Radiation applicator for microwave medical treatment
A radiation applicator with a dielectric body ( 2 ) surrounding the antenna. The dielectric body ( 2 ) is comprised of three sections ( 3, 4 and 5 ) with different dielectric constants to provide broad-band matching of the applicator to surrounding material. Washers ( 10 ) and ( 11 ) are mounted on the antenna to act as reflectors.
1. A method for treating tissue using microwave, comprising:
inserting an applicator into a target site, the applicator comprising:
an outer conductor;
an inner conductor;
a first body having a proximal end; wherein the first body is comprised of a first material having a first dielectric constant; wherein the proximal end of the first body is configured to extend coaxially within the outer conductor;
a second body having a sharp end and a cavity; wherein the second body is comprised of a second material having a second dielectric constant; wherein the sharp end is configured to pierce tissue;
a tuning reflector comprised of a third material having a third dielectric constant; wherein the tuning reflector is configured to be inside of the cavity of the second body; and
wherein the first dielectric constant, the second dielectric constant, and the third dielectric constant are all different;
applying microwave energy from the applicator to the target site.
2. The method of claim 1 , wherein the inner conductor is coaxially positioned within the outer conductor for a selected distance.
3. The method of claim 2 , wherein the target site is comprised of human tissue.
4. The method of claim 3 , wherein the tuning reflector comprises a washer.
5. The method of claim 1 , wherein the inner conductor further comprises a distal end.
6. The method of claim 5 , wherein the tuning reflector is connected to the distal end of the inner conductor.
7. The method of claim 1 , further comprising the step:
transferring energy at a frequency of up to 3 GHz.
8. The method of claim 7 , wherein the energy is transferred at a frequency of 2.45 GHz.
9. The method of claim 8 , wherein the energy is transferred at a power of 50 watts.
10. The method of claim 1 , wherein the outer conductor is rigid.
11. The method of claim 1 , wherein the outer conductor is flexible.
12. The method of claim 1 , wherein the applicator further comprises an antenna.
13. The method of claim 1 , further comprising the step:
avoiding local surface heating surrounding the target site.
14. The method of claim 1 , further comprising the step:
imaging the applicator to guide the applicator into the target site.
15. The method of claim 14 , wherein the imaging is ultrasound.
16. The method of claim 1 , wherein the sharp end of the second body is tapered.
17. A method for treating tissue using microwave, comprising:
inserting an applicator into a target site, the applicator comprising an antenna; wherein the antenna comprises:
an outer conductor;
an inner conductor;
a first body having a proximal end; wherein the first body is comprised of a first material having a first dielectric constant; wherein the proximal end of the first body is configured to extend coaxially within the outer conductor;
a second body having a sharp end and a cavity; wherein the second body is comprised of a second material having a second dielectric constant; wherein the sharp end is configured to pierce tissue;
a tuning reflector comprised of a third material having a third dielectric constant; wherein the tuning reflector is configured to be inside of the cavity of the second body; and
wherein the first dielectric constant, the second dielectric constant, and the third dielectric constant are all different;
applying microwave energy from the applicator to the target site; wherein the microwave energy is applied at a frequency of 2.45 GHz.
18. A method for treating tissue using microwave, comprising:
inserting an applicator into a target site, the applicator comprising an antenna; wherein the antenna comprises:
an outer conductor;
an inner conductor;
a first body having a proximal end; wherein the first body is comprised of a first material having a first dielectric constant; wherein the proximal end of the first body is configured to extend coaxially within the outer conductor;
a second body having a sharp end; wherein the second body is comprised of a second material having a second dielectric constant; wherein the sharp end is configured to pierce tissue;
a tuning reflector comprised of a third material having a third dielectric constant; and
wherein the first dielectric constant, the second dielectric constant, and the third dielectric constant are all different;
applying microwave energy from the applicator to the target site; wherein the microwave energy is applied at a frequency of 2.45 GHz.
19. The method of claim 16 , wherein the second body comprises a cavity.
20. The method of claim 17 , wherein the tuning reflector is configured to be inside of the cavity of the second body.