Rb82

Rb-82, or rubidium-82, is a radioactive isotope used primarily in positron emission tomography (PET) imaging. It decays by emitting a positron to krypton-82, with a half-life of about 75 seconds, enabling rapid imaging and swift clearance from the body. The short half-life allows multiple scans to be performed in a single session with a limited radiation exposure.

Rb-82 is produced from a longer-lived parent isotope, strontium-82, in a 82Sr/82Rb generator. The generator provides on-site access to 82Rb for clinical imaging. The eluted radiopharmaceutical is typically administered as rubidium chloride and behaves chemically like potassium, tending to accumulate in tissues with high blood flow, especially the myocardium.

In clinical practice, 82Rb PET imaging is used mainly for myocardial perfusion imaging to evaluate suspected or known coronary artery disease. Its rapid half-life supports rest and stress imaging protocols within a single visit, and dynamic imaging enables estimation of myocardial blood flow in addition to perfusion. The method is advantageous when rapid results are required or when patients have limited ability to exercise, though it requires access to PET instrumentation and a 82Sr/82Rb generator.

Safety and regulatory considerations include standard radiopharmaceutical handling, shielding, and patient monitoring. The quick decay of 82Rb minimizes long-term radiation exposure, but the dose for each study must be optimized. Limitations include dependence on generator availability, relatively high positron energy which can affect spatial resolution, and costs associated with on-site production.