Potential hazards of radiative electromagnetic hyperthermia in the presence of multiple metallic surgical clips

Abstract

Three-dimensional computer simulations of a patient under consideration for heating by the BSD Sigma 60 phased array applicator showed marked specific absorption rate (SAR) enhancement in the region where there was a concentration of metallic surgical clips. Subsequent tests in tissue-equivalent phantom material confirmed that metallic objects much shorter than the wavelength in tissue of the radiative electromagnetic field can cause significant changes in the power deposition near the implanted metal. The placement of extensive numbers of surgical clips may therefore hinder the ability to subsequently utilize radiative electromagnetic heating modalities.

Key Words:

• SAR
• metallic objects
• 3-D modeling
• deep hyperthermia