Medical physicist QC

Question 1

Spatial Resolution

Answer 1

Purpose: measures limiting spatial resolution that indicates detector performance (ability to distinguish between 1 adjacent objects)
Frequency: annually MEE new units, after service

Question 2

AEC

Answer 2

Purpose: Assess AEC, verify consistency in detector SNR in different breast thickness
Frequency: MEE, after service, new equip

Question 3

Avg glandular dose

Answer 3

Purpose: measures ESE for avg pt (4.2 cm, 50% glandular 50% fatty breast)
Frequency: MEE, after service, new equip

Question 4

AWS/RWS

Answer 4

Purpose: makes sure all monitors are clean. Calibrated correctly w/ brightness & contrast
Frequency: MEE, after service, new equip

Question 5

Eval of sites tech QC program

Answer 5

Purpose: ensure all tech QC are being performed at correct times, identify areas where image quality/QC can be improved
Frequency: annually

Question 6

HVL

Answer 6

Purpose: ensures HVL of xray beam will decrease pt breast dose w/o decreasing contrast
Frequency: annually, MEE, after service

Question 7

KVP reproducibility/accuracy

Answer 7

Purpose: ensures KVP is accurate (W/in 5% of KVP) And is reproducible (w/ a variation no more than 0.02)
Frequency: annually, MEE, after service/ part replacement

Question 8

Collimation

Answer 8

Purpose: ensures xray field is w/in light field, doesn’t go beyond any edge & chest wall edge of paddle aligns w/ chest wall edge of IR.
Frequency: Annually (3D units)
MEE, after service, new equip (2D)

Question 9

Phantom image eval

Answer 9

Purpose: eval extent in which prior exposures can affect later exposures (lag=shadows)
Frequency: MEE, after service, new equip

Question 10

MEE

Answer 10

Purpose: ensure mammo equip meets section 900.12 b of FDA’s final rule for mammo
Frequency: MEE, service, after replacement

Question 11

MTF

Answer 11

Purpose: more detailed eval to monitor contrast, contrast at low frequencies (1-2 lp/mm) detects masses/fibers. Contrast at high frequencies (4-5 lp/mm) detects microcalcifications
Frequency: Annually, MEE, after service|

Question 12

SNR/CNR

Answer 12

Purpose: SNR how much signal reaches detector vs. noise. High SNR high image quality.
CNR contrast reaching detector vs. noise. High contrast low noise.
Frequency: Annually, MEE, after service

Question 13

Compression paddle deflection

Answer 13

Purpose: ensures adequate compression is applied uniformly over the breast for paddles that are flat/parallel to breast. Paddles not flat/parallel to breast must be evald using manufacturer’s specifications.
Frequency: MEE new units, after service.

Question 14

Room illuminance (rws)

Answer 14

Purpose:eval reading room w/ appropriate ambient lighting. Contrast degraded by extraneous light
Frequency: annually, MEE of new equip, after service

Question 15

Application of compression

Answer 15

Purpose: each system will provide an initial power driven compression activated by hands free controls (automatic) , and fine adjustment compression operable from both sides of pt (manual)
Frequency: MEE of new units, after service

Question 16

AWS QC

Answer 16

Ensure AW monitors clean, free from dust etc. calibrated correctly. Run tests: Monitor condition, test pattern quality, luminance check, luminance uniformity, DICOM grayscale function, monitor manufacturer automated tests

Question 17

Interpretation RWS QC

Answer 17

Physicists test: ambient light, monitor condition, ACR DM phantom, distance measurement, test pattern quality, luminance check, luminance uniformity, DICOM grayscale display function, monitor manufacturer automated test