Physics Flashcards
(119 cards)
EM radiation velocity?
3 * 10^8 m/s
What is the K shell binding energy of tungsten?
-69.5 keV
Relationship between Z and K shell binding energy
K shell binding energy is proportional to Z^2
Relationship between xray production and mA
linear increase
Relationship between xray production and kVp
Increasing kVp by 15% will double intensity of spectrum
What do you give to detect extrahepatic biliary atresia and how much
phenobarbitol
5 mg/kg/day
2 divided doses
3-5 days
Half life of gallium
78hours
Iso-osmolality iodinated contrast media
300 mOsm/kg
low-osmolality iodinated contrast media
600 mOsm/kg
high-osmolality iodinated contrast media
1200 mOsm/kg
human plasma
295 mOsm/kg
CTDIw
1/3 CTDI central + 2/3 CTDI peripheral
CTDIvol
CTDIw/Pitch
Window levels for Brain
W 80, L +40
Window levels for Lung
W 1500, L -400
Window levels for Abdomen
W 440, L +50
Window levels for Bone
W 1600, L +500
Adult Head Avg Dose CTDI
58 mGy, effective dose (1-2 mSv)
Adult Abd CTDI
18 mGy, effective dose (8-11 mSv)
Peds Abd CTDI
15 mGy
ACR “reference” dose, for which if they are above should be investigated:
CTDIvol for Head
75 mGy
ACR “reference” dose, for which if they are above should be investigated
CTDIvol for Adult Abd
25 mGy
ACR “reference” dose, for which if they are above should be investigated
CTDIvol for Peds
20 mGy
Embryo Dose in CT A/P
30 mGy