Renal scan

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  • Inject 5-15 mCi
  • Cleared by glomerular filtration
  • Used to measure GFR (normal is 125mL/min)
  • May underestimate by 5-10% due to protein bond DTPA
  • Brief nephrogram phase so not used for cortical imaging


  • Inject 5-15 mCi
  • Cleared by tubular secretion (95%)
  • Used to assess tubular function
  • Protein bound
  • Can measure effective renal plasma flow (ERPF)


  • Binds renal tubules for cortical imaging
  • Evaluate for scar in pediatric population
  • Pinhole or SPECT used

Blood Flow (perfusion) - decreased perfsion is nonspecific and it can be flow related or secondary to poor kideny function with the exception of ATN where blood flow is preserved with poor function

Clearance - difficult to get standards becasue must exclude calyces

Diuretic Renogram

  • Emptying T1/2 of <10 min is normal
  • Emptying T1/2 of >20 min is abnormal

Captopril Scan

  • Use ACE inhibitor which blocks efferent vasoconstriction, decreases GFR and induce renal insufficiency
  • Monitor BP
  • Won't work if renal function is already poor
  • Unilateral is evident, bilateral is more difficult, may have to do a baseline scan

Transplant Kidney

  • Mostly to evaluate perfusion
  • ATN - prolonged accumulation of radiatracer with normal blood flow
  • Rejection - poor perfusion

Tc-MAG3 Renal Scan
Blood Flow
Pre Lasix with Delayed Clearance on right
Post Lasix with washout
Spot images with Gallbladder uptake