Microwave applicator/receiver apparatus

Claim 1

For use in medical treatment of living tissue a microwave applicator/receiver device capable of applying microwave-frequency radiant energy to living tissue by way of insertion thereof through an opening into the body and of receiving similar energy radiating from within such tissue while in contact with said tissue, said device comprising an inner electrical conductor and an outer electrical conductor substantially shielding said inner conductor in a non-resonant transmission line configuration capable of propagating microwave energy in a frequency band suitable for heating living tissue, said inner conductor having an unshielded portion extending a distance beyond said outer conductor, and a helical coil surrounding said extending portion of said inner conductor and including first and second means connected between the ends of said outer and inner conductors respectively, for providing a traveling wave pattern of microwave radiation into tissue which pattern is characterized by substantially uniform intensity distribution over a prescribed spatial distribution within said tissue thus providing uniform heating absent hot-spots over the length of said helical coil, said first means providing a conductive connection from the outer conductor to the helical coil, said second means comprising a substantially radial conductor interconnecting the helical coil with the inner conductor extending portion with an absence of any conductor extending axially substantially beyond said helical coil, said helical coil having multiple wire turns each separated from the next by an inter-turn spacing greater than the diameter of the helical conductor wire, the axial length of said helical coil being substantially greater than the diameter of the helical coil, and including a substantially smooth dielectric sleeve covering at least said helical coil.