Coronal and axial CT scans differ by imaging plane. Axial (transverse) images are horizontal slices from head to feet, showing cross-sections useful for chest, abdomen, and brain evaluation. Coronal images are vertical frontal slices from front to back, better depicting height relationships and facial, sinus, spine, or lung pathology. Modern CT can reconstruct any plane from the same raw data.

A mastoid CT scan is a high-resolution computed tomography of the mastoid portion of the temporal bone and middle ear. It produces thin-slice X‑ray images to evaluate mastoid air cells, middle ear structures, infections (mastoiditis), cholesteatoma, fractures, or chronic ear disease, and to guide surgery. The test is quick, outpatient, may rarely use contrast, and involves low radiation exposure.

Temporal bone axial and coronal refer to CT imaging planes used in high-resolution temporal bone scans. Axial images are horizontal slices from top to bottom, ideal for evaluating the petrous bone, semicircular canals and cochlea; coronal images are vertical front‑to‑back slices, useful for assessing mastoid air cells, ossicles, middle ear and facial nerve canal. Together they detect fractures, infection, cholesteatoma and congenital anomalies.

A high-resolution CT (HRCT) of the temporal bone (thin-slice axial and coronal images, typically 0.5–1 mm) is the standard CT for ear evaluation. It provides excellent bony detail to assess ossicles, cochlea, mastoid air cells, and conditions like otosclerosis or cholesteatoma. Cone-beam CT is an alternative with lower radiation; MRI complements CT for soft-tissue or nerve assessment.

For acute head injury or suspected bleeding, a non-contrast CT head is the best initial scan because it rapidly detects hemorrhage and fractures. For vascular detail (aneurysm or stroke clot), CT angiography is preferred. Contrast-enhanced CT is useful for tumors or infection. MRI provides greater soft-tissue detail but is not usually first-line in emergencies.

There are three common CT types: non-contrast (plain) CT, which images anatomy without injected dye; contrast-enhanced CT, where intravenous or oral contrast improves soft-tissue delineation and tumor or inflammation detection; and CT angiography (CTA), a rapid, contrast-based study optimized to visualize blood vessels and detect blockages, aneurysms, or vascular malformations. Used for trauma, cancer, and vascular assessment.