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
gallstones
may need
drug treatment to aid the final elimina-
tion of stone residues.
lithotripter
The machine used in extra-
corporeal shock-wave
lithotripsy
(ESWL)
to disintegrate small
calculi
(stones).
livedo reticularis
A 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
vasculitis
and
those who suffer from excessive sensi-
tivity to cold. The condition is harmless,
and tends to be worse in cold weather.
liver
The 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
bile
from the liver to the
gallbladder
and 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 small intestine (see
biliary system
).
LITHOTRIPTER
LIVER CANCER
LIVER
Another major function is the processing
of nutrients for use by cells. The liver
also stores excess
glucose
as glycogen.
In addition, it controls the
blood level
of
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 abscess
A localized collection of
pus
in the
liver
. The most common cause
is an intestinal infection. Bacteria may
spread from areas inflamed by
divertic-
ulitis
or
appendicitis
, and
amoebae
may
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 biopsy
A 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 cancer
A cancerous tumour in the
liver.
The tumour may be primary (origi-
nating within the liver) or secondary
(having spread from elsewhere, often the
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