Which of the following positions is/are most frequently used to demonstrate the sphenoid sinuses?
1. modified waters (mouth open)
2. lateral
3. pa axial
a 1 only
b 1 and 2 only
c 2 and 3 only
d 1, 2, and 3

B

Explanation:

1 and 2 only , Mouth open and Lateral .

This are radiography projections that enables prompt projection underneath the inferior border of the orbit and equal distance from lateral orbit to lateral skull on the two sides. This further implies Fracture of right and left nasal bone and their sidelong displacement can be effectively seen. Lateral view, side of the skull lies against the film and the x-ray is projected perpendicular from the opposite side. This permits all sinuses to be effectively seen.

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