OPTICAL ASSEMBLIES TO IMPROVE ENERGY COUPLING TO PRESSURE WAVE GENERATOR OF AN INTRAVASCULAR LITHOTRIPSY DEVICE
A catheter system ( 100 ) for treating a treatment site ( 106 ) within or adjacent to a vessel wall ( 108 ) or a heart valve includes an inflatable balloon ( 104 ), an optical fiber ( 122 ), and an energy source ( 124 ). The optical fiber ( 122 ) has a fiber proximal end ( 122 P), and a fiber distal end ( 122 D) positioned within the inflatable balloon ( 104 ). The optical fiber ( 122 ) is configured to receive an energy pulse so that the optical fiber ( 122 ) emits light energy in a direction away from the optical fiber ( 122 ) to generate a plasma pulse within the inflatable balloon ( 104 ). The optical fiber ( 122 ) can be tapered from the fiber proximal end ( 122 P) toward the fiber distal end ( 122 D). The energy source ( 124 ) in optical communication with the fiber proximal end ( 122 P) of the optical fiber ( 122 ), and can include a laser. The optical fiber ( 122 ) includes a first fiber member ( 250 ) and a second fiber member ( 258 ) that is coupled to the first fiber member ( 250 ). The first fiber member ( 250 ) can be fused to the second fiber member ( 258 ) in a fused region ( 256 ). The first fiber member ( 250 ) and the second fiber member ( 258 ) can be formed as a unitary structure. The catheter system ( 100 ) can also include a ferrule ( 248 ) that encircles the fused region ( 256 ).
1 . A catheter system for treating a treatment site within or adjacent to a vessel wall or a heart valve, the catheter system comprising:
an inflatable balloon;
an optical fiber having (i) a fiber proximal end, and (ii) a fiber distal end positioned within the inflatable balloon, the optical fiber being configured to receive an energy pulse so that the optical fiber emits light energy in a direction away from the optical fiber to generate a plasma pulse within the inflatable balloon, the optical fiber being tapered from the fiber proximal end to the fiber distal end; and
an energy source that is in optical communication with the fiber proximal end of the optical fiber.
2 . The catheter system of claim 1 wherein the optical fiber is tapered using a fusion splicer.
3 . The catheter system of claim 1 wherein the optical fiber is spliced using a core matched fiber.
4 . The catheter system of claim 1 wherein the optical fiber includes a first fiber member and a second fiber member that is coupled to the first fiber member.
5 . The catheter system of claim 4 wherein the second fiber member is positioned within the inflatable balloon.
6 . The catheter system of claim 4 wherein the first fiber member is fused to the second fiber member at a fused region.
7 . The catheter system of claim 6 further comprising a ferrule that encircles the fused region.
8 . The catheter system of claim 7 wherein the ferrule has an outer diameter of 1.25 mm LC ferrules.
9 . The catheter system of claim 7 wherein the ferrule has an outer diameter of 2.5 mm SC ferrules.
10 . The catheter system of claim 7 wherein the ferrule is formed from one of a plastic and a metal.
11 . The catheter system of claim 7 wherein the ferrule is configured to encircle only one optical fiber.
12 . The catheter system of claim 7 wherein the ferrule is one of a multi-fiber MT ferrule and an MTP ferrule.
13 . The catheter system of claim 4 wherein the first fiber member and the second fiber member are formed as a unitary structure.
14 . The catheter system of claim 4 wherein the first fiber member has a first fiber member distal region that is positioned outside of the inflatable balloon.
15 . The catheter system of claim 4 wherein the second fiber member has a second fiber member proximal region that is positioned outside of the inflatable balloon.
16 . The catheter system of claim 4 wherein the first fiber member includes an endcap.
17 . The catheter system of claim 1 wherein the optical fiber is tapered from a diameter of at least 150 μm down to a diameter of less than 120 μm.
18 . The catheter system of claim 1 wherein the optical fiber has a tapered portion with a tapered portion length of at least 2 mm.
19 . The catheter system of claim 1 wherein the energy source includes a laser.
20 . A catheter system for treating a treatment site within or adjacent to a vessel wall or heart valve, the catheter system comprising:
an inflatable balloon;
an optical fiber having (i) a fiber proximal end, and (ii) a fiber distal end positioned within the inflatable balloon, the optical fiber being configured to receive an energy pulse so that the optical fiber emits light energy in a direction away from the optical fiber to generate a plasma pulse within the inflatable balloon, the optical fiber having a first fiber member, a second fiber member, a fused region wherein the first fiber member is fused to the second fiber member, and a ferrule that substantially encircles at least the fused region; and
a laser that is in optical communication with the fiber proximal end of the optical fiber.