1. Dr. Mustafa Zuhair Mahmoud Mr. Ali Alhailiy Image Critique نقد صورة الاشعّه 1

2. 1. Film Construction: X-ray film is constructed of four layers basically which are: 1.Base. 2.Adhesive layer. 3.Emulsion. 4.Overcoat (protective) layer. 2 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

3. X-ray Film 1. Film Construction: X-ray film is constructed of four layers basically which are: 3 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

4. X-ray Film 1. Film Construction: X-ray film is constructed of four layers basically which are: 1.Base: 150 to 300 m thick. Lucent. Made of polyester. Blue in color result in less eye strain and fatigue. 4 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

5. X-ray Film 1. Film Construction: X-ray film is constructed of four layers basically which are: 2.Emulsion: This is the active layer. Homogeneous mixture of gelatin and silver halide crystals. The gelatin acts as a suspension agent and prevents the crystals from adhering to one another. And allow the light to pass throw when viewing the image. Two emulsion layers on each side of the film base (1/2000 in thickness). 5 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

6. X-ray Film 1. Film Construction: X-ray film is constructed of four layers basically which are: 3.Adhesive layer: Very thin layer of solution of cellulose ester and gelatin in water and acetone, put on the base. Function of adhesive (substratum) layer to adhere the layers of emulsion to the base. 6 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

7. X-ray Film 1. Film Construction: X-ray film is constructed of four layers basically which are: 4.Overcoat (protective) layer: The purpose of the overcoat of an x-ray film is to protect the emulsion layer. 7 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

8. X-ray Film 2. Film Types (Clinical Usage): A. Direct Exposure Film: 8 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

9. X-ray Film 2. Film Types (Clinical Usage): A. Direct Exposure Film: Used without intensifying screens. Used mainly for extremities, previously for mammography. 9 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

10. X-ray Film 2. Film Types (Clinical Usage): A. Direct Exposure Film: Requires 10 – 100 times more the exposure dose. The emulsion is thicker than screen film. Renders excellent detail. 10 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

11. X-ray Film 2. Film Types (Clinical Usage): B. Mammographic Film: 11 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

12. X-ray Film 2. Film Types (Clinical Usage): B. Mammographic Film: Single emulsion. Fine grain (crystal shape). 12 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

13. X-ray Film 2. Film Types (Clinical Usage): C. Video Film: 13 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

14. X-ray Film 2. Film Types (Clinical Usage): C. Video Film: Exposes images displayed on a video monitor. 14 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

15. X-ray Film 2. Film Type (Clinical Usage): D. Laser Film: 15 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

16. X-ray Film 2. Film Type (Clinical Usage): D. Laser Film: Uses a laser printer. Provides excellent image quality. 16 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

17. X-ray Film 2. Film Type (Clinical Usage): D. Laser Film: Sensitive to red light. Must be processed in complete darkness. 17 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

18. X-ray Film 2. Film Type (Clinical Usage): E. Duplication film: 18 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

19. X-ray Film 2. Film Type (Clinical Usage): E. Duplication film: Single emulsion film. Used for producing copies of radiographs. 19 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

20. X-ray Film 2. Film Type (Clinical Usage): F. Subtraction Film: 20 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

21. X-ray Film 2. Film Type (Clinical Usage): F. Subtraction Film: A type of single emulsion film used with angiography. 21 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

22. X-ray Film 2. Film Type (Clinical Usage): F. Subtraction Film: One type prepares a positive copy of the image. The other type enhances subject contrast and detail. 22 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

23. X-ray Film 2. Film Type (Clinical Usage): G. Cine Film: 23 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

24. X-ray Film 2. Film Type (Clinical Usage): G. Cine Film: Used with cardiac catheterization. 24 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

25. X-ray Film 2. Film Type (Clinical Usage): G. Cine Film: Produced in 16 and 35mm sizes. Also used for radiography of the esophagus. 25 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

26. X-ray Film 2. Film Type (Clinical Usage): H. Spot Film: 26 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

27. X-ray Film 2. Film Type (Clinical Usage): H. Spot Film Produced in 70 and 105mm sizes. Used in fluoroscopy with a spot film camera. 27 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

28. X-ray Film 2. Film Type (Clinical Usage): I. Dental Film Periapical Dental Film Bite-wing Dental Film 28 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

29. X-ray Film 2. Film Type (Clinical Usage): I. Dental Film Occlusal Dental Film Orthopantomographic (OPG) Dental Film 29 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

30. X-ray Film 2. Film Type (Clinical Usage): I. Dental Film Exposed either intraorally or extraorally. Intraoral films are small, double-emulsion films. Extraoral films are large, single-emulsion films. 30 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

31. X-ray Film 3. Film Type (Exposure): A. Screen Film: Films exposed to combination of X-ray and light (screen film). 31 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

32. X-ray Film 3. Film Type (Exposure): B. Non Screen Film: Films exposed to x-ray only (non screen film). 32 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

33. X-ray Film 3. Film Type (Exposure): C. Fluoroscopy and Copying Films: These Films are exposed to light only. Coated by the emulsion in one side and called single sided films. 33 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

34. X-ray Film 5. Film Handling and Storage: Each of the following can have a negative effect upon film contrast. 1. Improper handling. Causes artifacts. 34 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

35. X-ray Film 5. Film Handling and Storage: Each of the following can have a negative effect upon film contrast. 2. Heat and humidity. Too much humidity can cause the emulsion to swell. 35 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

36. X-ray Film 5. Film Handling and Storage: Each of the following can have a negative effect upon film contrast. 2. Heat and humidity. Too little humidity can cause static to develop the film. 36 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

37. X-ray Film 5. Film Handling and Storage: Each of the following can have a negative effect upon film contrast. 2. Heat and humidity. Too much heat can fog film. 37 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

38. X-ray Film 5. Film Handling and Storage: Each of the following can have a negative effect upon film contrast. 3. Light and radiation. Exposure to each can fog film decreasing contrast. 38 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

39. X-ray Film 5. Film Handling and Storage: Each of the following can have a negative effect upon film contrast. 4. Shelf life. Film loses speed, contrast and begins to fog with age. 39 Assistant Prof. Dr. Mustafa Zuhair Mahmoud

40. CR Cassettes Comprises of: 1. A protective outer cassette case 2. A PSP plate 3. A chip for temporary storage of patient information

41. Photo-Stimulable Phosphor (PSP) A phosphor is a substance that exhibits the phenomenon of phosphorescence (sustained glowing after exposure to light or energised particles such as electrons). The most common types of phosphor in these plates are BaF:Eu++. (Barium Fluoro Europium)

42. CR Plate Structure

43. Protective Coat Electron beam cured to reduce the amount of laser beam reflection that occurs during secondary excitation.

44. Phosphor Layer The thickness of this layer has a direct impact on image quality. PSP is made either of BaF:Eu++ or BaFI:Eu++

45. Anti-Halo Layer This layer is to prevent back-reflection of the of the laser light into the phosphor. It is normally a blueish colour. Can you think why? Absorption, because the laser is normally red.

46. Support Layer This polyurethane (PET) layer gives strength and support to the plate.

47. Laminate This layer provides further support.

48. CR Cassettes Hard outer cassettes provide durability and functionality. These are commonly made either of plastic or carbon fibre,both of which have good radio- lucency in proportion to theirsupport qualities and durability.

49. Communication Patient ID is normally inputted on a PC workstation and transferred or wrote to an embedded chip within the cassette by magnetics or radio-waves This information is then read by the reader during the reading process.

50. Communication Barcode scanners are commonly used to automatically identify cassettes. This speeds up the administration process.

51. Readers

52. The Reading Process 1. Primary excitation 2. Secondary excitation 3. Photomultiplication 4. Digitisation 5. Plate erasing

53. Excitation Excitation is the elevation of the energy levels of a substance from its normal or ground state There are two levels of excitation in CR plates: – Primary – Secondary

54. Primary Excitation The x-rays pass through the upper layer to the phosphor. The x-rays react with these molecules, causing inner shell electrons to become outer shell electrons. Most of these drop back to their initial state (70%) The rest (30%) get trapped in electron traps These traps are caused by the addition of impurities into the Barium Fluoro Halide (i.e., Europium) This is effectively stores the image within the plate (the latent image)

55. Secondary Excitation The plate is removed from the cassette and passes by a laser beam. This beam reacts with the trapped electrons

56. Secondary Excitation The laser stimulates the phosphor plate enough to release the trapped electrons to their orignal state. This causes light to be emitted. The light produced is channeled to a photomultiplier using optics (lenses and mirrors) The number of light photons produced by secondary excitation is directly proportional to the number of electrons that were trapped in the storage phosphor.

57. A red laser is used for secondary excitation, but green light is emitted. There is then a filter for omitting non-green light (i.e., specular reflections from the primary laser)

58. The Photomultiplier Extremely sensitive detectors. These amplify or multiply light signals into signals up to 100,000,000 times

59. Digitisation A/D Convertor PMT

60. Plate Erasing. A white light source, typically a fluorescent lamp with an attached colour filter, quickly erases the image plate. Now the plate can be reused.

61. 61