Safety
PET scanning is non-invasive, but it does involve exposure to ionizing radiation. The total dose of radiation is significant, usually around 5–7 mSv. However, in modern practice, a combined PET/CT scan is almost always performed, and for PET/CT scanning, the radiation exposure may be substantial—around 23–26 mSv (for a 70 kg person—dose is likely to be higher for higher body weights). When compared to the classification level for radiation workers in the UK of 6 mSv, it can be seen that use of a PET scan needs proper justification. This can also be compared to 2.2 mSv average annual background radiation in the UK, 0.02 mSv for a chest x-ray and 6.5–8 mSv for a CT scan of the chest, according to the journal Chest and ICRP. A policy change suggested by the IFALPA member associations in year 1999 mentioned that an aircrew member is likely to receive a radiation dose of 4–9 mSv per year.
Read more about this topic: Positron Emission Tomography
Famous quotes containing the word safety:
“A lover is never a completely self-reliant person viewing the world through his own eyes, but a hostage to a certain delusion. He becomes a perjurer, all his thoughts and emotions being directed with reference, not to an accurate and just appraisal of the real world but rather to the safety and exaltation of his loved one, and the madness with which he pursues her, transmogrifying his attention, blinds him like a victim.”
—Alexander Theroux (b. 1940)
“The Declaration [of Independence] was not a protest against government, but against the excess of government. It prescribed the proper role of government, to secure the rights of individuals and to effect their safety and happiness. In modern society, no individual can do this alone. So government is not a necessary evil but a necessary good.”
—Gerald R. Ford (b. 1913)
“Perhaps having built a barricade when you’re sixteen provides you with a sort of safety rail. If you’ve once taken part in building one, even inadvertently, doesn’t its usually latent image reappear like a warning signal whenever you’re tempted to join the police, or support any manifestation of Law and Order?”
—Jean Genet (1910–1986)