Clinical trial NCT03873259: Intraoperative Assessment of of Burst Wave Lithotripsy (BWL)
Official title: Burst Wave Lithotripsy (BWL) for the Comminution of Urinary Tract Stones: Intraoperative Evaluation of Safety and Effectiveness
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Renal Calculi
Ureteral Calculi
Lead sponsor: University of Washington
Sponsor class: OTHER
Collaborators: name: Indiana University
name: National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
First posted: 2019-03-13
Enrollment: 40
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: TREATMENT

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.

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.

Eligibility criteria: 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

Primary outcomes:
measure: Safety - Area of Tissue Injury
timeFrame: Day 0 - the day of the experimental procedure immediately following the acoustic procedure.
measure: Effectiveness - Volume of Fragments < 2 mm
timeFrame: Day 0 - the day of the experimental procedure immediately following the acoustic procedure.
Secondary outcomes:
measure: Safety - Adverse Event Assessment
timeFrame: out to 120 days post-procedure
measure: Effectiveness - Time to Full Comminution
timeFrame: Day 0 - the day of the experimental procedure immediately following the acoustic procedure.
Other outcomes:
Locations:
city: Carmel
country: United States
facility: IU Health North Hospital
state: Indiana
city: Seattle
country: United States
facility: University of Washington Medical Center
state: Washington
Study officials:
affiliation: University of Washington
name: Michael R Bailey, PhD, MS
role: PRINCIPAL_INVESTIGATOR
References:
citation: May PC, Kreider W, Maxwell AD, Wang YN, Cunitz BW, Blomgren PM, Johnson CD, Park JSH, Bailey MR, Lee D, Harper JD, Sorensen MD. Detection and Evaluation of Renal Injury in Burst Wave Lithotripsy Using Ultrasound and Magnetic Resonance Imaging. J Endourol. 2017 Aug;31(8):786-792. doi: 10.1089/end.2017.0202. Epub 2017 Jun 16.
citation: Maxwell AD, Cunitz BW, Kreider W, Sapozhnikov OA, Hsi RS, Harper JD, Bailey MR, Sorensen MD. Fragmentation of urinary calculi in vitro by burst wave lithotripsy. J Urol. 2015 Jan;193(1):338-44. doi: 10.1016/j.juro.2014.08.009. Epub 2014 Aug 9.
citation: Bailey MR, Maxwell AD, Cao S, Ramesh S, Liu Z, Williams JC, Thiel J, Dunmire B, Colonius T, Kuznetsova E, Kreider W, Sorensen MD, Lingeman JE, Sapozhnikov OA. Improving Burst Wave Lithotripsy Effectiveness for Small Stones and Fragments by Increasing Frequency: Theoretical Modeling and Ex Vivo Study. J Endourol. 2022 Jul;36(7):996-1003. doi: 10.1089/end.2021.0714. Epub 2022 Jun 22.
citation: Harper JD, Metzler I, Hall MK, Chen TT, Maxwell AD, Cunitz BW, Dunmire B, Thiel J, Williams JC, Bailey MR, Sorensen MD. First In-Human Burst Wave Lithotripsy for Kidney Stone Comminution: Initial Two Case Studies. J Endourol. 2021 Apr;35(4):506-511. doi: 10.1089/end.2020.0725. Epub 2020 Nov 5.