System and method of treating abnormal tissue in the human esophagus

Abstract

An ablation catheter system and method of use is provided to endoscopically access portions of the human esophagus experiencing undesired growth of columnar epithelium. The ablation catheter system and method includes controlled depth of ablation features and use of either radio frequency spectrum, non-ionizing ultraviolet radiation, warm fluid or microwave radiation, which may also be accompanied by improved sensitizer agents.

What is claimed is: 
     
         1 . A system for ablation of abnormal tissue from a human esophagus, comprising:
 an elongate shaft;   an ablation device comprising a highly compliant balloon coupled to a distal portion of the elongate shaft and expandable to a diameter for positioning in the esophagus; and   an inflation device for injecting an expansion medium into the balloon to expand the balloon; and   a pressure sensor for sensing pressure in an interior of the balloon,   wherein the inflation device is configured to control a pressure of the expansion medium in the balloon based on the pressure sensor.   
     
     
         2 . The system of  claim 1 , wherein the inflation device maintains the expansion medium in the balloon at a pressure of about 4 psig. 
     
     
         3 . The system of  claim 1 , wherein the inflation device maintains the expansion medium in the balloon at a pressure of about 7.5 psig. 
     
     
         4 . The system of  claim 1 , wherein the balloon is formed of an elastomer. 
     
     
         5 . The system of  claim 1 , wherein the balloon is expandable to a diameter conforming to an inner lumen of the esophagus at a target site. 
     
     
         6 . The system of  claim 5 , wherein the balloon has an expanded diameter between about 12 mm and about 25 mm. 
     
     
         7 . The system of  claim 1 , wherein the balloon is expandable to a diameter that will cause the esophagus to stretch. 
     
     
         8 . The system of  claim 1 , wherein the ablation device comprises a plurality of sets of RF electrodes associated with a circumference of the balloon. 
     
     
         9 . The system of  claim 8 , wherein the plurality of RF electrode sets are configured to provide power of about 15 Watts/sq.-com, about 20 Watts/sq.-cm, about 25 Watts/sq.-cm, or about 40 Watts/sq.-com. 
     
     
         10 . The system of  claim 8 , wherein the plurality of RF electrode sets at least partially extend around a circumference of the balloon. 
     
     
         11 . The system of  claim 8 , wherein the plurality of RF electrode sets are arranged in a pattern with a spacing between adjacent RF electrodes being no more than 2 mm, the pattern selected from the group consisting of bipolar rings, monopolar bands, bipolar axial interlaced finger electrodes, and combinations of the same. 
     
     
         12 . The system of  claim 8 , wherein the plurality of RF electrode sets form a first pattern, a second pattern, and a third pattern, the first pattern comprising bipolar rings with about 2 mm separation between adjacent rings. 
     
     
         13 . The system of  claim 8 , the RF electrode sets being arranged in a pattern, wherein a spacing of electrodes in an electrode pair is between about 0.3 mm and about 2 mm. 
     
     
         14 . The system of  claim 3 , wherein each of the RF electrode sets of the energy delivery device are arranged in a pattern of bipolar rings. 
     
     
         15 . The system of  claim 8 , wherein each of the RF electrode sets forms a pattern of monopolar rectangles with about 0.3 mm separation. 
     
     
         16 . The system of  claim 8 , wherein each of the RF electrode sets form a pattern of undulating electrodes with about 0.3 mm separation. 
     
     
         17 . The system of  claim 8 , further comprising steerable and directional control means.