Brody's Surgery went well and appears the internal stent was indeed partially occluded.

Brody is out of surgery and in recovery room now.   Surgery went well.   The interventional radiologist injected dye during the procedure to see if it could make it through Brody's internal stent that was suspected to be occluded and the culprit of  Brody's sudden worsening kidney function.   Very little of the dye made it through the internal stent.   So sounds like it is partially occluded.   Hopefully with the external nephrostomy tube in place now,  Brody's kidney makes a rapid recovery. Time will tell.