Transcript The Physics of Positron Emission Tomography

PET Scans
Lesson Objectives:
Describe how PET scans are used
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Revision..
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Name the different types of nuclear radiation
that can occur.
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What is anti-matter?
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What happens when an anti-particle and a
particle meet each other?
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+ Decay
Neutron-deficient isotopes can decay by emitting
positrons
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Neutron retained by the nucleus
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positron
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Net effect: one
proton
replaced by
• neutron
• positron
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Non-invasive Medical Imaging
Techniques
CAT
CAT –
(Computerised
Tomography) uses X-rays
MRI
X-Ray
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MRI (Magnetic
Resonance
Imaging) - uses a
magnetic field
Positron Emission Tomography
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Do not show anatomy of
the body
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Only processes which are
going on
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Positron (+) Decay
Nucleus
Neutrons
18F-FDG
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emits positrons
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Protons
Electrons
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PET Imaging
1.
Inject radioisotope
2.
Measure gamma-ray
emissions from
isotope
3.
Sensors detect the
gamma rays
4.
Computes create a
picture to show the
position of the source
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Task
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The following sentences on your worksheet
have been jumbled up. Cut them out and
rearrange them to describe how a PET scan
works.
When you are sure they are in the correct
order stick them in your book.
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