Chapter 10 - Abdominal Venous System

What blood does the IVC work with?

Oxygen poor blood

Where does the IVC take blood to?

Back to the heart

Veins carry …

The same volume of blood as arteries, but at a lower pressure

Veins have a…

Diminished tunica media which allows for expansion

What do veins DO, that arteries DO NOT?

Compress with pressure

What DO veins contain, that arteries DO NOT?

Valves to prevent backflow

Where is the Inferior Vena Cava located?

Anterior to spine, to the right of the Aorta

Where does the IVC start and end?

Start - junction of Common Iliac Veins : Ends - in the Right Atrium of the heart (proximal toward feet, distal toward head)

What is the function of the IVC?

Bringing deoxygenated blood from lower extremities, abdominal & pelvic organs

What is the normal diameter of the Common iliac veins?

1.6-1.8cm

What is the normal length of the Right iliac vein?

5.5cm

What is the normal length of the Left iliac vein?

7.5cm

What is the normal diameter of the Inferior vena cava?

2.5cm

Where does the IVC course?

Straighter, and more horizontal : curves anteriorly at superior end as it enters the heart

Why is the Superior IVC easily visualized on US?

We use the liver as a window

Why is the Inferior IVC difficulty visualized on US?

Bowel, and it becomes smaller in diameter

Transposition - on the wrong side

Duplication - Two IVCs

What is interruption of an IVC?

Absence of IVC, EXTREMLY rare

What are IVC filters?

Small metal device placed by vascular surgeons into the IVC to catch blood clots before they move into lungs

Where are IVC filters placed?

Infrarenal IVC

What are largest tributaries of the IVC?

Hepatic Veins

What is the Hepatic Veins course?

Empty toward the diaphragm into IVC from origin in liver

Where does the liver receive blood from?

Hepatic Artery and Portal Vein

What is the function of the liver?

Processes blood and then returns it to IVC

What enlarges as they approach the diaphragm?

Hepatic Veins

What is important to do with the Portal Veins?

Make sure portal vein is flowing into the liver

What are the 3 Primary Hepatic Veins?

Right, Middle, and Left HV

Where does the Right HV drain into?

Right hepatic lobe

Where does the Middle HV lie?

Caudate lobe

Where does the Left HV course?

Left lobe of liver

The HVs are what kind of stucture?

Sonolucent structures embedded within the liver parenchyma

Sonolucent is another word for…?

Anechoic (black)

What plane is the HVs best imaged in?

Transverse plane, subcostally

How are the renal veins formed?

From tributaries the join in the renal hilum

Renal veins are seen ______ to Renal Arteries

Anterior

What is the best scanning plan to view the Renal Veins?

Transversely as they flow from renal sinus into posterior lateral aspect of IVC

Does the IVC appear (fuller or less full) above the entry of the RVs? And why?

Fuller: due to increase blood volume from the kidneys

Why does it seem fuller “above” the entry?

Because the blood is flowing superiorly

The Right Renal Vein is ______ than the Left.

Shorter

Where does the Right Renal Vein extend to?

Directly into the right side of the IVC

The Left Renal Vein is ______ than the Right. Why?

Longer; has to cross over the aorta to reach the left kidney

What veins come off the Left Renal Vein? And from what direction?

Superiorly - left adrenal vein & Inferiorly - left gonadal vein

What is the course of the Left Renal Vein?

Passes anterior to Aorta, posterior to SMA to enter the left side of IVC

Where does the Right Gonadal Vein drain?

Directly into the IVC

Where does the Left Gonadal Vein join?

Into the Left Renal Vein from the inferior position

What is the function of the Internal Iliac Veins?

Drain pelvic organs

What is the function of the External Iliac Veins?

Drain lower extremities

What does the Internal and External Iliac Veins become?

Common Iliac Veins

Right & Left Common Iliac Veins join together (Confluence) at level of umbilicus to form

Inferior Vena Cava