Optical assemblies to improve energy coupling to pressure wave generator of an intravascular lithotripsy device

Abstract

A method for treating a treatment site (106) within or adjacent to a vessel wall (108) or heart valve includes tapering an optical fiber (122) from a fiber proximal end (122P) to a fiber distal end (122D); positioning the optical fiber (122) such that the fiber distal end (122D) is positioned within an inflatable balloon (104); coupling an energy source (124) in optical communication with the fiber proximal end (122P); and receiving an energy pulse from the energy source (124) into the fiber proximal end (122P) 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 method can further include coupling a first fiber member (250) to a second fiber member (258), which can include fusing the first fiber member (250) to the second fiber member (258) at a fused region (256); and encircling the fused region (256) with a ferrule (248).

1 . A method for treating a treatment site within or adjacent to a vessel wall or a heart valve, the method comprising the steps of:
 tapering an optical fiber from a fiber proximal end to a fiber distal end;   positioning the optical fiber such that the fiber distal end is positioned within an inflatable balloon;   coupling an energy source in optical communication with the fiber proximal end of the optical fiber; and   receiving an energy pulse from the energy source into the fiber proximal end of the optical fiber 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.   
     
     
         2 . The method of  claim 1  wherein the step of tapering includes tapering the optical fiber using a fusion splicer. 
     
     
         3 . The method of  claim 1  further comprising the step of splicing the optical fiber using a core matched fiber. 
     
     
         4 . The method of  claim 1  further comprising the step of coupling a first fiber member of the optical fiber to a second fiber member of the optical fiber. 
     
     
         5 . The method of  claim 4  wherein the step of positioning includes positioning the second fiber member within the inflatable balloon. 
     
     
         6 . The method of  claim 4  wherein the step of coupling the first fiber member of the optical fiber to the second fiber member of the optical fiber includes fusing the first fiber member to the second fiber member at a fused region. 
     
     
         7 . The method of  claim 6  further comprising the step of encircling the fused region with a ferrule. 
     
     
         8 . The method of  claim 7  wherein the step of encircling includes the ferrule having an outer diameter of 1.25 mm LC ferrules. 
     
     
         9 . The method of  claim 7  wherein the step of encircling includes the ferrule having an outer diameter of 2.5 mm SC ferrules. 
     
     
         10 . The method of  claim 7  wherein the step of encircling includes the ferrule being formed from one of a plastic and a metal. 
     
     
         11 . The method of  claim 7  wherein the step of encircling includes encircling only one optical fiber with the ferrule. 
     
     
         12 . The method of  claim 7  wherein the step of encircling includes the ferrule being one of a multi-fiber MT ferrule and an MTP ferrule. 
     
     
         13 . The method of  claim 4  wherein the step of coupling the first fiber member of the optical fiber to the second fiber member of the optical fiber includes forming the first fiber member and the second fiber member as a unitary structure. 
     
     
         14 . The method of  claim 4  wherein the step of positioning includes positioning a first fiber member distal region of the first fiber member outside of the inflatable balloon. 
     
     
         15 . The method of  claim 4  wherein the step of positioning includes positioning a second fiber member proximal region of the second fiber member outside of the inflatable balloon. 
     
     
         16 . The method of  claim 4  wherein the step of coupling the first fiber member of the optical fiber to the second fiber member of the optical fiber includes the first fiber member including an endcap. 
     
     
         17 . The method of  claim 1  wherein the step of tapering includes tapering the optical fiber from a diameter of at least 150 μm down to a diameter of less than 120 μm. 
     
     
         18 . The method of  claim 1  wherein the step of tapering includes the optical fiber having a tapered portion with a tapered portion length of at least 2 mm. 
     
     
         19 . The method of  claim 1  wherein the step of coupling the energy source includes the energy source including a laser. 
     
     
         20 . A method for treating a treatment site within or adjacent to a vessel wall or a heart valve, the method comprising the steps of:
 fusing a first fiber member of an optical fiber to a second fiber member of the optical fiber to define a fused region of the optical fiber, the optical fiber having a fiber proximal end and a fiber distal end;   substantially encircling at least the fused region of the optical fiber with a ferrule;   positioning the optical fiber such that the fiber distal end is positioned within an inflatable balloon;   coupling a laser in optical communication with the fiber proximal end of the optical fiber; and   receiving an energy pulse from the laser into the fiber proximal end of the optical fiber 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.