Patent ID: 6706040
Filing Date: 2004-03-16
Classification: A61B

Abstract:
An invasive probe assembly for therapeutic treatment, the probe assembly comprising:a coaxial feed line having an inner conductor, an outer conductor, and an insulating sleeve axially surrounding the outer conductor, the feed line configured for electrical contact to an RF source configured to provide RF energy having selected characteristics including a prescribed operating frequency; and a probe having a rigid probe shaft and an antenna positioned therein, the antenna including a first dipole region at a distal end of the probe shaft and connected to the inner conductor of the feed line, the first dipole region having a rounded metallic tip, a second dipole region proximally spaced therefrom, forming a dipole axis, the second dipole region having a radiating skirt electricalliy connected at a distal end to the outer conductor of the feed line and therefrom axially spaced from the outer conductor to a proximal end the skirt, and a cylindrical insulator disposed between the outer conductor and the skirt, thereby forming a choke at the prescribed operating frequency; wherein the length of the choke is substantially a quarter wavelength as determined for propagation of the provided energy through the cylindrical insulator, and a structural spacer formed of dielectric material disposed between the dipole regions along the dipole axis.