What is specific activity in nuclear medicine? Specific activity refers to the amount of radioactivity per unit mass of a radionuclide. It describes how much activity is present relative to the total quantity of that element. High specific activity means…
What is radiochemical purity? Radiochemical purity refers to the proportion of a radionuclide that is present in the desired chemical form. Even if the correct radionuclide is present (high radionuclidic purity), it may exist in multiple chemical species, not all…
What is radionuclidic purity? Radionuclidic purity refers to the proportion of the total radioactivity present in a preparation that comes from the desired radionuclide. It describes whether unwanted radioactive isotopes are present. In a Tc-99m generator eluate, radionuclidic purity means…
What is a radionuclide generator? A radionuclide generator is a device that allows a short-lived daughter radionuclide to be obtained from a longer-lived parent radionuclide. It acts as a portable source of radioactive material, enabling repeated extraction of the daughter…
How are radionuclides produced in a cyclotron? Radionuclides are produced in a cyclotron by accelerating charged particles, usually protons, to high energies and directing them at a stable target nucleus. The collision induces a nuclear reaction that transforms the target…
How are radionuclides produced in a nuclear reactor? Radionuclides are produced in a nuclear reactor primarily by neutron capture or nuclear fission. In neutron capture, a stable target nucleus absorbs a neutron and becomes radioactive. In fission production, heavy nuclei…
What is radionuclide production in nuclear medicine? Radionuclide production in nuclear medicine refers to the physical processes used to create radioactive isotopes for medical imaging and therapy. These isotopes are not naturally available in sufficient quantities and must be generated…
What is scatter correction and why is it needed in PET and SPECT? Scatter correction is the process of identifying and compensating for photons that have undergone Compton scatter before reaching the detector. Without correction, scattered photons are incorrectly assigned…
What is SUV and what affects it? SUV (Standardised Uptake Value) is a semi-quantitative measure used in PET imaging to estimate tracer uptake within a region, normalised for administered activity and patient size. It is most commonly used in FDG…
What determines quantitative accuracy in PET? Quantitative accuracy in PET refers to how closely measured activity concentrations reflect the true tracer concentration within tissues. It is determined by correct calibration, accurate attenuation and scatter correction, count statistics, spatial resolution effects,…
