An ultrasound test, which doesn't use dangerous radiation, may give results similar to those of a CT scan. If you are concerned about radiation exposure, ask your doctor if you can have an ultrasound instead of a CT scan.
Children who need a CT scan may need special
instructions for the test. The child will likely need to hold his or her breath
during the scan. If the child is too young to hold still or is afraid, the
doctor may give the child a medicine (sedative) to
help him or her relax.
If your child is scheduled for a CT scan,
talk with your child's doctor about the need for the scan and the risk of
radiation exposure to your child.
CT scanners called spiral (helical) CT scanners and multi-slice (or
multi-detector) CT scanners are sometimes used for this test. Many modern
scanners are multi-slice scanners. These scanners can be used for many
conditions, such as finding
kidney stones, a
pulmonary embolism, an enlarged
prostate gland, or
atherosclerosis. These special CT scanners can:
Take better pictures of blood vessels and
organs so other imaging tests may not be needed.
Complete scans and
provide pictures in less time.
CT results are often compared to positron
emission tomography (PET) results to help find cancer. Some new scanners do
both scans at the same time.
An electron beam CT scan is another
type of CT scan that can find atherosclerosis and
coronary artery disease. An electron beam CT scan is
much faster than a standard CT scan and can take a good picture of a coronary
artery while the heart is beating. Electron beam CT scans are not widely
available. Another type of CT scanner, the multi-slice CT scan, is nearly as
fast as electron beam CT scanners and is more widely available.
CT angiogram can show two- and three-dimensional
pictures of blood vessels and the heart.
Coronary calcium scans use a CT scan to check for early signs of coronary artery disease. This test is not advised for routine screening.
A spiral CT is a way to scan the lungs more quickly than with a standard CT. Some doctors recommend this to screen for lung cancer in people who are older than 55 and who are at high risk for lung cancer.
disagree about the use of a CT method called full-body scanning to screen for
coronary artery disease and cancers. Full-body scanning is expensive, can lead
to unnecessary tests or surgery, and may increase the chance of cancer from the
radiation exposure. Most doctors do not recommend these studies unless a person
has a specific risk for a certain disease.