Computed tomography of the head

Computed tomography of the head (also known as a head CT) is a diagnostic imaging procedure that uses special x-ray equipment to obtain images from different angles around the skull. The computer processes this information to create two-dimensional cross-sectional images, which can be combined to create a three-dimensional image of the inside of the head. This procedure is used to diagnose diseases and conditions such as brain tumors, intracranial hemorrhage, and skull fractures.

Procedure

The patient lies on a narrow table that slides into the center of the CT scanner. The x-ray tube rotates around the patient's head, taking a series of images from different angles. These images are then processed by a computer to create cross-sectional images of the brain and skull. The entire procedure usually takes less than 30 minutes.

Uses

Head CT is used to diagnose a variety of conditions affecting the brain and skull. These include brain tumors, intracranial hemorrhage, skull fractures, hydrocephalus, brain abscess, and sinusitis. It can also be used to guide biopsy procedures and to plan radiation therapy.

Risks

While a head CT is generally safe, it does expose the patient to a small amount of radiation. However, the risk of developing cancer from a single CT scan is very small. Other risks include allergic reactions to contrast material and kidney damage in patients with pre-existing kidney disease.

Alternatives

Alternatives to a head CT include magnetic resonance imaging (MRI) and ultrasound. These imaging techniques do not use radiation and may provide more detailed images of certain types of brain tissue.

See also

• Computed tomography
• Magnetic resonance imaging
• Ultrasound