1420-1421 / 2605
Two types of late effects of irradiation
•
Deterministic (non-stochastic) effects
–
Severity increases with dose. There is a threshold !
e.g
tissue fibrosis, ulceration, perforation, necrosis, loss of organ function
(
xerostomia, nephrosclerosis
), cataracts
–
Mechanism involves effects (often cell kill) on many
cells
•
Stochastic effects
–
No threshold, probability increases with dose but
severity is independent of dose
e.g. cancer and genetic effects