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Tissue and Blood Mimicking Materials for High Intensity Therapeutic Ultrasound

Catalog of Regulatory Science Tools to Help Assess New Medical Devices 

 

This regulatory science tool is a lab method that may be helpful while evaluating high intensity therapeutic ultrasound (HITU) devices.

 

Technical Description

This tool is a tissue mimicking material (TMM) and blood mimicking material (BMM) developed for the acoustic and thermal characterization of therapeutic ultrasound devices, especially high intensity therapeutic ultrasound (HITU) applications. The recipes and protocols can be used to produce soft tissue and human blood phantoms that were found to have relevant acoustic and thermal properties for therapeutic ultrasound thermal safety and performance evaluation while also being cost-effective.

Intended Purpose

The tissue and blood mimicking materials provide a phantom bench testing tool for demonstrating HITU exposimetry performance, validating targeting accuracy, and evaluating thermal safety of therapeutic ultrasound devices[3].

Testing

Both acoustic and thermal properties of the TMM and BMM were fully characterized with established engineering methods[1] to demonstrate physical properties comparable to soft tissues and human blood parameters[2].

Limitations

  • For device performance testing, independent phantom property measurement (attenuation, sound speed and thermal property, etc) before each ultrasound experiment is recommended (new batch or short-term storage) in order to obtain precise property values for inter-study comparison or simulation purposes.
  • Substantial cavitation or boiling bubble activity within the focal area could perturb the ultrasound field and deviate temperature recording at high acoustic power or low frequency within hydrogel-based phantom materials.

Supporting Documentation

  1. Liu Y. and Maruvada S. Development and characterization of polyurethane-based tissue and blood mimicking materials for high intensity therapeutic ultrasound. J. Acoust. Soc. Am. 151, 3043-51, 2022.https://pubmed.ncbi.nlm.nih.gov/35649924/.
  2. Duck F. Physical properties of tissue: A complete reference book. London: Academic Press. 1990
  3. IEC 60601-2-62:2013: Particular requirements for the basic safety and essential performance of high intensity therapeutic ultrasound (HITU) equipment.

Contact

Tool Reference

  • In addition to citing relevant publications please reference the use of this tool using RST24TU01.01