Sinus X-ray (limited)

What it is

The sinuses are hollow, air-filled chambers in the bones of the forehead, cheeks, and behind the nose. Because air barely absorbs the x-ray beam, a healthy sinus appears as a dark, clean space; anything that fills it — pus, fluid, thickened lining, a growth — absorbs more of the beam and turns the space grey or white. That contrast is the whole basis of the test, and it is also its limit. The film tells you a sinus is not clear; it does not tell you much about why, and it shows the small drainage channels between the sinuses poorly. Images are taken with the patient sitting upright, because fluid then pools at the bottom of a sinus and forms a visible level rather than spreading out unseen.

Why it is done

• To look for fluid or opacification in the sinuses when a sinus infection is suspected and the diagnosis is not clear from symptoms alone
• To check for a blockage in a sinus
• To look for bleeding into a sinus
• To show a growth filling a sinus, which then usually needs a more detailed study to characterize

What to expect

There is no preparation. You sit in a chair with your face against the imaging plate, and the technologist rotates your head into several set positions — chin up, forehead down, side on — because each one lines up a different group of sinuses without the others in front of them. Each exposure lasts an instant and the visit is usually a matter of minutes. Jewelry, glasses, and hairpins come off first. It is painless. A radiologist reads the images, though many of these are taken and looked at in an ear, nose, and throat office. If the films are unclear or surgery is being considered, a CT of the sinuses is the usual next step.

Questions worth asking

• If a CT of the sinuses is the likely next test anyway, is this x-ray worth doing first, and will both end up on the bill for the same episode?
• Was this taken in an ENT office with its own machine or in a hospital radiology department? The price gap for the same images is usually large.
• Is a radiologist reading the film and billing separately, or is the specialist who took it also reading it?
• If this is being repeated to see whether an infection has settled, is the repeat a full new charge?
• Sinus x-ray codes differ by how many views were taken. How many were done here, and does the bill match?