Study to Determine if There Are Specific Clinical Factors to Determine Stent Encrustation

Ureteral stent placement is one of the most common procedures performed within urology. The
stents are generally placed for relief of obstruction or to prevent obstruction following a
urological procedure. Most patients with ureteral stents will eventually form stent
encrustations. However, patients form these encrustations at dramatically different degrees
and rates ranging from no encrustation at 1 year of stenting to severe encrustation in just
a few weeks. The purpose of this study is to determine if the degree of encrustation on a
stent for any given patient can be predicted based on 24 hour urine parameters prior to
stent placement, with the stent in place and after stent removal.

Patients who will be receiving stents for other urological reasons will have a 24 hour urine
sample collected before stent placement, while the stent is in place and after the stent has
been removed. The parameters examined in the 24 hour urine collected will then be compared
to the amount of encrustation there is on the stent to see if there is any correlation
between the two.