MYECTOMY
MYOCARDIAL INFARCTION
myectomy
Surgical removal of part or
all of a muscle. Myectomy may be per-
formed to treat severely injured and
infected muscles or to remove a fibroid
in an operation called a
myomectomy.
myel
- A prefix that denotes a relation-
ship to bone marrow (as in
multiple
myeloma
) or to the spinal cord (as in
myelitis
). The prefix myelo- has the
same meaning.
myelin
The fatty material made of
lipid
(fat) and protein that forms a protective
sheath around some nerve fibres and
increases the efficiency of nerve impulse
transmission. (See also
demyelination.)
NERVE CELL
myelitis
Inflammation of the spinal cord,
often caused by a viral infection. In trans-
verse myelitis, the spinal cord becomes
inflamed around the middle of the back.
Common symptoms are back pain and
gradual
paralysis
of the legs, which, in
some cases, becomes permanent.
myelocele
Another name for
myelo-
meningocele
(see
neural tube defect
).
myelofibrosis
An alternative term for
myelosclerosis.
myelography
X-ray
examination of the
spinal cord, nerves, and other tissues
within the spinal canal after injection of
a contrast medium (a substance that is
opaque to X-rays).
The procedure has now been replaced
by
CT scanning
and
MRI.
myeloma, multiple
See
multiple myeloma.
myelomatosis
See
multiple myeloma
.
myelomeningocele
A protrusion of the
spinal cord
and its
meninges
(protective
membranes) under the skin due to a con-
genital defect (see
neural tube defect
).
myelopathy
Any disease or disorder of
the
spinal cord.
myelosclerosis
An increase of fibrous
tissue within the
bone marrow
(also
known as myelofibrosis), in which the
marrow's ability to produce blood cells
is impaired. Myelosclerosis may be pri-
mary (occurring with no obvious cause)
or secondary (resulting from another
bone marrow disease).
The main symptoms of myelosclerosis
are those of
anaemia
. Enlargement of the
spleen
, night sweats, loss of appetite,
and weight loss also commonly occur.
In secondary myelosclerosis, the under-
lying disease may cause other symptoms.
Treatment of primary myelosclerosis
includes
blood transfusions
to relieve
symptoms. A few patients may develop
acute
leukaemia
.
Treatment of second-
ary myelosclerosis depends on
the
underlying cause.
myiasis
An infestation by fly larvae,
which is primarily restricted to tropical
areas. In Africa, the tumbu fly lays eggs
on wet clothing left outside; the larvae
hatch and penetrate the skin to cause
boil-like swellings. Other flies may lay
eggs in open wounds, on the skin, or in
the ears or nose. Sometimes, larvae
penetrate deeply into the tissues. Intes-
tinal infestation can occur after eating
contaminated food. Preventative mea-
sures include keeping flies away from
food, covering open wounds, and ironing
clothes that have been dried outdoors.
Myiasis of the skin is treated by plac-
ing drops of oil over the swelling. The
larva comes to the surface, where it can
be removed with a needle. In deeper tis-
sues, surgery may be needed. Intestinal
myiasis is treated with a
laxative
.
myo
- A prefix denoting a relationship to
muscle (as in
myocarditis
).
myocardial infarction
Sudden death
of part of the
heart
muscle due to a
blockage in the blood supply to the
heart. The disorder is popularly known as
a heart attack. It is usually characterized
by severe, unremitting chest pain. Myo-
cardial infarction is the most common
cause of death in developed countries.
Men are more likely to have a heart
attack than women, and smokers are at
greater risk. Other risk factors include
increased age, unhealthy diet, obesity,
and disorders such as
hypertension
and
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