Apparatus and methods for the treatment of tissue using microwave energy
Systems and methods for delivering microwave energy to skin are provided, such that a focal zone of destructive heat is generated in the upper sub-dermis, mid-dermis, and/or lower dermis. This microwave therapy may be used for hair removal, treatment of acne, skin tightening, treatment of toe nail fungus, or sweat reduction. According to one embodiment, a system can include a microwave applicator having a distal treatment portion that includes at least one microwave antenna, a cooling system, and vacuum features. In some embodiments, the interaction between incident waves transmitted from the microwave applicator and reflected waves may be used to generate a standing wave with a peak energy density in selected regions of the dermis.
1. A microwave applicator ( 14 ), comprising a distal treatment portion ( 104 ) configured to attach to a handle portion ( 102 ), the distal treatment portion ( 104 ) comprising:
an antenna housing ( 119 );
a cooling assembly ( 162 ) disposed in the antenna housing ( 119 ), the cooling assembly ( 162 ) comprising;
a cooling chamber ( 110 );
a cooling plate ( 112 ) at a distal end of the cooling chamber ( 110 );
cooling fluid ( 118 ) in the cooling chamber ( 110 );
cooling fluid conduits ( 117 ) connected to the cooling chamber ( 110 ) to supply the cooling fluid ( 118 ) to the cooling chamber ( 110 );
a vacuum assembly ( 164 ) disposed in the antenna housing ( 119 ), the vacuum assembly ( 164 ) comprising:
an acquisition chamber ( 114 ), wherein the cooling plate ( 112 ) forms a proximal wall of the acquisition chamber ( 114 );
a vacuum port ( 120 ) connecting the acquisition chamber ( 114 ) to a vacuum conduit ( 107 );
an antenna assembly ( 150 ) disposed in the antenna housing ( 119 ), the antenna assembly ( 150 ) comprising:
an antenna substrate ( 108 );
a patch antenna disposed on the antenna substrate ( 108 );
cutouts ( 134 ) in the antenna substrate configured to accommodate the cooling fluid conduits to pass cooling fluid through the antenna assembly.
2. A microwave applicator ( 14 ) according to claim 1 wherein the patch antenna comprises a planar inverted F antenna.
3. A microwave applicator ( 14 ) according to claim 1 wherein the patch antenna comprises an antenna trace ( 126 ).
4. A microwave applicator ( 14 ) according to claim 3 wherein the antenna trace ( 126 ) is formed in a spiral shape.
5. A microwave applicator ( 14 ) according to claim 4 wherein the spiral shape is a ¾ turn spiral.
6. A microwave applicator ( 14 ) according to claim 4 wherein the spiral shape is a rectangular spiral.
7. A microwave applicator ( 14 ) according to claim 1 wherein the patch antenna comprises the antenna trace ( 126 ), the antenna substrate ( 108 ) and a ground plane ( 129 ).
8. A microwave applicator ( 14 ) according to claim 1 wherein a fluid barrier ( 124 ) is positioned between the patch antenna and the cooling chamber ( 110 ).
9. A microwave applicator ( 14 ) according to claim 1 , wherein the antenna housing comprises a metal material configured to reduce stray radiation from the patch antenna.