What Is a Sinus CT Scan?

A sinus CT scan is an imaging test that uses advanced x-ray technology to produce a detailed image of the sinuses, hollow passages of indeterminate function that are found within the skull. Typically, the purpose of a sinus CT scan is to aid a doctor in diagnosing a medical condition involving the sinuses, such as chronic sinusitis, cysts, polyps, and so forth. During this usually brief procedure, a patient lies very still on a movable table, which is then slid into a scanning device. As with all CT scans, a sinus CT scan exposes a patient to radiation, and thus it is usually only ordered for those with severe or long-lasting sinus problems.

During a sinus CT scan, a scanner takes a number of x-ray images of a patient’s head, which are then put together via computer to create a detailed illustration of the patient’s sinuses. As it is impossible to see the sinuses with the naked eye, this type of scan can be extremely useful in identifying difficult-to-diagnose sinus conditions. It may show, for instance, that a sinus or the bone surrounding a sinus has become infected. Alternatively, it might reveal that a structural abnormality or a growth such as a tumor or cyst is causing the blockage of a sinus. Once a doctor has verified or ruled out the presence of a sinus condition through this type of scan, he can create an appropriate treatment plan.

Normally, a sinus CT scan takes around 15 minutes to complete. During this time, the patient must lie motionless on a sliding table. The table is slid into the scanning mechanism, which captures a number of x-ray images of the head. These images may be printed out or studied on a computer screen. Metal objects such as jewelry or hairpins cannot be worn during a scan, as they can affect the quality of the images produced by the scanner.

Like all imaging tests which use x-rays, a sinus CT scan briefly exposes the individual being tested to radiation, which can increase one's risk of cancer. Consequently, most doctors avoid ordering this test unless a patient’s sinus problems seem critical, or if his condition has recurred on numerous occasions or has not responded to multiple forms of treatment. Many medical experts argue, however, that the level of radiation exposure associated with this procedure is so minor that the potential benefits of conclusively diagnosing a patient’s sinus condition outweigh the procedure’s risks.