Microwave thermotherapy: Study of hot-spots induced by electromagnetic surface waves

This paper is a contribution to theory of microwave applicators used e.g. in cancer treatment by electromagnetically induced hyperthermia, but discussed problems can occur in microwave thermotherapy in general. Paper deals with a study of mechanism of excitations of surface waves propagating around the treated area - one kind of parasitic effects, which can significantly complicate real treatment of patients (these superficial waves can create superficial hot spots outside treated area). Appropriate treatment planning by aid of numerical simulations of SAR distribution can prevent such cases. In this paper we will demonstrate a possibility to eliminate excitations of surface waves by optimization of water bolus shape and dimensions.