A CT scan uses a large machine shaped like a large donut to take x-rays from many angles. A computer then takes the x-rays and creates many detailed pictures of the inside of your body. Each picture looks like a slice taken from one part of your body. The computer can also create a 3-D image of the inside of your body.
Doctors use CT scans for many kinds of problems, including:
Problems in your brain and spinal cord, such as bleeding, tumors, or birth defects
Problems inside your belly, such as blocked intestines and tumors or infection in your kidneys, liver, or lungs
Problems in female reproductive organs, such as tumors in the uterus or ovaries
Abnormal blood vessels of your heart or aorta (a large artery connected to your heart)
Broken bones, particularly in your hip, back (spine), and pelvis
Torn muscles and ligaments
A CT scan exposes you to more radiation than a simple x-ray, like one of your chest. Doctors try to limit the total amount of radiation you're exposed to over your lifetime. Too much radiation can raise your chance of getting cancer.
For pregnant women and children, doctors try to use other tests unless CT is the best way to find a dangerous health problem.