Kidney; ObstructionPhase 2NCT05090800
Contrast Enhanced Ultrasound for Renal Obstruction
A Phase 2 study testing Definity contrast during ultrasound in people with Kidney; Obstruction and Renal Obstruction, run by University of Michigan at 1 site in United States.
Trial summary
This research is studying Definity ultrasound contrast agent, which is already approved by the Food and Drug Administration (FDA) for the ultrasound evaluation of the liver and heart. This research will investigate the ability to use ultrasound imaging with ultrasound contrast agents to evaluate kidney obstruction. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Kidney; Obstruction, Renal Obstruction
- What is being tested?
- Definity contrast during ultrasound
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 10 participants
- Where
- 1 siteUnited States
- Study dates
- 3 Dec 2021to 23 Sep 2025
- Phase
- Phase 2
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Unilateral renal obstruction confirmed by Nuclear Medicine MAG3 Dynamic Renal Scan (diuretic t (time) ½ >20 minutes)
- Obstructed kidney with differential function >15% confirmed by Nuclear Medicine Mercaptoacetyltriglycine (MAG3) Dynamic Renal Scan within less or equal (<=) 6 months from enrollment
- Patient has elected to move forward with pyeloplasty or proximal ureteroureterostomy to correct the obstruction
Who cannot join
- Solitary kidney
- Any abnormalities of contralateral collecting system (for example (e.g.) hydronephrosis, renal calculi, duplicated collecting system)
- Known vesicoureteral reflux
- Ureteral stent in place in the obstructive kidney
- Patients without a Nuclear Medicine MAG3 Dynamic Renal Scan
- Previous history of hypersensitivity to Ultrasound Contrast Agents or Definity (perflutren lipid microspheres))
Show all 11Show fewer
- Previous sensitivity to polyethylene glycol
- Pregnant or breastfeeding females
- Body mass index (BMI) >=40 without prior ultrasound confirming ability to adequately visualize the kidneys (Elevated BMI is known to decrease ability to image the kidneys)
- Global renal function with a Glomerular Filtration Rate (GFR) <30 (chronic kidney disease Stage 4 \& 5 excluded)
- Unstable cardiopulmonary conditions (acute myocardial infarction, acute coronary artery syndromes, worsening or unstable congestive heart failure, serious ventricular arrhythmias, presence of a cardiac shunt)
Trial locations and contacts
1 site in 1 country.
About this study
This research is studying Definity ultrasound contrast agent, which is already approved by the Food and Drug Administration (FDA) for the ultrasound evaluation of the liver and heart. This research will investigate the ability to use ultrasound imaging with ultrasound contrast agents to evaluate kidney obstruction.
Eligible participants that are enrolled will have two visits (one before and one after the planned surgery to relieve the kidney obstruction).
- Conditions
- Kidney; Obstruction, Renal Obstruction
- Being tested
- Definity contrast during ultrasound
- Keywords
- ultrasound imaging, ultrasound contrast agents, kidney tissue, hydronephrosis
- Medical subject headings
- Bites and Stings, Hydronephrosis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Definity contrast during ultrasoundDrug
Also called Perflutren Lipid Microsphere
Participants will undergo an ultrasound contrast evaluation of both kidneys. This will include placement of an intravenous (IV) catheter in a vein and the delivery of Definity ultrasound contrast agent through the IV. Imaging will be completed for each kidney. The proposed total dose for adult patients will not exceed 20 microliters/kilograms (kg). Each individual dose not to exceed 10 microliters/kg. At initiation of patient studies, the dose will start at 10 microliters/kg for the first injection and a second 10 microliters/kg dose to evaluate the contralateral kidney. However, if ultrasound findings in patient studies demonstrate a dose that is too high (unable to make accurate ultrasound assessment), the dose will be reduced.
| Study group | Role | What they receive |
|---|---|---|
| Definity contrast agent | Experimental | Not described Receives: Drug: Definity contrast during ultrasound |
What is being measured
The primary outcome is the main question the study is designed to answer.
Time to peak (TTP) ultrasound measurements
Differences in ultrasound contrast measurements between obstructed and normal kidneys
Measured: Immediately after contrast injected (approximately 30 minutes)
Peak intensity (PI) ultrasound measurements
Differences in ultrasound contrast measurements between obstructed and normal kidneys
Measured: Immediately after contrast injected (approximately 30 minutes)
Mean transit time (MTT) ultrasound measurements
Differences in ultrasound contrast measurements between obstructed and normal kidneys
Measured: Immediately after contrast injected (approximately 30 minutes)
Area under the curve (AUC) ultrasound measurements
Differences in ultrasound contrast measurements between obstructed and normal kidneys
Measured: Immediately after contrast injected (approximately 30 minutes)
Ratio of plateau and peak intensity ultrasound Measurements
Differences in ultrasound contrast measurements between obstructed and normal kidneys
Measured: Immediately after contrast injected (approximately 30 minutes)
Secondary outcomes (6)
Contrast arrival time (AT) ultrasound measurements
Differences in ultrasound contrast measurements between obstructed and normal kidneys
Measured: Immediately after contrast injected (approximately 30 minutes)
Enhanced slope ultrasound measurements
Differences in ultrasound contrast measurements between obstructed and normal kidneys
Measured: Immediately after contrast injected (approximately 30 minutes)
Fall time (FT) ultrasound measurements
Differences in ultrasound contrast measurements between obstructed and normal kidneys
Measured: Immediately after contrast injected (approximately 30 minutes)
Time from peak to baseline (TPB) ultrasound measurements
Differences in ultrasound contrast measurements between obstructed and normal kidneys
Measured: Immediately after contrast injected (approximately 30 minutes)
Final plateau intensity ultrasound measurements
Differences in ultrasound contrast measurements between obstructed and normal kidneys
Measured: Immediately after contrast injected (approximately 30 minutes)
Initial intrarenal microcirculatory transmit time ultrasound measurements
Differences in ultrasound contrast measurements between obstructed and normal kidneys
Measured: Immediately after contrast injected (approximately 30 minutes)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted25 Oct 2021
- Study start3 Dec 2021
- Primary completion23 Sep 2025
- Study completion23 Sep 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Kidney; ObstructionStudies of the same condition, open and under way.
- More trials run by University of MichiganThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Diagnosis
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 10 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Michigan
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Sapan Ambani, University of Michigan
- Investigators
- Sapan N Ambani, MD, Principal investigator, University of Michigan
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05090800
- Sponsor's protocol ID
- HUM00193843
- Status last verified
- Oct 2025
- First submitted
- 11 Oct 2021
- Last updated
- 2 Oct 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 2 Oct 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Contrast Enhanced Ultrasound for Renal Obstruction
- ClinicalTrials.gov ID
- NCT05090800
- Acronym / sponsor ID
- HUM00193843
- Conditions
- Kidney; Obstruction, Renal Obstruction
- Keywords
- ultrasound imaging, ultrasound contrast agents, kidney tissue, hydronephrosis
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 10 participants (actual)
- Lead sponsor
- University of MichiganUniversity, hospital or other
- Study start
- 3 Dec 2021 (actual)
- Primary completion
- 23 Sep 2025 (actual)
- Study completion
- 23 Sep 2025 (actual)
- First posted
- 25 Oct 2021 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This research is studying Definity ultrasound contrast agent, which is already approved by the Food and Drug Administration (FDA) for the ultrasound evaluation of the liver and heart. This research will investigate the ability to use ultrasound imaging with ultrasound contrast agents to evaluate kidney obstruction.
Eligible participants that are enrolled will have two visits (one before and one after the planned surgery to relieve the kidney obstruction).
Study design
- Primary purpose
- Diagnosis
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Definity contrast agent | Experimental | Drug: Definity contrast during ultrasound |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- Unilateral renal obstruction confirmed by Nuclear Medicine MAG3 Dynamic Renal Scan (diuretic t (time) ½ >20 minutes)
- Obstructed kidney with differential function >15% confirmed by Nuclear Medicine Mercaptoacetyltriglycine (MAG3) Dynamic Renal Scan within less or equal (<=) 6 months from enrollment
- Patient has elected to move forward with pyeloplasty or proximal ureteroureterostomy to correct the obstruction
Key exclusion criteria (11 listed)
- Solitary kidney
- Any abnormalities of contralateral collecting system (for example (e.g.) hydronephrosis, renal calculi, duplicated collecting system)
- Known vesicoureteral reflux
- Ureteral stent in place in the obstructive kidney
- Patients without a Nuclear Medicine MAG3 Dynamic Renal Scan
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Definity contrast during ultrasoundAlso: Perflutren Lipid MicrosphereParticipants will undergo an ultrasound contrast evaluation of both kidneys. This will include placement of an intravenous (IV) catheter in a vein and the delivery of Definity ultrasound contrast agent through the IV. Imaging will be completed for each kidney. The proposed total dose for adult patients will not exceed 20 microliters/kilograms (kg). Each individual dose not to exceed 10 microliters/kg. At initiation of patient studies, the dose will start at 10 microliters/kg for the first injection and a second 10 microliters/kg dose to evaluate the contralateral kidney. However, if ultrasound findings in patient studies demonstrate a dose that is too high (unable to make accurate ultrasound assessment), the dose will be reduced. | Drug | Definity contrast agent |
Primary outcome
Time to peak (TTP) ultrasound measurements
Time frame: Immediately after contrast injected (approximately 30 minutes)
Differences in ultrasound contrast measurements between obstructed and normal kidneys
Peak intensity (PI) ultrasound measurements
Time frame: Immediately after contrast injected (approximately 30 minutes)
Differences in ultrasound contrast measurements between obstructed and normal kidneys
Mean transit time (MTT) ultrasound measurements
Time frame: Immediately after contrast injected (approximately 30 minutes)
Differences in ultrasound contrast measurements between obstructed and normal kidneys
Area under the curve (AUC) ultrasound measurements
Time frame: Immediately after contrast injected (approximately 30 minutes)
Differences in ultrasound contrast measurements between obstructed and normal kidneys
Ratio of plateau and peak intensity ultrasound Measurements
Time frame: Immediately after contrast injected (approximately 30 minutes)
Differences in ultrasound contrast measurements between obstructed and normal kidneys
6 secondary outcomes
Contrast arrival time (AT) ultrasound measurements
Time frame: Immediately after contrast injected (approximately 30 minutes)
Enhanced slope ultrasound measurements
Time frame: Immediately after contrast injected (approximately 30 minutes)
Fall time (FT) ultrasound measurements
Time frame: Immediately after contrast injected (approximately 30 minutes)
Time from peak to baseline (TPB) ultrasound measurements
Time frame: Immediately after contrast injected (approximately 30 minutes)
Final plateau intensity ultrasound measurements
Time frame: Immediately after contrast injected (approximately 30 minutes)
Initial intrarenal microcirculatory transmit time ultrasound measurements
Time frame: Immediately after contrast injected (approximately 30 minutes)
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 2 Oct 2025.
- Individual participant dataSharing planned: No
Related trials for Kidney; Obstruction
RecruitingPhase 1
Serial Amnioinfusions as Regenerative Therapy for Pulmonary Hypoplasia
Renal Failure Congenital, Congenital Renal Anomaly Nos
Recruiting
Effects of Percutaneous Transluminal Renal Angioplasty of Atherosclerotic Renal Artery Stenosis in High-Risk Patients.
Renovascular Hypertension, Renovascular Hypertension With Renal Failure
Not yet recruitingPhase 4
Effect of Oxybutynin on Opioid Use After Urologic Surgery in Children
Ureteropelvic Junction Obstruction, Hypospadias
Not yet recruiting
Intertransverse Process Block Versus Erector Spinae Plane Block for Postoperative Analgesia After Percutaneous Nephrolithotomy
Kidney Stones, Urolithiasis, Hypocitraturia, Pain, Postoperative
RecruitingObservational study
Rare Disease Patient Registry & Natural History Study - Coordination of Rare Diseases at Sanford
Rare Disorders, Undiagnosed Disorders
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Sapan N Ambani, MD principal investigator
University of Michigan
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Definity contrast during ultrasound in people with Kidney; Obstruction and Renal Obstruction, run by University of Michigan at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 11 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 2 Oct 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Time to peak (TTP) ultrasound measurements (time frame: Immediately after contrast injected (approximately 30 minutes)). The study lists 5 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 2 Oct 2025.