Tunable microwave ablation catheter
First Claim
Patent Images
1. A medical catheter comprising:
- a flexible tubular member adapted to be inserted into a vessel in a body of a patient;
a coaxial transmission line disposed within the tubular member, the transmission line having proximal and distal ends, wherein the proximal end of the transmission line is suitable for connection to a radio frequency energy source;
a helical antenna carried by the distal end of the transmission line for generating an electric field sufficiently strong to cause tissue ablation; and
means for altering the geometry of the antenna during use in a controlled manner to alter the effective impedance of the antenna to permit tuning of the catheter during use by compensating for variations in the effective impedance of the catheter that occur during use, the antenna geometry altering means having a portion that is directly or indirectly in contact with the antenna.
3 Assignments
0 Petitions
Accused Products
Abstract
An ablation catheter is disclosed that include a mechanism for altering the impedance of the antenna during use in a controlled manner to tune the catheter. The impedance tuning may be accomplished in a variety of manners including altering the electromechanical configuration of the antenna and moving a material relative to the antenna or vice versa in order to vary the effective impedance during use. In a preferred embodiment, the ablation catheter transmits energy in the microwave frequencies and uses a coaxial transmission line as its waveguide. The antenna is preferably helical in nature and is carried by the distal end of the transmission line.
-
Citations
29 Claims
-
1. A medical catheter comprising:
-
a flexible tubular member adapted to be inserted into a vessel in a body of a patient; a coaxial transmission line disposed within the tubular member, the transmission line having proximal and distal ends, wherein the proximal end of the transmission line is suitable for connection to a radio frequency energy source; a helical antenna carried by the distal end of the transmission line for generating an electric field sufficiently strong to cause tissue ablation; and means for altering the geometry of the antenna during use in a controlled manner to alter the effective impedance of the antenna to permit tuning of the catheter during use by compensating for variations in the effective impedance of the catheter that occur during use, the antenna geometry altering means having a portion that is directly or indirectly in contact with the antenna. - View Dependent Claims (2, 3, 4, 5)
-
-
6. A medical catheter comprising:
-
a flexible tubular member adapted to be inserted into a vessel in the body of a patient; a coaxial transmission line disposed within the tubular member, the transmission line having proximal and distal ends, wherein the proximal end of the transmission line is suitable for connection to a radio frequency energy source; an antenna carried by the distal end of the transmission line for generating an electric field sufficiently strong to cause tissue ablation; and means connected to the catheter for mechanically altering the effective impedance of the antenna during use in a controlled manner to facilitate tuning the catheter by compensating for variations in the effective impedance of the catheter that occur during use. - View Dependent Claims (7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
-
-
18. A medical catheter comprising:
-
a flexible tubular member adapted to be inserted into a vessel in the body of a patient; a coaxial transmission line disposed within the tubular member, the transmission line having proximal and distal ends, a center conductor, a dielectric material journaled about the center conductor and a shield, wherein the proximal end of the transmission line is suitable for connection to a microwave energy source; an antenna carried by the distal end of the transmission line for generating an electric field sufficiently strong to cause tissue ablation; and means connected to the catheter for mechanically altering the impedance of the transmission line during use in a controlled manner to facilitate tuning the catheter by compensating for variations in the effective impedance of the catheter that occur during use. - View Dependent Claims (19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29)
-
Specification