Nitrogen-13 is a positron-emitting radioactive isotope with a half-life of approximately 10 minutes. It is widely used in positron emission tomography (PET) imaging to assess myocardial blood flow in patients with suspected coronary artery disease.
Explain why Nitrogen-13 must be synthesized in a cyclotron located directly within or immediately adjacent to the medical facility, rather than being supplied by a centralized commercial manufacturer.