BASAL CELL CARCINOMA
SYMPTOMS
Minor pressure damage in the middle ear
may cause pain, hearing loss, and
tinni-
tus
(ringing in the ears) for a few days;
damage in the facial sinuses may also
cause pain, and possibly a discharge of
mucus or blood. Symptoms usually wear
off within hours or days, but treatment
may be needed if they worsen or persist.
Large changes in pressure can rupture
the eardrum (see
eardrum, perforated).
PREVENTION
Barotrauma can be avoided by vigorous
swallowing or by forcibly breathing out
with the mouth closed and the nose
pinched, which is known as the Valsalva
manoeuvre. This action serves to equal-
ize the internal and external pressures
in the middle ear and sinuses.
If the eustachian tubes are blocked, as
commonly occurs with a cold, use of a
nasal spray containing a
decongestant
drug
is recommended shortly before the
descent of the aircraft. Anyone with a
severe head cold should avoid air travel
if possible. Infants should be breast- or
bottle-fed during descent to encourage
swallowing. (See also
aviation medicine;
scuba-diving medicine.)
L
Mechanism of barotrauma
The diagram above shows the location of the
middle ear and the pressure changes that occur
when the eustachian tube is blocked and there
is an increase in surrounding air pressure.
barrel chest
A prominent, rounded chest that is
sometimes the result of lung distension
in people with longstanding
emphysema
(enlarged air sacs in the lungs). Lung
distention leads to an increase in dis-
tance between the front and back of the
chest, thereby resulting in a change in
the shape of the chest wall. (See also
pulmonary disease, chronic obstructive.)
Barrett’s oesophagus
A complication of long-term gastro-
oesophageal reflux (see
acid reflux),
in
which the cells that line the lower part
of the oesophagus are replaced by cells
that are normally found in the stomach.
People with Barrett’s oesophagus are at
increased risk of developing cancer of
the oesophagus (see
oesophagus, cancer
of
). The condition may be monitored
regularly by
endoscopy
(internal exam-
ination using a viewing instrument) of
the oesophagus.
barrier cream
A cream that is used to protect the skin
against the effects of irritant substances
and excessive exposure to water. (See
also
sunscreens
.)
barrier method
A method of preventing pregnancy by
blocking the passage of sperm to the
uterus (see
contraception, barrier methods
of
). An example of a barrier method is
the use of a condom or a diaphragm.
barrier nursing
The nursing technique by which a
patient with an infectious disease is pre-
vented from infecting other people (see
isolation).
In reverse barrier nursing, a
patient with reduced ability to fight
infections (for example, because of an
immunodeficiency disorder
or following
certain types of surgery) is protected
against outside infection. (See also
asep-
tic technique.)
bartholinitis
An infection of the
Bartholin’s glands
at
the entrance to the vagina.The disorder,
which may be due to a
sexually transmit-
ted infection
such as
gonorrhoea,
causes
an intensely painful red swelling at the
opening of the gland ducts. Treatment
is with
antibiotic drugs
,
analgesic drugs
,
and warm baths.
Bartholinitis sometimes leads to the
formation of an abscess (see
Bartholin’s
abscess
) or a painless cyst, known as a
Bartholin’s cyst, which may become
infected. Abscesses are drained under
general
anaesthesia
(see
anaesthesia,
general).
Recurrent abscesses or infected
cysts may require surgery to convert the
duct into an open pouch (see
marsupial-
ization)
or remove the gland completely.
Bartholin’s abscess
The formation of pus in one or both of
the
Bartholin’s glands,
which are located
on either side of the vulva (the folds of
flesh that surround the opening of the
vagina). Bartholin’s abscesses develop as
a result of bacterial infection of the
glands (see
bartholinitis).
Bartholin’s glands
A pair of oval, pea-sized glands whose
ducts open into the vulva (the folds of
flesh that surround the opening of the
vagina). During sexual arousal, the Bar-
tholin’s
glands
secrete
a
fluid that
lubricates the vulval region. Infection
of these glands causes
bartholinitis
or the
development of a
Bartholin’s abscess.
basal cell carcinoma
A type of skin cancer, also known as a
rodent ulcer or BCC, that occurs most
commonly on the face or neck, but can
affect any part of the body. The cells of
the tumour closely resemble, and are
possibly derived from, cells in the basal
(innermost) skin layer.
Basal cell carcinoma is caused by skin
damage from the ultraviolet radiation
in sunlight. Fair-skinned people over
the age of 5
0
are most commonly
affected by this form of cancer; dark-
skinned people are protected by the
larger amount of
melanin
(a pigment
that absorbs ultraviolet radiation)
in
their skin. The incidence of basal cell
carcinoma is much higher among peo-
ple living in sunny climates, especially
those who have outdoor occupations;
in parts of the US and Australia, over
half the white population has had a
basal cell carcinoma by the age of 75.
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