Database of Tissue Properties

The IT'IS material parameter database aims at providing the values of EM and thermal material parameters of biological tissues to the modeling community in a free, easily accessible, and dynamically evolving manner. It is based on a comprehensive scientific literature review and shall be continuously updated. The IT'IS Foundation, a non-profit and independent organization, is committed to the long-term maintenance of this material parameter database, relying strongly on the input of its users, who we encourage to engage via a specific forum. This database is part of the ongoing effort of IT'IS to create the Virtual Population, a series of highly detailed anatomical models.

Although the Virtual Population models have been employed to simulate a wide range of physical phenomena, they were initially developed to simulate EM-tissue interactions and EM-induced heating. The Virtual Population models are distributed with a list indicating which tissue parameter assignments should be used for specific tissues and organs. The SEMCAD X and Sim4Life simulation software packages are able to import the material database and automatically assign tissue parameter values to the Virtual Population models.

The IT’IS material parameter database is based on an extensive literature study for the thermal parameters and the Gabriel dispersion relations [1] for the dielectric parameters. The current version of the IT’IS material database has been developed by merging the internal IT’IS material parameter database (which in turn was based on 11 review articles and reports) with values from the recently published database from McIntosh and Anderson [2] and extending it with values from additional literature sources.

The database aims not only at providing the most up-to-date and comprehensive estimation of tissue material parameter values but also information about the spread and standard deviation per tissue for the different thermal parameters. This is important when assessing the uncertainty contribution for a quantity of interest due to the selection of the material parameters. For some material parameters (e.g., perfusion), the variation can be large, which in turn can strongly affect modeling results.

The IT'IS material parameter database is envisioned as a continuously developing and improving web resource. Although revised versions of the database will be published (e.g., including additional published data or reflecting refined considerations), previous versions will remain accessible. In addition, an affiliated user forum is maintained, where users can suggest additional references, question assumptions behind the current values, or discuss possible improvements. The goal is to launch a community effort to create a most comprehensive and accurate reference database for EM and thermal simulations involving human models. In the future, the material database could be extended to cover other physical and physiological properties of tissues as well (ultrasound propagation and absorption, mechanical elasticity, etc).

Please use the following citation when referring to our database:

Hasgall PA, Neufeld E, Gosselin MC, Klingenböck A, Kuster N, "IT'IS Database for thermal and electromagnetic parameters of biological tissues", September 26th, 2011. www.itis.ethz.ch/database

References:

[1] C. Gabriel. Compilation of the Dielectric Properties of Body Tissues at RF and Microwave Frequencies, Report N.AL/OE-TR- 1996-0037, Occupational and environmental health directorate, Radiofrequency Radiation Division, Brooks Air Force Base, Texas (USA), 1996.

[2] R. L. Mcintosh and V. Anderson. A Comprehensive Tissue Properties Database Provided for the Thermal Assessment of a Human at Rest, Biophysical Reviews and Letters, vol. 5, no. 3, pp. 129-151, 2010.