Cavernous sinus thrombosis - Diagnosis 

To confirm that you have cavernous sinus thrombosis, your GP may refer you to have the tests described below.

• A lumbar puncture, where a sample of fluid is taken from your spinal cord. This may show signs of infection. 
• A computerised tomography (CT) scan of your sinuses, eyes and brain. X-rays build up a detailed picture of your head to rule out other causes, such as an abscess.
• A magnetic resonance imaging (MRI) scan of your brain. A magnetic field and radio waves build up a detailed picture of your brain.

If it is thought that an infection is responsible for your symptoms your GP will take a sample of your blood and samples of fluid, mucus or pus from your throat and nose to send to the laboratory for testing.