Comparison of Laser Lithotripsy With and Without Steerable Ureteroscopic Renal Evacuation (SURE)

• SURE (Device): The SURE stone evacuation procedure is a technique intended to more easily and completely remove a kidney stone during a kidney stone treatment. The urologist first uses a laser to break the kidney stone into small pieces. Then with the SURE procedure, the pieces are gently vacuumed out of the kidney instead of retrieving the pieces one-by-one with a basket or leaving them to pass naturally in the urine. Basketing is allowed and might be used with the SURE procedure, if needed to remove some small stones.
• Standard Ureteroscopy (Basketing) (Device): This is a treatment in which the urologist uses a laser to break a kidney stone into small pieces and then uses a tool called a basket to retrieve the pieces one at a time.

Primary outcomes

• Stone Free Rate (SFR) - Zero Fragments [30 Days]: The primary efficacy endpoint is the SFR, where stone free status is defined as zero residual fragments at 30 days observed on non-contrast CT (NCCT) (1.25mm slice thickness) by blinded central reviewer(s). The SFR is calculated by determining the number of subjects in each treatment arm with a stone free status of zero fragments and dividing that by the total number of subjects treated in the respective treatment arm.

Secondary outcomes

• Residual Stone Volume (RSV) [30 Days]: A continuous quantitative measure of remaining stone volume following intervention, assessed via post-procedural imaging on NCCT (1.25mm slice thickness) by blinded central reviewer(s).
• Stone Clearance (% Reduction in Stone Volume) [30 Days]: Percent reduction (\[Baseline stone volume- 30-Day stone volume\] / Baseline stone volume) in stone volume following intervention, assessed via post-procedural imaging on NCCT (1.25mm slice thickness) by blinded central reviewer(s). A positive result indicates a decrease in stone volume removed during the procedure; a negative value indicates an increase in stone volume following the procedure.

Sex: All, ages: 18 Years to any

Inclusion Criteria:

* Candidate for ureteroscopy with laser lithotripsy;
* Presence of renal stone(s);
* Be willing and able to return for all study-related follow up procedures; and,
* Have been informed of the nature of the study, agreeing to its requirements, and have signed the IRB approved informed consent.

Exclusion Criteria:

* BMI > 45;
* Significant comorbidities;
* Bladder, ureteral or kidney abnormalities;
* Pregnant individuals; or
* Unable to meet the treatment and follow up protocol requirements.

Participant flow

Outcome results

• Stone Free Rate (SFR) - Zero Fragments (Primary), Number, % subjects: SURE 48; Standard Ureteroscopy (Basketing) 49
• Residual Stone Volume (RSV) (Secondary), Mean, mm^3: SURE 14.3 +/- 30.9; Standard Ureteroscopy (Basketing) 70.2 +/- 144.9
• Stone Clearance (% Reduction in Stone Volume) (Secondary), Mean, percent reduction (%): SURE 97.1 +/- 5.4; Standard Ureteroscopy (Basketing) 93.3 +/- 11.7

Adverse events

Time frame: 30 Day

Serious adverse events by term

Other adverse events by term

• Study Protocol and Statistical Analysis Plan (PDF, 2023-01-26)