Intraoperative Assessment of of Burst Wave Lithotripsy (BWL)

Sponsor

University of Washington (Other)

Overall Status

Active, not recruiting

CT.gov ID

NCT03873259

Collaborator

Indiana University (Other), National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) (NIH)

Enrollment

Locations

Arm

56.7

Anticipated Duration (Months)

Patients Per Site

0.4

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

Burst Wave Lithotripsy (BWL) is a novel method of urinary stone fragmentation that uses multi-cycle bursts of low amplitude ultrasound to induce stone fracture. This is in contrast to traditional extracorporeal shock wave lithotripsy (SWL), which employs a brief single compression/tensile cycle of high amplitude (shock) waves to achieve stone fracture. This is a single-arm feasibility study to test the ability of BWL to comminute (fragment) stones in humans.

Condition or Disease	Intervention/Treatment	Phase
Renal Calculi Ureteral Calculi	Device: Burst Wave Lithotripsy	N/A

Detailed Description

This is a two-center, single-arm, feasibility study. The two centers are located within the US and include: University of Washington (UW) School of Medicine and Indiana University (IU) Health Urology Clinic.

The investigative study will be performed in the operating room prior to a standard-of-care (SoC) ureteroscopic (URS) laser lithotripsy procedure. The subject will already be under anesthesia. Stones will be limited to ≤ 12 mm.

The study has one (treatment) arm and is approved to enroll up to 40 subjects (with the intent to treat 20 subjects). All subjects will be treated with the same output parameters for up to a maximum of 10 minutes per stone. The output parameters are nominally defined as:

350 kil0Hertz (kHz) acoustic frequency
7 MegaPascals (MPa) peak negative pressure
20 cycle pulse duration
17 Hz pulse repetition frequency

A maximum of 3 stones can be treated per subject.

Safety will be monitored by visual observation of the tissue with an ureteroscopic camera, the self-reported occurrences of adverse events, and occurrences of unplanned emergency department or clinic visits. Fragmentation will be measured by visual observation with an ureteroscopic camera and direct measure of stones removed by basket after the procedure.

Study Design

Study Type:

Interventional

Anticipated Enrollment :

40 participants

Allocation:

N/A

Intervention Model:

Single Group Assignment

Masking:

None (Open Label)

Masking Description:

Some outcomes assessors will be blinded to the treatment conditions. This will include review of video data for tissue injury.

Primary Purpose:

Treatment

Official Title:

Burst Wave Lithotripsy (BWL) for the Comminution of Urinary Tract Stones: Intraoperative Evaluation of Safety and Effectiveness

Actual Study Start Date :

Aug 8, 2019

Anticipated Primary Completion Date :

Apr 15, 2024

Anticipated Study Completion Date :

Apr 30, 2024

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Treatment Group Subjects in this arm receive the 10-minute burst wave lithotripsy intervention dose during their standard-of-care lithotripsy procedure.	Device: Burst Wave Lithotripsy Fragment upper urinary tract stones

Arm

Intervention/Treatment

Experimental: Treatment Group

Subjects in this arm receive the 10-minute burst wave lithotripsy intervention dose during their standard-of-care lithotripsy procedure.

Device: Burst Wave Lithotripsy

Fragment upper urinary tract stones

Outcome Measures

Primary Outcome Measures

Safety - Area of Tissue Injury [Day 0 - the day of the experimental procedure immediately following the acoustic procedure.]
The primary safety endpoint is the area of hemorrhage observed through direct visualization with the ureteroscope.
Effectiveness - Volume of Fragments < 2 mm [Day 0 - the day of the experimental procedure immediately following the acoustic procedure.]
The primary effectiveness endpoint is the volume fraction of stone fragments less than 2 mm relative to the original stone volume.

Secondary Outcome Measures

Safety - Adverse Event Assessment [out to 120 days post-procedure]
The secondary safety outcome is the documented occurrence of all adverse events and comparison of the incidence (rate of occurrence) to the adverse events typically associated with shock wave lithotripsy (SWL) and URS
Effectiveness - Time to Full Comminution [Day 0 - the day of the experimental procedure immediately following the acoustic procedure.]
projected time to full comminution defined as the time at which no fragments would be ≤ 2 mm

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years and Older

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Inclusion Criteria:

Individuals presenting with at least one kidney stone apparent on CT
Individuals scheduled for clinical stone removal via ureteroscopy (URS)

Exclusion Criteria:

Individuals under 18 years of age
Individuals belonging to a vulnerable group (pregnant, mentally disabled, prisoner, etc.)
Individuals with uncorrected bleeding disorders or coagulopathies
Individuals taking a clinically significant anticoagulant dose at the time of the procedure
Individuals with a calcified abdominal aortic aneurysm or calcified renal artery aneurysm
Individuals with a solitary kidney
Individuals with a comorbidity risks which, at the discretion of the physician, would make the patient a poor candidate for the BWL procedure