MENISCUS
Meningiomas can be detected by
X - r a y
or
C T s c a n n i n g ,
or by MR/.The tumours can
often be completely removed by surgery.
Otherwise, treatment is by
r a d i o t h e r a p y .
m e n in g itis
Inflammation of the
m e n i n g e s
(memb-
ranes
covering
the
b r a i n
and
s p i n a l
c o r d ) ,
usually due to infection.
CAUSES
Viral meningitis tends to occur in epi-
demics in winter; it is usually relatively
mild. Bacterial meningitis, however, is
life-threatening. It is mainly caused by
H
a e m o p h il u s
in f l u e n z a e
, S
t r e p t o c o c c u s
p n e u
-
m o n i a e
, or M
e n i n g o c o c c u s
types B and C.
The
infection
usually
reaches
the
meninges via the bloodstream from an
infection elsewhere in the body, often
in the nose or throat. Less commonly, it
passes through skull cavities from an
infected ear or
s i n u s ,
or from the air fol-
lowing a
s k u l l f r a c t u r e .
SYMPTOMS
The main symptoms are fever, severe
headache, nausea and vomiting, dislike
of light, and a stiff neck. In viral menin-
gitis, the symptoms are m ild and may
resemble influenza. In bacterial menin-
gitis, the main symptoms may develop
over only a few hours, followed by
drowsiness and,
occasionally,
loss of
consciousness. In about half the cases of
meningococcal meningitis, there is also
m e n i n g o c o c c a e m i a
(a
potentially
life-
threatening condition in w hich bacteria
multiply rapidly in the blood). This
condition causes a reddish-purple rash
under the skin, w hich does not fade
with pressure (see
g l a s s t e s t
). The rash
starts as pin-prick spots that can expand
to give a bruiselike appearance.
DIAGNOSIS AND TREATMENT
To make a diagnosis, a
l u m b a r p u n c t u r e
is
performed to remove a small sample of
cerebrospinal fluid.
Viral meningitis needs no treatment
and usually clears up in a week or two
with no after-effects. Bacterial meningitis
is a medical emergency. It is treated with
intravenous
a n t i b i o t i c d r u g s .
W ith prompt
treatment, a full recovery is usually made;
the earlier treatment is given, the better
the outlook. In some cases, however,
d e a f n e s s
or
b r a i n d a m a g e
may occur, or
the person may lose an area of skin, or
fingers or toes, as a result of the rash.
PREVENTION
Vaccines are now given to protect chil-
dren and teenagers against two of the
major types
of bacterial meningitis:
those caused by H
a e m o p h il u s in f l u e n z a e
and
by M
e n i n g o c o c c u s
type C (see
i m m u n i z a -
t i o n ) .
Antibiotic drugs may be given as a
protective measure to people who have
come into contact with these infections.
Immunization against some forms of
meningitis is recommended for Mus-
lims travelling to Saudi Arabia for the
Hajj and Umrah pilgrimages, and for
people travelling to Nepal and some
parts of sub-Saharan Africa.
m e n in g o c e le
A protrusion of the spinal cord’s
m e n -
i n g e s
(protective coverings) under the
skin. It is caused by a congenital defect
in the spine (see
s p i n a b i f i d a ) .
m e n in g o c o c c a e m ia
An acute, life-threatening infection of the
bloodstream
caused by M
e n i n g o c o c c u s
bacteria; also called meningococcal sep-
ticaemia. It may occur with uncontrolled
m e n i n g o c o c c a l m e n i n g i t i s
and produces
the characteristic, reddish-purple rash
often seen in this condition.
Meningococcaemia can cause
s h o c k
;
k i d n e y f a i l u r e ;
and the loss of areas of
skin, or fingers and toes, due to blood
vessel damage. It can be fatal. Affected
people need to be admitted to hospital
immediately. Treatment is with
a n t i b i o t i c
d r u g s
followed by
i n t e n s i v e c a r e .
m e n in g o c o c c a l m e n in g itis
One of the most common forms of bac-
terial
m e n i n g i t i s .
Most cases occur in
children or young adults. The disease is
transmitted by exhaled droplets; it can
spread rapidly through groups of peo-
ple who are in close contact with each
other, such as children in boarding
schools. If not treated promptly, it may
progress to the life-threatening disorder
m e n i n g o c o c c a e m i a
.
m e n in g o c o c c a l ra sh
A rash that occurs in about half of all cases
of
m e n i n g o c o c c a l m e n i n g i t i s
and meningo-
coccal
s e p t i c a e m i a .
The
rash
arises
as
pin-prick spots beneath the skin that join
together to give the appearance of a bruise
(see
p u r p u r a
). The rash associated with
meningococcal infection does not fade
when pressure is applied (see
g l a s s t e s t ) .
m e n in g o e n c e p h a litis
Inflammation of the
b r a i n
and the
m e n -
i n g e s
(the membranes surrounding the
brain), usually as a result of a viral
infection. See
e n c e p h a l i t i s
.
m e n in g o m y e lo c e le
Another name for
m y e l o m e n i n g o c e l e
.
m e n is c e c to m y
A surgical procedure in w hich all or
part of a damaged
m e n i s c u s
(cartilage
disc) is removed from a joint, almost
always from the knee.
WHY IT IS DONE
Meniscectomy may be performed when
damage to the meniscus causes the knee
to lock or to give way repeatedly. It cures
these symptoms and reduces the risk of
premature
o s t e o a r t h r i t i s
in the joint.
HOW IT IS DONE
A r t h r o s c o p y
(in w hich a viewing instru-
ment is inserted into the joint through a
small incision) may be carried out to
confirm and locate the damage. The
damaged area may then be removed by
instruments passed through the arthro-
scope. Alternatively, the meniscus may
be removed through an incision at the
side of the
p a t e l l a
(kneecap).
OUTLOOK
In either case, there may be an increased
risk of osteoarthritis in later life, but
this is less than if the damaged menis-
cus had been left in place.
m e n is c u s
A crescent-shaped disc of cartilaginous
tissue found in several joints. The
k n e e
joint has two menisci, and the
w r i s t
M
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