The shortage of medical isotopes due to of the shutdown of the Chalk River reactor is making doctors across the country desperate. The Society of Nuclear Medicine is meeting in Toronto to discuss methods for testing patients with cancer, heart disease and other conditions without using isotopes. But doctors warn that these alternatives are costly, invasive, use a lot radiation, and don’t always provide useful information. However, there is some good news. Isotopes from an Australian reactor have been approved for medical use by Health Canada, and a Russian reactor could begin producing isotopes within the next year. However, those reactors will not be able to match worldwide demand, meaning the shortage will continue for some time.