Why is it important to perform quantitative studies using isotopes with shorter half-lives first?

When performing quantitative studies in nuclear medicine, using isotopes with shorter half-lives first is critical because these isotopes decay more rapidly, thereby reducing the potential for interference in the measurements. Isotopes with shorter half-lives emit radiation and lose their activity more quickly, which minimizes the background radiation levels and the likelihood of changes in radiotracer distribution over time. This rapid decay allows for more precise timing of imaging and measurements, ensuring that the data collected reflects the true biodistribution of the isotope during its peak activity.

In contrast, isotopes with longer half-lives remain active for an extended period, which can lead to issues such as decay during the study, changes in tissue uptake over time, and increased background radiation, all of which could compromise the accuracy and reliability of the results. Therefore, prioritizing shorter half-life isotopes enhances the clarity and precision of diagnostic imaging and therapy applications in nuclear medicine.