Active, not recruitingNCT02028559Updated Jun 1, 2026Results posted

Safety and Effectiveness of the Ultrasonic Propulsion of Kidney Stones

An interventional study of Propulse 1 with C5-2 probe and Propulse 1 with SC-X probe in Kidney Stones, Nephrolithiasis and Urolithiasis, sponsored by University of Washington. Active, not recruiting at 2 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-06-01.

Sponsored by University of Washington · Not applicable, Interventional, and Basic science

Phase: Not applicable
Study type: Interventional
Enrollment: 172
Allocation: Non-randomized
Ages: 18 Years and older
Sex: All

Study summary

This study tests moving kidney stones using focused ultrasound (referred to as ultrasonic propulsion). The study includes multiple population groups to investigate the ability of our technology to: a) move stone fragments to a location within the kidney to improve their chances of passage, and thus reduce the occurrence of additional symptomatic events and retreatment or b) move a symptomatic stone to relieve symptoms and pain.

Read the detailed description

This is an investigator initiated, NIH-funded study conducted by the University of Washington (UW). Our research group has developed a new, non-invasive technology using low intensity focused ultrasound to reposition kidney stones by imparting sufficient acoustic energy to physically move a stone. The focused ultrasound pulses are similar to pulses that may be used in elastography or acoustic radiation force imaging. Like conventional ultrasound, the probe is placed in contact with the patient's skin to image the stone following standard ultrasound imaging procedure. The same probe is then used to focus the ultrasound and apply a burst (a sequence of pulses) of acoustic force to push the stone. Brightness mode (B-mode) imaging is interleaved with the "pushing" pulses (Push-mode) to monitor stone movement. The user controls the burst amplitude. To limit heating at the probe surface, there is a slight delay before the operator can execute the next push.

In addition to undergoing the investigational procedure, the research activities include the following:

subjects undergo a pain questionnaire before and after the procedure and report their current level of stone pain on a scale of 0 (no pain) to 10 (worst possible pain);
the subject's skin in the area of probe placement is observed before and after the procedure;
subjects are contacted once-a-week for 3 weeks to evaluate for potential adverse events, pain medication use, and, if applicable, stone passage;
subjects are requested to undergo at least one follow-up imaging 4 - 12 weeks post-procedure;
a review of each subject's medical records is conducted 90-days post-procedure to evaluate for additional effectiveness and safety events.
Specifically for the residual fragment population (randomized control trial), subjects are contacted every 6 months for 3 years and their electronic medical record is reviewed for 5 years for stone growth, symptomatic, unscheduled medical visits, and surgery related to stones.

Subjects that qualify for the trial are recruited into different study arms (referred to as Population groups) based on their type of stone condition (de novo stone versus post-lithotripsy fragment), size of stone (≤ 5 mm or > 5 mm), and management plan (clinical observation or surgical intervention). The objectives vary based upon the Population group. Subjects may qualify for more than one population group and may undergo the investigational procedure up to 4 times total (inclusive of both the left and right-side urinary tracts). Subjects can only be enrolled in one population group at a time, there is a separate consent for each study population, and each study population is considered independent of the other groups. Recruitment into all population groups has been completed.

First-in-Human Population: This was the initial group of subjects included under this clinical trial. This was a 15-subject feasibility study that included a broad range of populations. This feasibility population formulated the basis for expanding the trial into a larger study addressing each population separately. This is encompassed in subject populations 2-5 below.
De Novo Small Stone Population: Subjects undergo the investigational procedure awake and in the clinic. To qualify the subject must have a de novo stone ≤ 5 mm in largest dimension. Ultrasonic propulsion is used with the intent to help facilitate stone passage. If the stone is larger than 5 mm, subjects could be recruited into the URS subject population (see bullet point #3 below).
Concurrent with URS Population: Subjects undergo the investigational procedure while anesthetized and concurrently undergoing a ureteroscopy guided laser lithotripsy procedure (referred to herein as URS). To qualify the subject must have at least one stone ≤ 20 mm in the largest dimension and be scheduled for surgery. Ultrasonic propulsion may be used to move a de novo stone or stone fragments of varying sizes generated over the course of the URS procedure. Note that since these subjects are anesthetized, a pain questionnaire is not included as part of their protocol.
Obstructing Stone Population: Subjects undergo the investigational procedure awake and in the clinic or emergency department (ED) setting. To qualify the subject must have clinical imaging confirmation of an obstructing stone with their pain managed and complete a urinalysis to for assess infection risk. Ultrasonic propulsion is used with the intent to relieve the obstruction and associated pain. A subset of subjects were exposed to higher amplitude dislodging pulses, in addition to the ultrasonic propulsion pulses.
Residual Fragment Population: Subjects undergo the investigational procedure awake and in the clinic setting. To qualify the subject must have at least one post-lithotripsy residual fragment (≤ 5 mm in largest dimension) identified either on imaging or based on the investigator's interpretation of that imaging. This is a prospective, open-label, multicenter, randomized control trial (RCT) with a treatment arm and control arm. The only difference in protocol between the two arms is that only the treatment group undergoes the investigational procedure and the associated post-procedure pain questionnaire and the post-procedure skin surface inspection. Ultrasonic propulsion is used with the intent to demonstrate: a) the ability of the ultrasonic propulsion device to reposition stones within the human kidney, b) the subsequent clinical benefit of facilitating stone passage and reducing stone burden, and c) the subsequent clinical benefit of reducing relapse. This is the only population group recruited across more than one site - the UW and the VA Puget Sound Healthcare System.

Conditions studied

Kidney Stones
Nephrolithiasis
Urolithiasis

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Keywords

stones
kidney
stone fragments
lithotripsy

In context

Kidney Calculi

509 studies on the registry are indexed under Kidney Calculi; 146 are open to participants now.

This study's enrollment of 172 is above the median of 86 across 391 interventional studies indexed under Kidney Calculi.

Browse Kidney Calculi studies →

Lead sponsor

University of Washington is the lead sponsor of 1,433 studies on the registry; 225 are open to participants now.

Of its 158 completed or terminated interventional studies of FDA-regulated products, 136 (86%) have results posted.

Browse University of Washington studies →

Counted across the registry records on this site, refreshed daily.

Who can participate

Ages eligible: 18 Years and older
Sexes eligible: All
Accepts healthy volunteers: No

Eligibility criteria

Inclusion Criteria:

Individuals suspected of having at least one kidney stone. This includes:
- Patients who are being managed with watchful waiting or medical therapy
- Patients who recently (but > 4 weeks) underwent lithotripsy treatment of their stones
- Patients scheduled for lithotripsy treatment

Individuals suspected of having an obstructed stone. This includes:
- Patients presenting with renal colic
- Patients presenting with hydronephrosis or dilation of the ureter

Primary Exclusion Criteria for all groups:

Individuals under 18 years of age
Individuals with non-echogenic stones
Individuals unable or unwilling to comply with the follow-up requirements
Individuals with a coagulation abnormality or taking blood thinners or other anticoagulant at levels
Individuals with mobility issues who are unable to comfortably lie for up to 30 minutes or roll from their back to their side
Individuals belonging to a vulnerable group (pregnant, mentally disabled, physically disabled, prisoner, etc.)
Individuals who have already received four previous ultrasonic propulsion procedures.
Individuals who have received an ultrasonic propulsion treatment within the last 4 weeks.

Additional Exclusion Criteria for Obstructing Stone population

Individuals with a suspicion of kidney infection or exhibiting signs of sepsis
Individuals whom the treating physician considers to be at high risk for serious alternate diagnoses such as acute infectious etiologies (e.g. cholecystitis, appendicitis), aortic aneurysm and rupture, or bowel disorders.
Individuals who have undergone renal transplant, or individuals who will undergo dialysis.
Individuals with bilateral hydronephrosis
Individuals with a single kidney
Individuals who have already received an ultrasonic propulsion investigative treatment for the same obstructing stone

Terms in these criteria, in plain language(1)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Clinically significant: Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.

Study design

Phase: Not applicable
Primary purpose: Basic science
Allocation: Non-randomized
Intervention model: Single group
Masking: Single (Outcomes assessor)
Enrollment: 172 participants (actual)

Study arms

Experimental
First in Human (FIH)
Initial phase of the trial. Includes a broad spectrum of population groups (e.g. de novo, concurrent with URS, residual fragments) to demonstrate feasibility. Intervention consists of the non-invasive application of ultrasound to move stones within the kidney and ureter. Procedure conducted with the Propulse 1 device and C5-2 transducer. Subjects (n = 15) receive up to 40 push bursts.
Device: Propulse 1 with C5-2 probe
Experimental
De Novo Small Stone
Segment of the trial focused specifically on subjects with small (≤ 5 mm) stones under observation management. Intervention consists of the non-invasive application of ultrasound to move stones within the kidney and ureter with the goal to facilitate passage. Procedure is conducted with the Propulse 1 device and SC-X transducer. Subjects (n = 2) receive multiple Push bursts up to a maximum cumulative dose exposure of 5 minutes. Each burst is a maximum of 3 seconds in duration and 200 W/cm2 in intensity.
Device: Propulse 1 with SC-X probe
Experimental
Concurrent with URS
Segment of the trial focused specifically on subjects undergoing ultrasonic propulsion concurrently with their ureteroscopy guided laser lithotripsy procedure. Study provides visual observation of stone motion and any potential tissue injury. Intervention consists of the non-invasive application of ultrasound to move stones within the kidney and ureter. Procedure is conducted with the Propulse 1 device and SC-X transducer. Subjects (n = 18) receive multiple Push bursts up to a maximum cumulative dose exposure of 5 minutes. Each burst is a maximum of 3 seconds in duration and 200 W/cm2 in intensity.
Device: Propulse 1 with SC-X probe
Experimental
Obstructing Stone - Pushing only
Segment of the trial focused specifically on subjects reporting to clinic or the emergency department with an obstructing stone. Intervention consists of the non-invasive application of ultrasound to relieve pain and facilitate passage. Procedure is conducted with the Propulse 1 device and SC-X transducer. Subjects (n = 16) receive multiple Push bursts up to a maximum cumulative dose exposure of 5 minutes. Each burst is a maximum of 3 seconds in duration and 200 W/cm2 in intensity.
Device: Propulse 1 with SC-X probe
Experimental
Residual Fragment (Treatment group)
Segment of the trial focused specifically on subjects with small (≤ 5 mm) residual fragments following lithotripsy. This is the Treatment arm of a randomized control trial. Intervention consists of the non-invasive application of ultrasound to move stones within the kidney and ureter with the goal to facilitate passage. Procedure is conducted with the Propulse 1 device and SC-X transducer. Subjects (n = 54) receive multiple Push bursts up to a maximum cumulative dose exposure of 5 minutes. Each burst is a maximum of 3 seconds in duration and 200 W/cm2 in intensity.
Device: Propulse 1 with SC-X probe
No intervention
Residual Fragment (Control group)
Segment of the trial focused specifically on subjects with small (≤ 5 mm) residual fragments following lithotripsy. This is the Control arm of a randomized control trial. Subjects (n = 54) follow same protocol as Residual Fragment (Treatment group) but do not receive the ultrasonic propulsion intervention.
Experimental
Obstructing Stone - Pushing + Dislodging
Segment of the trial focused specifically on subjects reporting to clinic or the emergency department with an obstructing stone. Participants were separate from the Obstructing Stone - Pushing only based on a stone skin-to-stone distance \< 8 mm. Intervention consists of the non-invasive application of ultrasound to relieve pain and facilitate passage. Procedure is conducted with the Propulse 1 device and SC-X transducer. Subjects (n = 13) receive both Dislodging and Push bursts up to a maximum cumulative dose exposure of 5 minutes. This is the only population to receive the Dislodging bursts, which consist of higher amplitude (up to 7 MPa) and shorter duration pulses compared to pushing. The Push burst is a maximum of 3 seconds in duration and 200 W/cm2 in intensity.
Device: Propulse 1 with SC-X probe

Interventions

DevicePropulse 1 with C5-2 probe
Move kidney stones with Propulse 1 device.
DevicePropulse 1 with SC-X probe
Move kidney stones with Propulse 1 device.

What researchers measure

Primary outcomes

Measurement of Stone Motion Caused by Ultrasound
Percentage of study participants for which stone motion was observed on the real-time ultrasound images.
Time frame: At the time of the procedure. To be evaluated with each therapy pulse over an approximately 1-hour study. Confirmed with post-procedure review of the study video.
Measurement of Stone Passage
The percentage of participants reporting visual observation of stone passage or confirmed with follow-up imaging. For the residual fragment RCT population specifically, the percentage of participants reporting visual observation of stone passage during the 3-week follow-up period after the procedure or randomization (Control group).
Time frame: Measurement occurs over 3 weeks (weekly phone call or email encounter with the subject) plus review of the subject's medical chart up to the point the subject is exited from the study.
Measurement of Relapse
The percentage of participants experiencing stone relapse defined as: an unscheduled, symptomatic visit for stones on the study side, surgery for stones on the study side, or stone growth of a residual fragment measured by clinical imaging exams. This measurement is specific to the residual fragment population and associated randomized control trial. Only a single relapse event is counted per participant, though a participant could experience more than one event.
Time frame: Measurement up to 5 years post-procedure. This includes a phone call or email exchange semi-annually for up to 3-years and a medical record review (including imaging) semi-annually for up to 5-years.

Other outcomes

Number of Participants With Discomfort Related to the Device or Procedure
Pre-Procedure: The participant will be asked directly what discomfort, on a scale of 0 (no pain) to 10 (worst pain possible), they are experiencing and to point to where the discomfort/pain is located. This is the participant's recorded baseline measure. During Procedure: The participant will be asked directly if they are experiencing any new or different discomfort, on a scale of 0 (no pain) to 10 (worst pain possible), and to point to where the discomfort/pain is located. Any new or different discomfort above baseline will be assumed related to the device or procedure; there is no minimum threshold for reporting. Post Procedure: The participant will be asked directly what discomfort, on a scale of 0 (no pain) to 10 (worst pain possible), they are experiencing and to point to where the discomfort/pain is located. Any new or different discomfort above baseline will be assumed related to the device or procedure; there is no minimum threshold for reporting.
Time frame: At the time of the procedure. To be evaluated over an approximately 1 hour study.

Results

Posted Jun 1, 2026

Participant flow

Participants were recruited based on physician referral and identification of potential qualifying individuals through review of the clinic patient list. Participants were recruited between December of 2013 and July of 2024. The first participant was enrolled on December 17, 2013 and the last participant was enrolled on July 23, 2024.

Participant flow — Overall Study
Milestone	First in Human (FIH)	De Novo Small Stone	Concurrent With URS	Obstructing Stone - Pushing Only	Obstructing Stone - Dislodging + Pushing	Residual Fragment (Treatment Group)	Residual Fragment (Control Group)
Started	15	2	18	16	13	54	54
Per protocol population	15	2	18	16	13	49	53
Completed	15	2	18	10	8	44	39
Not completed	0	0	0	6	5	10	15
Withdrew: Lost to follow-up	0	0	0	1	0	0	1
Withdrew: Death	0	0	0	0	0	1	3
Withdrew: Protocol violation	0	0	0	0	0	2	0
Withdrew: Underwent standard-of-care surgery	0	0	0	5	5	7	11

Outcome measures

PrimaryMeasurement of Stone Motion Caused by Ultrasound

Percentage of study participants for which stone motion was observed on the real-time ultrasound images.

Time frame:: At the time of the procedure. To be evaluated with each therapy pulse over an approximately 1-hour study. Confirmed with post-procedure review of the study video.
Reported as:: Count of participants · Participants

Measurement of Stone Motion Caused by Ultrasound
Participants	First in Human (FIH)	De Novo Small Stone	Concurrent With URS	Obstructing Stone - Pushing Only	Obstructing Stone - Dislodging + Pushing	Residual Fragment (Treatment Group)	Residual Fragment (Control Group)
Measurement of Stone Motion Caused by Ultrasound	14	1	15	11	8	41	0

PrimaryMeasurement of Stone Passage

The percentage of participants reporting visual observation of stone passage or confirmed with follow-up imaging. For the residual fragment RCT population specifically, the percentage of participants reporting visual observation of stone passage during the 3-week follow-up period after the procedure or randomization (Control group).

Time frame:: Measurement occurs over 3 weeks (weekly phone call or email encounter with the subject) plus review of the subject's medical chart up to the point the subject is exited from the study.
Reported as:: Count of participants · Participants

Measurement of Stone Passage
Participants	First in Human (FIH)	De Novo Small Stone	Concurrent With URS	Obstructing Stone - Pushing Only	Obstructing Stone - Dislodging + Pushing	Residual Fragment (Treatment Group)	Residual Fragment (Control Group)
Measurement of Stone Passage	4	0	—	11	7	35	4

PrimaryMeasurement of Relapse

The percentage of participants experiencing stone relapse defined as: an unscheduled, symptomatic visit for stones on the study side, surgery for stones on the study side, or stone growth of a residual fragment measured by clinical imaging exams. This measurement is specific to the residual fragment population and associated randomized control trial. Only a single relapse event is counted per participant, though a participant could experience more than one event.

Time frame:: Measurement up to 5 years post-procedure. This includes a phone call or email exchange semi-annually for up to 3-years and a medical record review (including imaging) semi-annually for up to 5-years.
Reported as:: Count of participants · Participants

Measurement of Relapse
Participants	First in Human (FIH)	De Novo Small Stone	Concurrent With URS	Obstructing Stone - Pushing Only	Obstructing Stone - Dislodging + Pushing	Residual Fragment (Treatment Group)	Residual Fragment (Control Group)
Measurement of Relapse	—	—	—	—	—	8	27

Other pre-specifiedNumber of Participants With Discomfort Related to the Device or Procedure

Pre-Procedure: The participant will be asked directly what discomfort, on a scale of 0 (no pain) to 10 (worst pain possible), they are experiencing and to point to where the discomfort/pain is located. This is the participant's recorded baseline measure. During Procedure: The participant will be asked directly if they are experiencing any new or different discomfort, on a scale of 0 (no pain) to 10 (worst pain possible), and to point to where the discomfort/pain is located. Any new or different discomfort above baseline will be assumed related to the device or procedure; there is no minimum threshold for reporting. Post Procedure: The participant will be asked directly what discomfort, on a scale of 0 (no pain) to 10 (worst pain possible), they are experiencing and to point to where the discomfort/pain is located. Any new or different discomfort above baseline will be assumed related to the device or procedure; there is no minimum threshold for reporting.

Time frame:: At the time of the procedure. To be evaluated over an approximately 1 hour study.
Reported as:: Count of participants · Participants

Number of Participants With Discomfort Related to the Device or Procedure
Participants	First in Human (FIH)	De Novo Small Stone	Concurrent With URS	Obstructing Stone - Pushing Only	Obstructing Stone - Dislodging + Pushing	Residual Fragment (Treatment Group)	Residual Fragment (Control Group)
Number of Participants With Discomfort Related to the Device or Procedure	2	0	—	2	3	15	—

Adverse events

Collected over AE data were collected through contact with participants once per week for 3 weeks post-procedure or randomization (Control group). Medical charts were also reviewed out to 90 days post-procedure or randomization for any additional AEs not captured during the 3-week follow-up. The residual fragment population was additionally followed up to 5 years post-procedure or randomization. AEs were not collected, but participant deaths were recorded.. Non-serious events are listed at a 0% frequency threshold.

Adverse event summary by group
Group	Deaths	Serious	Other
First in Human (FIH)	0/15 (0%)	0/15 (0%)	3/15 (20%)
De Novo Small Stone	0/2 (0%)	0/2 (0%)	0/2 (0%)
Concurrent With URS	0/18 (0%)	1/18 (5.6%)	2/18 (11.1%)
Obstructing Stone - Pushing Only	0/16 (0%)	1/16 (6.3%)	1/16 (6.3%)
Obstructing Stone - Dislodging + Pushing	0/13 (0%)	0/13 (0%)	6/13 (46.2%)
Residual Fragment (Treatment Group)	1/54 (1.9%)	0/54 (0%)	31/54 (57.4%)
Residual Fragment (Control Group)	3/54 (5.6%)	0/54 (0%)	20/54 (37%)

Most frequent serious events

Most frequent serious events
Event	First in Human (FIH)	De Novo Small Stone	Concurrent With URS	Obstructing Stone - Pushing Only	Obstructing Stone - Dislodging + Pushing	Residual Fragment (Treatment Group)	Residual Fragment (Control Group)
Atrial FibrillationCardiac disorders	0/15	0/2	1/18	1/16	—	0/54	0/54

Most frequent other events

Showing 10 of 11

Most frequent other events
Event	First in Human (FIH)	De Novo Small Stone	Concurrent With URS	Obstructing Stone - Pushing Only	Obstructing Stone - Dislodging + Pushing	Residual Fragment (Treatment Group)	Residual Fragment (Control Group)
HematuriaRenal and urinary disorders	0/15	0/2	—	1/16	6/13	4/54	3/54
PainNervous system disorders	2/15	0/2	—	1/16	0/13	21/54	17/54
Skin EffectsSkin and subcutaneous tissue disorders	1/15	0/2	2/18	0/16	0/13	3/54	0/54
Change in Urinary FrequencyRenal and urinary disorders	0/15	0/2	—	0/16	0/13	6/54	3/54
Change in Urinary UrgencyRenal and urinary disorders	0/15	0/2	—	0/16	0/13	5/54	0/54
DiarrheaGastrointestinal disorders	0/15	0/2	0/18	0/16	0/13	5/54	2/54
DysuriaRenal and urinary disorders	0/15	0/2	—	0/16	0/13	4/54	2/54
NauseaGastrointestinal disorders	0/15	0/2	—	0/16	0/13	3/54	3/54
ConstipationGastrointestinal disorders	0/15	0/2	0/18	0/16	0/13	3/54	0/54
EmesisGastrointestinal disorders	0/15	0/2	—	0/16	0/13	0/54	2/54

Baseline characteristics

Age, Continuous
Age, Continuous(years)	First in Human (FIH)	De Novo Small Stone	Concurrent With URS	Obstructing Stone - Pushing Only	Obstructing Stone - Dislodging + Pushing	Residual Fragment (Treatment Group)	Residual Fragment (Control Group)	Total
Mean	56 ± 11	70 ± 0	58 ± 15	51 ± 19	40 ± 16	60 ± 16	60 ± 12	58 ± 15

Sex: Female, Male
Sex: Female, Male(Participants)	First in Human (FIH)	De Novo Small Stone	Concurrent With URS	Obstructing Stone - Pushing Only	Obstructing Stone - Dislodging + Pushing	Residual Fragment (Treatment Group)	Residual Fragment (Control Group)	Total
Ultrasonic Propulsion — Female	4	0	6	5	4	17	21	57
Ultrasonic Propulsion — Male	11	2	12	11	9	37	33	115

Ethnicity (NIH/OMB)
Ethnicity (NIH/OMB)(Participants)	First in Human (FIH)	De Novo Small Stone	Concurrent With URS	Obstructing Stone - Pushing Only	Obstructing Stone - Dislodging + Pushing	Residual Fragment (Treatment Group)	Residual Fragment (Control Group)	Total
Hispanic or Latino	0	0	0	2	2	5	5	14
Not Hispanic or Latino	15	2	18	14	11	49	49	158
Unknown or Not Reported	0	0	0	0	0	0	0	0

Race (NIH/OMB)
Race (NIH/OMB)(Participants)	First in Human (FIH)	De Novo Small Stone	Concurrent With URS	Obstructing Stone - Pushing Only	Obstructing Stone - Dislodging + Pushing	Residual Fragment (Treatment Group)	Residual Fragment (Control Group)	Total
American Indian or Alaska Native	1	0	0	0	1	0	0	2
Asian	3	0	1	1	2	0	6	13
Native Hawaiian or Other Pacific Islander	0	0	0	0	0	1	0	1
Black or African American	0	0	0	1	1	2	2	6
White	11	2	17	14	9	48	43	144
More than one race	0	0	0	0	0	2	1	3
Unknown or Not Reported	0	0	0	0	0	1	2	3

Region of Enrollment
Region of Enrollment(participants)	First in Human (FIH)	De Novo Small Stone	Concurrent With URS	Obstructing Stone - Pushing Only	Obstructing Stone - Dislodging + Pushing	Residual Fragment (Treatment Group)	Residual Fragment (Control Group)	Total
United States	15	2	18	16	13	54	54	172

Body-Mass Index (BMI)
Body-Mass Index (BMI)(kg/m^2)	First in Human (FIH)	De Novo Small Stone	Concurrent With URS	Obstructing Stone - Pushing Only	Obstructing Stone - Dislodging + Pushing	Residual Fragment (Treatment Group)	Residual Fragment (Control Group)	Total
Mean	29.4 ± 2.9	29 ± 0	27.6 ± 5.0	25.3 ± 4.2	24.7 ± 4.5	27.9 ± 5.2	28.8 ± 6.6	27.8 ± 5.5

Renal Side
Renal Side(Participants)	First in Human (FIH)	De Novo Small Stone	Concurrent With URS	Obstructing Stone - Pushing Only	Obstructing Stone - Dislodging + Pushing	Residual Fragment (Treatment Group)	Residual Fragment (Control Group)	Total
Left	6	1	9	9	8	41	32	106
Right	10	1	10	7	5	13	22	68

Target (Stone) Location
Target (Stone) Location(Number of Targets (Stone))	First in Human (FIH)	De Novo Small Stone	Concurrent With URS	Obstructing Stone - Pushing Only	Obstructing Stone - Dislodging + Pushing	Residual Fragment (Treatment Group)	Residual Fragment (Control Group)	Total
Lower pole	24	4	20	0	0	58	54	160
Mid pole	11	1	28	0	0	18	20	78
Upper pole	4	0	14	0	0	1	7	26
Renal Pelvis / UPJ	4	0	0	3	0	0	0	7
Distal Ureter / UVJ	0	0	0	13	13	0	0	26

Study locations

2 sites

VA Puget Sound Health Care System
Seattle, Washington 98108, United States
37 other open studies at this site →
University of Washington Department of Urology
Seattle, Washington 98195, United States
261 other open studies at this site →

References and documents

Publications

Hall MK, Thiel J, Dunmire B, Samson PC, Kessler R, Sunaryo P, Sweet RM, Metzler IS, Chang HC, Gunn M, Dighe M, Anderson L, Popchoi C, Managuli R, Cunitz BW, Burke BH, Ding L, Gutierrez B, Liu Z, Sorensen MD, Wessells H, Bailey MR, Harper JD. First Series Using Ultrasonic Propulsion and Burst Wave Lithotripsy to Treat Ureteral Stones. J Urol. 2022 Nov;208(5):1075-1082. doi: 10.1097/JU.0000000000002864. Epub 2022 Nov 1. PubMed 36205340 ↗
Dai JC, Sorensen MD, Chang HC, Samson PC, Dunmire B, Cunitz BW, Thiel J, Liu Z, Bailey MR, Harper JD. Quantitative Assessment of Effectiveness of Ultrasonic Propulsion of Kidney Stones. J Endourol. 2019 Oct;33(10):850-857. doi: 10.1089/end.2019.0340. Epub 2019 Sep 25. PubMed 31333058 ↗
Harper JD, Cunitz BW, Dunmire B, Lee FC, Sorensen MD, Hsi RS, Thiel J, Wessells H, Lingeman JE, Bailey MR. First in Human Clinical Trial of Ultrasonic Propulsion of Kidney Stones. J Urol. 2016 Apr;195(4 Pt 1):956-64. doi: 10.1016/j.juro.2015.10.131. Epub 2015 Oct 30. PubMed 26521719 ↗
Sorensen MD, Dunmire B, Thiel J, Cunitz BW, Burke BH, Levchak BJ, Popchoi C, Holmes AE, Kucewicz JC, Hall MK, Dighe M, Dai JC, Cormack FC, Liu Z, Bailey MR, Porter MP, Harper JD. Randomized Controlled Trial of Ultrasonic Propulsion-Facilitated Clearance of Residual Kidney Stone Fragments vs Observation. J Urol. 2024 Dec;212(6):811-820. doi: 10.1097/JU.0000000000004186. Epub 2024 Aug 15. PubMed 39146526 ↗
Yang CC, Keating EE, Managuli R, Honssinger N, Holt SK, Desai AC. A Randomized Controlled Trial of Ultrasonic Propulsion-Facilitated Clearance of Residual Renal Stone Fragments vs Observation. J Urol. 2025 Jul;214(1):3-9. doi: 10.1097/JU.0000000000004501. Epub 2025 Mar 3. PubMed 40030414 ↗
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. PubMed 32940089 ↗

Study documents

Study protocol ↗ · Mar 30, 2022

PDFs hosted by the registry, ClinicalTrials.gov.

Individual participant data

Plan to share: No

Updates

Tracking since Sep 25, 2026

No changes since tracking began. The registry record was last updated on Jun 1, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗

Registry details

Key details

Study ID: NCT02028559
Lead sponsor: University of Washington
Collaborators: VA Puget Sound Health Care System
Responsible party: Jonathan Harper, MD (Assistant Professor, Urology, University of Washington) — Principal investigator
First posted: Jan 7, 2014
Start date: Dec 17, 2013
Primary completion: Aug 1, 2025
Completion: May 31, 2026 (estimated)
Results posted: Jun 1, 2026
Last update: Jun 1, 2026

Study contacts

Jonathan Harper, MD

principal investigator · University of Washington

Oversight

Data monitoring committee: Yes

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This study is active, not recruiting, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.

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