Nuclear medicine imaging uses radionuclides or radioisotopes.

Radionuclide scan

• FSN: Radionuclide scan of X (procedure) 
• PT: Radionuclide scan of X 
• SYN: Radioisotope scan of X

For example, 

• • 
    • FSN: Radionuclide scan of peritoneal cavity (procedure)
    • PT: Radionuclide scan of peritoneal cavity
    • SYN: Radioisotope scan of peritoneal cavity

Radionuclide scan using isotopes (with other agents)

• FSN: Radionuclide scan of X using Y (procedure) 
• PT: Radionuclide scan of X using Y
• SYN: Radioisotope scan of X using Y

For example, 

• • 
    • FSN: Radionuclide scan of perfusion of liver using technetium Tc^99m^ aggregated albumin (procedure)
    • PT: Radionuclide scan of perfusion of liver using technetium Tc^99m^ aggregated albumin
    • SYN: Radioisotope scan of perfusion of liver using technetium Tc^99m^ aggregated albumin