X-RAY FILM PROCESSING [Autosavee/d].pptx

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1. X-RAY FILM PROCESSING Presented by Prativa Khanal Bscmit 1 st year National Medical college and Teaching hospital

2. INTRODUCTION Film processing refers to the chemical treatment of radiographic film to convert the latent image captured on the film into a visible image. Film processing is an essential and is typically performed in a darkroom or by a professional film processing service.

3. PURPOSE OF FILM PROCESSING To develop the invisible aerial image into a visible permanent image by converting exposed silver(Ag) halide crystals from the film emulsion to metallic silver

4. TYPES OF FILM PROCESSING MANUAL FILM PROCESSING AUTOMATIC FILM PROCESSING

5. STEPS IN MANUAL PROCESSING Developing Rinsing Fixing Washing Drying

6. Developing First step of manual processing Invisible image is converted into visible by chemical processing Developer used in this step is reducing agent which donates the electron

7. CONSTITUENTS OF DEVELOPER Solvent: Water, mixing and dilution of chemicals Developing agent : Phenidone Hydroquinone(PQ) and Metol Hydroquinone(MQ)-reduces the exposed Ag halide to black metallic silver Acclerator: Potassium hydroxide(KOH) or potassium carbonate (K2CO3)-makes developer soln alkaline(pH-9.8 to 11.4)

8. Restrainer: Potassium bromide or sodium bromide-keep basic development fog minimum so it is called as anti-fog agent Preservative : Sodium or Potassium Sulphite- prevents rate of aerial oxidation of the developing agent Buffer : Boric acid with sodium hydroxide-maintains the pH of the developer soln.

9. Hardener: Glutaraldehyde-prevents jamming & damage to the film from over swelling of gelatin Sequestering agent: EDTA(Ethylene Diamine Tetra Acidic Acid)-prevent the precipitation of insoluble mineral salts Fungicide and bactericides: Phenol-prevent growth of bacteria & fungi on soln..

10. FACTORS AFFECTING DEVELOPING TIME: standard time is about 4-5min for manual processing. If developing time is long ,film appears dark and vice versa TEMPERATURE : standard tempr 20-25°C AGITATION: reduces the time of development and prevent air ball marks EXHAUSTION OF SOLN : bromine ions goes into developer which decreases the developing action TYPES OF EMUSION : developer soln takes longer time to penetrate a thick emulsion than a thin one

11. RINSING 2 ND step in manual processing Helps to prevent further development after removing the film from developer tank Two methods: Water rinse method Acid stop bath

12. FIXING Third step in manual processing Removes the unexposed silver halide without damaging the image Purpose of fixing is: To prevent further development To clear the image To fix the image

13. CONSTITUENTS OF FIXER Solvent: water-dissolves the constituents. Fixing agent: Sodium or Ammonium Thiosulphate-react with unexposed Ag halides to produce water soluble silver complex which are deposited in fixing solution AgBr+Sodium thiosulphate → AG thiosulphate complex+Ag Acid: Acetic acid- neutralized alkaline developer and make acidic medium(PH-4 to 4.5) Hardener: Aluminium chloride or Al sulphate-reduce swelling of emulsion during processing

14. Buffer :-Sod acetate with acetic acid- to maintain PH of fixer Preservatives: -Sodium sulfite-prevent decomposition of fixing agents & prevent the solution from decompose Anti-sluding agent :-Boric acid-prevent the formation of sludge in fixer solution

15. FACTOR AFFECTING FIXING SOLUTION Type of fixing agent used - Ammonium thiosulphate is more rapid in action than sodium thiosulphate Tempr of solution - Increasing temperature of fixing solution result in shorter clearing time Concentration of fixing agent -higher concentration of fixing agent result in shorter fixing time Thickness of emulsion -thick emulsion takes more time than thin emulsion

16. WASHING Fourth step of manual processing Tap water is used in washing the film If not washed properly ,a yellow brown sulphur stain is seen on film

17. DRYING Final stage Removes all surface water and retained in emulsion Done in dry and dust free cabinet circulated with hot air,away from sunlight. Drying time is 10-15minutes

18. TANKS FOR MANUAL PROCESSING Container used to mixed and storage of chemicals Materials used should be inert,strong and heat resistance Commenly used materials-hard rubber and stainless steel

19. FILM HANGERS Hangers are metal frames in which films are suspended processing Purpose of hangers: Support the film and allow it to be manipulated without handling of the emulsion Permit the number of films to be processed simultaneously and to keep them separate from each other during the procedure

20. STORAGE OF CHEMICALS Chemical store design should have adequate ventilation,satisfactory illumination,dust free environment ,automatic smoke detectors and secure locks

21. ADVANTAGES OF MANUAL PROCESSING It is cheap Has less chance of mechanical breakdown Little variation in exposure may not hamper the image quality Film can be taken out in between the process

22. DISADVANTAGES OF MANUAL PROCESSING It has long processing time It required more space Chemical contamination occurred to the operator More number of manpower required

23. AUTOMATIC PROCESSING It is a self-guided process which is done in automatic processor where all the conditions required are already fixed. It is widely used fast and convenient process.

24. STEPS FOR AUTOMATIC PROCESSING Developing-formation of image Fixing-stopping of development, permanent fixing of image on film Washing-removal of residual fixer Drying-warm air blowing over film

25. WORKING OF AUTOMATIC PROCESSING When an exposed film is kept in input tray of processing Film detected by micro-switch and gently advanced to the developer Film moved towards the fixer by self-guided roller and squeezing rollers Power provided through a D.C motor Then,advanced to washing chamber and drying section

26. SYSTEMS OF AUTOMATIC PROCESSOR Film entry or feed system Transport system Temperature control system Recirculation system Replenishment system Dryer system Electrical system

27. FILM ENTRY OR FEED SYSTEM(feeding tray) An ideal film entry system consists of a pair of rollers and a micro-switch Lower roller is fixed and top roller is heavy and provided with movement

28. TRANSPORT SYSTEM Consists of series of rollers An electric motor drives And the racks

29. TEMPERATURE SYSTEM Maintains developer,fixer and dryer temperature Processing Temperatures Developer 35°C Fixer 35°C Washer 32-35°C Dryer 57°C

30. RECIRCULATION SYSTEM Developer and fixer are constantly passed through the thermostat,temperature gauze,heat exchanger,circulation pump,heater and filter

31. REPLENSHMENT SYSTEM Prevents both the quality and quantity of the chemicals Consists of replenisher tanks,filters and replishment pumps This system helps to develop the alkalinity and strength Helps the fixer solution to maintain its acidity and strength

32. DRYER SYSTEM Dries the film before its removal for viewing Consists of blower, ventilation ducts, vented dryer tubes and exhaust system Tempr of drying air is usually 50°C

33. ELECTRICAL SYSTEM It provide electrical power for the operation of automatic processor

34. PROCESSING RATES DEVELOPER: 20-25 sec FIXER-15 sec WASHING-15 sec DRYER: 24 sec TRAVEL TIME: 10 sec Total time :90 sec

35. CARE AND MAINTENANCE OF AP Automatic processor should be maintained according to rules and regulation provided by company on daily, weekly and monthly routine. Main principles are common to most of the machines

36. STARTAR SOLUTION Startar is basically an acidic restrainer Added to the fresh solution in the development to reduce the initial activity of developer to the safe working level by bringing down the PH to correct value

37. ADVANTAGES OF AUTOMATIC PROCESSING Has short processing time Less manpower required Less space required No chemical contamination for operator Quality and quantity of the solutions are maintained to a high standard

38. DISADVANTAGES OF AUTOMATIC PROCESSOR More expensive Has more chance of mechanical breakdown Strict role and regulation to get quality image Requires diligent maintainance

39. DRY FILM PROCESSING No use of chemicals for processing of films like in wet processing Single emulsion film Procesed by light or heat Two types: Photothermography Thermography

40. PHOTOTHERMOGRAPHY Processed by use of laser light Film used in this processor is light or x-ray sensitive Load and unload of film isnot done in prompt light condition Manufacture companies – Konica,kodak and fuji

41. PROCESSING IN CR SYSTEM INTRODUCTION: Computed Radiography also commonly known as photostimulable phosphor(PSP) imaging PSP plate is used in CR Digitial replacement of conventional x-ray film radiography CR uses a flexible phosphor imaging plate to capture digital images instead of conventional radiographic film

42. HISTORY 1973- George Luckey KODAK patented the first optically scanned storage phosphor system 1983-FUJI was first to commercialized a CR system

43. Layers of imaging plate Protective layer Phosphor layer Reflective layer Conductive layer Support and base layer Backing layer

44. CR CASSETTE Lightly weighted Made of plastic Front side made of low attenuation carbon fiber Back side made of high atomic number to reduce backscatter Cassette holds and protect the imaging plate and provides protection from dust

45. PROCESSING: Process the data digitally to produce high quality radiographic images PRINCIPAL Based upon PSL principal (Photo stimulable luminescence) light Excited Emission of light CR employs a phosphor which works on PSL principal (phosphor-made up of europium activated barium fluoro halide,BaFX:Eu 2+)

46. WORKING When imaging plate is exposed to X-ray photons,energy from incoming radiation is stored in phosphor layer in the form of trapped electron(latent image) A specialized machine CR reader is used to read out the latent image from the plate by stimulating it with very finely focused laser beam Phosphor will emit blue light(luminescence) The light is then dected by a highly sensitive analogdevice known as photo multiplier(PMT) and converted to a digital signal

47. ADVANTAGES Images are stored in digital form Phosphor imaging plate are re-usable thousands of times Image processing time is generally shorter than manual film processing Processing chemicals, dark room & Storage room required Reduction of repeat exposure Image quality is better than conventional screen

48. DISADVANTAGES High equipment cost Higher noise Lower spatial resolution

49. THERMOGRAPHY Processed by use of heat Film used in this processor is heat sensitive but not light sensitive Load and unload of film is possible in light prompt condition Manufacture company- AGFA

50. COMPARISON MANUAL WETTING:15s DEVELOPMENT: 1. 4min 2. no starter solution 3. temp 20°C 4. developer less conc AUTOMATIC WETTING: not needed DEVELOPMENT: 1. 26S 2. starter solution needed 3.temp 35°C 4.developer more conc

51. MANUAL RINSING : done for 30s FIXING:8-10min WASHING:15-30 min DRYING:10-15 min (hanger needed) AUTOMATIC RINSING : not needed FIXING:15 sec WASHING:15 sec DRYING: 25 sec (hanger not needed)

52. MANUAL Long processing time Work load cannot be increased More space required More manpower Poor quality control Chemical contamination AUTOMATIC Short processing time Work load can be increased Less space required Less manpower Improved quality control No contamination

53. MANUAL Darkroom conditions and chemistry required More processing time Film is evaluated by film viewer Cheap More manpower required CR No darkroom and chemistry required Processing time is 1-3min depending on scan resolution Computer with viewing/analysis software Expensive Less manpower required

54. References Radiographic imaging, DN & MO Chesney, CBS Publishers & Distributors, India. Chesneys’ Radiographic Imaging, John Ball & Tony Price, 6th edition, Oxford Blackwell Scientific Publication Varoius internet sites

55. Thank you