Flashcards in Radiology module 4 Deck (25):
A free radical is an ---- atom that exists with --- electron in its outer shell
---- are highly reactive and unstable elements
3 ways free radicals combine in order to gain stability?
Recombine and cause no changes
Combine with other free radicals
Combine with water or other molecules and form toxins (cellular changes)
2 theories of radiation injury
The direct theory of radiation injury says?
Free radicals directly contact critical areas of the body and causes cell damage
The Indirect theory of radiation injury says?
Cell damage is due to the formation of toxins from free radicals
Which type of radiation injury occurs more commonly?
Due to the high water content in body
A linear curve dose response says the response of the tissue is -----
to the dose?
Nonthreshold linear curve dose response says?
No matter how small the dose a response will occur
Threshold curve dose response says?
A response only occurs up to a certain point
Total dose is the ---- of radiation absorbed? And ---- damage occurs with larger tissue absorption
Factors that determine radiation injury?
Amount of tissue irradiated
Effects that are seen within minutes and are associated with large amounts of radiation over a short time are called?
Short term effects
Effects associated with small amounts of radiation given repeatedly over a long time are called?
Long term effects
Effects not seen in same person but in future generations are called?
Effects seen in the person irradiated are called?
Critical organs in head-neck region
Skin, thyroid, lens of eye, bone marrow
Radiosensitivity of cells is directly proportional to --- and ----
Also, Inversely proportional to -----
Degree of differentiation
Traditional system of measuring radiation?
SI system of measuring radiation
2 types of background radiation
Terrestrial ( earth/air)
3 sources of radiation exposure
Ways to reduce exposure to patients
Film speed (F)
Raise kvp to decrease exposure time
Digital systems decrease exposure by --- to --%