Radiologic Technology Sequence of Radiography And Basic Cervical Radiography

1. Pharos universityfaculty of Allied medical sciencesClinical Practice I (RSCP-201) Department of Radiological Sciences and Medical Imaging Technology Prof. Dr. Hesham BadawyDr.Mohamed El Safwany  Radiologic Technology Sequence of Radiography And Basic Cervical Radiography

2. Intended Learning Outcomes • The student should be able at the end of this lecture to be able to recognize sequence of steps for adequate radiographic positioning and technicues.

3. Basic Radiographic Room • Tube stand allows vertical and horizontal movement of tube. • Tube can be angled • Collimator restricts beam • Wall Bucky holds cassette.

4. Complete X-ray Room • The Non-Bucky Film holder allows non-grid films that reduce exposure. • The radiographic table makes imaging unstable or handicapped patients safer.

5. Modern control panel • Located behind shielded barrier. • Controls for kVp and mAs. • Selection of focal spot. • Exposure buttons located so operator must be behind barrier.

6. Cassettes • Black border Regular Cassettes are 400 speed and used for spine and general radiography. • Grey Border Cassettesor Extremity Cassettes are 800 speed and used for non-Bucky small extremity films.

7. Filtration System • Additional aluminum filters are added to compensate for varying body thickness. • The filters will reduce exposure in the area that they are placed. • The objective is to equalize the exposure on the film. • The thoracic region is where most filtration is required.

8. Compensating Filters • This rack contains compensating filters and shields. • Top row holds numbered point filters • Bottom row holds cervical thoracic filters and shields. • Shields contain lead that will block the x-ray at the tube.

9. Tube controls • Buttons to release the horizontal and vertical locks to move tube stand. • Button to turn on collimator light. • Tube angle indicator • Knobs to collimate beam.

10. Basic Patient Positions: A-P • Anterior-Posterior • Facing toward Tube • Back touching Bucky • Marker “R” or “L” facing forward. • One of the required views

11. Basic Positions: P-A • Posterior-Anterior • Facing the Bucky • Back toward tube. • Markers “R” or “L” Pronated or facing toward film. • Either A-P or P-A is a required view.

12. Basic Positions: Posterior Oblique • Facing toward tube • Patient turned 40 to 45 degrees from A-P. • Markers:“R”or “RPO” or “L” or “LPO” to indicate the side closest to the Bucky.

13. Basic Positions: Anterior Oblique • Facing toward Bucky • Back toward Tube • Patient turned 40 to 45 degrees from P-A. • Marker: “R”or ”RAO” or “L” or “LAO” pronated indicating the side closest to Bucky

14. Basic Positions: Lateral • Mid coronal plane is perpendicular to film. • Make sure feet are parallel. • Markers used to indicate the side closest to the film.

15. Basic Positions: Recumbent • Can be any of the basic view such as: • A-P • P-A • Oblique • Lateral • All marker rule apply

16. Basic Positions: Decubitus • Taken to see air or fluid levels. • Patient must stay on side for 5 to 10 minutes. • Markers: “R” or “L” to indicate side down. • Arrow to indicate side up.

17. Anatomical Markers • 1. Identify the side of patient closest to film. Lateral & Oblique Views. • 2. Faces the same way as patient. Easy to read for A-P views. Pronated for P-A views. • 3. Identify the right or left side of patient on A-P or P-A views.

18. Tube Angle: Caudal • Tube angled toward the feet. • Decrease SID by one inch for every five degrees of tube angles greater than 20 degrees. • Directs Beam through angled body part.

19. Tube Angle: Cephalad • Tube angled toward head. • For angled greater than 20 degrees reduce SID one inch for every five degrees. • Used to get angled body parts perpendicular to film.

20. Tube Angulation • Erect Radiography requires adding or subtracting the required angle from 90 degrees. • Cephalad angles: Add required angle to 90 degrees. • Caudal angles: Subtract required angle from 90 degrees.

21. Elements of Technique Chart • mAs: Product of mA and time. Determines the number or quantity of photons. Establishes the density of the film. • kVp: Quality of beam. Controls the contrast of the image. • Patient size in centimeters: Determines the mAs and added filters used to equalize exposure. • Focal spot size: Controls geometric resolution

22. Fixed kVp Technique Charts • Consistent image contrast • Proper penetration of body part. • More image latitude: less retakes. • Use of higher kVp will reduce the ionization in body tissue. Reduction in patient exposure.

23. Complete Technique Charts • Chart should be located in the control booth and easy to read. • This will help avoid technique errors. • They will work fine for 85% of the patients.

24. Technique Adjustment for Contrast • Rule of “Tens or 15%” • Increase kVp by 10 or 15% and reduce mAs 50% • Decrease kVp by 10 or 15% and double mAs • Change kVp by 8% and adjust mAs by 25% • If the film is underexposed increase the kVp 15% and leave the mAs alone if patient is unstable. • If the film is overexposed, reduce kVp 15% if it lacks contrast and patient is stable.

25. Technique Adjustment for Contrast • The 15% rule can be used to adjust the technical factors for different patient body habitus or disease processes. • Elderly patients often have osteoporosis and muscle loss making them easier to penetrate. This calls for a reduction in kVp to avoid over penetration.

26. Technique Adjustment for Contrast • Extremely muscular patient need an increase in kVp to avoid under penetration and a light film. • Osteopenic patient require a reduction in kVp by 4 to 10 kVp. • Frail and osteopenic patient require a reduction in both mAs and kVp. • Children require a 30% reduction in mAs.

27. Technique Adjustment for Density • The 30 – 50 Rule is most commonly used to adjust the technical factors for over or under exposure. • If the film is very light or underexposed, double the mAs if the patient is stable. • If it is dark or overexposed, cut the mAs in half. • If it is slightly under or over exposed adjust the mAs 30%.

28. Collimation • A key factor in patient exposure. • Reduces radiation to the area of interest. • Reduces scatter radiation that improves contrast.

29. Collimation Rules • Collimation must be at a minimum slightly less than film size. Or • To the area of clinical interest. Whichever is smaller. • Need three borders.

30. Dark room • Painted a light color. • Should have good safe light. • Sink with eye wash. • Space to store fresh processing chemicals. • Work counter with I.D. Camera.

31. Darkroom: Film Bin • Light tight container for storage of unexposed film. • Small film in front.. • Larger film in back. • Never opened in light or with darkroom door open.

32. Darkroom: I.D. Camera • Used to print patient information from flash card on film. • Card goes under clip to hold it in place. • Film goes next to clip to align information in I.D. Block of film.

33. Darkroom: Film Processor • Kodak M-35 processor • Fresh Chemical storage • Hazardous Waste storage • Film fed into processor on feed tray.

34. Darkroom: Film Processor • Developer is not considered hazardous waste. • Fresh Fixer is not considered hazardous waste. • Used fixer is hazardous waste due to silver.

35. Darkroom: Film Processor • Chemicals in secondary containment. • Air tight containers to keep fresh and reduce fumes. • Always wear eye protection and gloves when handling chemicals.

36. Darkroom: Film Processor • With automatic processing you should not need to become in contact with the processing chemicals. • Only when a film is lost or jammed in the processor will we open the processor.

37. Processing Chemicals • Chemical Safety • Developer contains Hydroquinone and Sodium Bisulfate. Both are hazardous. • Hydroquinone can be absorbed through the skin. • Gloves must be used when in contact with developer.

38. Processing Chemicals • Chemical Safety • Fixer contains Ammonium Thiosulfate and Sodium Thiosulfate. • Since it removes the unexposed silver from the film, it becomes hazardous waste when used. • Fresh Fixer is not hazardous waste.

39. Processing Chemicals • Chemical Safety • Eye Protection and gloves must be used when working on the processor. • Eye Wash facilities should be provided in case of accidental exposure to the chemicals.

40. Sequence of Steps for Taking Radiographs • Introduce yourself to patient. Explain what your are going to do. • Determine that a female patient of child bearing age is not pregnant. Have the patient the sign the release from liability. Give the gowning instructions consistent for the views being taken.

41. Gowning Instructions • Cervical Region : • Remove everything from the waist up and put gown on with opening to the back. • Remove any necklaces, ear rings or dentures and any other items that contain metal in the skull or neck area. • Watch & rings may be left on.

42. Gowning Instructions • Thorax & Chest • Remove everything from the waist up and shoes. • Remove bra. • Put gown on with the opening towards the back.

43. Gowning Instructions Lumbar spine or Full spine • Remove all clothing except for underpants. • Remove shoes but leave socks on • Remove any removable jewelry. • Put gown on with the opening towards the back.

44. Asking about Pregnancy • “It has been reported that the safest time to take x-rays of females of childbearing age is within ten to fourteen days of the onset of menses. Are we within that time frame? If not is there any change that you could be pregnant? Please sign this form that states that to the best of your knowledge, you are not pregnant and the start of the last menses.”

45. Sequence of Steps for Taking Radiographs • Take all measurements needed for the study being taken. Record measurements on the request form. • Locate the radiation protection being used for the first film. • Using the technique chart, determine and set the technique for the first film.

46. Sequence of Steps for Taking Radiographs • Position tube, film and patient. • Set the SID and tube angle for first film. • Place film in Bucky or Non-Bucky film holder. Set I.D. Blocker and anatomical marker in the correct location for the view. Position patient in correct position for the view.

47. Anatomical Markers • Identify the side of patient closest to film. Lateral & Oblique Views. • Faces the same way as patient. Easy to read for A-P views. Pronated for P-A views. • Identify the right or left side of patient on A-P or P-A views.

48. Sequence of Steps for Taking Radiographs • Center horizontal central ray to patient and film to the central ray. Or Set film to patient and center central ray to film. • Push film into Bucky. • Fine tune positioning of vertical central ray. Check all planes and object to film distance.

49. Sequence of Steps for Taking Radiographs • Collimation to area of clinical interest or slightly less than film size. Which ever is smaller. • Step into the control booth. Ask patient to remain still and give the breathing instructions required for the view. • Watch the patient while preparing the rotor and make the exposure.

50. Breathing Instructions • Suspended respiration:” Don’t breathe move or swallow.” Cervical spine A-P and Obliques • Inspiration:”Hold very still. Take a very deep breath and hold your breath in.” Thoracic spine, upper ribs & chest views • Expiration:” Hold very still. Take a small breath in and blow it all the way out and hold it out. Lateral c-spine and all views below diaphragms.