Diagnosis of sinus infections
Diagnosis of sinus infections
Diagnosis of sinus infections (called sinusitis) is made based on the symptoms and the physical examination. Symptoms of a sinus infection include pain and pressure in the facial region or behind the eyes, fever, purulent nasal discharge with increased post-nasal drainage and nasal congestion. If the infection is quite severe it can lead to redness and swelling of the skin near the eyes. Headaches can of course be caused by many conditions other than sinusitis, so it is important to try to confirm the diagnosis of a sinus infection
Physical examination is useful, but it is difficult to actually see into the sinuses in someone who has not had previous sinus surgery. In some cases one can actually see pus coming out of the sinuses, which confirms the diagnosis.
Since the sinuses are difficult to see, the physician may rely on x-rays to help make the diagnosis. The simplest x-ray is called a plain film and it shows some of the basic structures in the skull. However, to really get a good look at the sinuses it is often necessary to get an imaging study called a CT scan. The picture to the right shows a CT scan of normal sinuses. On this scan, the bone is white, and air shows up as black. In the healthy state the sinuses are filled with air, and therefore will be totally black. The sinuses are normally lined by a thin layer of tissue called mucosa. This mucosa should not be seen on the CT scan. With chronic sinusitis, there will be thickening on the mucosa and it will show up as an abnormal gray area on the walls of the sinuses.
The image to the left shows an example of someone with an acute sinusitis. The red air is pointing to the patient's right maxillary sinus. (On a CT scan, the patients right side is on the left side of the image). Notice that this sinus is filled with a grey material, which probably is a combination of mucous and pus. The sinus on the opposite side is completely black, indicating that it is filled with air and therefore healthy. The tip of the red arrow is actually right near the natural opening of the maxillary sinus. In his case, something is preventing the drainage of the debris and the sinus is therefore infected.
Treatment of Sinus Infections
The first line of treatment for sinus infections is a combination of antibiotics and other medical measures. There are many antibiotics available which are active against different types of bacteria. In addition to antibiotics, oral decongestants like pseudoephedrine (Sudafed) are useful. Nasal decongestants like oxymetazoline (Afrin) may be effective for a short time, but should not be used for more than several days. (Long term use of oxymetazoline can produce what is called a "rebound" effect; after stopping the medication the nasal mucosa becomes even more swollen.) If there is a history of allergies, anti-histamines may be useful.
In addition to these medicines, it is often helpful to irrigate the nasal cavity with a saline solution. This helps to keep the nasal mucosa moist and cleans the nasal cavity.
If sinus infections persist despite maximum medical treatment, surgery may be necessary.