CT ORBITS WITH CONTRAST

Know more about this test

Bulging eyes that have developed gradually, eye movement that's become restricted, or a lump felt near the eye socket are among the reasons doctors reach for this scan. RadiologyInfo.org lists eyeball bulging, infection, an abnormal growth, and lost control of eye movement together as the group of orbital problems best assessed with contrast CT of the orbits. One common cause of bulging eyes is thyroid eye disease, where the immune system attacks the muscles around the eye - MedlinePlus notes that 25% to 50% of people with Graves' disease develop this eye involvement. Contrast highlights swollen muscle, an infection, or a mass against the fat and bone around it.

What this test measures

This scan images the eye socket - the muscles, fat, and structures around your eyeball - after a contrast injection highlights anything abnormal against normal tissue. It's used to look at swollen eye muscles, an infection, or a growth, and how each relates to the eyeball and optic nerve.

Understanding CT ORBITS WITH CONTRAST

What this scan looks for

RadiologyInfo.org groups four orbital problems together as reasons for contrast CT of the orbits: an eyeball that's bulging out or sinking in, an infection, an abnormal growth, and trouble controlling eye movement. Contrast makes each of these stand out clearly from the normal fat, muscle, and bone that fill the eye socket.

Thyroid eye disease

One common cause of bulging eyes is thyroid eye disease, where the immune system attacks the muscles around the eyeball, causing them to swell and push the eye forward. MedlinePlus notes that 25% to 50% of people with Graves' disease develop this eye involvement, ranging from mild irritation to, rarely, pressure on the optic nerve that threatens vision.

Infection and inflammation

An infection around the eye socket can look similar to inflammation from other causes on a plain exam, but contrast helps show how far it extends and whether it's collecting into an abscess, which changes how urgently it needs treatment.

A growth or mass

Contrast also helps outline a mass in the orbit, showing its size and how close it sits to the eyeball, muscles, or optic nerve.

Ask your doctor how these findings connect to your specific symptoms.

References

1. 1. Appropriateness Criteria: Orbits, Vision, and Visual Loss - RadiologyInfo.org https://www.radiologyinfo.org/en/info/acs-orbits-vision-visual-loss
2. 2. Graves Disease - MedlinePlus Genetics https://medlineplus.gov/genetics/condition/graves-disease/