1. Nuclear medicine residencies are 2 years, done after 1-2 years of clinical medicine (e.g., IM).
2. Nuclear radiology fellowships are 1 year fellowships after radiology residency. Radiology residencies incorporate 6 months of nuclear medicine training + physics training. Radiologists coming out of residency can pretty much do all of nuclear medicine except for administering radioactive material treatments, e.g. MoAb for lymphoma, or I-131 for thyroid ca.