A CT scan uses X-rays and computers to make images of the body. It can sometimes help doctors diagnose headaches and their causes.

You might need one if you have headaches daily or almost every day or have a sudden onset severe headache. Doctors can’t diagnose migraines with the test, though.

How Does a CT Scan Help?

The test can help your doctor rule out other causes of your pain, such as:

A brain tumor
An infection of the brain, called an abscess
The buildup of fluid in the brain, a condition called hydrocephalus
A sinus blockage
Injuries
A bulging, weak part of a brain artery, called an aneurysm, or bleeding in the brain.

Reference, WebMD, https://www.webmd.com/migraines-headaches/making-diagnosis-ct-scan#1, consulted on September 11, 2019