Instruments in Nuclear
Medicine
Department of Nuclear Medicine
Renji Hospital
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Principle of Detection of Radiation
►Ionization
►Excitation
►Chemical
mechanism
►Annihilation radiation
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Detector
►Ionization
detector
►Scintillation detector
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In vitro radioassay
►γ
counter ( well-type γcounter)
►βcounter ( liquid scintillation
counter)
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Radionuclide Imaging
PET
SPECT
γ camera
scintillation
scanner
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γ Camera
collimator
crystal
γ camera
photomultiplier
pulse height analyzer
electric element
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Computed Tomography (CT)
Computed
Tomography
（CT）
Emission
Computed
Tomography
(ECT)
Transmission
Computed
Tomography
(TCT)
Single Photon
Emission Computed
Tomography (SPECT)
Positron Emission
Tomography (PET)
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Single Photon Emission Computed
Tomography (SPECT)
Single Photon Emission Computed Tomography
 Filtered backprojection, FBP
 Quality Control (QC) on SPECT imaging
• Field uniformity and correction
• Determination and correction of center of rotation
• X and Y gain calibration pixels
• QC of collimator
• etc.
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SPECT
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SPECT
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SPECT
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SPECT
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SPECT
13
How PET Works
► A short-lived
radioactive
substance such as 18F is injected
into the bloodstream as glucose
The
► Radionuclides decay by
emitting a positron, which
would annihilate with an
electron in the tissue to produce
gamma rays
► Gamma rays fly off in opposite
directions into the detectors.
enables the location of the
original electron to be
pinpointed
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Positron Emission Tomography
(PET)
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Positron Emission Tomography
(PET)
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Micro PET / CT
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Fusion of Images
►PET-CT
►SPECT-CT
►PET-MRI
►SPECT-MRI
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Fusion of Images
Image
Fusion
with CT
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Fusion of Images
Image
Fusion
with MR
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Radiopharmaceutical
Radiopharmaceuticals have been defined
as products labeled with one or several
radioactive atoms, which are used for
the purpose of diagnosis or therapy
Iodine-131, 131I and Xenon-133, 133Xe, etc
99mTc-ECD, 99mTc-HSA, 99mTc-MAA, 99mTcRBC, etc
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Production of Radionuclides
► Reactor-produced radionuclide
A-1 X + γ
X
+
n
Z
Z
133Xe, 99Mo, 131I, etc
► Cyclotron-produced radionuclide
beta-plus decay; electron capture decay
201Tl, 67Ga, 123I, 111In, 18F, 11C, etc
► Generator-produced radionuclides
68Ga, 99mTc, 113mIn
A-1
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Properties of the Ideal Diagnostic
Radiopharmaceutical
► Type
of emission
pure gamma-ray emitter, decaying by either
electron capture or isomeric transition
► Energy
100kev~250kev
► Availability
► Target-to-nontarget ratio
► Effective half life
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Properties of the Ideal
Therapeutic Radiopharmaceutical
►Type
of emission
pure beta-minus emission
►Energy
(β emitter >1MeV)
►Target-to-nontarget ratio
►Effective half life
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Positron Radiopharmaceutical
►Positron
nuclides
11C, 13N, 15O, 18F, 62Cu, 68Cu, 82Rb, 75Br,
38K, 73Se, 94mTc
►Positron Radiopharmaceutical
18FDG, 6- [18F]-L-DOPA, 11C-DOPA,
18F-MET, 11C-Tyr, 18F-FLT, etc
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QA of Radiopharmaceutical
►
Radionuclide purity
► Radiochemical purity
► Chemical purity
► Sterility
► Apyrogenicity
► Absence of foreign particulate matter
► Particle size (if appropriate)
► pH
► Biological distribution
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Review
►What
is radiopharmaceutical?
►What is SPECT?
► What
is PET? How it works?
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Review
► What
properties should ideal diagnostic and
therapeutic radiopharmaceutical have?
► Where are radionuclides producted from?
►What
aspects does QA involve using
radiopharmaceutical?
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