Radiotracers in kidney imaging
What are the categories of radiotracers used in kidney imaging?
Glomerular filtration agents to measure glomerular filtration rate:
• Technetium 99 diethylenetriamine pentaacetic acid (99mTc-DTPA)
• Technetium 99 mercaptoacetyl triglycine (99mTc-MAG3)
• Iodine 131 o-iodohippurate (131I-OIH; mainly historical)
• 99mTc-MAG3 is superior to 99mTc-DTPA in patient with poor kidney function
Tubular secretion agents to estimate effective renal plasma flow:
• 99mTc-MAG3
• 131I-OIH
Tubular retention agents used for cortical imaging (has some utility particularly in pediatrics for pyelonephritis evaluation):
• Technetium 99 dimercaptosuccinate
• Technetium 99 glucoheptonate (not often used anymore)
• 99mTc-DTPA and 99mTc-MAG3 can both be used to evaluate transplant dysfunction
