Radiology 15 - Quality Assurance 2

Question 1

What are two other terms for receptor?

Answer 1

plate, sensor.

Question 2

What are 5 reasons an image could be pale?

Answer 2

• Wrong exposure factors (underexposed).

If film:
- Did you leave film in developer tank for long enough?
- Is developer exhausted?
- Is developer at right temperature?
- Is the developer diluted correctly?

Question 3

What happens if phosphor crystals are underexposed?

Answer 3

Phosphor crystals cannot emit light as no interaction with radiation has occurred, meaning there is no information for computer software to convert to a shade of grey hence WHITE SPECKLED AREAS APPEAR.

Question 4

How can you prevent pale image?

Answer 4

FOLLOW QA PROGRAM.

• Select correct exposure factors
• check x-ray tube output

If using film:
- Sensitometry testing of your film
- routine processor maintenance
- top up developer when required

Question 5

What are the causes of a fogged film (aka black strip across film)?

Answer 5

• light leakage in darkroom (from being stored improperly)
• incorrect handling of film (ex. light leakage in glovebox).
• movement artefact (patient moved)

Question 6

How can fogged film be avoided?

Answer 6

• Do coin test in both safelight and glovebox
• correctly store open boxes of film
• TRAIN THE STAFF.

Question 7

What are 5 reasons an image could be dark?

Answer 7

• Wrong exposure factors (overexposed).

If film:
- Did you leave film in developer tank for too long?
- Is developer at a too high temperature?
- Is the developer too concentrated?

Question 8

How can you prevent dark image?

Answer 8

FOLLOW QA PROGRAM.

• routine processor maintenance.
• check developer temperature regularly.

Question 9

What causes a yellow/ greenish film?

Answer 9

Caused by insufficient fixing
consider TIME, TEMPERATURE, DILUTION.

Question 10

How can you prevent yellow image?

Answer 10

FOLLOW QA PROGRAM.

• routine processor maintenance.
• top up fixer when needed.

Question 11

What causes patterned splash marks on film?

Answer 11

Chemicals not being properly washed away during processing.

Dark spots: caused by developer splashes.
Clear spots: caused by fixer splashes.

Question 12

How can you prevent “splashed” image?

Answer 12

• routine processor maintenance.
• regular changing of water in wash tank.

Question 13

What causes a “tree” or “lightning bolt” appearance on film?

Answer 13

Caused by static electricity discharge as a result of film being pulled out too quick from the packet in a dry atmosphere.

Question 14

How can you prevent “tree” or “lightning bolt” appearance on film?

Answer 14

• Proper ventilation in dark room.
• suitable film storage and correct handling.

Question 15

What are two examples of faults to digital systems?

Answer 15

• CURVED MARKS on solid state sensors (damaged pixels on sensor which result in an artefact)
• Phosphor plate image WHITE LINE ARTEFACT (spec of dust on laser in processor which has blocked transfer of data from from one line of pixels).

Question 16

How can digital sensor faults be prevented?

Answer 16

• careful handling, care and storage of digital equipment.
• scanners or processing towers should be regularly maintained by service engineers.
• phosphor plates and sensors should be scanned monthly and checked for damage (also check them visually).

RESULTS SHOULD ALWAYS BE RECORDED IN QA PROGRAMME.

Question 17

What is something that can damage phosphor plates?

Answer 17

Extreme temperatures can damage phosphor layer

Question 18

How often should you check phosphor plates? What damage may you see?

Answer 18

image plates MONTHLY for wear and tear. May see bends, finger prints, scratches or tooth marks.

Question 19

Which regulation are you failing to comply with if you do not replace scratched plates?

Answer 19

IR (ME) R 2017