What is an effect of aging on the biodistribution of Tc-99m radiopharmaceuticals?

• A. Increased imaging clarity
• B. Stable organ function and blood flow
• C. Altered imaging results due to changes in organ function
• D. Reduced radiation absorption

Answer: (C)

As individuals age, there are notable physiological changes that can affect how radiopharmaceuticals are distributed in the body. Specifically, the biodistribution of Tc-99m radiopharmaceuticals can be altered due to changes in organ function, blood flow, and tissue composition. Aging can lead to gradual declines in organ function, such as reduced glomerular filtration rate in the kidneys or changes in liver function, which can impact the uptake and clearance of radiopharmaceuticals.

Additionally, variations in blood flow to different organs can also contribute to changes in how effectively these agents are distributed. For example, decreased perfusion in certain tissues may result in diminished imaging at those sites, potentially leading to less accurate diagnostic results. Therefore, the alteration of imaging results due to these changes in organ function as people age is a crucial consideration in nuclear medicine, making this the correct answer.