Complete Solutions
(M) minimal dose reported Correct Answers less then 1 mrem
inner badge weighted 1.5x(inner) + (0.04x)(outer)
1 ampere = Correct Answers 1 coulomb/second
1 Coulomb = ________ electrons Correct Answers 6.25 x 10
^18 electrons passing by in one second
ABC uses brightness sensor to adjust....... Correct Answers kV
and mA
absorbed dose is also known as Correct Answers equivalent
dose
absorbed dose is measured in_____? Correct Answers Rad and
Gy
absorbed energy equation Correct Answers absorbed energy=
energy transferred- energy escaped
acute radiation dose Correct Answers high dose delivered over
a short period of time
can be 10 rads+ and is associated with acute radiation syndrome
acute radiation syndrome (LD50) Correct Answers several
determinants factors; cell death in many organs
- 70 rads (0.7 Gy) to entire body and the exposure occurs in a
short amount of time
,- ex: nuclear reactor accident
AEC controls..... Correct Answers mAs
AERC Correct Answers automatic exposure rate control; pretty
much the same thing as ABC, it control the exposure rate of the
patient but it has digital detectors ( electrons in
capacitors)instead of an II with a brightness sensor
AERC uses what instead of a brightness sensor Correct Answers
digital detector ( electrons in capacitors)
after 16 weeks post conception what is the dose limit? Correct
Answers 0.5-0.7 Gy
air gaps Correct Answers 10-15 cm, usually used in mag.
projections (mammo)
Air Kerma (Gya) Correct Answers J/kg and Gray
kinetic energy released in matter
air kerma units Correct Answers J/kg and Gray
1 Gray= 114 Roetgen
1 Roetgen= .88 Rad
Although NCRP recommends 2mm Pb for lead glasses, what
does the industry usually provide? Correct Answers 0.75mm
shielding with the side shields at 0.35mm
annual limit to extremities Correct Answers 5000mRem= 500
mSv
,annual limit to lens Correct Answers 15000mRem= 150 mSv
annual whole body dose limit Correct Answers 500 mRem= 50
mSv
are stitch holes on aprons okay? Correct Answers YES
as grid ratio increases? Correct Answers technique increases,
dose increases and scatter decreases
as photon energy increases there is more Correct Answers
penetration and a decrease in tissue interactions
at what time will the fluoro timer go off? Correct Answers after
5 mins
attenuation Correct Answers the drop of intensity of the beam
due to absorption and scatter
attenuation equation Correct Answers I= Io e^ (-ux)
initial energy x e^( attenuation factor x tissue thickness)=
resulting energy
initial energy- resulting energy= absorbed energy
Bergonie-Tribondeau law Correct Answers cells that are rapidly
dividing , undifferentiated and have a long mitotic cycle are
more sensitive to radiation
, bone marrow syndrome Correct Answers destruction of the
bone marrow, immune system failure, decrease in RBC, internal
bleeding
bremsstrahlung interaction Correct Answers 99% heat, 1% x-
ray
aka braking radiation, cathode electrons hit anode electrons.
Electron that are closer to the nucleus slow down more and lose
more energy but create higher energy electrons. Electrons that
are farther away slow down less, lose less energy and create low
energy x-rays. They retain enough energy to keep having more
interactions
(electrons are more likely to hit the outer rim of the anode)
broken grids Correct Answers due to we and tear and the lead
strips get smushed together
bucky factor Correct Answers determines how much we must
increase our technique with a grid
bucky factor equation Correct Answers B= incident radiation/
transmitted radiation
can cumulative dose also be considered a sentinel event? Correct
Answers if a pt gets irradiated in the same field for different
exams over the course of 6 months to a year and all together
they exceed the max dose, it can be considered a sentinel event
carcinogenesis Correct Answers development of cancer