oxygen-15

Oxygen-15 is a radioactive isotope of oxygen with a half-life of approximately 2 minutes. It is primarily used as a radiopharmaceutical in positron emission tomography (PET) imaging. Oxygen-15 can be incorporated into various molecules such as water ([^15O]-H₂O), carbon monoxide ([^15O]CO), and molecular oxygen ([^15O]O₂) to serve as tracers for measuring physiological parameters including regional cerebral blood flow, myocardial perfusion, lung perfusion, and tissue oxygen consumption. Its mechanism of action relies on its decay by positron emission; the emitted positrons annihilate with electrons to produce gamma rays detectable by PET scanners. Due to its short half-life and free diffusibility (especially in the form of [^15O]-water), it allows for rapid sequential imaging but requires on-site cyclotron production due to rapid decay[1][3][6]. Oxygen-15 labeled water is considered the gold standard for quantitative myocardial blood flow studies[3]. The isotope itself is metabolically inert when used in these forms.

Other names

O-15O15O 1515O[^15O]Oxygen 15 radioisotopeOxygen15 radioisotopeOxygen-15 radioisotope