This picture-taking technology, called cross-sectional imaging, allows the radiologist to look at different levels or slices of the temples or sides of the skull bone using a rotating X-ray beam. The radiologist is able to check each slice for injury or bony abnormalities.

The exam may include injecting an iodine substance in the vein. Diabetic patients and those with allergies must inform the radiology staff and may need clearance from their doctor before the exam. Blood tests may also be required prior to the administration of contrast materials. Patients whose exam includes an injection may not eat or drink anything four hours before the test. During the injection the patient may experience a warm sensation throughout the body and a metal taste in the mouth. This is normal.

This procedure is done in two positions. For both, the head is positioned in a holder, and the patient is asked to lie very still. For the first position, patients lie on their backs with the arms at the sides. For the second position, the patient lies on the stomach with the head resting on the chin. Only the head is covered by the scanner, and the scanner is open at the back and the front, allowing the patient to see out. The technologist is able to see and hear the patient throughout the 30-minute exam.