Contrast Enhanced Ultrasound for Renal Obstruction

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 Overview

• Status: Completed
• Conditions: Kidney; Obstruction; Renal Obstruction
• Intervention / Treatment: Drug: Definity contrast during ultrasound

• Study Type: Interventional
• Enrollment (Actual): 10
• Phase: Phase 2

Contacts and Locations

Study Locations

• United States
  • Michigan
    • Ann Arbor, Michigan, United States, 48109
      • University of Michigan

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

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)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Definity contrast agent

Drug: Definity contrast during ultrasound; 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.; Other Names: Perflutren Lipid Microsphere

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Time to peak (TTP) ultrasound measurements	Differences in ultrasound contrast measurements between obstructed and normal kidneys	Immediately after contrast injected (approximately 30 minutes)
Peak intensity (PI) ultrasound measurements	Differences in ultrasound contrast measurements between obstructed and normal kidneys	Immediately after contrast injected (approximately 30 minutes)
Mean transit time (MTT) ultrasound measurements	Differences in ultrasound contrast measurements between obstructed and normal kidneys	Immediately after contrast injected (approximately 30 minutes)
Area under the curve (AUC) ultrasound measurements	Differences in ultrasound contrast measurements between obstructed and normal kidneys	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	Immediately after contrast injected (approximately 30 minutes)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Contrast arrival time (AT) ultrasound measurements	Differences in ultrasound contrast measurements between obstructed and normal kidneys	Immediately after contrast injected (approximately 30 minutes)
Enhanced slope ultrasound measurements	Differences in ultrasound contrast measurements between obstructed and normal kidneys	Immediately after contrast injected (approximately 30 minutes)
Fall time (FT) ultrasound measurements	Differences in ultrasound contrast measurements between obstructed and normal kidneys	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	Immediately after contrast injected (approximately 30 minutes)
Final plateau intensity ultrasound measurements	Differences in ultrasound contrast measurements between obstructed and normal kidneys	Immediately after contrast injected (approximately 30 minutes)
Initial intrarenal microcirculatory transmit time ultrasound measurements	Differences in ultrasound contrast measurements between obstructed and normal kidneys	Immediately after contrast injected (approximately 30 minutes)

Collaborators and Investigators

• Sponsor: University of Michigan
• Investigators: Principal Investigator: Sapan N Ambani, MD, University of Michigan

Study record dates

Study Major Dates

• Study Start (Actual): December 3, 2021
• Primary Completion (Actual): September 23, 2025
• Study Completion (Actual): September 23, 2025

Study Registration Dates

• First Submitted: October 11, 2021
• First Submitted That Met QC Criteria: October 11, 2021
• First Posted (Actual): October 25, 2021

Study Record Updates

• Last Update Posted (Estimated): October 2, 2025
• Last Update Submitted That Met QC Criteria: October 1, 2025
• Last Verified: October 1, 2025

More Information

Terms related to this study

• Keywords: ultrasound imaging; ultrasound contrast agents; kidney tissue; hydronephrosis
• Additional Relevant MeSH Terms: Urogenital Diseases; Wounds and Injuries; Male Urogenital Diseases; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Chemically-Induced Disorders; Poisoning; Bites and Stings; Hydronephrosis
• Other Study ID Numbers: HUM00193843

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No