Mrt 261

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Mrt 261
2012-04-22 15:08:37

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  1. What technical factors and positioning components should you double check when positioning for a townes view to ensure a good image?
    • Ensure that the top of the IR is not lower than the vertex of the skull.
    • Also the CR and the IR may not be aligned especially when angling 37 degrees.
    • Always double check that they are aligned.
  2. If the IR is not aligned with your tuve for a Townes image, what would the image look like?
    Your image may cut off the vertex of the skull and the image may appear light/noisy because of the AEC
  3. What is a manual exposure technique for a lateral skull with a grid ?
    Average technical 12 mAs @ 80 kV
  4. Could uoui perform all cranial views using either the table bucky or the wall bucky?
    Yes all views can be performed on either the table or wall bucky.
  5. Would it be appropriate to perform sinus images using the table bucky?why or why not
    No, the projections should only be performed upright to demonstrate air fluid levels
  6. How would the exposure technique change from the caldwell skull posotion as compared to the caldwell sinuses position ?why
    • The technique would decrease for sinuses because you do not need to penetrate the bones of the skull to properly demonstrate the sinuses.
    • If you used a skull technique to image the sinuses, the sinuses would be too dark to properly critique.
  7. For the images of the sinuses with the patient upright could you angle the tube instead of changing the patient position?
    Optimally you would only want to adjust the patient's head and keep a horizontal ray to demonstrate fluid levels accurately.
  8. If the patient was a trauma case and could only lie on their back what position could you perform to still be able to visualize air fluid levels in the sinuses
    The lateral cross-table position would be the best view to demonstrate air fluid levels in this scenario. (Patient is supine with horizontal beam).
  9. When imaging facial bones where should the petrous pyramids be demonstrated on the caldwell view
    • The petrous pyramids should be in the lower one third of the orbits(15° angle) or at the infraorbital margin (20° angle)
    • – depending on procedure required at the clinical site
  10. Which bones are of special radigraphic interest for the facial bones series
    Maxilla, zygoma, mandible
  11. Two views are routinely performed for the orbits
    • Modified Waters
    • Modified Caldwell and lateral view
  12. Would you use a special cassette to perform radigraphic imaging of the orbits when querying a foreign object?Why or why not
    You would use a specially cleaned cassette to ensure that there are no artifacts that could be misconstrued in the diagnosis of the image
  13. With reference to the IR, how should the midsagittal plane be adjusted for the tangential view demonstrating an individual zygomatic arch?
    from perpendicular, rotate 15° towards affected side and then tilt chin 15° towards central ray
  14. What equipment options do many facilities have to visualize the mandible
    Panorex Unit
  15. What markers are important to have visualized on the lateral TMJ views
    Markers are essential to indicate the patients mouth be open or closed for each image
  16. What are your options for positioning oblique views of the mandible to accommodate
    If the patient has a short neck or wide shoulders you could angle the patient's head and angle your tube to a total of 25 degrees instead of just angling the tube 25 degrees cephalad and having the patient's head lateral. Example: patient’s head is angled 15° and the tube is angled 10°
  17. What is the central ray for the posterior projection 0 degree Caldwell of the mandible?
    Perpendicular to the acanthion
  18. The midsagittal plane should be rotated-----degrees from the lateral position to demonstrate the body of the mandible for the Axiolateral view.
    30 degrees
  19. what angle is used for the central ray of the aziolateral view of the mandible?
    25 degrees cephald
  20. How is the excursion of a condyle demonstrated on a Schuller's view
    • Open mouth-Out of the mandibular fossa
    • Close mouth-Inside the manidibular
  21. What bony structures make up the TMJ
    • Mandibular fossa of the temperal bone
    • The condyle of the mandible
    • Mandibular condyle
  22. What part of the mandible is well demonstrated on a posteroanterior projection
  23. A Schuller's view for the TM joints requires a tobe angle of
    25-30 degrees caudad
  24. The unaggected TMJ will be demonstrated inderior and anterior to the affected TMJ on the Schuller's view.
    True or false
  25. To demonstrate the symphysis of the mandible on the axiolateral view , the head should be turned---to bring the part parallel to the cassette
  26. What type of fracture displacement is best demonstrated on a posteranterior projection of the mandible
    Lateral and medial displacement
  27. Why should the chin be extended when imaging the mandible in the oblique views?
    • The chin is extended to et the area of interest away from the c- spine
    • ( not superimposed over c-spine)
  28. Where will the petrous pyramids be demonstraed on a PA projection of the mandible?Where would they be demonstrated if the chin was tucked too far down ?
    • The pertrous pyramids should be demonstrated extirly in the orbit.
    • If chin tucked too far down they be projected above the orbits
  29. What are the Schuller's images performed with the mouth closed closed and opened?
    To view the TMJ open and closed for displacement (excursion) of TMJ
  30. What is the central ray for the Townes view of TMJ's?
    35 degrees caudad 3in above the nasion
  31. To obtian 30 frontooccipital projection of the skull with the infraorbitomeatal line perpendicular to the table the central ray is directed
    37 caudad
  32. Which line view of the skull what are tow things your can critique to identify if there is rotaion or not
    • Lateral borders of the skull are superimposed
    • Sella turcica is in profile
    • Maxillary struts aare superimposed
  33. On a lateral view of thekull the patient's midsagittal plane is-----to the IR and the coronal plane is -------to the IR
    • Parallel
    • Perpendicular
  34. In regards to the morphology of the skull which shape presents with the pertous pyramids at an angle of 54 to the mdisagittal plane
  35. Where is the dorsum sella seen on Townes's view of the skull?
    Centered within the foramen magnum
  36. For a 15 degree caldwell view of the cranial bones where would the pertrous pyramids be demonstrated
    Lower 1\3 of orbits
  37. What is the direction of the central ray for the reversed caldwell
    15 cephalic entering the nasion
  38. What projection is the caldwell position
    15 Occipitalfrontal projection
  39. Which projection/view that demonstrates the foramen magnum
  40. The OML is at degrees to the cassette for the Townes projection
    True or false
  41. How many degrees are there between the OML and the IOML
    • OML is 30
    • IOML is 37
    • 7 degree difference
  42. For the lateral view of the cranium the interpupillary line is --- it the IR
  43. What is the landmark line that should be perpendicular to the cassette for the water's view of the sinuses?
    Mentomeatal line
  44. What patient position should a patient be in for imaging the sinuses and why
    • Erect
    • For air and fluid levels
  45. Which projection/view best demonstrates the frontal sinuses
    • Parietoacanthion
    • 15 occipitofrontal procjection Caldwell
  46. What is the central ray for the lateral view of the facial bones
    • Perpendicular to lateral surface of upper zygoma
    • 1\2 way between outer canthus and EAM
  47. For the 15 occipitofrontal projection the petrous pyramids shoudl be demonstrated with in the lower maxillary sinuses
    True or false
  48. The parietaoacanthial projection will best demonstrate the
    maxilla and orbits
  49. The ---(OML/IOML)forms an angle of ---with the bucky for the waters view
    • OML
    • 37 degrees
  50. For the reverse waters ofo the facial bones describe the central ray if the mentomeatal line cannot be extended enough to be perpendicular to the IR
    The central ray becomes parallel to the mentomeatal line
  51. The mentomeatal line is perpendicular to the IR for the Parietoacanthial projection(Transoral) of the sinuse
    True or false
  52. If the skull is under extended during imaging of the sinuses for the Parietoacanthial projection where will the petrous pyramids be projected
    The petrousl pyramids will be projected in the maxillary sinuses
  53. The long narrow head is termed
  54. For the Dolicocephalic the petrous pyramids forms and angle of ---to the ---plane of the skull
    • 40 degrees
    • midsaggital plane
  55. Which image best demonstrates the nasal septum
    • Wates view
    • Parietoacanthion projection
  56. What are the two structures of interest shown on the waters view of the sinuses
    • Maxillary sinuses
    • foramen rotundum
  57. State the central ray for the lateral view of the sinuses
    Perpendicular to 1\2 to 1in poterior from the outer canthus
  58. On a townes view the zygomatic arches are projected laterally to the mandibular rami
    true or false
  59. A displacement fracture of the nasal septum would be best demonstraed on an
    Parietoacanthial projection
  60. What reduction in exposure technique is required for a townes view of the zygomatic arches
    50 percent
  61. Name three ways in which the radigrapher can ensure optimum detail for images of the orbits
    • 1 Small focal spot
    • 2 Close OID
    • 3 Long SID
    • 4 Patient very still
    • 5 Clean IR
    • 6 Good positioning
  62. Which projection \ view will best demonstrate a depressed fracture of the zygomatic arches
    Infersuperior projection(tangential view )
  63. What is the best exposure technique to use for a lateral view of the nasal bone
    A finger technique is best used for the nasal bones
  64. When performing a tangential view of the zygomatic arches state whether the statement is True or false
    -----The midsagittal plane is not perpendicular to the bucky
    -----The coronal plane is parallel to the bucky
    • True
    • False
  65. To determine if a foregn body is either superficail or deeply lodged in an eye the patient should look side to side for the ---view and look up and down for the --view
    • Modified caldwell/waters modified
    • Lateral
  66. Specifically name two structures of the orbits that are demonstraed on the modified caldwell view
    • Lesser and greater wing of the sphenoid
    • Superior margin of the orbits(orbit rims)
  67. Where should the petrous pyramids be demonstrated on the modified parietoacanthial projection of the orbits
    The pertrousl pyramids should be demonstrated within the maxillary sinuses
  68. What are the routine projections/views for thenasal bones
    • Parietoacanthial projection
    • lateral view
  69. whay would MRI not be used to determine if teh eye had a foreign body
    MRI would not be used because the foreign body might contian metal and cause hemorrhage
  70. What degree and gangle is the central ray for the modifed caldwell view of the orbits
    20 to 30 degrees caudad
  71. What projection is the Tangential view of the zygomatic arch
    Infersuperior projection
  72. Name one projection/view that is performed as a bilateral study of the zygomatic arches
    Paritoacanthial projection