A broad band microwave applicator for heating tumours

Abstract

The applicator consists basically of a length of semirigid coaxial line cable (Americon) which is able to move along the inside of a hypodermic needle (Fig. 1). The cable is approximately 9.5 cm long and has an outer conductor with a diameter of 0.086 cm. The inner conductor has a diameter of 0.02 cm and projects 0.6 cm from one end of the cable (I, Fig. 1). The other end of the cable is soldered to a miniature plug A (Americon, ARMM series) which enables the applicator to be connected to a microwave generator operating at a frequency of 2.45 GHz. This connector (A) is supported on a brass collar B, connected to the piston C which is 2.3 cm long and 0.32 cm in diameter. The coaxial line cable is rigidly glued to the inside of C using an epoxy resin. The piston C moves inside a closely fitting cylinder F which has an external diameter of 0.71 cm and is 3.2 cm long.