11. Mixed Message

A couple of months ago I underwent a renal scan to further determine the extent of this damage. I was given a tiny dose of a radioactive isotope and then for almost an hour I had to lay still while a medical geiger counter tracked the flow of this isotope as it passed through the kidneys.  I was watching the screen and it looked like my right kidney was not processing as quickly as the left.  

This is what my urologist emailed me about the scan:

"Your renal scan showed 62% function in the left kidney and 38% function in the right kidney. The right kidney has some sluggish drainage, but no obstruction.  It is likely from the chronic dilation of the ureter and collecting system."

And this is from the radiologist's interpretation:

"The arterial phase reveals prompt perfusion of the left kidney but diminished perfusion of the right kidney.  Split renal function at two minutes reveals 62% of the total perfusion to be present in the left kidney and 38% and [sic] the right kidney.  There is prompt unobstructed excretion by the left kidney. There is somewhat delayed and prolonged clearance of activity from the right collecting system."

The urologist would have me believe that both kidneys are functioning below normal--"function" being the key word here.  In fact, since 62 + 38 = 100, it would appear that my renal system operates as the equivalent of one healthy kidney. Doesn't sound good, does it?

But the radiology report suggests a different interpretation, that the left kidney is responsible for 62% of the total work done during that hour, and the right for 38%.  A normal left ovary, in other words, and a problematic but unobstructed right ovary. Here the key word is "perfusion." Is there a difference between perfusion and function?  

I'll go with the radiologist and schedule a second opinion with a second urologist.

My family practice doctor is more interested in a blood test called creatinine and the "glomerular filtration rate" derived from creatinine level, are the usual markers used to define kidney health.  My creatinine level measured in January was significantly elevated, raising concern about permanent kidney damage. But that was before any procedure, when hydronephrosis was present; a few weeks after the stone was removed, the creatine returned to normal levels.