An interventional study of Ultrasound in Stone, Kidney and Ultrasound Therapy; Complications, sponsored by University of California, San Francisco. Terminated at 1 site in United States. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-10-01.
Sponsored by University of California, San Francisco · Not applicable, Interventional, and Diagnostic
The purpose of this study is to assess the accuracy of ultrasound and traditional fluoroscopy to find the residual fragments before retrograde intrarenal surgery is complete. This would ultimately limit the need for radiation exposure and improve the quality of clinical care given to patients and healthcare teams.
Ultrasound is currently gaining popularity as an alternative imaging modality for the diagnosis and treatment of urolithiasis. However, the benefit of ultrasound on the diagnostic accuracy of detecting residual fragments during retrograde intrarenal surgery (RIRS) has never been evaluated in a randomized study. Its use would reduce radiation exposure for patients and care team members as well as improve stone free clearance rates for surgery. Therefore, The investigators plan to conduct a randomized trial to assess the diagnostic accuracy of ultrasound and fluoroscopy in conjunction with endoscopic examination for detecting residual stone fragments during retrograde intrarenal surgery. After admission, approximately 172 subjects will be randomized in a 1:1 ratio to receive ultrasound or fluoroscopy before completing RIRS. Subsequently, four weeks after the operation, the investigators will compare with routine low-dose non-contrast computed tomography as a gold standard for detecting residual fragments. If ultrasound is more accurate than fluoroscopy in detecting residual fragments, the investigators will encourage this approach as it can reduce radiation exposure for patients and healthcare professionals.
598 studies on the registry are indexed under Kidney Calculi; 163 are open to participants now.
This study's enrollment of 47 is below the median of 90 across 461 interventional studies indexed under Kidney Calculi.
Browse Kidney Calculi studies →University of California, San Francisco is the lead sponsor of 2,132 studies on the registry; 375 are open to participants now.
Of its 262 completed or terminated interventional studies of FDA-regulated products, 196 (75%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Before completing retrograde intrarenal surgery, a complete endoscopic examination will be performed along with ultrasound by the same endourologist to determine the size of the largest residual fragment.
Diagnostic Test: Ultrasound
Standard of care, control Before completing retrograde intrarenal surgery, a complete endoscopic examination will be performed along with fluoroscopy by the same endourologist to determine the size of the largest residual fragment.
Before completing retrograde intrarenal surgery, a complete endoscopic examination will be performed along with ultrasound instead of fluoroscopy by the same endourologist to determine the size of the largest residual fragment.
Number of Participants With Diagnostic Accuracy Detecting Residual Fragments During Retrograde Intrarenal Surgery
Number of participants with diagnostic accuracy detecting residual fragments during retrograde intrarenal surgery. The fragments are confirmed via post operative imagery and the number of participants with residual is reported.
Time frame: 4 weeks
Number of Participants With Sensitivity Detecting Residual Fragments During Retrograde Intrarenal Surgery
Number of participants with sensitivity detecting residual fragments during retrograde intrarenal surgery. The clinician would visually confirm the fragments during the procedure and this was compared to the post-operative imagery. The number of participants with the same results on the visual confirmation and the post-operative imagery is reported.
Time frame: 4 weeks
Number of Participants With Positive Predictive Value Detecting Residual Fragments During Retrograde Intrarenal Surgery
Number of participants with positive predictive value detecting residual fragments during retrograde intrarenal surgery. The clinician would visually confirm the fragments during the procedure and this was compared to the post-operative imagery. The number of participants with the same results on the visual confirmation and the post-operative imagery is reported.
Time frame: 4 weeks
Number of Participants With Negative Predictive Value Detecting Residual Fragments During Retrograde Intrarenal Surgery
Number of participants with negative predictive value detecting residual fragments during retrograde intrarenal surgery. The clinician would visually confirm the fragments during the procedure and this was compared to the post-operative imagery. The number of participants with the same results on the visual confirmation and the post-operative imagery is reported.
Time frame: 4 weeks
Number of Participants With Reported Operative Time in Minutes
This is the number of participants that had operative time in minutes collected.
Time frame: 4 weeks
Number of Participants With Data Indicating Surgical Complications Graded I to V on the Modified Clavien-Dindo Classification
Number of Participants with data collected and indicating surgical complications graded I to V on the modified Clavien-Dindo classification.
Time frame: 4 weeks
Number of Participants With Specificity Detecting Residual Fragments During Retrograde Intrarenal Surgery
Number of participants with specificity detecting residual fragments during retrograde intrarenal surgery. The clinician would visually confirm the fragments during the procedure and this was compared to the post-operative imagery. The number of participants with the same results on the visual confirmation and the post-operative imagery is reported.
Time frame: 4 weeks
We identifed subjects from both the urology clinic AND the Emergency Department visit. When patients presented and the urology inpatient consult service is consulted, that triggered the team to screen patients for possible study recruitment. Patients that required stone removal surgery and that opted for retrograde intrarenal surgery were presented with this study. Eligibility was determined based on the patient's presentation and medical chart review.
| Milestone | Ultrasound | Fluoroscopy |
|---|---|---|
| Started | 21 | 26 |
| Completed | 19 | 23 |
| Not completed | 2 | 3 |
| Withdrew: Lost to follow-up | 2 | 3 |
Number of participants with diagnostic accuracy detecting residual fragments during retrograde intrarenal surgery. The fragments are confirmed via post operative imagery and the number of participants with residual is reported.
| Participants | Ultrasound | Fluoroscopy |
|---|---|---|
| Number of Participants With Diagnostic Accuracy Detecting Residual Fragments During Retrograde Intrarenal Surgery | 9 | 13 |
Number of participants with sensitivity detecting residual fragments during retrograde intrarenal surgery. The clinician would visually confirm the fragments during the procedure and this was compared to the post-operative imagery. The number of participants with the same results on the visual confirmation and the post-operative imagery is reported.
| Participants | Ultrasound | Fluoroscopy |
|---|---|---|
| Number of Participants With Sensitivity Detecting Residual Fragments During Retrograde Intrarenal Surgery | 19 | 23 |
Number of participants with positive predictive value detecting residual fragments during retrograde intrarenal surgery. The clinician would visually confirm the fragments during the procedure and this was compared to the post-operative imagery. The number of participants with the same results on the visual confirmation and the post-operative imagery is reported.
| Participants | Ultrasound | Fluoroscopy |
|---|---|---|
| Number of Participants With Positive Predictive Value Detecting Residual Fragments During Retrograde Intrarenal Surgery | 9 | 13 |
Number of participants with negative predictive value detecting residual fragments during retrograde intrarenal surgery. The clinician would visually confirm the fragments during the procedure and this was compared to the post-operative imagery. The number of participants with the same results on the visual confirmation and the post-operative imagery is reported.
| Participants | Ultrasound | Fluoroscopy |
|---|---|---|
| Number of Participants With Negative Predictive Value Detecting Residual Fragments During Retrograde Intrarenal Surgery | 10 | 10 |
This is the number of participants that had operative time in minutes collected.
| Participants | Ultrasound | Fluoroscopy |
|---|---|---|
| Number of Participants With Reported Operative Time in Minutes | 19 | 23 |
Number of Participants with data collected and indicating surgical complications graded I to V on the modified Clavien-Dindo classification.
| Participants | Ultrasound | Fluoroscopy |
|---|---|---|
| Number of Participants With Data Indicating Surgical Complications Graded I to V on the Modified Clavien-Dindo Classification | 0 | 0 |
Number of participants with specificity detecting residual fragments during retrograde intrarenal surgery. The clinician would visually confirm the fragments during the procedure and this was compared to the post-operative imagery. The number of participants with the same results on the visual confirmation and the post-operative imagery is reported.
| Participants | Ultrasound | Fluoroscopy |
|---|---|---|
| Number of Participants With Specificity Detecting Residual Fragments During Retrograde Intrarenal Surgery | 9 | 13 |
Collected over 4 weeks. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Ultrasound | 0/21 (0%) | 0/21 (0%) | 0/21 (0%) |
| Fluoroscopy | 0/26 (0%) | 0/26 (0%) | 0/26 (0%) |
It is the same as the assignment in Participant Flow or information about how participants contribute units.
| Age, Categorical(Participants) | Ultrasound | Fluoroscopy | Total |
|---|---|---|---|
| <=18 years | 0 | 0 | 0 |
| Between 18 and 65 years | 11 | 19 | 30 |
| >=65 years | 10 | 7 | 17 |
| Sex: Female, Male(Participants) | Ultrasound | Fluoroscopy | Total |
|---|---|---|---|
| Female | 10 | 13 | 23 |
| Male | 11 | 13 | 24 |
| Ethnicity (NIH/OMB)(Participants) | Ultrasound | Fluoroscopy | Total |
|---|---|---|---|
| Hispanic or Latino | 2 | 3 | 5 |
| Not Hispanic or Latino | 19 | 23 | 42 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Race (NIH/OMB)(Participants) | Ultrasound | Fluoroscopy | Total |
|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 0 |
| Asian | 3 | 2 | 5 |
| Native Hawaiian or Other Pacific Islander | 0 | 1 | 1 |
| Black or African American | 2 | 0 | 2 |
| White | 14 | 19 | 33 |
| More than one race | 0 | 0 | 0 |
| Unknown or Not Reported | 2 | 4 | 6 |
| Presence of kidney stone indicating URS procedure(Participants) | Ultrasound | Fluoroscopy | Total |
|---|---|---|---|
| Count of participants | 21 | 26 | 47 |
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Plan to share: No
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University of California, San Francisco