CREUTZFELDT-JAKOB DISEASE
PROCEDURE FOR CRANIOTOMY
Before the operation, all or part of
the patient’s scalp is shaved. After a
general anaesthetic has been given,
layers of skin, muscle, and membrane
are cut away from the skull at the
planned operation site and the bone
is cut with a saw (see below). The “lid”
of bone is then either folded back on
a “hinge” of muscle or removed
completely. The dura (the outermost
of the three membranes that surround
the brain) is then opened to reveal the
inner membranes and the brain.
Burr holes
A series of burr
holes is made. The
holes must be very
close together if the
bone is thick.
-
B u r r
- S k u ll
- D u ra
B u r r h o l e
G ig li’s s a w
F l a p o f s k u ll
h i n g e d b a c k
Gigli's saw
The bone between the burr holes is cut using
Gigli’s saw, which is passed between the burr
holes using a malleable saw guide.
B r a in
If the brain has been compressed, an
operation may be performed to sepa-
rate the fused skull bones.
craniotomy
The temporary removal of a section of
the skull to enable doctors to perform
an operation on the
brain
.
A craniotomy
may be carried out to take a sample of
tissue for analysis, remove a
tumour
,
or
drain an
abscess
or blood clot.
cranium
The part of the
skull
around the
brain
.
C-reactive protein
A protein produced by the body in res-
ponse to inflammation. The blood level
of this protein is measured to evaluate
treatment of inflammatory conditions.
cream
A thick, semi-solid preparation with
moisturizing properties, used to apply
medications to the skin.
creatine kinase
An
enzyme
(a protein that alters the rate
of a chemical reaction in the body)
found in muscle. After damage to mus-
cle cells, including those of the heart
muscle, creatine kinase leaks into the
blood. Increased levels of the enzyme
can be detected by diagnostic tests (see
muscle enzymes
) .
Different types of cre-
atine kinase exist in different types of
muscle. If blood tests show a raised
level of the form found in heart mus-
cle, this may indicate that a
myocardial
infarction
(heart attack) has occurred.
Raised levels of the form found in
skeletal muscles may indicate a range of
disorders, from muscle injury to dis-
eases such as
muscular dystrophy
.
creatinine
A waste product from chemical pro-
cesses in the muscles. The kidneys filter
it from the blood for excretion in
urine
.
creatinine clearance
A type of
kidney function test
in w hich
the level of
creatinine
in the blood and
the urine is measured. The blood level
is measured, then the urine is collected
and tested over 24 hours to measure
the level of creatinine being excreted.
The two levels are compared; if there is
a high level of creatinine in the blood
but a low level in the urine, it shows
that the
kidneys
are
not
effectively
clearing creatinine from the body.
crepitation
A crackling sound in the lungs (heard
through a
stethoscope
) due to a build-
up of fluid. (See also
auscultation
. )
crepitus
A grating sound or sensation caused by
rough surfaces inside the body rubbing
together. Crepitus may be felt or heard
when the ends of a broken bone rub
against each other, or when
cartilage
on
the surfaces of a joint has w orn away
due to
osteoarthritis
.
Faint crepitus may
be heard in the lung due to abnormali-
ties such as inflammation in
pneumonia
.
The term also describes the crackling
sound made when an air pocket under
the skin (see
emphysema, surgical
) ,
or an
area of gas
gangrene
,
is pressed.
cretinism
A
congenital
condition in infants that
is
characterized by
stunted
growth,
failure of norm al development,
learning
difficulties
,
and coarse facial features.
Cretinism occurs when the
thyroid gland
produces insufficient amounts of, or
fails to produce any, of the thyroid
hormone
thyroxine
at birth. However,
provided that the condition is recog-
nized early replacement therapy with
thyroxine can effect a cure. (See also
hypothyroidism.
)
Creutzfeldt-Jakob disease
A rare, progressive degenerative disease
of the
brain
.
Creutzfeldt-Jakob disease
(CJD) is thought to be caused by infec-
tion with a
prion
(a type of infectious
protein). A sim ilar agent causes scrapie
in sheep and
bovine spongiform enceph-
alopathy
(BSE) in cattle.
TYPES
One form of CJD largely affects middle-
aged or elderly people, and appears to
have no obvious cause. A second form
occurs in younger people. and this is
associated with contamination during
C
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