Other Metals Flashcards
What is diagnostic imaging?
Exploiting the tissue penetration of gamma rays derived from nuclear decay
What is targeted therapy?
Exploiting the cellular toxicity of non-penetrating alpha and beta particles + secondary e-
What are the different types of particles?
Alpha
Beta
Positron
Proton
Neutron
Gamma ray
What is an alpha particle?
He nuclei consisting of 2 protons + 2 neutrons
What is a beta particle?
High-energy e-
What is a positron?
Particles with the same mass as an e- BUT with 1 unit of positive charge
What is a proton?
Nuclei of H atoms
What is a neutron?
Particles with a mass approx. equally to that of a proton BUT with no charge
What is the difference between alpha and beta particles?
Alpha is less energetic = hard to come out the body
Low energy = take much longer to decay
How does a beta particle become an e-?
Neutron spontaneously changes to proton = e- expelled out
What is a cyclotron?
Particle accelerator
Accelerates charged particles in a spiral path
What does a modern cyclotron do?
Accelerate negative ions created in plasma
Excess e- stripped off forming positive particles
What does medical cyclotrons do?
Produce proton beams to manufacture radioisotopes
What is PET?
Positive emission tomography
What is a SPECT?
Single photon emission computed tomography
Describe SPECT
Single photon emission + computer tomography mixed together
Uses 99m Tc
Describe PET
Emission of a proton that annihilates to a pair of identical gamma rays
What is zirconium-89 labelled antibodies?
New tool for molecular imaging in cancer patients
Why would you change the metal radioisotope in your diagnostic agent?
To change from a diagnostic positron emitting isotope to a therapeutic beta emitter
Describe Lutathera mode of action
IV injection
Conc into tumour sites (NET)
Binds to somatostatin receptors
Lutathera is internalised in NET cell
Delivers radiation
Radiation induces DNA strand breaks = cell death
