The Boston Scientific Helical Stent is a unique stent designed to improve flexibility and comfort. It is designed to conform more to the shape of the ureter (hollow tube connecting the kidney and the bladder) to ultimately improve patient comfort and decrease the need for painkillers.

Ureteral stents have been used for many years for a variety of clinical indications. Many surgeons routinely use ureteral stents after the endourologic removal of stones to facilitate in urine passage and facilitate excretion of any left over stones. There is a multitude of literature that reveals that most patients find ureteral stents to be uncomfortable. This discomfort often causes pain severe enough that patients anxiously anticipate stent removal, and often request early stent removal, and/or require use of pain medications that have many side effects and cause further discomfort to these patients.

Inclusion Criteria:

1. Male or female; female patients must be sterile, post-menopausal or willing to use birth control during the course of the study
2. 19 years of age and older
3. Having undergone Shockwave Lithotripsy-SWL, or a diagnostic ureteroscopy or uncomplicated ureteroscopy for stone removal requiring retrograde placement of a ureteral stent for an anticipated duration of between 2 and 21 days
4. Willing to sign the Informed Consent Form
5. Able to read, understand, and complete patient questionnaires

Exclusion Criteria:

1. Active, symptomatic urinary tract infection
2. Non-stone related distal ureteral obstruction or stricture
3. Clinically significant trauma or significant retained stone burden that could significantly contribute to patient discomfort
4. Ureteral perforation or trauma
5. History of bladder reconstruction or interstitial cystitis
6. Spinal cord injuries

6. Pregnant or lactating females 7. Non-stone related voiding dysfunction requiring supplemental bladder drainage tubes for more than 24 hours post operatively 8. Patients with a solitary kidney 9. Chronic use of pain or anti-spasmodic medication for symptoms other than stone related pain 10. If in the opinion of the Investigator, the patient is not a suitable study candidate.