Processor Quality Control Problem Solving

1. Processor Quality Control Problem Solving Midterm Topic 2

2. Processor Quality Control • Process of Processor Quality Control • Check the temperature of the developer by use of a thermometer. • Check water temperature. • Check fixer temperature. • If developer temperature is within ± 0.5° of specifications produce and process the sensitometric strip.

3. Check Developer Temperature • Proper development of the latent image is dependent upon: • Developer temperature • Concentration of developer solution • Time film spends in the developer • Temperature must be to specifications

4. Check of Water Temperature • If the water is too cold, it will be more costly to heat the developer to operating temperature. If water is too warm, the developer will over heat.

5. Check of Fixer Temperature • The fixing of the image is dependent upon the fixer being within factory specification but is not as critical as developer temperature.

6. Expose Sensitometric Strip • The Sensitometer produces highly reproducible step wedge images used to monitor the performance of the developer. • Using film set aside for processor quality control, expose both sides of the film with the Sensitometer.

7. Process the Sensitometric Strip • Always feed the film into the processor the same way and on the same side of the feed tray. • Bromide drag and affect the image.

8. Read the Sensitometric Strip • A Densitometer is used to read the optical density of the strip. • Read an area of unexposed film to check the base plus fog (B+F) of the image. • Then read the Speed and Contrast Steps.

9. Read the Sensitometric Strip • The amount of light passing through the image is the optical density of the image. • Speed or Mid Density is the step closest a reading of 1.00 + Base+ Fog or 1.20 OD • Contrast or Density Deference is the deference between the steps closest to 0.25 + Base + Fog or 0.45 and the step closest to 2.00 + Base + Fog or 2.20 OD.

10. Graph the Results on the Processor QC Chart • The processor should be checked before x-rays are taken on the first patient. • If a problem exists, it must be corrected before processing patient films.

11. 21.3 Processor QC Problem Solving • Processor QC monitors the development of the film. These factors impact development: • Developer Temperature • Time of Development • Activity of the Developer • Also the darkroom and film storage conditions will impact Processor QC.

12. Base Plus Fog • Any unexposed area of the film can be tested to determine the Base Plus Fog exposure level. • Base Plus Fog is the level of pre-existing exposure exposure above the blue tint of the base of the film.

13. Base Plus Fog • Items that will impact the Base Plus Fog includes: • Condition of film storage after manufacture. • Light integrity of the dark room • The light spectrum from the safelight • Temperature of the developer • Contamination of the developer

14. Speed Index or Mid Density • This is the step closest to 1.00 plus B+F or 1.20 Optical Density. It corresponds to the middle of the useful exposure level on x-ray film. • Factors that will impact the Speed Index include: • Developer Temperature: Low Temperature will produce lower speed.

15. Speed Index or Mid Density • Developer Temperature: High Temperature will produce increased speed. • Fog level of the film: Increased Base + Fog will increase the Speed Index. • Time spent in the developer: Increased time at the correct temperature will increase speed. • Activity of the developer: under replenishment will lower the Speed Index

16. Speed Index or Mid Density • Activity of the developer: under replenishment will lower the Speed Index • Over replenishment will result in increased Speed Index. • Contaminated Developer: If fixer gets into the developer, the developer will be contaminated.

17. Contrast or Density Difference • Contrast Index is the difference between a step that produces a light shade of gray (0.25 O.D. + B+F) and the step that produces upper range of viewable light on an exposed film (2.00 + B+F) • Step closest to 2.20 minus Step closest to 0.45 equals the Contrast Index.

18. Contrast or Density Difference • Factors that will affect the contrast level include: • Fog level on the film • Developer Temperature • Development Time • Contamination of the developer

19. Processor QC limits • The action level or results that should result in corrective steps being taken vary between national limits and those recommended by California. • California recommends the tightest standards that will produce the most consistent image quality.

20. Processor QC limits • Developer Temperature: ± 0.5° F (Ca); ± 1 to 2° F.(US) • B+F: + 0.03 OD (California); + 0.05 OD (US) • Speed Index: ± 0.10 OD (Ca.); ±0.15 OD (US) • Contrast Index: ± 0.10 OD (Ca.); ±0.15 OD (US) • The California Standards are used in this course.

21. Monitoring Frequency • Daily when patients will be x-rayed: • Check fresh chemical levels • Check that water flowing into wash tank and tank is full • Check drive gears for wear. • Check developer temperature when heater begins to cycle. • Clean work surface and feed tray of processor.

22. Monitoring Frequency • Daily when patients will be x-rayed: • Clean cross over rollers or process two to three roller cleaning films. • Perform Processor Sensitometry or QC • Determine B+F, Speed and Contrast Index • Chart results • Analyze results and take action as indicated.

23. Monitoring Frequency • At close of business each day or shut down: • Raise cover of processor about two inches • Drain wash tank • Semi-annual and at startup tests: • Immersion time or Speed of Processor Drive • Water Flow Rate

24. Chart 1 • Problem solving: • Start with developer temperature • Then look at Base + Fog • Then look at Speed Index

25. Processor within Limits Chart 1 • With proper developer temperature, reasonable volume of films processed and proper rate of replenishment the processor should stay within limits. • After cleaning the speed will increase due to fresh developer. This is normal.

26. Processor within Limits Chart 1 • Trends can be monitored when the processor is within limits. • Continued lower than normal speed index is a symptom of under replenishment. A slight increase in replenishment may be warranted

27. Processor within Limits Chart 1 • If you are under replenishing the chemicals and the case volume drops, the developer may go bad. • Continued high reading means over replenishing of the developer.

28. Chart 2 • Problem solving: • Start with developer temperature • Then look at Base + Fog • Then look at Speed Index

29. Problem #1 Chart 2 • Symptoms: • B+F and Speed are up • Contrast is down • Developer Temp normal • Diagnosis: • Problem with dark room with safelight or light leak in darkroom.

30. Problem #1 Chart # 2 • Solutions: • Check bulb wattage in safelight • Check for light leaks • Check for damage to filter in safelight. • Check fluorescent fixture for after glow. • Move safelight

31. Chart 3 • Problem solving: • Start with developer temperature • Then look at Base + Fog • Then look at Speed Index

32. Problem #2 Chart #3 • Symptoms: • Gradual decrease in Speed Index • Temperature within limits • B+F within limits • Diagnosis: • Low volume of films processed • Under replenishment

33. Problem #2 Chart #3 • Solutions: • Run two to three fresh 14”x17” films or roller cleaning films each day through processor. Do Not run rejected films as they will contaminate the developer with residual fixer.

34. Problem #2 Chart #3 • Solutions: • Slightly increase the developer replenishment rate until the volume of cases increase. • Check for low levels of chemical in processor tanks.

35. Chart 4 • Problem solving: • Start with developer temperature • Then look at Base + Fog • Then look at Speed Index

36. Problem #3 Chart 4 • Symptoms: • Gradual rise in speed and contrast • Sudden drop in Speed, Contrast and Developer temperature • These are two separate but common problems.

37. Problem #3 Chart 4 • Symptoms: Gradual rise in speed and contrast. • Problem: If the volume of x-ray films processed each day increases significantly, the developer will be over replenished. • Solution: If film processing volume remains high, reduce replenishment .

38. Problem #3 Chart 4 • This is not typically recommended because a drop in film volume will quickly result in under replenishment. • Other factors that can cause this increase: • a new box of control film that is a little faster. Change aim if speed changes with the new box of control film.

39. Problem #3 Chart 4 • Other factors that can cause this increase: • a drop in the drive speed will cause the film to remain in the developer longer. This can be the result of a bad bearing, or roller or problem with the drive motor. • Always check the developer temperature first.

40. Problem #4 Chart 4 • Problem 2 Symptoms: • Drop in developer temperature, speed and contrast. • Diagnosis: Developer Temperature Control Problem or the test was done before the developer reached operating temperature.

41. Problem #4 Chart 4 • Solutions: • If the developer temperature was checked before the strip was run, the problem would have been addressed without the need for the film. • It is very important to know how long it takes the processor to warm up in the morning. Time varies from 20 to 45 minutes.

42. Problem #4 Chart 4 • If some time has passed between the check of the developer temperature and processing the control strip, the following must be considered: • The developer thermostat, developer heater or fuse for the heater has failed. • Most processor will have a light that blinks when the heater is on. If the light remains out, the heater is not working.

43. Problem #4 Chart 4 • If the water coming into the processor is too cold, the developer heat controls will: • Fail prematurely because of excessive needs for heat. • You will use more power to maintain the developer temperature.

44. Chart 5 • Problem solving: • Start with developer temperature • Then look at Base + Fog • Then look at Speed Index

45. Problem #5 Chart 5 • Problem: Repeated increases in developer temperature, Speed Index and Contrast Index • Solutions: The developer temperature is controlled by the heater, thermostat and water temperature on most processors. The problem will generally be within these systems.

46. Problem #5 Chart 5 • If the water was not turned on, the developer will over heat. • If the water was turned on but the water flow control valve is defective or clogged, the developer will over heat. • Test control valve every six months • Use a water filter to control mineral content of water.

47. Problem #5 Chart 5 • The thermostat may have failed closed resulting in the over temperature condition. • The film may have been run with the processor set at the wrong speed and developer temperature. • Medical facilities use extended processing for mammography to reduce radiation by increasing speed and improve contrast.

48. Problem #5 Chart 5 • IF the Speed Index, Contrast Index and Base + Fog increased with normaldeveloper temperature, the drive system is faulty.

49. Chart 6 • Problem solving: • Start with developer temperature • Then look at Base + Fog • Then look at Speed Index

50. Problem #6 Chart 6 • Symptoms: Speed Index and Contrast Index continue to fail with normal developer temperature and processing speed. The processor is fine right after service. • Solution: The processor is under used due to very low exam volume.