Radiation Safety Flashcards
Which has a higher dose xray or CT
CT
What is the average patient dose
10-20 mSv
More detail requires what
More photons
Will all tissue receive the same exposure
Yes
What does a multi slice CT scan do
Scans and overlaps areas
Multi slice CT scan gives greater …….
Detail and dose
What is pitch
Relationship between scan / slice width
Tube rotation
What does it mean if the pitch is 1
Table and tube moved at the same time
No missing info
Overlapping info
What does it mean if the pitch is less than 1
Table moves MORE than scan width
Stretched coil
Missing info
What does it mean if the pitch is greater than 1
Table moves LESS than scan width
Small coils
What is the relationship of slice thickness if the pitch is less than 1
Slice thickness is larger than the patient movement
What will be the dose for thicker & fewer slices
Less patient dose & less detail
What happens if you increase pitch
Less image resolution
Less patient dose
Using a high kV results in
Lower mA
Less patient dose
Should you shield in CT
Yes
