What is a nuclear scan?

A nuclear scan is an imaging test that uses imaging technology and trace amounts of radioactive materials, called radiotracers, to diagnose and monitor diseases and treatments. Nuclear scans can show the structure and function of most body organs and tissues. Doctors use nuclear scans to evaluate and treat a wide variety of conditions, including cancer, coronary artery disease, and seizure disorders.

In a nuclear scan, the radiotracer illuminates organs and tissues by releasing radiation inside the body, instead of targeting the radiation from outside the body, as with X-rays. Nuclear scans are based on your body’s ability to absorb, or take up, certain substances. Body tissue that is infected, inflamed, or growing abnormally (such as a cancer cell) absorbs the substance differently—usually more—than other tissues. Special cameras (nuclear scanners) detect the radiation once it is absorbed into your body.

Nuclear scans go beyond showing the structure of your body. They provide important information about how organs and tissues are functioning that generally cannot be learned using other imaging methods. Nuclear scans can also identify some diseases and conditions in their earliest, most treatable stage. 

A nuclear scan is only one method used to diagnose and treat various diseases and conditions. Discuss all of your testing options with your doctor to understand which options are right for you.  

Types of nuclear scans

General types of nuclear scans include:

  • Gallium scan looks for infection, inflammation or cancer in certain organs or in the whole body.
  • PET scan (positron emission tomography) evaluates such functions as blood flow, oxygen use, and glucose metabolism. Doctors often use PET scans to evaluate cancer, heart disease, and nervous system problems to see how they are responding to treatment.
  • PET/CT is a combination PET and CT scan to diagnose, stage or restage cancer and evaluate the treatment plan. PET/CT scans create three-dimensional (3-D) pictures to pinpoint the exact location of cancer and other diseased tissue.
  • SPECT scan (single photon emission computed tomography) creates 3-D images to show how blood flows to tissues and organs. SPECT scans are particularly useful in diagnosing heart and blood vessel conditions.

Specific types of nuclear scans include:

  • Bone scan checks for infection and bone cancer.
  • Gallbladder scan checks gallbladder function and helps find the cause of upper abdominal pain.
  • MUGA (multiple gated acquisition) scan and other nuclear heart scans evaluate the pumping of the heart, how blood is flowing to the heart muscle, and if heart muscle is damaged.
  • RBC scan (red blood cell) helps to identify bleeding along the gastrointestinal tract
  • Renal scan checks kidney function.
  • Thyroid scan checks for hyperthyroidism (overactive thyroid), thyroid cancer, and thyroid nodules.

Why is a nuclear scan performed? 

Your doctor may recommend a nuclear scan to screen, diagnose and monitor diseases, disorders and conditions in almost any part of the body. Examples include:

  • Aging and degenerative diseases and disorders including dementia and Alzheimer’s disease
  • Cancer and tumors including thyroid cancer, ovarian cancer, liver cancer, colon cancer, Hodgkin lymphoma (Hodgkin’s disease), non-Hodgkin lymphoma, and bone cancer
  • Cardiovascular disease including coronary heart disease
  • Gastrointestinal disease including inflamed gallbladder, bile duct blockages, cirrhosis, hepatitis, and infections
  • Kidney diseases including infection, injury, or obstruction such as from a kidney stone
  • Neurologic conditions including seizures, head trauma or injury, stroke, and memory loss
  • Seizure disorders including epilepsy
  • Thyroid disorders including hyperthyroidism (overactive thyroid) and thyroid nodules

Who performs a nuclear scan?

A radiologic technologist may perform a nuclear scan under the supervision of a doctor. A radiologic technologist is a healthcare provider who performs imaging procedures and takes care of patients during procedures.&