Finding the right tests…
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Finding the right tests…
CT Scan
Most sinus CT scans skip the contrast injection, so getting this version usually means your doctor suspects something has moved beyond the sinuses themselves - most often that a sinus infection has spread toward the eye socket or, less commonly, toward the brain. Clinical guidance on periorbital cellulitis notes that a plain scan is usually enough for routine sinusitis, reserving contrast for complications like periorbital cellulitis, an abscess, or intracranial spread. Contrast is also used when a mass or tumor is suspected in the sinuses, since it helps show an abnormal area against the tissue around it. This isn't the version ordered for straightforward chronic sinusitis.
This scan images your sinuses after a contrast injection highlights how infection or an abnormal growth differs from the tissue around it. It's used specifically to check whether a sinus infection has spread toward the eye socket or brain, or to characterize a suspected mass.
Most sinus CT scans don't need contrast, which is what makes this version specific. Contrast-enhanced CT becomes the imaging of choice specifically when a complication like periorbital or orbital cellulitis is suspected, since contrast helps distinguish infection confined near the eyelid from infection that has spread further and needs urgent treatment.
The eye socket sits right next to the sinuses, separated by a thin bone, which is why sinus infections can sometimes track into it and cause swelling around the eye or, in rarer cases, an abscess. Contrast makes this spread visible clearly on the scan. Less often, infection tracks toward the brain, and contrast helps show that too.
RadiologyInfo.org lists tumors among the reasons a sinus CT gets ordered. Contrast helps an abnormal growth stand out from the sinus lining and surrounding bone, which is useful before deciding whether more imaging, like an MRI, is needed for soft-tissue detail.
Routine chronic sinusitis, or sinus surgery planning, is still generally evaluated with the non-contrast scan. Ask your doctor why contrast was chosen for your specific case.
Contrast is added specifically when your doctor suspects a complication, like infection spreading beyond the sinuses toward the eye or brain, or a mass that needs to be characterized. Routine chronic sinusitis doesn't usually need it.
It highlights how infected or abnormal tissue differs from what's around it, making spread beyond the sinuses or an unusual growth easier to see clearly.
It's uncommon, but the eye socket sits right next to the sinuses separated by thin bone, so infection can track there in some cases. This scan is how doctors check for that specific complication.
This page is general information about the test, not medical advice. Your own report's reference ranges apply — please discuss your results with your doctor.
It can show an abnormal growth, and contrast helps it stand out from surrounding tissue. Your doctor may add an MRI afterward if more soft-tissue detail is needed.
Yes, CT uses X-rays, so there is some radiation exposure. Tell your doctor or technologist if there's any chance you're pregnant.
Contrast is generally considered safe with a low rate of reaction. Mention any kidney problems or previous contrast reactions to your doctor beforehand.
Ask your doctor or the centre directly about preparation, especially if you have known allergies or kidney concerns, since contrast is involved.