Fluoroscopy ARRT Exam Study guide
- ANS-
(M) minimal dose reported - ANS-less then 1 mrem
inner badge weighted 1.5x(inner) + (0.04x)(outer)
1 ampere = - ANS-1 coulomb/second
1 Coulomb = ________ electrons - ANS-6.25 x 10 ^18 electrons passing by in one
second
ABC uses brightness sensor to adjust....... - ANS-kV and mA
absorbed dose is also known as - ANS-equivalent dose
absorbed dose is measured in_____? - ANS-Rad and Gy
absorbed energy equation - ANS-absorbed energy= energy transferred- energy
escaped
acute radiation dose - ANS-high dose delivered over a short period of time
can be 10 rads+ and is associated with acute radiation syndrome
acute radiation syndrome (LD50) - ANS-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..... - ANS-mAs
AERC - ANS-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 - ANS-digital detector ( electrons in
capacitors)
after 16 weeks post conception what is the dose limit? - ANS-0.5-0.7 Gy
,air gaps - ANS-10-15 cm, usually used in mag. projections (mammo)
Air Kerma (Gya) - ANS-J/kg and Gray
kinetic energy released in matter
air kerma units - ANS-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? - ANS-0.75mm shielding with the side shields at 0.35mm
annual limit to extremities - ANS-5000mRem= 500 mSv
annual limit to lens - ANS-15000mRem= 150 mSv
annual whole body dose limit - ANS-500 mRem= 50 mSv
are stitch holes on aprons okay? - ANS-YES
as grid ratio increases? - ANS-technique increases, dose increases and scatter
decreases
as photon energy increases there is more - ANS-penetration and a decrease in tissue
interactions
at what time will the fluoro timer go off? - ANS-after 5 mins
attenuation - ANS-the drop of intensity of the beam due to absorption and scatter
attenuation equation - ANS-I= Io e^ (-ux)
initial energy x e^( attenuation factor x tissue thickness)= resulting energy
initial energy- resulting energy= absorbed energy
Bergonie-Tribondeau law - ANS-cells that are rapidly dividing , undifferentiated and
have a long mitotic cycle are more sensitive to radiation
bone marrow syndrome - ANS-destruction of the bone marrow, immune system failure,
decrease in RBC, internal bleeding
,bremsstrahlung interaction - ANS-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 - ANS-due to we and tear and the lead strips get smushed together
bucky factor - ANS-determines how much we must increase our technique with a grid
bucky factor equation - ANS-B= incident radiation/ transmitted radiation
can cumulative dose also be considered a sentinel event? - ANS-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 - ANS-development of cancer
Cardiovascular and CNS syndrome - ANS-collapse of circulatory system and fluid
collection in the brain
cataract formation - ANS-loss of transparency of the lens of the eye
characteristic interactions - ANS-made 2 ways
1)cathode electrons hit anode electrons
2) PE effect from x-ray to electron interactions
chronic radiation dose - ANS-dose received over a long period of time, usually in small
doses and can be from background radiation
coherent scatter - ANS-aka Thompson scatter, Rayleigh scatter or classical scatter.
x-ray is absorbed by entire atom and is sent off in another direction with no energy loss
Compton effect - ANS-hits the outer electron, incomplete transfer of energy, electron
released and a low energy xray is deflected
Compton is dependent on - ANS-energy level ( the higher it is, the greater probability of
occurrence), electrons/ gram
, contrast to noise ratio - ANS-[signal ( area 1) - signal (area 2)] / noise
crossed grids - ANS-2 sets of parallel lead , cleans up scatter in both direction and
cannot angle because of grid cutoff
crossed grids - ANS-2 sets of parallel lead strips, cleans up scatter in both direction but
you cannot angle with it because it will result in grid cutoff
damage to the eye is what type of effects? - ANS-deterministic
DAP- dose area product - ANS-DAP Rad cm^2= dose x area irradiated
it takes in account entire area of the x-ray beam
dental unit minimum lead shielding - ANS-0.25 mm
digital subtraction process - ANS-mask image is created, contrast injected , another
image taken, initial mask image subtracted
direct mode - ANS-x-ray hits the DNA
does coherent scatter result in patient dose? - ANS-No, this reaction only causes
excitation of the atoms shells, but there is not energy transfer nor does the x-ray lose
energy ( isotropic)
dose for epilation and erythema to worsen - ANS-500-1000 rads
dose for moist/ dry desquamation ( skin peels off) to occur and lead to dermal necrosis -
ANS-15 Gy +
dose for permanent epilation and skin peels - ANS-10-15 Gy
dose for transient epilation - ANS-300 Rads
dose for transient erythema - ANS-200 Rads
dose limit for rad workers in a year? - ANS-5000 mRem/yr
dynamic range - ANS-range of useful exposures on the detector before the detector
saturates
- ANS-
(M) minimal dose reported - ANS-less then 1 mrem
inner badge weighted 1.5x(inner) + (0.04x)(outer)
1 ampere = - ANS-1 coulomb/second
1 Coulomb = ________ electrons - ANS-6.25 x 10 ^18 electrons passing by in one
second
ABC uses brightness sensor to adjust....... - ANS-kV and mA
absorbed dose is also known as - ANS-equivalent dose
absorbed dose is measured in_____? - ANS-Rad and Gy
absorbed energy equation - ANS-absorbed energy= energy transferred- energy
escaped
acute radiation dose - ANS-high dose delivered over a short period of time
can be 10 rads+ and is associated with acute radiation syndrome
acute radiation syndrome (LD50) - ANS-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..... - ANS-mAs
AERC - ANS-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 - ANS-digital detector ( electrons in
capacitors)
after 16 weeks post conception what is the dose limit? - ANS-0.5-0.7 Gy
,air gaps - ANS-10-15 cm, usually used in mag. projections (mammo)
Air Kerma (Gya) - ANS-J/kg and Gray
kinetic energy released in matter
air kerma units - ANS-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? - ANS-0.75mm shielding with the side shields at 0.35mm
annual limit to extremities - ANS-5000mRem= 500 mSv
annual limit to lens - ANS-15000mRem= 150 mSv
annual whole body dose limit - ANS-500 mRem= 50 mSv
are stitch holes on aprons okay? - ANS-YES
as grid ratio increases? - ANS-technique increases, dose increases and scatter
decreases
as photon energy increases there is more - ANS-penetration and a decrease in tissue
interactions
at what time will the fluoro timer go off? - ANS-after 5 mins
attenuation - ANS-the drop of intensity of the beam due to absorption and scatter
attenuation equation - ANS-I= Io e^ (-ux)
initial energy x e^( attenuation factor x tissue thickness)= resulting energy
initial energy- resulting energy= absorbed energy
Bergonie-Tribondeau law - ANS-cells that are rapidly dividing , undifferentiated and
have a long mitotic cycle are more sensitive to radiation
bone marrow syndrome - ANS-destruction of the bone marrow, immune system failure,
decrease in RBC, internal bleeding
,bremsstrahlung interaction - ANS-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 - ANS-due to we and tear and the lead strips get smushed together
bucky factor - ANS-determines how much we must increase our technique with a grid
bucky factor equation - ANS-B= incident radiation/ transmitted radiation
can cumulative dose also be considered a sentinel event? - ANS-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 - ANS-development of cancer
Cardiovascular and CNS syndrome - ANS-collapse of circulatory system and fluid
collection in the brain
cataract formation - ANS-loss of transparency of the lens of the eye
characteristic interactions - ANS-made 2 ways
1)cathode electrons hit anode electrons
2) PE effect from x-ray to electron interactions
chronic radiation dose - ANS-dose received over a long period of time, usually in small
doses and can be from background radiation
coherent scatter - ANS-aka Thompson scatter, Rayleigh scatter or classical scatter.
x-ray is absorbed by entire atom and is sent off in another direction with no energy loss
Compton effect - ANS-hits the outer electron, incomplete transfer of energy, electron
released and a low energy xray is deflected
Compton is dependent on - ANS-energy level ( the higher it is, the greater probability of
occurrence), electrons/ gram
, contrast to noise ratio - ANS-[signal ( area 1) - signal (area 2)] / noise
crossed grids - ANS-2 sets of parallel lead , cleans up scatter in both direction and
cannot angle because of grid cutoff
crossed grids - ANS-2 sets of parallel lead strips, cleans up scatter in both direction but
you cannot angle with it because it will result in grid cutoff
damage to the eye is what type of effects? - ANS-deterministic
DAP- dose area product - ANS-DAP Rad cm^2= dose x area irradiated
it takes in account entire area of the x-ray beam
dental unit minimum lead shielding - ANS-0.25 mm
digital subtraction process - ANS-mask image is created, contrast injected , another
image taken, initial mask image subtracted
direct mode - ANS-x-ray hits the DNA
does coherent scatter result in patient dose? - ANS-No, this reaction only causes
excitation of the atoms shells, but there is not energy transfer nor does the x-ray lose
energy ( isotropic)
dose for epilation and erythema to worsen - ANS-500-1000 rads
dose for moist/ dry desquamation ( skin peels off) to occur and lead to dermal necrosis -
ANS-15 Gy +
dose for permanent epilation and skin peels - ANS-10-15 Gy
dose for transient epilation - ANS-300 Rads
dose for transient erythema - ANS-200 Rads
dose limit for rad workers in a year? - ANS-5000 mRem/yr
dynamic range - ANS-range of useful exposures on the detector before the detector
saturates
