back up into the hepatic portal circulation. This causes the blood pressure in the hepatic circulation to increase

Question 56

When and why do collateral veins form?

Answer 56

when there is portal hypertension, collateral veins are formed in an effort to relieve the pressure. they connect to the systemic veins

Question 57

Where do most collateral (varicose) veins occur?

Answer 57

in the esophagus stomach rectum

Question 58

What happens if varicose veins in the esophagus, stomach or rectum rupture?

Answer 58

massive bleeding that may result in death

Question 59

How does pulse repetition frequency (PRF) affect Doppler?

Answer 59

PRF allows one to record lower velocities as the PRF is lowered. as PRF is increased, the lower velocities are filtered out to record only the higher velocity signal

Question 60

How is PRF changed on the US machine?

Answer 60

with the scale control on the doppler panel (look at the color bar on the lt side of the monitor, the PRF will change as the "scale" on the doppler control is changed)

Question 61

What kind of PRF is needed in order to doppler flow in the hepatic venous system?

Answer 61

a lower PRF is necessary to record the flow pattern because flow in the hepatic venous system is low. As the flow increases beyond 40cm/sec the PRF should be increased to prevent aliasing

Question 62

If PRF increases what happens to imaging depth?

Answer 62

it also increases if imaging depth decreases, PRF also decreases

Question 63

What helps eliminate "noise" or low level Doppler shifts seen within the vessel?

Answer 63

Wall filters

Question 64

Doppler angle correction should be less than _______ to display the peak spectral velocity.

Answer 64

60 degrees

Question 65

What is the doppler flow in the splenic vein?

Answer 65

flow is reversed in the splenic vein...away from the liver

Question 66

What are the sonographic indications that cavernous transformation of the portal vein has occured?

Answer 66

extrahepatic portal vein is not visualized high level echoes producedd by fibrosis are present in the porta hepatis multiple tubular structures are present in the porta hepatis, representing periportal collaterals

Question 67

When there is portal venous hypertension what does Doppler determine?

Answer 67

whether portal flow is hepatopetal or hepatofugal

Question 68

What causes portal venous hypertension?

Answer 68

caused by the obstruction of the portal vein, hepatic vein, IVC prolonged congestive heart failure

Question 69

How is portal blood diverted when there is portal venous hypertension?

Answer 69

in a hepatofugal direction through collateral venous pathways with the formation of multiple portosystemic anastomoses

Question 70

When portal venous hypertension is present what happens to the velocity of blood flow?

Answer 70

Portal vein shows low velocity

Question 71

What vein gives the definitive diagnosis of Portal venous hypertension?

Answer 71

Patent paraumbilical vein

Question 72

Typical portal hypertensive venous flow varies... true or false?

Answer 72

True

Question 73

What two pathologies most frequently cause portal venous hypertension?

Answer 73

cirrhosis obstruction of portal venous radicles by fibrosis and regenerating nodules

Question 74

What do we see happen on US to the portal, splenic and superior mesenteric vein when there is portal venous hypertension?

Answer 74

These vessels are dilated

Question 75

When there is portal venous hypertension what happens to the spleen?

Answer 75

splenomegaly with dilated splenic radicles

Question 76

What does the liver look like when there is portal venous hypertension?

Answer 76

small liver with irregular surface or larger liver with abnormal texture

Question 77

What does TIPS stand for?

Answer 77

Transjugular Intrahepatic Portosystemic Shunt

Question 78

What are spontaneous intrahepatic portosystemic venous shunts?

Answer 78

rare disorders that describe abnormal connections between branches of the portal vein and systemic veins