Ch40 Renogram

Normally, the curves show rapid uptake (flow curve on left) and rapid drainage (function curve on right). Each kidney is plotted separately. 

• Perfusion panel - Notice that the time intervals are in seconds. Both kidneys show prompt uptake, but the right kidney doesn’t get quite as bright.
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• Drainage panel - The left kidney shows prompt drainage, but the right kidney retains the radionuclide even in the last image. 
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• Type I—normal response

• • Type II—obstructive response (high-pressure system)
• – no response to frusemide
• – Inconclusive if GFR <15mL/min

• • Type IIIa—dilated but not obstructed (low pressure/ hypotonic system)
• – stasis rather than obstruction
• – prompt elimination following frusemide injection

• • Type IIIb—equivocal response
• – languid response to diuretic
• – Repeat study with F-15

• • Type IV—delayed compensation (Homsy’s sign)
• – “double peak” response to diuretic
• – F-15 diuresis often reveal obstructed pattern