What is the purpose of performing sinus radiography with the patient in an upright position?

The purpose of performing sinus radiography with the patient in an upright position is primarily to demonstrate air/fluid levels within the sinuses. When the patient is upright, any fluid accumulation, such as mucus or pus, will settle at the lowest point of the sinus cavity. This positioning allows radiologists to better visualize the presence of air-fluid levels, which are indicative of conditions such as sinusitis.

When the patient is standing or sitting upright, gravity helps to position any fluid distinctly below the air in the sinuses, making it easier to identify abnormalities on the radiograph. This aspect is crucial in diagnosing sinus conditions accurately, as recognizing this air/fluid interface can influence treatment decisions. The upright position is therefore foundational to enhancing the diagnostic quality of the sinus images.