Ah, the coming of spring. The sun is shining, the birds are singing, and pollen is attacking your sinuses with tiny little pitchforks. What are sinuses, anyway? Simply put, they’re just hollow cavities in your face bones that connect to your nasal passage. They normally produce a small amount of mucus to moisten your airways and trap bad guys. Their hollow nature supposedly enhances your voice, too. When too many particles poke the sinuses the wrong way, they get inflamed and make more mucus to try to expel the invaders. A few of the sinuses sit within the forehead and cheek bones, which is why some people experience pain in these areas when their sinuses flair up.
CT scans let us see through facial bones and into the sinus cavities pretty well. The radiologist can tell which sinuses are affected, to what degree, and if there are complicating features like abnormal changes to the bone. Air is black on CTs, so a normal sinus full of air should just be black. I like the example below because one half of this person’s sinuses is clear, while the other half isn’t, making for a nice side-by-side comparison.
Right sided sinus disease on CT (right is left in Radiology Land)
Red is the stuffed up right frontal sinus.
Blue is normal left frontal sinus.
Green is brrraaains.
Nasal passages are yellow.
random + rad 