Every now and then you meet somebody whose nose seems all stuffed up, or he complains of pains in the eyes and cheeks, and headaches. When you ask him if he has a cold, he may answer: “No, I have sinus trouble.”

What is a sinus, and why do people get “sinus trouble?” Strictly speaking, a sinus is a space filled with blood or with air. But for most people, the expression “sinus trouble” means an infection of one of the cavities connected with the nose.

There are eight or more of these small cavities in the bones of the forehead and face. There are two sinuses in the frontal bones in the forehead. The largest sinuses are in the cheek bones. And there are smaller ones that open into the back and sides of the nose.

All these cavities are lined with mucuous membranes. These membranes are continuations of those in the nose, and the secretions from the sinuses drain through the nose. There are many theories about why we have these sinuses. It may be that they help to warm the nasal passages and to keep them moist. Or, they may give more resonance to the voice, or play some part in the sense of smell. It may be that we have them simply to provide vacant spaces in the skull so it won’t be so heavy!

Sinuses may become infected after a severe cold, or influenza, or some other infectious disease. When sinuses are infected, we feel pain in the face, in the forehead, or behind the eyes, which usually comes on about the same time every day. There is sometimes a discharge from the nose.

The pain is caused by the discharge which collects in the sinus and cannot get out because the mucuous membrane which is connected with the nose is swollen. Sometimes the sinus in the cheek bone, called the “antrum,” is infected as the result of a dental disease.

An operation for sinus trouble is rarely required. When it is done, the purpose is to enlarge the opening into the nose so that better drainage will take place. The best thing to do about sinus trouble is to prevent it. Great care should be taken to avoid colds. A doctor should be allowed to treat any obstruction in the nose during the early stages, and the dentist should have a chance to treat any dental disease before it becomes serious. Also, it is probably a good idea not to live in hot stuffy rooms, which may help bring on sinus trouble.