CT (
Computed Tomography) scans are also often referred to as CAT(
Computed Axial Tomography) scans although
CT is now preferred,
ostensibly because other orientations are now available. ( I am
personally convinced however that it
is because
healthcare professionals became sick of everyone making jokes involving
felines at every available opportunity).
I have created this node as separate from
cat scans since the contents of that node consist mainly of the
aforementioned attempts
at humour and the one 'factual' entry mistakenly equates
CT with
MRI
MRI (
magnetic resonance imaging) is an application of
NMR(
nuclear magnetic resonance) used for imaging soft tissues and is
a vastly different technique from CT which makes use of multiple
X-Rays to build up a computed image of the body.
A
CT scanner consists of a
ring device that surrounds the patient and contains a moveable
x-ray source with an electronic x-ray sensor on exactly the opposite side of the circle. X-rays are sent through the body from the source to the sensor from every
angle of orientation around the patient. A computer mathematically calculates the x-ray density of each of several million tiny locations in a given "slice" through the body and then displays the resulting
image for interpretation
The patient is often given a
contrast containing
iodine in order to enhance the resulting image. This may be
administered in a drink taken approximately an hour before the scan or via
intravenous injection at the time of the scan. In a small number of cases this can cause a mild
allergic reaction in the patient.
I had a
CT Scan this morning as a follow-up from my trip to
emergency ( see the
daylog). The procedure basically consists of lying
absolutely still and
holding
your breath for 20 seconds or so while the machine whirs, clicks and moves you
back and forth. I was given an
intravenous contrast which resulted in a very
peculiar feeling indeed. For approximately 30 seconds a
warm sensation washed through my body, starting at my head and shoulders and travelling down to
envelop my whole body. The closest I can come to describing it is that it was similar to an
adrenaline spike or strong
anxiety attack without the increased pulse rate,
hyperventilation or mental anguish. The
doctor had warned me about it and assured me it was completely normal, but I would have to disagree - it may be
usual but it was definitely not
normal.