Liver Ultrasound Anatomy and Protocols

What is the recommended NPO fasting time for a patient before a liver ultrasound exam?

8 to 12 hours.

What transducer frequency is typically used for a liver ultrasound exam?

3.0 or 3.5 MHz.

What breathing technique is recommended for imaging the liver?

Deep, held inspiration.

What alternative breathing technique can be used if deep inspiration does not work?

Quiet respiration and holding breath out.

What pushing technique may be needed during a liver scan to maintain contact?

Moderate pressure.

What is the standard initial patient position for a liver ultrasound?

Supine.

What alternative patient positions can be used for a liver scan?

Left lateral decubitus, oblique, and upright.

In which abdominal quadrant is the liver primarily located?

Right Upper Quadrant.

Where does the left lobe of the liver extend towards?

Towards the midline, sometimes stretching into the Left Upper Quadrant.

Where is the caudate lobe located on the liver?

On the posterior surface, between the ligamentum venosum and the IVC.

Which part of the liver is intraperitoneal except for specific regions like the bare area?

Most of the liver's posterior surface and surrounding structures.

Which liver surfaces abut the diaphragm?

Superior, posterior, and anterior surfaces.

What is the largest internal organ in the human body?

The liver.

Which liver lobe is considerably larger than the other?

The right lobe.

What is the typical shape of the right lobe of the liver?

A wedge shape.

What is the upper limit of normal for liver length?

15 to 16 cm.

What structure encases the entire liver?

Glisson's capsule.

How is the normal echotexture of the liver described?

Homogeneous with midlevel echogenicity.

What disrupts the homogeneous echotexture of the liver?

Vessels and ducts.

What anatomical structures define the liver's anatomy?

Lobes (Left, Right, Caudate, and Quadrate).

What anatomical structures define the liver's function, blood supply, and biliary drainage?

Segments (Right, Left, and Caudate).

What ligament forms the superior surface border of the left lobe from the right lobe?

Falciform ligament.

What anatomical feature forms the caudate surface border of the left lobe?

Fissure for the Ligamentum Venosum.

What ligament forms the inferior surface border of the left lobe from the quadrate lobe?

Ligamentum Teres.

What ligament forms the superior surface border of the right lobe from the left lobe?

Falciform Ligament.

What anatomical structure forms the inferior surface border of the right lobe?

Left Intersegmental fissure.

What is Riedel's lobe?

A normal anatomic variant that is a tongue-like projection of the right lobe.

What is the quadrate lobe?

The medial portion of the left lobe of the liver.

What is the superior landmark of the quadrate lobe?

Fissure of the Ligamentum Venosum.

What is the right landmark of the quadrate lobe?

IVC.

What is the left landmark or edge of the quadrate lobe?

Its margin (edge).

What is the anterior landmark of the quadrate lobe?

Porta Hepatis.

What is the posterior landmark of the caudate lobe?

Porta Hepatis.

What is the anterior landmark of the caudate lobe?

Margin of the liver.

What is the right landmark of the caudate lobe?

Gallbladder fossa.

What is the left landmark of the caudate lobe?

Fissure of the Ligamentum Teres.

Which vessel is located in the main lobar fissure and separates the liver into right and left functional units?

Middle Hepatic Vein(s).

What does the right functional lobe encompass?

Everything to the right of the GB fossa and IVC.

Which vein divides the right functional lobe into anterior and posterior segments?

Right Hepatic Vein.

What does the left functional lobe encompass?

Everything to the left of the GB fossa and IVC.

Which structures subdivide the left functional lobe into medial and lateral segments?

Left Portal Vein, Left Hepatic Vein superiorly, and Ligamentum Teres inferiorly.

From which lobes does the caudate lobe receive blood?

From both the right and left lobes.

Does the caudate lobe have sub-divisions?

No, it has no sub-divisions.

Which three liver ligaments are commonly seen on ultrasound?

Falciform Ligament, Ligamentum Teres, and Ligamentum Venosum.

What are some of the less commonly seen liver ligaments?

Coronary Ligament, Right and Left Triangular Ligaments, Gastrohepatic Ligament, and Hepatoduodenal Ligament.

What is the function of the hepatic veins?

To drain blood from the liver to the IVC.

How do the hepatic arteries run relative to the portal veins?

Anterior to the Portal Veins.

What blood vessels form the portal venous system confluence?

Splenic vein, SMV, and IMV.

What components make up the Portal Triad?

Hepatic Artery, Bile Duct, and Portal Vein.

How do portal veins and hepatic veins differ in their branching appearance?

Hepatic veins branch like Christmas trees, while portal veins branch at 90-degree angles.