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03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
03 xray film etc
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03 xray film etc

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  • 1. X-ray Equipment The X-ray machine Grids Film and cassettes Processing
  • 2. X-ray FilmTypes of filmHandling of filmChoosing film Depends on size, subject, machine
  • 3. X-ray FilmPurpose: provides permanent record of x-ray image Fluoroscopy/ultrasound traditionally transient Newer technology allows video capture
  • 4. X-ray FilmComposed of silver halide crystals onplastic sheetCrystals interact with: Ionizing radiation (including x-rays) Visible light Pressure Bending Moisture
  • 5. X-ray FilmComposition Similar to photographic film Silver halide emulsion on both sides of polyester base Most film bases are blue tinted Pleasing to the eye
  • 6. X-ray FilmLatent image Formed by absorption of light photon by silver halide crystal Energy of photon dislodges an electron The electron causes positively charges silver ions to join into a silver atom
  • 7. X-ray FilmLatent image formation Br > Br+ e- e- attracts Ag + Ag+ Ag+ > Ag atoms
  • 8. X-ray Film CharacteristicsFilm density Measure of film blackening Equals log of incident light intensity divided by transmitted light intensity
  • 9. X-ray Film CharacteristicsFilm contrast Difference between two densities on a radiograph
  • 10. X-ray Film CharacteristicsFilm contrast Dependant upon: Characteristic curve of the film  Film gamma refers to steepest part of curve
  • 11. X-ray Film CharacteristicsFilm gamma refersto steepest part ofcurve
  • 12. X-ray Film CharacteristicsFilm contrast Dependant upon: Film density
  • 13. X-ray Film CharacteristicsFilm contrast Dependant upon: X-ray exposure  Higher kVp = greater gamma = lower contrast (more visible shades of gray, smaller steps between grays)
  • 14. X-ray Film Characteristics High kVpHigher kVp =greater gamma =low contrast(more visibleshades of gray,smaller steps)
  • 15. X-ray Film CharacteristicsFilm contrast Dependant upon: Film processing  Longer developing times = lower gamma = less contrast
  • 16. X-ray Film CharacteristicsFilm latitude Exposure range that produces acceptable densities (0.25-2.0)
  • 17. X-ray Film CharacteristicsFilm speed Fast films Larger crystals Require less exposure Produces a grainier image Less latitude
  • 18. X-ray Film CharacteristicsFilm speed Slow films Smaller crystals Require greater exposure Higher definition image/less grainy Greater latitude
  • 19. X-ray Film CharacteristicsFilm speed Based upon size of silver halide crystals
  • 20. X-ray Film TypesTwo general types Non-screen film Screen film
  • 21. X-ray Film TypesNon-screen film More sensitive to ionizing radiation Allows for finer detail Requires more exposure Requires thicker emulsion and thus manual processing  Ex.: dental films
  • 22. X-ray Film TypesScreen film Crystals also sensitive to fluorescent light from intensifying screens Less sensitive to direct ionizing radiation Benefits Less exposure Drawbacks Loss of image definition
  • 23. X-ray Film TypesScreen film Blue sensitive film Film responds to ultra-violet, violet and blue light emitted from screen Green sensitive film Respond to screens that emit 60% green and 25% blues Relatively newer technology using rare earth phosphors
  • 24. X-ray Film Types Blue and green screen can be used with either blue or green sensitive film But most efficient if film is sensitive to light emitted by screen
  • 25. X-ray Film TypesScreen film Standard silver halide crystals absorb violet to blue light “Ortho” film Thin layer of green absorbing dye transfers energy to silver halide crystals Therefore extends sensitivity of film into green wavelengths “Pan” film Red absorbing dye
  • 26. X-ray Film TypesScreen film Crossover or punch- through effect Decreased detail of radiograph due to additional exposure to light from screen on opposite side
  • 27. X-ray FilmCommon sizes 14 x14 14 x17 7 x17 8 x 10 10 x 12 11 x 14
  • 28. Intensifying screensThin cleanable sheet of phosphor crystalswhich lies adjacent to the film within thecassettePurpose: To decrease amount of radiation required for a diagnostic radiograph Able to use lower mAs (faster exposure)
  • 29. Intensifying screens4 layers of a screen Base Substrate for phosphor crystals Reflecting layer To reflect light back toward film Phosphor layer Must be uniform and flexible (to avoid cracking) Protective coating
  • 30. Intensifying screens
  • 31. Intensifying screens Intensification factor Direct film requires roughly 34 times more exposure than screen film A 0.1 second exposure on screen film would require 3.4 seconds on non-screen film
  • 32. Intensifying screens Screen speed Larger crystal = faster screen = more grainy Thicker phosphor layer = faster screen = decreased detail
  • 33. Intensifying screens Phosphor layer Calcium tungstate and barium lead sulfate emit blue light Rare earth screens more green light emitted Extremely important to keep screens clean and undamaged
  • 34. Film holdersCassettes Must be rigid, durable, light-proof and transparent to x-rays on at least one face Provide housing for intensifying screens and film Must be maintained well
  • 35. Cassettes
  • 36. Film holdersCardboard or light-proof paper Use for non screen films Light-weight Low/no maintenance
  • 37. Manual Film ProcessingDark room Must be light-proof Tight seal of door Stray light may fog film Must be not be exposed to radiation Adjacent x-ray machine may cause fogging of film
  • 38. Manual Film Processing Dry area Film storage  Use lightproof cabinet Cassette loading Safelight  Must be of visible spectrum that will not fog film  Red part of spectrum
  • 39. Manual Film Processing Wet area Solution tanks Sink Viewer Hangers
  • 40. Manual Film Processing
  • 41. Manual Film ProcessingDeveloping Developer solution reduces silver bromide crystals to black metallic silver
  • 42. Manual Film ProcessingDeveloping Chemical process dependant upon time and temperature Ideally 5 minutes in developer tank at 68 degrees Fahrenheit High temperature causes reticulation  Artifact caused by slipping of emulsion layer
  • 43. Manual Film ProcessingRinse bath Water About 30 seconds
  • 44. Manual Film ProcessingFixer Converts undeveloped silver bromide crystals into a solution that is washed away Black metallic silver left on film Also hardens film
  • 45. Manual Film ProcessingMinimum fixing time Determined by change in film appearance from cloudy to clear (clearing time)
  • 46. Manual Film ProcessingAfter clearing, film should be left in fortwice that amount of time Ex. 2 minutes to clear = keep film in 4 additional minutes Clearing time should not exceed 2-3 minutes
  • 47. Manual Film ProcessingWashing Removes residual silver and fixer 20 minutes if water changes 10 times per hour
  • 48. Manual Film ProcessingDrying Perform in clean cabinet Avoid dust artifacts, water spots
  • 49. Automatic Film ProcessingBenefits Compact size Faster More consistent Time and temperature controlled Produces dry radiograph immediately
  • 50. Film ProcessingSolutions need to be specially disposeddue to contents Treated as hazardous waste in many including California

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