Extra-Oral Imaging Flashcards
The zone of sharpness in a pano is called what?
Focal Trough
*images nearest to the middle of the focal trough are clearest
Why should you not make linear or angular measurements using a panoramic radiograph?
They are inherently distorted in both size and shape
*distortion due to beam angulation, X-ray source to object distance, path of rotational center, and position of object in focal trough
Objects that are located between X-ray source and center of rotation cause what?
Ghost images
*usually at a higher level due to beam angulation
What are 3 other types of extra oral imaging that can be used instead of panoramic radiographs to get various views of the skull?
- CT (Computed tomography)
- MRI (magnetic resonance imaging, image of organs)
- PET (positron emission tomography, uses tracer)
The beam of what imaging technique is captured on an amorphous silicon flat panel or image intensifier/charge-couple-device (CCD) detector and like a CT except it has a cone shaped beam rather than fan like?
Cone Beam Scan
In a panoramic, seeing large amounts of the vertebrae on either side of the image means the patient was likely what?
Too far forward
Not seeing any or very little vertabrae on the panoramic image means the patient was likely what?
Too far back
Seeing a radiopacity on the opposite side, roughly 11 degrees above an ear-ring is likely what?
Ghost image
Large radiopacity in a “pyramid” shape is likely what?
Lead apron artifact
A flat curve of spee with the vertebrae sloping off the image and a cone shaped radiopacity over the centrals is likely due to the patient being what?
Slumped
A drastic curve of spee is likely due to the patient being what?
Having their chin tipped down
the condyle being higher on one side than the other, and the image slanting is likely due to the patient being what?
Head twisted
