Using ultrasound with contrast agents to evaluate kidney obstruction

Contrast Enhanced Ultrasound for Renal Obstruction

Phase 2 Interventional University of Michigan · NCT05090800

This study is testing if a special ultrasound with a contrast agent can help doctors better see and understand kidney blockages in patients who are scheduled for surgery.

Quick facts

PhasePhase 2
Study typeInterventional
Enrollment10 (estimated)
Ages18 Years and up
SexAll
SponsorUniversity of Michigan Academic / other
Locations1 site (Ann Arbor, Michigan)
Trial IDNCT05090800 on ClinicalTrials.gov

What this trial studies

This research investigates the use of the Definity ultrasound contrast agent, which is FDA-approved for liver and heart evaluations, to assess kidney obstruction. Participants will undergo two visits, one prior to and one after planned surgery to relieve the obstruction. The study aims to determine the effectiveness of ultrasound imaging enhanced with contrast agents in evaluating renal obstruction. The focus is on patients with unilateral renal obstruction confirmed by specific nuclear medicine scans.

Who should consider this trial

Good fit: Ideal candidates are patients with unilateral renal obstruction confirmed by specific imaging tests who are planning to undergo surgery to correct the obstruction.

Not a fit: Patients with a solitary kidney or significant abnormalities in the contralateral collecting system may not benefit from this study.

Why it matters

Potential benefit: If successful, this approach could provide a non-invasive method to better evaluate and manage kidney obstructions.

How similar studies have performed: While the use of ultrasound contrast agents is established in other areas, this specific application for renal obstruction is novel and has not been extensively tested.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* 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

Exclusion Criteria:

* 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))
* 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)

Where this trial is running

Ann Arbor, Michigan

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions KidneyObstructionRenal Obstructionultrasound imagingultrasound contrast agentskidney tissuehydronephrosis
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.