Hamilton Health Sciences
Nuclear Medicine

Nuclear Medicine and Molecular Imaging

What is Nuclear Medicine?

Nuclear Medicine is an area of medicine that uses small amounts of radioactive materials to diagnose and treat a variety of diseases including several types of cancers, heart disease and other abnormalities.  The care team in the department is comprised of Nuclear Medicine Physicians and Technologists.

Procedures are safe and non-invasive and can help determine the cause of a medical problem based on the functioning of a tissue, organ, or system(s).  In some diseases, Nuclear Medicine studies can identify problems at an earlier stage in comparison to other diagnostic tests.



Nuclear Medicine Imaging

Molecular Imaging offers unique insights into the human body and enable Physicians the ability to personalize patient care.  In terms of diagnosis, molecular imaging is able to identify disease at an early stage and can determine the exact location of a tumor or abnormality often before symptoms occur.  It produces detailed pictures of what is happening inside the body and provides information that is otherwise unattainable through other imaging techniques such as x-rays or ultrasounds.


What Happens During a Nuclear Medicine Test or Scan? 

During a test or scan a small amount of radioactive material (tracer) is injected, swallowed or inhaled by the patient.  The radioactivity from the tracer is attracted to certain organs, bones or tissues and is then detectable by special cameras.  Special cameras such as a Gamma Camera, Single-Photon Emission Computed Tomography (SPECT) or Positron Emission Tomography (PET) are used during Nuclear Medicine procedures.  These devices record the radiation rays given off and then a computer is able to make an image. 


Nuclear Medicine Hospitals

  •  McMaster University Medical Centre
  •  Hamilton General Hospital 
  •  Juravinski Hospital
  •  St. Joseph's Healthcare  


Additional Resources

Please click on any of the following links to obtain further information about Nuclear Medicine: 

What is Nuclear Medicine?

Intersocietal Accreditation Commission

Society of Nuclear Medicine and Molecular Imaging


Nuclear Cardiology  

Nuclear Cardiology tests safely take pictures of the heart.  These cardiac images help to identify coronary heart disease, the severity of prior heart attacks, and the risk of future heart attacks. These highly accurate images can capture and depict the size of the heart, how it is functioning as well as assess the amount of heart muscle actually at risk of damage.  Furthermore, they enable Cardiologists to better prescribe medications, select further testing like a coronary angiogram, and determine the need for angioplasty and bypass surgery or even the use of devices to optimize treatment outcomes.


What Nuclear Cardiology Tests Can Evaluate?

  • Function of your Heart:  How well your heart pumps blood
  • Flow of Blood to the Heart Muscle:  Is there muscle damage from prior heart attack or other cause
  • Other Considerations:  Whether chest discomfort, shortness of breath, or unusual fatigue is due to heart disease
  • Scope of Disease:  Whether you have silent heart disease with one or more coronary risk factors


Additional Resources

To learn more about Cardiology Perfusion and RNA Testing, please reference our Hamilton Health Sciences patient brochures on the Forms and Brochures page; and the information links found below:

Nuclear Cardiology Services

American Society of Nuclear Cardiology


Positron Emission Tomography (PET)

PET is a type of Nuclear Medicine procedure used to examine various body tissues to identify certain conditions.

A PET scan can measure such vital functions as blood flow, oxygen use, and glucose metabolism, which helps doctors identify abnormal from normal functioning organs and tissues. The scan can also be used to evaluate the effectiveness of a patient's treatment plan, allowing the course of care to be adjusted if necessary. 

Specifically, PET studies evaluate the metabolism of a particular organ or tissue, so that information about the physiology (functionality) and anatomy (structure) of the organ or tissue is evaluated, as well as it's biochemical properties. PET may detect biochemical changes in an organ or tissue that can identify the onset of a disease process before anatomical changes related to the disease can be seen with other imaging processes.


How Does PET Work?

PET works by using a scanning device (a machine with a large hole at the center) to detect positrons (subatomic particles) emitted by a radionuclide in the organ or tissue being examined.  The radionuclide is administered into a vein through an intravenous (IV) line.

The PET scanner moves over the body.  Gamma rays are emitted from the positrons.  The camera detects where the gamma rays came from and the computer analyzes the information to create an image of where the radionuclide is accumulating.  This information shows the physicians the level of organ or tissue function.


Additional Resources

To learn more about PET scans, please click on the link below:

PETSCANS Ontario Website


 « Right Care, at the Right Time, in the Right Setting » 

Hamilton Health Sciences • Hamilton, Ontario • 905.521.2100

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