Finding the right tests…
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Finding the right tests…
CT Scan
An ear infection that keeps coming back, or hearing loss being worked up for a cochlear implant, both lead to this scan - it images the temporal bone, the dense skull bone housing your middle and inner ear. CT is especially good here because it shows bone detail MRI can't match: erosion from a cholesteatoma, a skin-and-keratin growth linked to chronic ear infection, shows up clearly as damage to the small bones and bony ledge of the middle ear. NIDCD notes that fluid persisting in the middle ear can affect hearing and make it harder to fight new infections, and this scan looks at the underlying bone structure once symptoms suggest something beyond routine fluid buildup.
This scan images the temporal bone - the dense bone housing your middle and inner ear - including the tiny bones that carry sound and the bony canal around them. It shows bone erosion, structural detail needed before ear surgery, and the anatomy a surgeon needs to plan a cochlear implant.
The temporal bone is dense and detailed, and CT's strength is imaging exactly that kind of tissue. One review of ear imaging describes CT as excellent for delineating cortical bone, calcifications, and air, which is why erosion from a cholesteatoma or the bony changes of otosclerosis show up clearly on it. MRI, by contrast, is better suited to soft tissue and nerves in the same region - the two scans complement rather than replace each other.
A cholesteatoma is a skin-cell growth that can form in the middle ear after chronic infection, and it can slowly erode nearby bone if untreated. CT shows this erosion directly, including damage to the small bones of hearing and the bony ledge near the eardrum.
Cochlear implants restore a sense of hearing for people with significant hearing loss - NIDCD counted roughly 736,900 implanted worldwide as of December 2019, including around 118,100 in US adults and 65,000 in US children. Before surgery, this scan maps the inner ear's exact anatomy so the surgical team knows what they're working with.
CT uses X-rays, so there is some radiation exposure, generally limited given the small area scanned. Tell your doctor if there's any chance of pregnancy.
CT shows bone detail - like erosion from infection or damage to the tiny bones of hearing - better than MRI does. MRI is chosen instead when the question is about soft tissue or nerves in the same area.
It's a skin-cell growth that can form in the middle ear after chronic infection, and it can slowly erode nearby bone if left untreated. This scan shows that erosion directly.
Surgeons need to see the exact shape of your inner ear before implanting the device, since anatomy varies from person to person. NIDCD reports hundreds of thousands of people worldwide have received cochlear implants.
It can show structural causes tied to the bone of the ear, like erosion or malformation, though hearing loss has other causes this scan doesn't image. Your doctor combines it with a hearing test.
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.
Yes, CT uses X-rays, so there is some radiation exposure, though the area scanned is small. Tell your doctor if there's any chance you're pregnant.
Most temporal bone CTs done for bone detail don't need contrast. Ask your doctor or the centre whether it applies to your specific case.
Preparation is usually straightforward. Ask your doctor or the centre directly about anything specific to your appointment.