Method and apparatus for applying energy to biological tissue including the use of tumescent tissue compression

Abstract

An electrode catheter is introduced into a hollow anatomical structure, such as a vein, and is positioned at a treatment site within the structure. Tumescent fluid is injected into the tissue surrounding the treatment site to produce tumescence of the surrounding tissue which then compresses the vein. The solution may include an anesthetic, and may further include a vasoconstrictive drug that shrinks blood vessels. The tumescent swelling in the surrounding tissue causes the hollow anatomical structure to become compressed, thereby exsanguinating the treatment site. Energy is applied by an electrode catheter in apposition with the vein wall to create a heating effect. The heating effect causes the hollow anatomical structure to become molded and durably assume the compressed dimensions caused by the tumescent technique. The electrode catheter can be moved within the structure so as to apply energy to a large section of the hollow anatomic structure. In a further aspect, the location of the electrodes is determined by impedance monitoring. Also, temperature sensors at the treatment site are averaged to determine the site temperature.

1 . A method of treating a vein, the method comprising:
 inserting an elongate member into a lumen of the vein and advancing the elongate member along the lumen to a treatment site;   a step for swelling the perivenal area at the treatment site with a fluid and thereby compressing the vein wall towards a distal end of the elongate member; and   a step for creating a thermal effect in the vein at the treatment site with the elongate member.   
     
     
         2 . The method of  claim 1 , wherein the step for creating a thermal effect comprises using radiofrequency current. 
     
     
         3 . The method of  claim 1 , wherein the step for creating a thermal effect comprises using light energy. 
     
     
         4 . The method of  claim 1 , wherein the step for creating a thermal effect comprises generating thermal energy with a resistive coil. 
     
     
         5 . The method of  claim 1 , further comprising moving the distal end of the elongate member along the vein lumen while creating the thermal effect. 
     
     
         6 . The method of  claim 1  further comprising:
 ceasing creating a thermal effect;   moving the distal end of the elongate member to a new treatment site along the vein lumen; and   a step for creating a thermal effect in the vein at the new treatment site with the elongate member.   
     
     
         7 . The method of  claim 6 , wherein the step for creating a thermal effect in the vein at the treatment site comprises generating thermal energy with a resistive coil. 
     
     
         8 . The method of  claim 1 , wherein the vein is located in a lower limb. 
     
     
         9 . The method of  claim 1 , wherein the elongate member comprises a catheter. 
     
     
         10 . The method of  claim 1 , wherein the elongate member comprises a fiber optic. 
     
     
         11 . The method of  claim 1 , wherein the fluid comprises tumescent fluid solution. 
     
     
         12 . The method of  claim 11 , wherein the step for swelling comprises administering the tumescent fluid solution into the perivenal area at the treatment site and thereby compressing the vein sufficiently to exsanguinate blood from the vein lumen at the treatment site. 
     
     
         13 . The method of  claim 1 , wherein the step for swelling includes compressing the vein to a reduced size around the elongate member.