CT vs PET Scan: What’s The Difference?

CT vs PET Scan: What’s the difference? One takes just minutes to complete and the other up to two hours. You doctor or care team determines which test will provide the information needed for your health concerns. Let’s learn more.

Computed Tomography (CT) ScansCT Scan.

A CT scan is a common imaging tool to show detailed images of the inside of your body. A small amount of radiation is used to display this X-ray technology and a contrasting material is used to highlight certain areas.

The X-ray uses a computer to show 2-dimensional images of the inside of your body. A CT scan is completely painless and can take as little as 5 minutes to complete as the CT scanner takes pictures of your body from different angles.

Why Physicians Order A CT Scan

A CT scan will diagnose many health conditions. They include: cancer cells, infections, chronic vascular conditions, and injuries like fractured bones. They can show blood vessels, organs, and soft tissues. It is possible to locate the size and location of tumors, blood clots, heart disease, a liver mass, and internal bleeding.

Your doctor may want to check for abnormalities in your brain, neck, spine, chest, or abdomen. It allows physicians to make critical medical decisions quickly and is used in many hospitals for a timely diagnosis since the results are immediate.

Positron Emission Tomography (PET) Scans

With this type of imaging tool, a small amount of radiation is used to highlight the 3-D images, however this test can last up to 2 hours. It is a form of nuclear medicine imaging.

It shows images of the body on a molecular level to find illnesses and see their progression. They are most commonly used to detect illnesses earlier than other tests and can monitor the progression. A small amount of a radioactive tracer is injected into the body. The tracer will highlight tumors, inflamed areas, and cancer cells which takes approximately an hour prior to the scan.

Why Physicians Order A PET Scan

A PET scan can diagnose:

  • Cancer and heart disease
  • Brain disorders like Alzheimer’s disease, Huntington’s disease, and seizures
  • Cancer at an early stage
  • Disorders of the central nervous system
  • Blood sugar, blood flow, and oxygen use
  • An organ that might not be functioning correctly

A PET scan can take two days to get results.

Main Differences

Materials: CT passes X-ray through the body, whereas PET uses radioactive materials.

Different Timing: CT takes minutes, whereas PET can take 2 to 4 hours (or longer).

Radiation: no radiation stays in the body with a CT scan, whereas a small amount remains in the body with PET scan.

Cancer detections: PET scans can show cancer at its earliest stage.

Contact Alabama Coastal Radiology if you have additional questions concerning CT vs PET scans.