# Ultrasound-guided Intrinsic Threshold Histotripsy for the Non-invasive Ablation of Uterine Fibroids

> **NIH NIH R21** · VIRGINIA POLYTECHNIC INST AND ST UNIV · 2022 · $191,220

## Abstract

PROJECT SUMMARY
The goal of this project is to develop intrinsic threshold histotripsy as a non-thermal focused ultrasound (FUS)
technique for the non-invasive ablation of uterine fibroids. Uterine fibroids (leiomyomas) are the most common
benign tumors in women of reproductive age, resulting in over 250,000 hospital admissions and 200,000
hysterectomies annually. The gold standard for uterine fibroids is hysterectomy, a surgical procedure that
requires extended hospitalization and recovery time, and results in the loss of reproductive function. Thermal
FUS has emerged as a non-invasive method for the management and conservation of uterine function. However,
complications due to thermal spread, reliance on MRI for image-guidance, slow treatment times, and slow
resorption of the fibroids after treatment have limited the widespread use of thermal FUS. This proposal
develops intrinsic threshold histotripsy for the ablation of uterine fibroids. While histotripsy has shown the
potential to overcome limitations of thermal ablation in many clinical applications, the technique has previously
been shown to be less effective in highly fibrous tissues, which has thus far prevented histotripsy from being
developed for treating uterine fibroids. Recently, our team completed a proof-of-concept study demonstrating
that histotripsy can effectively ablate human uterine fibroids using intrinsic threshold histotripsy techniques. In
this project, we will investigate the optimal histotripsy treatment methods for the rapid ablation of uterine fibroids
under real-time ultrasound image-guidance. In Aim 1, we will compare the histotripsy cavitation bubble cloud
behavior and tissue ablation generated by multi-cycle (shock-scattering histotripsy) and single-cycle (intrinsic
threshold histotripsy) methods using a wide range of potential histotripsy pulsing parameters. Experiments will
be conducted in mechanically-tunable tissue phantoms that mimic the properties of fibrous tissue as well as ex
vivo experiments using excised human uterine fibroids. In Aim 2, we will test in vivo safety and efficacy of intrinsic
threshold histotripsy ablation in a small animal model. The successful completion of these aims will demonstrate
the safety and efficacy of TEH for the non-invasive treatment of uterine fibroids.

## Key facts

- **NIH application ID:** 10509018
- **Project number:** 1R21HD109631-01
- **Recipient organization:** VIRGINIA POLYTECHNIC INST AND ST UNIV
- **Principal Investigator:** Eli Vlaisavljevich
- **Activity code:** R21 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2022
- **Award amount:** $191,220
- **Award type:** 1
- **Project period:** 2022-08-15 → 2024-07-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10509018

## Citation

> US National Institutes of Health, RePORTER application 10509018, Ultrasound-guided Intrinsic Threshold Histotripsy for the Non-invasive Ablation of Uterine Fibroids (1R21HD109631-01). Retrieved via AI Analytics 2026-05-26 from https://api.ai-analytics.org/grant/nih/10509018. Licensed CC0.

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