The TD 5/5 for the whole brain using standard fractionation is approx:
45 Gy
The period of organogenesis normally occurs between the _______ weeks of fetal development.
Second through Eighth
The phase of the cellular division most resistant to radiation is the _______ phase.
S
The immediate symptoms that appear after an acute radiation exposure are called _________ symptoms.
Prodromal
Nausea is associated with the __________ syndrome.
Prodromal
The period over which radiation is delivered is referred to as the _________.
Protraction
Erythematous skin reactions during fractionated radiation therapy are seen as a result of _____________ in the area.
Vascular dilation
__________ is an effect of radiation on DNA.
Cross-linking
In linear or nonlinear threshold dose-response curves, the response ___________ (may/may not) occur at low doses.
May not
The average energy deposited per unit of path length to a medium by ionizing radiation as it passes through that medium descibes:
Linear Energy Transfer
The four R's of radiobiology are:
Repair
Reoxygenation
Repopulation
Redistirbution
Lung cancer would be classified as a _________ radiation response.
Stochastic
The standard radiation used to determine RBE is:
250 keV x-ray
Without medical intervention, a person exposed to a single whole body dose of _____ may die within 10 days.
10 Gy
Xerostomia can become permanent after doses of:
40 Gy
Tissue injury ________ as the volume of tissue irradiated increases.
Increases
An anticipated response to radiation dose above 55 Gy to the colon is:
Fistula
Regarding non stochastic effects, effects ________ (are/are not) seen in future generations and the _________ of effects is related to dose.
Are NOT
Severity
The part of the cell between the membrane and the nucleus is known as the:
Cytoplasm
The primary function of the cell nucleus is:
Housing DNA and RNA
The main objectives of radiation protection include prevention of radiation-induced _________ effects and production of radiation-induced _________ effects.
Deterministic & Stochastic
Somatic effects are limited to the __________ individual.
Exposed
Ellis' NSD formula is _________ and does not accomodate:
Total dose = (NSD) T0.11 N0.24
Different tissue types with varying sensitivity
Regarding the tissue tolerance, as the volume of tissue increases, the tolerance dose _________.
Decreases
Lethal damage is _________ and leads to ___________.
Irreparable
Cell Death
________ phase takes place between G1 and G2.
Synthesis
A cell survival curve usually has a ________ and _________.
Shoulder
Straight portion
Which dose effect curve implies that if radiation dose is doubled, the biological effect will be doubled?
Linear
Cellular growth and development is called:
Proliferation
According to the current recommendations, the guidance levels for cumulative exposures for a 30 year old occupational worker with 3 years of experience.
300 mSv
(10 mSv X age in years)
It is recommended that radiation exposure to the fetus should not exceed ______ for the entire gestation period.
0.5 rem
The roentgen is a unit of measurement that specifies the __________ of air by x-ray or gamma radiation.
Ionization
The term quality factor (Q) varies with _____________.
Different types of radiation
Dose equivalent is measured in units of:
Sievert (rem)
The organization in the US that is principally responsible for recommending radiation dose limits is the:
NRC
The annual radiation dose to the lung from radon is estimated to be:
200 mrem/year
The annual dose limit for the occupational worker's lens is:
15 rem
(150 mSv)
TRUE/FALSE: Maximum exposure rate at a specific distance from a patient following insertion of radioactive sources can be measured with TLD's.
False
should be measure with an ion chamber
TRUE/FALSE: The requirement for barrier protection in walls/ceiling from primary radiation is reduced when there is a beam stopper on the treatment unit.
True
Cataract formation is an example of a ____________ effect.
Deterministic
The amount of energy absorbed in a medium is expressed in units of:
Gray (Gy)
The quantity directly measured by the TLD is:
Absorbed dose
The radioactive source inventory room should have a sign that reads:
Caution Radioactive Material
The _________ describes how much the primary beam is in use.
Workload
What is the equation to find the half value layer from linear attenuation coefficient or vice versa?
Patients undergoing thyroid ablation with I131 should not be released to leave the facility until survey meter readings reach less than _______ at ______ meter.
less than 5 mrem/hr at 1 m
A monthly radiation exposure report says an employee received 0.5 Sv. If the source of the exposure were determined to be gamma radiation, the translation to absorbed dose would be:
0.5 Sv = 0.5 Gy
Sv = Gy x QF
How many HVL's reduce transmission to 2%?
5.6 HVL's
Three tenth value layers reduce transmission to:
0.1%
The shielding around stored radioisotopes must be adequate to reduce radiation levels to less than _____ mrem/hr at 1 meter.
less than 2 mrem/hr at 1 m
What is the transmission formula?
I = final intensity
Io = Original Intensity
List the half-life, source form and applications of Cesium 137:
Cesium 137
30 years
Tubes, needles
LDR intracavitary, interstitial
List the half-life, source form and applications of Iridium 192: