Author Question: What criteria indicates a properly positioned PA skull? petrous pyramids half fill orbits petrous ... (Read 56 times)

berenicecastro · **on:** Jul 17, 2018

What criteria indicates a properly positioned PA skull?

petrous pyramids half fill orbits
petrous pyramids fill entire orbits
petrous pyramids fill three quarters orbits
petrous pyramids project superior to the orbits

Question 2

All of the following describe the primary beam except:

attenuated
travels in a straight path
non-attenuated
emitted from the tube window and collimators

ms_sulzle · **Reply #1 on:** Jul 17, 2018

Answer to Question 1

petrous pyramids fill entire orbits

Rationale: The OML should be aligned perpendicular to the IR. With the chin tucked the petrous pyramids will shift more superior and fill the orbits entirely. Petrous pyramids should not push superior to the top of the orbits, this would indicate overflexion of the part.

Answer to Question 2

attenuated

Rationale: The primary beam is emitted from the tube directly. This has not yet been attenuated. The photons are still traveling in a straight path.