Sanders Exam Prep (Liver)

The correct answer is "Bare area". The liver is an intraperitoneal organ, meaning it is surrounded by peritoneum. However, the bare area of the liver is not covered by peritoneum. The bare area is a small portion on the posterior surface of the liver where it is in direct contact with the diaphragm, without any peritoneal covering.

Prothrombin time is a measurement of
one of the factors involved in blood clotting; it is affected
by the amount of vitamin K. A prolonged
prothrombin time is often an indicator of poor liver
function

Blood in the normal portal vein and the
hepatic artery is detectable with Doppler. In both
vessels, the blood flows hi the same direction—hepatopetal
flow (i.e., toward the liver). Turbulence is
not a characteristic of the flow in either vessel.

The hepatic artery normally runs between
the common bile duct and the portal vein.
It may have a tortuous course and usually bifurcates
proximal to the bifurcation of the common
hepatic duct.

In the fetus, the right branch of the umbilical
vein becomes the ductus venosus, which goes
into the inferior vena cava. After birth, the ductus
venosus becomes a fibrous cord called the ligamentum
venosum.

Hepatic veins do not have echogenic walls.

Hepatoblastoma causes liver enlargement
and occurs in small children. Rhabdomyosarcoma
affects the same age-group, but most often
develops around the bladder. Hepatocellular carcinoma
is typically seen in an older population. Focal
nodular hyperplasia is a benign mass. A hematoma
is a benign, blood-filled mass secondary to trauma.

The main portal vein and the hepatic artery
are responsible for supplying the liver with oxygen
and nutrients; however, the main portal vein is the
larger contributor.

Because of their close proximity to the
right atrium, hepatic veins exhibit a pulsatile,
choppy flow. Normal portal veins have a nonpulsatile,
even flow. The hepatic arteries have a low-resistance
arterial pattern. In normal patients, the superior
mesenteric artery Doppler signal changes
from a high- to low-resistance arterial pattern when
the patient goes from a fasting to postprandial
state. The iliac veins do not normally pulsate, although
the veins vary with respiration.

Hemangiomas are benign, vascular tumors

A Riedel's lobe is a long, thin extension of
the right lobe of the liver that can put the liver edge
well below the lower pole of the right kidney. Sonologists
using this criterion to make a diagnosis of hepatomegaly
will be guilty of not seeing the forest for
the trees—the entire liver must be taken into account.
The left lobe is often small in patients with a
Riedel's lobe, and patients with a small anteroposterior
diameter have livers that extend more inferiorly
to compensate. A Reidels lobe is unlikely to be
mistaken for any of the other options.

Jaundice brings to mind obstruction from
choledocholithiasis, but with an absence of gallstones
or shadowing throughout the liver a nonobstructive
cause should be considered. A subtle increase
in echogenicity of the portal triads is one of
the few sonographic indications of hepatitis; however,
this finding is not always present. It is possible
that the increase in periportal echogenicity is
caused by the decreased parenchymal echogenicity
sometimes seen in hepatitis. Pneumobilia would
cause linear echogenicity with dirty shadowing.
Choledocholithiasis would be seen as one or more
echogenic densities with acoustic shadowing.

Alanine aminotransferase (ALT) is also
known as serum glutamic pyruvic transaminase
(SGPT). It is the most specific laboratory test for
liver function. ALT is an enzyme produced in the
hepatocytes, and there are high concentrations of
ALT in the liver.

Shepherds are at risk for hydatid disease.
The eggs of this parasite are excreted in the feces
of infected animals, predominantly sheep, resulting
in humans becoming hosts. The liver is the
most common site for cyst development.

Presbyductia is a term used to describe
the normal enlargement of the common bile duct
with age. Although hyperbilirubinemia is usually
associated with liver disease or biliary obstruction,
it can occur in the presence of destruction of red
blood cells, as in hemolytic anemia.

Of the choices listed, only intravenous
antibiotics are not a cause of fatty infiltration of the
liver. Isolated fatty infiltration of the liver is a benign,
reversible disorder that affects the hepatocytes
and may interfere with liver function.

VitaminKlevels decrease inhepatocellular
disease, resulting in a prolonged prothrombin time
(PT). Prolonged PT carries a poor prognosis, but can
revert to normal if the liver damage is reversed.

The hepatic veins define the separation
between the lobes and segments of the liver. The
umbilical vein is no longer patent after birth. There
is no portal artery. The portal vein and hepatic arteries
supply the liver with oxygen and nutrients but
do not separate the lobes. The inferior vena cava
does not separate the lobes of the liver.

The sphincter of Oddi is at the entrance
of the common bile duct and pancreatic duct into
the duodenum; it does not lie in the porta hepatis.
Glisson's capsule refers to the fibrous tissue surrounding
the portal veins, bile ducts, and hepatic
arteries as they travel together in the liver. Glisson's
capsule also surrounds the liver. The common
hepatic duct becomes the common bile duct
at the point where it is joined by the cystic duct,
which is in the porta hepatis.

Acetylcholinesterase is not a laboratory value that can help distinguish between cirrhosis and a normal liver. Acetylcholinesterase is an enzyme that breaks down acetylcholine, a neurotransmitter. It is not specific to liver function and therefore would not be useful in differentiating between cirrhosis and a normal liver.

Hepatocellular disease refers to liver cell damage or dysfunction. Bilirubin, prothrombin time (PT), and aspartate aminotransferase (AST) are all markers of liver function and can increase in hepatocellular disease. However, acid phosphatase is not specific to liver function and is not typically elevated in hepatocellular disease. Therefore, acid phosphatase is the exception among the given options.

Cirrhosis of the liver is a chronic, progressive
disease caused by multiple factors that destroy the liver. Diabetes mellitus is caused by faulty insulin
production in the pancreas. If uncomplicated,
diabetes mellitus does not affect the liver.

Cirrhosis is a fibrotic process that causes
the liver to shrink. An enlarged liver occurs in the
early stages of alcohol-related liver disease when
there is fatty infiltration or hepatitis. A nodular outline,
increased echogenicity, and hepatofugalflow of
the portal veins are all features of severe cirrhosis.

Portal hypertension refers to an increase
in pressure in the portal venous system, usually
caused by liver disease or possibly portal vein
thrombosis. Hepatic artery thrombosis is not a
typical result of portal hypertension; however, the
portal vein often becomes thrombosed in portal
hypertension. Collaterals and splenomegaly result
from the pressure being reversed or forced to create
new paths.

Hepatofugal portal flow occurs in advanced
portal hypertension, a common sequel to
chronic cirrhosis. When sinusoidal resistance to
flow is so great that the direction of flow reverses,
portosystemic collaterals open up; the easiest to
detect is the recanalized paraumbilical vein that
travels in the ligamentum teres. To locate the paraumbilical
vein, find the ascending portion of the
left portal vein and follow the umbilical portion of
it inferiorly between the medial and lateral segments
of the left lobe of the liver. Color flow
Doppler will demonstrate flow and that the vein is
indeed recanalized.

Common bile duct obstruction is not associated
with hepatofugal flow. Hepatofugal flow
occurs when the pressure in the portal system of
the liver is increased and blood cannot flow
through the portal vein. A reversal of the normal
direction of flow is detected with Doppler imaging;
however, a poor Doppler angle may create
false direction of flow.

If a mass and ascites are discovered, it is
necessary to search carefully for metastases and
enlarged lymph nodes, treating the lesion as a
possible malignancy. However, in their absence,
this woman's history—especially the oral contraceptive
use—is appropriate for hepatic adenoma.
Hepatic adenomas are benign, so metastatic lesions
("bull's eye" or otherwise) would not be
present. The free fluid in her abdomen is from the
bleeding going on in her mass, which has ruptured
through the capsule into the peritoneum, irritating
it and causing her diffuse pain.

The middle and left hepatic veins border
the medial segment of the left lobe of the liver. The
ligamentum teres separates the lateral and medial
segments of the left lobe at a more inferior level. A
mass that touches the gallbladder would have to
be in the right anterior lobe. The main portal vein
and hepatic duct are down by the porta hepatis.The left portal vein lies exclusively in the lateral segment of the left lobe, not the medial segment.

This one is tricky I added it, but you will not be graded on this question. :)

A lobular outline to the liver is a feature
of cirrhosis, not hepatitis. Prominent portal vessels,
a thickened gallbladder wall, splenomegaly, and a
hypoechoic liver are all seen in hepatitis. Prominent
portal vessels, giving rise to the "starry night" appearance,are caused by edema of the liver.

The normal portal vein flows continuously
into the liver, which makes it a monophasic
waveform. Triphasic describes a waveform seen
particularly in the leg arteries and hepatic veins.

A high transverse view close to the diaphragm
best shows the three hepatic veins. The
veins join the inferior vena cava just below the diaphragm.
Longtudinal views only show a single
vein.

Isolated fatty infiltration of the liver is not
associated with gallbladder wall thickening. Acute
cholecystitis, AIDS, ascites, and hypoalbuminemia
all cause gallbladder wall thickening.

The waveforms of the hepatic vein, jugular
vein, femoral vein, and inferior vena cava all vary
with respiration. Only the portal vein waveform
does not vary with respiration.

The first four answers are absolute statements:
melanomas frequently metastasize to the
gallbladder; colon metastases are sometimes "bull's
eye" lesions; color flow Dopplermay show vascular
flow; and lymphomatous lesions in the liver are
usually hypoechoic, but not always. Actually, this
was a trick question to ask after the cautionary tip
about "never" being in the answer. However, in
this case "never" means "not always," so it is stopping
you from making an absolute statement.