Chapter 9 Stochastic Effects And Late Tissue Reactions

Question 1

Late effects are the long term results of radiation exposure, some examples of measurable delayed biologic damage are:

Answer 1

Cataracts
Leukemia
Genetic mutation

Question 2

Cataracts are considered to be a late tissue reaction that is __________.

Answer 2

Non random

Question 3

Leukemia and genetic mutations are viewed as delayed __________ or ________ consequences.

Answer 3

Stochastic
Random

Question 4

Science that deals with the incidence, distribution, and control of disease in a population

Answer 4

Epidemiology

Question 5

Consist of observations and statistical analysis of data, such as the incidence of disease within groups of people.

Answer 5

Epidemiologic studies

Question 6

Aka tumor I genesis is the formation of cancer.

Answer 6

Carcinogenesis

Question 7

Is the name used for a substantial group of diseases in which healthy cells have been transformed into nonstandard cells that divide uncontrollably.

Answer 7

Cancer

Question 8

The most significant late stochastic effect caused by exposure to ionizing radiation.

Answer 8

Cancer

Question 9

Is demonstrated graphically through a curve that maps the observed effects of radiation exposure in relation to the dose of radiation received.

Answer 9

Radiation dose response relationship

Question 10

The DR curve is either ______(straight line) or _______ (curved to some degree), and it depicts either a __________ dose or a ___________ dose.

Answer 10

Linear
Nonlinear
Threshold
Non-threshold

Question 11

Defined as a point or level which a response or reaction to an increasing stimulation first occurs

Answer 11

Threshold

Question 12

_________ effects begin to occur only when the threshold dose is reached.

Answer 12

Biologic

Question 13

_____ relationship indicated that a radiation absorbed dose of any magnitude has the capability of producing biologic effect.

Answer 13

Non threshold

Question 14

A ____________ , biologic effect responses will be caused by ionizing radiation in living organisms in a directly proportional manner at any dose above zero.

Answer 14

Linear non threshold

Question 15

_________ proclaims that no radiation dose can be considered absolutely “safe”, with the incidence of the biologic effects increasing directly with the magnitude of the absorbed dose

Answer 15

Linear non threshold (LNT)

Question 16

The Biological Effects of Ionizing Radiation (BEIR) studied atomic bomb survivors concluded that most stochastic effect and hereditary effect at ______ dose levels from ____ LET radiation.

Answer 16

Low
Low

Question 17

Low dose from low LET radiation used in diagnostic radiology, appear to follow a ________________.

Answer 17

Linear quadratic non threshold dose response curve.

Question 18

Implies that the equation that best fits the data has components that depend on dose to the first power and also on dose squared.

Answer 18

Linear quadratic

Question 19

In 1990, the BEIR committees revised risk estimates indicated that the risk from radiation exposure was about ____ to _____ times greater than previously projected.

Answer 19

3 to 4

Question 20

The use of a __________ curve of radiation dose response is used for most type of cancers.

Answer 20

Linear non threshold

Question 21

The linear quadratic non threshold DR curve displays a more __________dose response outcome of low level radiation.

Answer 21

Conservative

Question 22

What health concerns are presumed to follow the linear quadratic non threshold curve (LQNT).

Answer 22

Leukemia
Breast cancer
Heritable damage

Question 23

Acute reactions from significant radiation exposure, such as skin erythema and hematologic depression, may be demonstrated graphically through the use of a radiation __________.

Answer 23

Linear threshold dose response curve

Question 24

_________ curve of the radiation dose response relationship is generally employed in radiation therapy to demonstrate the high dose cellular response to the radiation absorbed doses within specific tissue such as skin, the lens of the eye and various types of blood cells.

Answer 24

The sigmoid, or S shaped (non linear), threshold curve.

Question 25

The sigmoid curve, the _______ of the curve indicated that limited recovery occurs at lower radiation doses and at the highest radiation doses the curve gradually levels off and then veers downward because the effected living specimen or tissue dies before the observable effect appears.

Answer 25

Tail

Question 26

When living organisms that have been exposed to radiation sustain biologic damage, the effects of this exposure are classified as__________

Answer 26

Somatic effects

Question 27

The classification of somatic effects may be subdivided into: __________ and ________

Answer 27

Stochastic effect and tissue reactions

Question 28

In ________ effects, the probability that the effect occurs depends upon the received dose, but the severity of the effect does not.

Answer 28

Stochastic

Question 29

The occurrence of a cancer is an instance of a _________ or random somatic effect.

Answer 29

Stochastic

Question 30

A __________ effect is an effects in the offspring of the individual who was irradiated.

Answer 30

Non somatic

Question 31

Example of a __________ effect is the irradiation of an individual’s genetic material (sperm of eggs) leading to a genetic malformation in offspring.

Answer 31

Non somatic

Question 32

Are consequences of radiation exposure that appear months or years afterwards.

Answer 32

Late somatic effects

Question 33

Late effects may be either ________ or ______ reactions.

Answer 33

Stochastic
Tissue

Question 34

Cataract formation, fibrosis, organ atrophy, loss of parenchyma cells, reduced fertility and sterility are examples of _______ reactions.

Answer 34

Late tissue

Question 35

Are effects of radiation on the embryo-fetus in utero that depend on the fetal stage of development and radiation dose received.

Answer 35

Teratogenic effects

Question 36

Embryonic, fetal, or neonatal death
Congenital malformations, decreased birth weight, disturbances in growth and of development, increased stillbirths, infant mortality, childhood malignancy, childhood mortality are examples of what effects.

Answer 36

Teratogenic effects

Question 37

Cancer and genetic (hereditary) effects are examples of ______ effects.

Answer 37

Stochastic

Question 38

______ effects such as the occurrence of cancer are generally determined at the time of irradiation.

Answer 38

Stochastic

Question 39

No conclusive proof currently exists that low LET ionizing radiation absorbed doses below ______ Gy (10 rads) causes significant increase in the risk of malignancy

Answer 39

0.1

Question 40

Sources of such _______ radiation include the following:
X-ray and radioactive materials used for diagnostic purposes.
Employment related exposures in medicine and industry
Natural background exposure

Answer 40

Low level

Question 41

Low level low LET radiation dosage has been defined as an equivalent dose of ______ or less delivers over a short time.

Answer 41

0.1 Sv