A cyclotron is a particle accelerator used to produce medical isotopes needed for PET scans. It uses a combination of high-powered magnets and alternating voltage to convert stable atoms into radioactive isotopes. This process involves spinning charged particles in ever-expanding circles until they strike a target. The cyclotron’s magnets pull the charged particles in a circular motion, while the alternating current charges particles with energy each time they cross a threshold down the middle of the circular path. When the particle beam interacts with the stable atom in the target, a nuclear reaction occurs creating radioactive isotopes.

Tiny doses of radioactive isotopes are injected into patients or research study subjects who undergo Positron Emission Tomography (PET) scans. The isotopes act as tracers that the scanner detects in the body. For clinical use, the scanner can diagnose or detect cancerous growths, brain diseases such as Alzheimer’s disease and coronary heart disease. Visualization of cancer then allows physicians to stage the cancer and plan treatment. At The Neuro isotopes are used mainly for research protocols such as drug testing or investigating functions and diseases of the nervous system.

Designed and operated to meet or exceed the highest federal safety standards, the facility is regulated by the Canadian Nuclear Safety Commission and Health Canada, and conforms to The Neuro’s health and safety policies.

Access to the cyclotron and the associated laboratories is tightly controlled through a variety of safeguards. Specialized air and waste handling systems guard against accidental releases of radioisotopes outside the facility. Lab work with radioisotopes takes place in sealed and shielded hot cells designed to contain spills. Because the isotopes produced in the facility are designed to be injected into humans, they do not last very long and decay to negligible amounts in a matter of hours.

The risk for a member of the public to be accidentally exposed to medical isotopes is extremely low.

The main isotope for clinical use, fluorine 18, has a half-life of 110 minutes. For research, we mainly use Carbon 11 with a half-life of just 20 minutes. This means that radioactivity decays rapidly. The doses produced are designed to be safe for injection into patients and research study subjects.

The facility is designed so that radiation produced by the cyclotron is contained within the controlled areas that are accessible only to authorized personnel. Heavy shielding is incorporated into the building walls to keep radiation to normal background levels at all times outside the facility and to ensure that there are no radiation exposure risks to any workers, members of the public or the environment. Personnel working in the cyclotron unit, as well as all staff working with radioactive chemicals wear monitoring equipment (badges) that measure exposure to radioactivity. Badges are turned in and checked regularly. The packaging and transport of the radioactive substances for delivery to local hospitals is done safely in accordance with Transport Canada regulations for the transport of dangerous goods (TDG, class 7).

For more information on isotopes visit the Health Canada website.

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