gamma waves. Those gamma waves are detected by
the PET scan and digitally transformed into a three
dimensional image on a display. (PET 2013) The
areas affected by the disease are made evident when
circulation is low or nonexistent. As the radiotracers are being broke down a PET scan can give
the clinician a real time function assessment of the
anatomy of interest. This is a huge advantage when
diagnosing many diseases. As you can see from this
illustration, the bottom left hand portion of the
epileptic image shows a lack of the radio-tracer
showing a decrease in circulation. (Brain 2014)
This will lead the clinician to focus their future
studies to that area in hopes to determine the cause.
An electrical signal is generated in the cell body near
the axon this signal is called the action potential. The
action potential is similar to an electrical signal in an
electronic device. In a device the electrons flow
along a wire, in a neuron the signal travels down the
axon till it reaches the axon terminal. That pulse of
energy stimulates the per-synaptic neuron to
generate the proper neurotransmitter. Once it is
released in to the synapse the post-synaptic nerve
accepts the signal. The signal then passes to the next
neuron. Transmission between neurons continues till
that message reaches its destination. (Sufflebeam
2008)
There are several devices used to diagnose epilepsy.
The most common being: he most common being:
Magnetic
Resonance
Imaging,
Electroencephalograph
EEG,
Computed
Tomography CT, and Positron Emission tomography
and most times they are used in conjunction. Today I
will be discussing the Positron Emission
Tomography (PET). I will explain the process of a
procedure, the technology behind the procedure, and
how a PET scan can help to diagnose epilepsy.
Before a PET scan can be accomplished a radio
pharmaceutical containing the radio tracer will need
to be administered. This is a chemical that will react
with the body in the specific area of interest. In the
case of epilepsy the radio-tracer called
fluorodeoxyglucose a solution similar to glucose in
the body just positively charged.
Brain cells breakdown the glucose positrons emitting
The PET scan uses detectors to gather the gamma
wave radiation from the radio-tracer emissions in
the patient. The detectors are collecting an analog
signal that is sent to the signal acquisition circuitry
(SAC). The SAC is responsible for converting
analog to digital signals. Those signals are sent to
the Energy Sorter Circuitry (ESC). In the ESC the
digital signals are analyzed and assessed for
irrelevant information and duplicated signals. Those
duplicate and irrelevant signals are filtered out. That
filtered signal is then sent to the Image Construction
Processor (ICP). The ICP is responsible for
constructing a signal used by the PET Processor to
display the results of the scan. Once the image is
displayed it can be manipulated to visualize the
target area. Allowing the clinician to properly
diagnose diseases.