Canada's National Laboratory for Particle and Nuclear Physics Laboratoire national canadien pour la recherche en physique nucléaire et en physique des particules

Nuclear Medicine

PET Centre

Proton Eye Therapy

An Innovative Solution
to the World's Medical
Isotope Shortage



The historical focus of TRIUMF’s research has been in accelerator-based subatomic physics and the related accelerator, detector, and isotope-production technology. Not only can critical isotopes used for medical imaging and treatment be produced with TRIUMF’s accelerators (called cyclotrons), but the techniques used by subatomic physicists to peer “inside” the atom can be used to image and trace these agents inside the body to study human health and disease in research known as nuclear medicine.


The core of the TRIUMF nuclear medicine program is positron-emission tomography (PET) imaging, a technique whereby tiny amounts of radioactive nuclei known as radioisotopes are combined with certain biomolecules and injected into the body. The biomolecules can be “traced” by imaging the decay products (two photons produced by the decay of the radioactive nucleus via the emission of a positron) outside the body. PET allows the concentration of positron-labeled compounds to be determined quantitatively in space and time within the living body. PET is more sensitive than any other human imaging method, such as MRI or CT, and has now become the “gold standard” for the detection of cancer.


Many diseases alter functional relationships within and between organ systems. Functional molecular imaging enables metabolic change to be visualized. The most sensitive approach for acquiring functional images is to use biologically active molecules that are labeled with radioisotopes. The development of positron-emission tomography in the 1970s and the use of a sugar molecule labeled with 18F enabled