Best for broken bones, dentistry & some soft tissues.
Photographic film and xray
Generator. Rays expose film and
turn it black.
No rays reached paper = white
(bones and metal show up as
white)
Xrays are ionising
and exposure has to
be kept to a
minimum.
Xrays have contrasting agents that
can boost attenuation coefficient of
soft tissues - better distinguishing of
soft tissues - in the form of an artifical
contrast medium
In the digestive system, barium is
given containing barium sulfate to
identify stomach/intestinal
blockages.
relatively Cheap
CAT Scanning - computer tomography
Produces more detailed picture than
xray by putting the image together
using a computer.
Consists of a rotating x-ray source and a ring of
detectors surrounding the patient. Data
produced builds up a detailed cross sectional
image
CAT scan has 100X more ionising radiation
than xray to be built up into a 3D
image
This means that the patient is limited
to the amount of CAT scans they can
have, and it also puts the
radiographer at risk.
MRI scanning - magnetic
resonance imaging
Carries no known risks
Loud
Not good for young
children/claustrophobes
Some patients may need
sedation or restraint
Ring-shaped
electromagnets that line
the MRI unit
When switched on
protons in the body
(from hydrogen atoms)
line up in the
electromagnetic field
once lined up a radio frequency is emitted which
disturbs proton alignment and causes them to rotate,
emitting tiny radio frequency signals.
Expensive - maintenance of
machine and supply of helium to
be made into liquid helium to
keep the electromagnetic coil cold
is very costly.
Small radio frequency coil is
used to cover relevant parts
of the body to pick up signals
from resonating protons,
which allows them to then be
converted into an image
Not appropriate for
patients with metal
implants
Term used to describe any
method used to view the inside of
the body without invasive surgery
Ultra sound scanning
Uses high frequency sound
emitted from a transceiver
unit, which rebounds off of
tissue
Gel has to be used so that air gaps do not
disrupt the signal
Cheap - only
needs one unit
Means it is
accessible to
LEDCs.
Real-time imaging
Useful in prenatal scans as is can
detect deformities without invasive
testing which could be harmful to the
baby