Extraoral Radiography Flashcards
Projection of the Central Ray
The _____ is directed perpendicular to the plane of the film in the horizontal and vertical dimensions from a source 91 to 102 cm (_____) away.
• The source should be coincident with the mid-sagittal plane of the head at the level of the bridge of the nose. For cephalometric applications the distance should be 152.4 cm (_____) between the x-ray source and the mid-coronal plane
central ray
36 to 40 inches
60 inches
Projection of the Central Ray
_____ [ cassettes or plates]
For cephalometric and skull views: 20x25 cms (_____)
For _____ views 13x18 cms (_____)
image receptors
8x10 inches
lat oblique
5x7 inches
PA skull projection
• The image receptor is placed in front of the patient, perpendicular to the _____ plane and parallel to the _____ plane
• The patient is placed so that the Canthomeatal line is _____ to the image receptor .
midsagittal
coronal
perpendicular
PA Ceph projection
• The image receptor is placed in front of the patient, perpendicular to the _____ plane and parallel to the _____ plane
• The patient is placed so that the Canthomeatal line forms a _____ angle with the horizontal plane and the _____ is perpendicular to the image receptor. In the PA skull projection, the CM line is _____ to the image receptor .
mid-sagittal
coronal
10-degree
frankfurt plane
perpendicular
Lateral cephalometric projection
• The image receptor is positioned parallel to the patient’s _____ plane. The site of interest is placed _____ the image receptor to minimize distortion.
• In cephalometric radiography, the patient is placed with the left side toward the image receptor, and a _____ at the tube head is positioned over the _____ aspect of the beam to absorb some of the _____ and allow visualization of _____ of the face.
midsagittal toward wedge filter anterior radiation soft tissues
Lateral cephalometric projection
• Resultant image
• _____ magnification of left
and right sides
• Structures close to the _____ plane (e.g., the clinoid processes and inferior turbinates) should be nearly _____.
uneven
midsagittal
superimposed
Submentovertex projection
• AKA _____ projection
Most _____ projection
base
complicated
Submentovertex projection
• Check to see the _____
• Buccal and lingual cortical plates of the mandible projected as _____ opaque lines
symmetry
uniform
Submentovertex projection _____ view
Reduce exposure to _____ of normal in order to clearly see the zygomatic arches
jug handle
one-third
Occipeto-Menton projection
• AKA :_____
• CM plane forms _____ angle (upwards) with the horizontal plane.
_____ CT
waters projection
+37 degrees
poor man’s
Lateral oblique projection
• The image receptor is placed against the patient’s cheek on the _____ and centered in the _____ area. The lower border of the cassette is parallel and at least _____ below the _____ of the mandible. The head is tilted towards the side being examined, and the mandible is _____.
• The central ray is directed toward the _____ region from a point _____ below the opposite angle of the mandible.
side of interest molar-premolar 2 cm inferior border protruded premolar-molar 2 cms
Lateral oblique projection- body
• Body of the mandible
• From _____ to _____ region
canine
molar
Lateral oblique projection- ramus
• Ramus
• Also known as _____ view
lateral ramus
Reverse Towne projection
Image receptor is placed in front of the patient perpendicular to the _____ plane and _____ to the coronal plane
C-M line is tilted down to _____ degrees
Patients mouth is open to visualize the _____
mid-sagittal
parallel
-25 to -30
condyles
Lateral Neck View
taken for _____ vertebrae (_____ vertebrae, seven has the longest body) > rules out disc _____
cervical
seven
herniations
