Damage to nerve tracts in the spinal
cord, which carry information from pos-
ition sensors in the joints and muscles,
can also impair balance. This damage
may result from spinal tumours, circula-
tory disorders, nerve degeneration due
to deficiency of vitamin B 12 , or, rarely,
tabes dorsalis (a complication of syph-
ilis). A tumour or stroke that affects the
cerebellum may cause clumsiness of
the arms and legs and other features
of impaired muscular coordination.
balanitisInflammation of the foreskin
and glans (head) of the penis. Balanitis
causes pain and/or itchiness, and the
entirearea may be red and moist. Causes
include infection or chemical irritation
by contraceptive creams or laundry prod-
ucts. Treatment is usually with antibiotic
or antifungal drugs(as creams or taken
orally) and careful washing of the penis
and foreskin. Phimosis, in which the
foreskin is overly tight, makes balanitis
more likely to recur. In such cases, cir-
cumcisionmay be recommended.
baldnessSee alopecia.
balloon catheterA flexible tube with a
balloon at its tip, which, when inflated,
keeps the tube in place or applies pres-
sure to an organ or vessel. One type is
used to drain urine from the bladder
(see catheterization,urinary). Balloon
catheters are sometimes used to expand
narrowed arteries (balloon angioplasty).
They may also be used to control bleed-
ing oesophageal varicesbefore surgery.
balmA soothing or healing medicine
applied to the skin.
bambuterolA bronchodilator drugthat
is converted to terbutalinein the liver.
Bambuterol can only be taken orally.
bandageA strip or tube of fabric used
to keep dressingsin position, to apply
pressure, to control bleeding, or to sup-
port a sprain or strain. Roller bandages
are the most widely used. Tubular gauze
bandages require a special applicator
and are used mainly for areas that are
awkward to bandage, such as a finger.
Triangular bandages are used to make
slings. (See also wounds.)
barber’s itchSee sycosis barbae.
barbiturate drugsA group of sedative
drugsthat work by depressing activity
within the brain. They include thiopental
and phenobarbital. In the past, barbitu-
rates were widely used as antianxiety
drugsand sleeping drugsbut have been
largely replaced by benzodiazepine drugs
and other nonbarbiturates. Barbiturates
are now strictly controlled because they
are habit-forming and widely abused.
An overdose can be fatal, particularly in
combination with alcohol, which danger-
ously increases the depressant effect
on the brain (including suppression of
the respiratory centre). However, pheno-
barbital is still commonly used as an
anticonvulsant drugin the treatment of
epilepsy. Thiopental is very short acting
and is used to induce anaesthesia (see
anaesthesia,general).
barium X-ray examinationsProce-
dures used to detect and follow the
progress of some gastrointestinal tract
disorders. Because X-raysdo not pass
through it, barium is used to outline
organs, such as the stomach, which are
not normally visible on an X-ray. In
some cases, barium X-rays are an alt-
ernative to endoscopy.Barium sulphate
mixed with water is passed into the part
of the tract requiring examination, and
X-rays are taken. X-rays may be single-
or double-contrast. Single-contrast bar-
ium X-rays use barium sulphate alone.
The barium fills the section of the tract
and provides an outline image that
shows up prominent abnormalities. In
double-contrast barium X-rays, the bar-
ium forms a thin film over the inner
surface of the tract, and the tract is
filled with air so that small surface
abnormalities can be seen.
Different types of barium X-ray exam-
ination are used to investigate different
parts of the gastrointestinal tract. Bar-
ium swallow involves drinking a barium
solution and is used to investigate the
oesophagus. A barium meal is carried
out to look at the lower oesophagus,
stomach, and duodenum. Barium follow-
through is used to investigate disorders
of the small intestine; X-rays are taken
at intervals as the barium reaches the
intestine. A barium enema is used to
investigate disorders of the large intes-
tine and rectum; barium is introduced
though a tube inserted in the rectum.
Barium remaining in the intestine mayBALANITIS BARIUM X-RAY EXAMINATIONS
B