QC

Question 1

Centering- SID

Answer 1

Actual center of the x-ray beam must align to the centering indicator by 1% of the SID

Question 2

Distance- SID

Answer 2

Actual SID must be within +/- 2% of the indicated SID

Question 3

Potential effects of the SID not being what the indicated SID is:

Answer 3

-Incorrect technique
-Increased patient dose
-Overexposed on IR

Question 4

Collimation- SID

Answer 4

The light field must align with the x-ray field collimation +/- 2% of the SID

Question 5

Exposure Time and AEC

Answer 5

Actual exposure time must be within +/- 5% of indicated exposure time

Question 6

AEC Testing

Answer 6

-Done by making exposure using AEC on different thickness of aluminum
-Using the same technique and AEC by adding aluminum layers you should get the same receptor exposure

Question 7

kVp Calibration

Answer 7

The actual kVp must be within +/-5% of assigned kVp

Actual kVp>assigned kVp= Increased patient dose=decreased image quality

Question 8

kVp Reproducibility

Answer 8

(Exposure 2-Exposure1)/Exposure 1=Percentage

-Exposure values for identical technical parameters should be within +/-5%
-Same mA, Same kVp, Same exposure time

Question 9

Exposure Linearity

Answer 9

Microgray/mAs
then
(Exposure 1 mAs-Exposure 2 mAs)/Exposure 1 mAs= Exposure linearity

-Exposure per mAs(microgray/mAs) should not change more than 10% between mA stations
-When we change one mA to the next on the machine results should not be different by more than 10%