Chapter 16- Abdominal Vasculature

Question 1

Explain an anomalous origin of the right hepatic artery

Answer 1

It originates as a branch of the SMA and has low resistance doppler waveforms

Question 2

Explain a duplicated or accessory renal artery

Answer 2

It originates from the aortic wall in about 20% of the population. It usually enters the upper or lower kidney instead of through the hilum. This typically occurs on the left side of the body

Question 3

What is a hilus or hilum?

Answer 3

An indentation in an organ (kidney, spleen etc) where vessels, ducts, and nerve fibers enter or leave.

Question 4

What is the diameter of the aorta?

Answer 4

2-2.5 cm

Question 5

What do normal abdominal ateries look like sonographically?

Answer 5

anechoic structures with bright, echogenic walls. The aorta displays pulsatility.

Question 6

What is shown with color doppler?

Answer 6

The passage of fluid through the circulatory system, the direction of flow, and the average velocity of the flow.

Question 7

What is Power Doppler?

Answer 7

A form of color doppler more sensitive to low flow states. It does not show the direction of flow.

Question 8

What is spectral doppler?

Answer 8

It shows blood movement over time using a pulsed wave to measure velocity in specific areas. It depicts velocity, direction of flow, and acceleration.

Question 9

What structures are high resistance and why?

Answer 9

Peripheral artieries and low-use organs. They don’t need as much blood supply.

Question 10

Do organs remain in one state of resistance or can they change?

Answer 10

They can change resistance. The femoral artery might be low resistance until you are running and needing bloody supply to the leg.

Question 11

What structures are low resistance and why?

Answer 11

Critical organs. Organs that are actively being used need more blood.

Question 12

Explain Pulsatile Flow

Answer 12

Arterial Flow where blood moves with a variable velocity and accelerates/deceerates with the contraction of the heart

Question 13

Is the SMA high or low resistance? How does this change with ingestion?

Answer 13

The SMA is high-resistance with low diastolic blood flow when fasting. After ingestion, the resistance is lower and there is an increase in blood flowing forward during diastole.

Question 14

Are the Renal Arteries high or low resistance? Why?

Answer 14

They have low-resistance waveforms because of the constant forward blood flow during the caridac cycle.

Question 15

Is the IMA high or low resistance?

Answer 15

The IMA is high resistance with low diastolic blood flow. It mimics the SMA during fasting.

Question 16

What systems are the abdominal venous structures divided into.

Answer 16

The Systematic System and the Portal System

Question 17

What structures are part of the Systematic System?

Answer 17

The IVC and its tributaries

Question 18

What does the Portal System do?

Answer 18

It carries blood from the spleen and bowel to the liver.

Question 19

Describe Duplication of the IVC

Answer 19

Duplication of the entire length OR short segmetns of the IVC

Question 20

Describe Partial Absence of the IVC

Answer 20

Segments absence of portions of the vessel

Question 21

Describe Transposition of the IVC

Answer 21

Relocation to the left of the aorta of the supra/infrarenal segment or the entire length of the IVC.

Question 22

Describe Phasic Flow

Answer 22

Venous flow that moves with variable velocity. The blood accelerates/decelerates with respiration.

Question 23

Do the Proximal and Distal IVC have the same or different waveforms?

Answer 23

Different. The proximal IVC has phasic flow whereas the distal IVC has pulsatile flow.

Question 24

Which portion of the IVC is closer to the heart, proximal or distal? Why?

Answer 24

Distal. The IVC runs inferior to superior.

Question 25

Hepatic veins are pulsatile in three phases. What do these phases do?

Answer 25

Two phases of flow toward the heart are followed by one phase away from the heart.
Looks like: –w^–w^–w^–

Question 26

What is Hepatopetal flow?

Answer 26

Blood flowing toward the liver.

Question 27

What is Hepatofugal flow?

Answer 27

Blood flowing away from the liver