Unit 1 Liver Study Guide

Which organ is the largest in the body?

Liver

What is the normal echo texture of the liver?

Homogenous and fine low level echoes

Describe the liver in comparison to the kidney.

The liver is Isoechoic to slightly hyperechoic

What regions does the liver occupy?

Lies in the right hypochondrium, epigastrium, and left hypochondium

Where does the liver lie in respect to the diaphragm?

Directly below

The stomach is ___________ and _________ to the left lobe of the liver.

Posterior, lateral

Which border of the liver comes in contact with the right kidney?

The posterior border and the inferior border

The IVC and aorta lie ___________,___________ to the liver.

Posterior, medial

The pancreas is ________________ to the left liver.

Just inferior

Is the liver contained within the peritoneum?

Yes, all but the bare area?

What is the bare area?

Portion that touches the diaphragm

Where is the subphrenic space located?

Between the liver (or spleen) and the diaphragm

Which lobe of the liver is the largest?

The right lobe

Which lobe of the liver is the smallest lobe?

The caudate lobe

The caudate lobe is located where?

Posterior and inferior to the left lobe

Describe the quadrate lobe.

“Forth” lobe of the liver, which is actually the medial portion of the left lobe

The anterior border of the caudate lobe is bordered by…

The left portal vein and the ligamentum venosum

The posterior border of the caudate lobe is bordered by…

The IVC

What is special about the caudate lobe in terms of vasculature?

It is supplied with blood via branches of both the right and left portal veins and the hepatic arteries and is drained by small veins known as emissary veins which enter the IVC directly

What veins drain the caudate lobe?

Emissary veins

Why do we use Couinaud’s Liver Anatomy?

It is the basis for surgical resection, and uses venous anatomy of liver to divide into segments (PV & HV)

Ligaments and fissures will appear how on ultrasound?

Hyperechoic

What is the connective tissue layer called that surround the liver?

Glisson’s capsule

What is the porta hepatis?

Opening of the liver through which the portal veins ash hepatic arteries enter and the bile ducts exit.

Where is the main lobar fissure located?

Extends from gallbladder fossa to IVC

What does the main lobar fissure look like on ultrasound?

A thin, bright (echogenic) line connecting the gallbladder neck to the portal vein

What lies in each fissure? Right Intersegmental & left Intersegmental

Right: Right HV

Left: Ligamentum teres, falciform ligament, left HV and left PV

The right Intersegmental fissure divides the liver into…

Divides the right lobe into anterior and posterior segments

The left Intersegmental fissure divides the liver into…

Divides the left liver into medial and lateral segments

The main lobar fissure divides the liver how?

Divides right and left lobes obliquely

What is another name fore the main lobar fissure?

Rex-Cantlie line

The tip or terminal end of the falciform ligament is called…

Ligamentum teres

Which of the veins in the liver is hepatopedal? What does this mean?

Portal vein and flow towards the liver

Which of the veins in the liver is hepatofugal? What does this mean?

Hepatic veins, takes blood away from the liver

The hepatic veins divide the liver into…

Right: separates and drains the anterior and posterior portions of the R lobe

Left: separates and drains the medial and lateral portions of the L lobe

Middle: separates the right liver from the medial left liver and drains the right liver and the medial lobe of the L liver

Are the portal veins intralobar or Intersegmental? Why is this important to know?

Intralobar (Intersegmental). This is important to know because intralobar means that the veins that the veins are within the lobes (segments) of the liver.

What makes up the portal triad? What is this “sign” called?

Portal vein, hepatic artery, Common bile duct; The “Mickey Mouse” sign

Are the hepatic veins Intersegmental, interlobar, or intrasegmental?

Interlobar / Intersegmental

Describe the differences in the portal veins and hepatic veins appearances by ultrasound.

The portal veins have walls that appear very bright in contrast to their anechoic lumens, whereas the hepatic veins tend to not have very bright walls.

The common hepatic artery is a branch of the what?

Celiac axis

The proper hepatic artery is located __________ to the MPV.

Parallel

What does the CHA become?

Proper hepatic artery

What does the PHA divide into?

Right and left hepatic arteries

What type of resistance is the hepatic artery? Define?

How-resistance; constant/steady flow

What are the functions of the liver? Be able to describe each one very simply.

Metabolism: the physical and chemical process of food being synthesized into complex elements and then tranformed to simple ones to create energy for the organism.

Digestion: The liver creates bile which plays an important role in fat absorption. Bile is the waste that has been produced during metabolism . Bilirubin is also released when red blood cells are broken down and is excreted in the bile.

Storage: the liver is a storage site for several compounds used in a variety of physiologic activities throughout the body (E.X: vitamins / iron)

Detoxification: the lover detox’s waste products of metabolism accumulated from other sources in the body and foreign chemicals that enter the body.

What is glycogenesis?

The formation and storage of glycogen

What is one of the main proteins discussed that is produced from metabolism?

Albumin

What is ammonium detoxification?

The liver converts ammonia (harmful), a product of protein metabolism, into Arginine (a useful amino acid) and urea (a waste product)

What is bilirubin detoxification?

Bilirubin is create when hemoglobin is broken down. The liver also detoxes it and excretes it in the bile to the gut via the biliary tree.

What is bile? What is its function?

The excretory product of the liver. It is composed of water, bile salts, and bile pigments.

To emulsify intestinal fat and remove waste products excreted by the liver

What are bile pigments?

Seen on ultrasound as echogenic. Can be due to cholesterol crystals or stasis.

What is the liver ultrasound prep?

NPO prior to exam (we say about 8 hours)

What type of transducers may be used (MHz)?

Average adult abdomen: 2.5-5 MHz

Obese adults: 2.25 MHz

Slender adults and children: 5-7 MHz

Neonate: 7.5-12 MHz

What is the normal liver size?

Approx. 1500 grams in adults, up to 15.5 cm

What vessels meet at the portosplenic confluence?

Splenic vein, superior mesenteric vein, inferior mesenteric vein

Morrison’s pouch is where?

Between the right lobe of the liver and right kidney

The falciform ligament was the passageway of what embryonic vessel?

Embryonic umbilical vein

Ligamentum venosum is a remnant of…

The fetal ductus venous

The right and left triangular ligaments are extensions of?

Right: coronary artery

Left: the falciform ligament