Imaging in Inflammatory Disorders and Infection Flashcards
What are the 4 types of molecular imaging?
Radionuclide
Positron Emission tomography
Magnetic Resonance
Optical
Why do gamma rays occur?
Due to radioactive decay or unstable isotopes.
What are radiopharmaceuticals made of?
Radioactive element
Pharmaceutical element
In an ideal isotope, what do you want the half life to be similar to?
Length of examination
In an ideal isotope, would you rather have alpha, beta or gamma emitter?
Gamma
In an ideal isotope, what should the energy of gamma rays be?
50-300keV
In an ideal isotope, where should the radionuclide be readily available at?
Hospital site
In an ideal isotope, what should it be easily bindable to?
Pharmaceutical component
In an ideal isotope, what should the radiopharmaceutical be simple to do?
Prepare
In an ideal isotope, when should the eliminated in similar half-time to?
Duration of examination
What is the movement of energy in a gamma camera? (4 step process).
Nuclear - Gamma EM - Light EM - Electrical
What 4 things can alter image quality?
Limitation to radiation dose
Collimator
Metal objects
Proximity of area
What does SPECT stand for?
Single Photon Emission Computed Tomography
SPECT is the CT version of what?
Nuclear medicine
What studies are SPECT routinely used for?
Brain
Cardiac
Lung
What does PET stand for?
Positron Emission Tomography
What is positron emission?
Proton - Neutron + positron
What is required for absolute quantitation in PET scanning?
Arterial sampling
What is the half life of 18F
110 minutes
What 7 places uptake FDG?
Brain Myocardium Stomach Liver Spleen Colon Urinary Tract
What is the main risk of radiation?
Ionising radiation which can induce fatal cancers.
What are the benefits of radiation?
Diagnosis
Management Change
Treatment
Why is technetium often used as a radionuclide?
It stays in an excited state for a long time.
In a gamma camera, what is placed over the image crystal?
Collimator
Why is there a lead shielding?
To stop gamma radiation getting out.
How are gamma cameras used in SPECT and PET?
Cameras are rotated around the area being scanned, shooting gamma rays and detecting ones that get absorbed.
