Investigations on an improved interstitial antenna used for microwave hyperthermia and the specific absorption rate distribution within biological tissues.

Hepatocellular carcinoma is one of the common tumors in the world, which leads to more than 600,000 deaths per year.Microwave hyperthermia has been widely used in hepatocellular carcinoma treatment, whereby the cancer cells are heated and killed by making use of the different thermal sensitivity of the cancer cells and normal cells. Monopole is used to be microwave radiator in recent years; however, the ablation region is elongated along the antenna insertion direction so that the skin and normal tissue around the tumor is also heated unexpectedly. It is desirable to generate a heating region in the vicinity of the antenna tip in a spherical manner. To solve the issue, a coaxial-slot antenna with choke is proposed in the article, the specific absorption rate (SAR) distribution around antenna is computed by means of the finite difference time domain method. By comparison with the SAR distribution caused by monopole antenna, it is clear that no unnecessary heating region is generated near the surface of the body when the improved antenna is used. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 54:405-409, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26553 [ABSTRACT FROM AUTHOR]