How is sinusitis diagnosed?
Your doctor may ask you some questions about your health, for example, what your symptoms are, if you have had a cold recently, or if you have a history of hay fever, allergies, or any other medical conditions. This is often all they need to do to make the diagnosis.
Your doctor may also take a small sample of mucus or cells from the inside of your nose using a sterile cotton swab, which can be sent to a laboratory to find out what is causing the infection.
X-rays are not usually used to diagnose a sinus infection because the X-ray is not usually helpful in confirming the diagnosis.
Computerised tomography (CT) scans
CT scans will only be used if a specialist considers it is necessary to diagnose your illness. Children should only have a CT scan if it is really necessary. This is because the CT scan involves a large dose of radiation, and there is a risk this may affect the lens of the eye.
A CT scan may be recommended if:
- you have already had antibiotics for a suspected sinus infection but you still have symptoms
- you have symptoms that are not typical of sinusitis or another respiratory infection
- your symptoms are very severe
- you only have symptoms on one side of your head
- there is blood in the mucus or liquid in your nose
- the pain in your head or face is severe
- the position of one of your eyes is affected.
- Respiratory Expert Group. Therapeutic Guidelines. Respiratory: Rhinosinusitis. Melbourne: Therapeutic Guidelines Ltd; March 2012. (Accessed 27 March 2012).