Bma Illustrated Medical Dictionary

There are 2 different procedures: extra-
corporeal shock-wave lithotripsy (ESWL),
performed to break up small stones, and
percutaneous lithotripsy, performed on
larger stones. ESWL uses a machine
called a lithotripter, which produces
external shock waves. In percutaneous
lithotripsy, a nephroscope (an instru-
ment for viewing the kidney) is inserted
into the kidney and an ultrasonic probe
is directed through the nephroscope to
destroy the stone. Ureteric colic(severe
spasmodic pain in the side, occurring if
the ureter is obstructed by small frag-
ments of stone) may occur after ESWL.
People treated for gallstonesmay need
drug treatment to aid the final elimina-
tion of stone residues.
lithotripterThe machine used in extra-
corporeal shock-wave lithotripsy(ESWL)
to disintegrate small calculi(stones).
livedo reticularisA net-like, purple or
blue mottling of the skin, usually on the
lower legs, caused by the enlargement of
blood vessels beneath the skin. It is more
common in people with vasculitisand
those who suffer from excessive sensi-
tivity to cold. The condition is harmless,
and tends to be worse in cold weather.
liverThe largest organ of the body, this
roughly wedge-shaped, red-brown struc-
ture lies in the upper right abdominal
cavity, directly below the diaphragm. The
liver is divided into 2 main lobes, each
consisting of many lobules. These lob-
ules are surrounded by branches of the
hepatic artery, which supplies the liver
with oxygenated blood, and the portal
vein, which supplies nutrient-rich blood.
Deoxygenated blood from the liver drains
into the hepatic veins. A network of
ducts carries bilefrom the liver to the
gallbladderand the small intestine.
The liver plays a vital role in the body
because it produces and processes a
wide range of chemical substances. The
substances produced include important
proteins for blood plasma, such as albu-
min. The liver also produces cholesterol
and special proteins that help the blood
to carry fats around the body. In addition,
liver cells secrete bile, which removes
waste products from the liver and aids
the breakdown and absorption of fats in
the smallintestine (see biliary system).

Another major function is the processing

of nutrients for use by cells. The liver

also stores excess glucoseas glycogen.

In addition, it controls the blood levelof

amino acids(the building blocks of pro-

teins). If the level of amino acids is too

high, the liver converts the excess into

glucose, proteins, other amino acids, or

urea(for excretion).

Finally, the liver helps to clear the blood

of drugs and poisons. These substances

are broken down and excreted in the bile.

liver abscessA localized collection of

pusin the liver. The most common cause

is an intestinal infection. Bacteria may

spread from areas inflamed by divertic-

ulitisor appendicitis, and amoebaemay

invade the liver as a result of amoebiasis.

The symptoms are high fever, pain in the

upper right abdomen, and (especially in

elderly people) mental confusion. Ultra-

sound scanning usually reveals the

abscess. It can sometimes be treated by

aspiration, but often surgery is needed.

liver biopsyA diagnostic test in which

a small sample of tissue is removed from

the liver, usually under local anaesthesia.

The main function of this test is to diag-

nose liver diseases. (See also biopsy.)

liver cancerA cancerous tumour in the

liver. The tumour may be primary (origi-

nating within the liver) or secondary

(having spread from elsewhere, often the

LITHOTRIPTER LIVER CANCER

L

Stomach

Portal vein

Left lobe

of liver

Falciform

ligament

Hepatic

vein

Gallbladder Common bile duct

Pancreas

Hepatic artery

LIVER

Duodenum

Diaphragm

Right lobe

of liver