# Characterization of microvasculature in kidney transplant by super-resolution ultrasound imaging

> **NIH NIH R01** · MAYO CLINIC ROCHESTER · 2024 · $505,741

## Abstract

PROJECT SUMMARY
End-stage kidney disease (ESKD) affects a significant number of patients in the U.S. (>785,000 in 2018), and
presents substantial medical, social, and economic challenges. Kidney transplantation is the preferred
treatment for ESKD. However, there is a pressing unmet clinical need for better methods that allow for
noninvasive, accurate, and frequent characterization and monitoring of kidney allograft injury. Such methods
are critical for enhancing long-term allograft survival and improving the quality of life for the kidney transplant
recipients. The change of kidney parenchymal microvasculature and perfusion has been shown to play a vital
role in the progression of allograft injury, while noninvasive tools for imaging and quantification of allograft
microvasculature are still lacking. In this project, we will develop a novel noninvasive, robust, and translatable
super-resolution ultrasound imaging (SRUI) technology. This technology aims to provide imaging and
quantification of parenchymal microvasculature to enable reliable assessment of allograft injuries. In our pilot
patient study of transplant kidneys, parameters derived from SRUI correlate strongly with pathology (r ≥ 0.9).
Aim 1: Technical development. We will advance and optimize the novel SRUI technology for kidney allograft
imaging and quantification. New signal enhancement and localization methods will be developed to improve
the overall performance of SRUI in clinical settings. We will advance the SRUI to 3D to enable more
comprehensive assessments of the graft microvasculature. We will develop novel quantitative SRUI metrics,
including microvascular density, tortuosity, flow speed, cortex perfusion and micro-resistive index.
Aim 2: Clinical patient study. We will study 158 patients to investigate the value of SRUI for kidney allograft
assessment using biopsy histology as validation. The association of SRUI metrics with histological injuries will
be assessed. The ability of SRUI, conventional ultrasound, and clinical measures (eGFR, proteinuria) to
distinguish between kidney allografts with varying degrees of histological injuries will be evaluated. We will also
assess the inter-sonographer reproducibility of the SRUI technology in a subset of 46 patients.
Aim 3: Longitudinal follow-up study. We will conduct a longitudinal follow-up study in 62 patients to assess
the efficacy of SRUI in monitoring and predicting the progression of allograft injury, using biopsy histology as
validation. The association of changes in SRUI metrics with the changes in histological injuries from 1-year to
2-year post-transplant will be assessed. We will study if SRUI metrics or combined metrics at 1-year post-
transplant, or the changes of these metrics from 1-year to 2-year, can distinguish between allografts without
and with histological worsening during this period.
Successful completion of this project will lead to a noninvasive, accessible, cost-effective, and translatable tool
to addre...

## Key facts

- **NIH application ID:** 10856000
- **Project number:** 1R01DK138998-01
- **Recipient organization:** MAYO CLINIC ROCHESTER
- **Principal Investigator:** Chengwu Huang
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $505,741
- **Award type:** 1
- **Project period:** 2024-05-09 → 2029-03-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10856000

## Citation

> US National Institutes of Health, RePORTER application 10856000, Characterization of microvasculature in kidney transplant by super-resolution ultrasound imaging (1R01DK138998-01). Retrieved via AI Analytics 2026-05-25 from https://api.ai-analytics.org/grant/nih/10856000. Licensed CC0.

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