ERCP
order to facilitate the delivery of a baby.
After delivery, the severed tissues are
stitched back together.
WHY IT
IS DONE
An episiotomy is advisable if the peri-
neum fails to stretch over the baby’s
head and/or a large perineal tear is like-
ly The procedure prevents ragged tears
that would be more painful, more diffi-
cult to repair, and more likely to lead to
complications.
Episiotomy
is
usually
necessary in a
forceps delivery
,
because
the instruments occupy additional space
in the vagina, and in a
breech delivery
,
in
which there is little opportunity for
gradual stretching of the perineal tissues.
In most cases, however, the naturally
elastic vagina should not have to be cut
to allow a normal delivery.
epispadias
A rare congenital (present from birth)
abnormality in w hich the opening of
the
urethra
(the tube through w hich
urine is excreted from the bladder) is
not in the glans (head) of the
penis
but
is on its upper surface. In some cases,
the penis also curves upwards. Surgery
is carried out during infancy, using tis-
sue from the
foreskin
to reconstruct the
urethra. (See also
hypospadias
. )
epistaxis
A medical term for
nosebleed
.
epithelioma
A noncancerous tumour arising from
the
epithelium
,
the tissue that covers the
outer surface of the body and forms
the
membranous
lining
of internal
organs). In some cases, an epithelioma
may become cancerous, in w hich case
it becomes known as a
carcinoma
.
epithelium
The layer of
cells
that covers the entire
surface of the body and lines most of
the structures within it. Epithelial cells
vary in shape according to their func-
tion. There
are
three
basic
shapes:
squamous (thin and flat), cuboidal, and
columnar. These structures may vary
further. For example, in the respiratory
tract, epithelial cells bear brushlike fila-
ments called cilia that create a current in
the surrounding fluid. This current pro-
pels dust particles from inhaled air back
up the bronchi (the large air passages in
the lungs) and the trachea (windpipe).
Most
internal
organs
lined
with
epithelium are covered with only a sin-
gle layer of cells, but the skin, w hich is
subjected to more trauma, consists of
many layers including a dead outer layer
of cells that is constantly being shed.
Structures
that
are
not
lined
with
epithelium are the blood vessels, the
lymph vessels
(see
lymphatic system
) ,
and the inside of the heart, w hich are
lined with
endothelium
,
and the chest
and abdominal cavities, w hich are lined
with
mesothelium
.
S q u a m o u s c e l l s
Squamous
Types of epithelium
The cells ofthe epithelium varyin shape and size
according to function. The three basictypes are
squamous, cuboidal, and columnar.
epoetin
A genetically engineered preparation of
the
hormone
erythropoietin, w hich is
produced by specialized cells in the kid-
neys and stimulates the
bone marrow
to
produce
red blood cells
.
Epoetin may be used in the treatment
of
anaemia
(a reduced level of the oxy-
gen-carrying pigment haemoglobin in
the blood) due to the lack of erythropo-
etin that occurs in
kidney failure
.
It is also
used to boost the level of red blood cells
before surgery; the patient donates blood
to be used during or after the surgery
beforehand. Epoetin may also be used as
an alternative to blood transfusions in
major orthopaedic (bone) surgery
Epstein-Barr virus
A
virus
that belongs to the herpesvirus
family The Epstein-Barr virus (EBV) may
cause glandular fever (see
mononucleo-
sis, infectious
) ;
after the initial infection,
the virus remains dormant in the cells
of the immune system and may later be
reactivated. Epstein-Barr virus is one of
the few viruses with a proven role in
the development of cancerous tumours.
In Africa, it is associated w ith
Burkitt’s
lymphoma,
and in Southeast Asia it is
associated with cancer of the
naso-
pharynx
(see
nasopharynx, cancer of).
Epstein-Barr virus may also cause lym -
phomas to develop in patients who have
undergone transplant surgery.
Other disorders that are associated
w ith Epstein-Barr virus include some
cases of acute
hepatitis.
In people with
AIDS, the virus may lead to the develop-
ment of a condition called oral hairy
leukoplakia;
this condition is character-
ized by roughened, white patches on
the sides of the tongue.
Erb-Charcot disease
A rare condition resulting from spinal
cord damage due to
syphilis
(a sexually
transmitted
bacterial
infection).
The
symptoms include numbness, a sensa-
tion of pins and needles, and muscle
weakness in the legs.
Erb’s palsy
Weakness or paralysis of the muscles in
the upper arm and shoulder. Erb’s palsy
results from damage to the upper roots
of the
brachial plexus
(a collection of
nerve trunks formed from nerve roots
near the top of the spine). Such an
injury may occur during birth if excess
pressure is applied to the baby’s head
during a difficult delivery, causing the
fifth cervical root of the spinal cord to
be damaged. It may also result from a
road
traffic
accident,
particularly
in
motorcycle
riders,
when
an
impact
forces the head and neck to one side
and severely strains the nerves on the
opposite side. Erb’s palsy is character-
ized by an arm that is rotated inwards at
the shoulder and hangs limp down one
side of the body
ERCP
The abbreviation for endoscopic retro-
grade cholangiopancreatography, which
is an
X-ray
procedure used for examin-
ing the
biliary system
and the pancreatic
duct. ERCP is used mainly when other
imaging techniques, such as
ultrasound
scanning, CTscanning,
or
MRI,
fail to pro-
vide
sufficiently
detailed
images
of
these body structures.
HOW
IT IS DONE
An
endoscope
(a flexible viewing tube
w ith a lens and a light attached)
is
passed down the oesophagus, through
E
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