CT mastoid scan: purpose, preparation and results

It can show the middle ear, mastoid air cells, ear-canal region and nearby bone. The scan is sometimes called a temporal-bone CT, and its findings must be matched with symptoms, an ear examination and any hearing or laboratory tests.

The scanner takes thin cross-sectional images that make small bony structures easier to assess. A radiologist can look for fluid or soft tissue in normally air-filled spaces, erosion or remodelling of bone, fracture, and extension toward nearby structures. Those patterns narrow the possibilities but may not identify the exact cause on their own.

Some examinations are performed without contrast because bone detail is the main question. Contrast may be added when the team needs to assess inflammation, blood vessels, soft tissue or possible spread beyond the mastoid. MRI or a tissue sample may still be recommended if soft-tissue characterisation or diagnosis of a growth is required.

Tell the imaging team about pregnancy, kidney problems, allergies, current medicines and any previous reaction to contrast. Follow the appointment instructions about eating or drinking if contrast is planned. Remove hearing aids, earrings and other metal around the head when staff ask, because these can interfere with the images.

You will lie still with your head supported while the scanner acquires the pictures. The scan itself does not touch the ear. Afterward, follow any contrast-specific advice and ask when the report will reach the referring clinician. The report should be explained together with the reason the scan was ordered, not read as a diagnosis in isolation.

Seek prompt medical assessment for worsening pain or swelling behind the ear, an ear pushed outward, fever with increasing illness, new facial weakness, severe dizziness, sudden hearing loss, persistent vomiting, severe headache, neck stiffness, confusion or unusual drowsiness. After contrast, emergency help is needed for breathing difficulty, swelling of the face or throat, collapse, or another rapidly developing severe reaction.

Ask whether the examination will cover both temporal bones, whether contrast is planned, and what specific problem the radiologist is being asked to assess. Once the report is available, clarify whether the finding explains your symptoms, whether an ear specialist, hearing test, MRI or biopsy is needed, and what change should bring you back sooner.