In-depth

Symptoms

Headache

Most headaches aren't caused by a serious illness, but some could be a sign of a life-threatening condition.

Tests and diagnosis

CT scan

A CT scan is an imaging test that uses X-rays to produce detailed images of the inside of your body.

MRI

MRI uses a magnetic field and radio waves to create detailed images of the organs and tissues within your body.

Jul. 21, 2010