What kind of kidney stone from ultrasound

[villandra]

I have screenshots/ exported images from a renal ultrasound done 8/2011, a CT scan done 7/2011, and a CT scan done 12/2009.    The 2011 images are of a kidney stone in my left kidney, and the images from teh CT scan in 12/2009 are of a kidney stone in my right kidney that was elsewhere when the CT scan in 7/2011 was done.   http://community.webshots.com/user/villandra  Current stone in the left kidney, and former stone in right kidney, are in separate photos, and photos of the passed kidney stone from the right kidney are in yet another folder.  

Is it possible to discern what sort of a kidney stone is in my left kidney, from its appearance in the CT scan and the ultrasound?

Radiologist's opinion on the ultrasound is it "might" be a kidney stone, though it is in the same location as the actual kidney stone on the CT scan.  

There are several reasons for the mystery.

The kidney stone that was passed from the right kidney in 7/2011, images of which appear in a folder in Webshots, was 2 mm, and entirely of calcium compounds.   It measured 3 mm in the CT scan.  

The stone in the left kidney is called a "punctate" stone in 7/2011, and looks no bigger than the stone that was originally in the right kidney.  

On the ultrasound the stone in the left kidney measures 7 mm.   Radiologist didn't question its size, only if it is really the kidney stone.  

Shouldn't calcification of any sort in the kidney be brighter than the 7 mm O shaped object in the scan?   This leads me to wonder if possibly it is atleast partially a different substance such as uric acid.  

The 2 mm kidney stone that I passed in 7/2011 appeared in a CT scan done in 12/2009 and the kidney stone that is now in the left kidney did not.   Neither stone appeared in a CT scan done in 6/2004, so neither stone has been growing for "a very long time".  This means that the kidney stone in my left kidney has had only half as long to grow as the one in my right kidney.   How then should the younger stone be three times as large?   Again the notion that it's not of the same ingredients provides a possible explanation.    

Do uric acid stones look as bright in ultrasound as calcium stones?  

To humor the radiologist, what else is it likely to be besides the kidney stone that showed in the same place in the CT scan?  I've never been told I have cysts, and I think they look like dark blobs on a renal ultrasound, never mind not looking entirely shiny.  

[ChitChatNine]

The only way I know of is to have the stone sent to a good lab to see what it's made of after you pass it (them).

C~

[el_em_en_oh]

It's REALLY difficult to discern kidney-stone chemical composition from an ultrasound, sonogram, CT, IVP, KUB or any other type of renal scan.

The only really definitive way to tell what a stone is made of (chemically), is to do a physical test after one is passed or removed.

Uric-acid, calcium, calcium-oxilate & cystine are the most common types of stones, with cystine being the least common. There ARE other combinations of stone make-up, but they become increasingly less common once these 4 types are ruled out.

Have you ever passed a stone, and if so, did you save it? If so, you may be able to give the stone to your urologist for pathology to determine chemical make-up.

Good luck to you.

LMNO

[Kaneda2112]

You can see what actualt renal sonograms look like here (http://www.sonoguide.com/renal.html) but I don't see any indication that they can tell the difference in their composition -

"Renal or ureteral stones may be seen on ultrasonography in the patient with acute renal colic.  Look for bright objects that cast a shadow within the kidney (Figures 8 – 12).  If you can, follow the dilated ureter down toward the bladder.  A bright object that casts a shadow within the ureter or at the junction of the bladder is consistent with ureteral nephrolithiasis.  It is often difficult to identify ureteral stones."