SIDEBAR 2.1

Radionuclides Used in Nuclear Medicine

Radionuclides (also called radioisotopes) are chemical elements that are radioactive. The nucleus of an unstable radionuclide becomes stable by emitting energy, such as alpha or beta particles. The nucleus may also emit energy in the form of electromagnetic radiation known as gamma rays. Although radionuclides can be found in nature, all radionuclides used in nuclear medicine are produced in linear accelerators, cyclotrons, or nuclear reactors. Each radionuclide has unique properties that make it useful for certain diagnostic and therapeutic tools. The table summarizes commonly used radionuclides for imaging and therapy.

Commonly Used Radionuclides for Imaging and Therapy

Radionuclide

Half-Life

Type of Radiation Emitted

Imaging Technique Used

Imaging

 

 

 

Carbon-11

20.33 min

positron

PET

Nitrogen-13

9.97 min

positron

PET

Oxygen-15

2.04 min

positron

PET

Fluorine-18

109.75 min

positron

PET

Technetium-99m

6.02 hours

gamma

SPECT

Indium-111

2.8 days

gamma

SPECT

Iodine-123

13 hours

gamma

SPECT

Therapy

 

 

 

Iodine-131

8 days

beta

 

Yttrium-90

2.7 days

beta

 

unique partnership among the national laboratories, academia, and industry (Section 2.1). They have collaborated to develop:

  • nuclear reactors and particle accelerators that produce radionuclides;

  • chemical processes to synthesize radiopharmaceuticals that can be used for imaging and treatment; and

  • instruments that can detect radiation emitted from the radionuclides that accumulate in the human body.

According to data from the Center for Medicare and Medicaid Services (CMS), nuclear medicine plays an essential role in medical specialties from cardiology to oncology to neurology and psychiatry and is a $1.7 billion industry. The Society of Nuclear Medicine estimates that 20 million nuclear



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement