Intraluminal microneurography probe

Abstract

An intraluminal microneurography probe has a probe body that is configured to be introduced into an artery near an organ of a body without preventing the flow of blood through the artery. An expandable sense electrode and an expandable stimulation electrode are fixed to the probe body at one end of each electrode such that movement of the other end toward the fixed end causes the sense electrode to expand from the probe body toward a wall of the artery. A ground electrode is configured to couple to the body, and a plurality of electrical connections are operable to electrically couple the electrodes to electrical circuitry. The sense electrode is operable to measure sympathetic nerve activity in response to excitation of the stimulation electrode. An ablation element is located between the expandable sense electrode and expandable stimulation electrode, and is operable to ablate nerves proximate to the artery.

1 . An intraluminal microneurography probe, comprising:
 a probe body that is substantially cylindrical and having a diameter and a length that is perpendicular to the diameter, the probe configured to be introduced into an artery near an organ of a body without preventing the flow of blood through the artery;   an expandable sense electrode, fixed to the probe body at one end of the sense electrode and movable relative to the probe body at a second end of the sense electrode such that movement of the movable end toward the fixed end causes the sense electrode to expand from the probe body toward a wall of the artery;   an expandable stimulation electrode, fixed to the probe body at one end of the stimulation electrode and movable relative to the probe body at a second end of the stimulation electrode such that movement of the movable end toward the fixed end causes the sense electrode to expand from the probe body toward a wall of the artery;   a ground electrode configured to couple to the body;   a plurality of electrical connections operable to electrically couple at least the expandable sense electrode, expandable stimulation electrode, and ground electrode to electrical circuitry.   
     
     
         2 . The intraluminal microneurography probe of  claim 1 , wherein the sense electrode wire is equal to or smaller than 10 thousandths of an inch in a direction of nerve propagation. 
     
     
         3 . The intraluminal microneurography probe of  claim 1 , wherein at least one of the expandable sense electrode and the expandable stimulation electrode comprises an expandable mesh. 
     
     
         4 . The intraluminal microneurography probe of  claim 1 , wherein at least one of the expandable sense electrode and the expandable stimulation electrode comprises an expandable wire helix. 
     
     
         5 . The intraluminal microneurography probe of  claim 1 , wherein the diameter of the probe body is 2 mm or less. 
     
     
         6 . The intraluminal microneurography probe of  claim 1 , wherein the expandable sense electrode and the expandable stimulation electrode have fixed points on the probe body that are between two and four centimeters apart along the length of the probe body. 
     
     
         7 . The intraluminal microneurography probe of  claim 1 , wherein the ground electrode is configured on or near the probe body. 
     
     
         8 . The intraluminal microneurography probe of  claim 1 , further comprising a second ground electrode such that separate sense ground and stimulation ground electrodes are provided. 
     
     
         9 . The intraluminal microneurography probe of  claim 1 , wherein the separate sense ground and stimulation ground electrodes are coupled to one another via a low-pass filter. 
     
     
         10 . The intraluminal microneurography probe of  claim 1 , further comprising a sheath assembly operable to guide the probe into position within the artery. 
     
     
         11 . The intraluminal microneurography probe of  claim 10 , wherein the ground electrode is coupled to the sheath. 
     
     
         12 . The intraluminal microneurography probe of  claim 11 , further comprising a second ground electrode couplable to the body such that separate sense ground and stimulation ground electrodes are provided 
     
     
         13 . The intraluminal microneurography probe of  claim 11 , wherein the ground electrode coupled to the sheath and the second ground electrode couplable to the body are coupled to one another via a low-pass filter. 
     
     
         14 . The intraluminal microneurography probe of  claim 1 , further comprising a neural ablation element attached to the probe body. 
     
     
         15 . The intraluminal microneurography probe of  claim 14 , wherein the neural ablation element is attached to the probe body at a location between the expandable sense electrode and the expandable stimulation electrode. 
     
     
         16 . A method of characterizing nerve activity associated with a body organ, comprising:
 introduction of a probe into artery to a location proximate to the body organ;   expansion of an expandable sense electrode and an expandable stimulation electrode comprising a part of the probe to contact the artery wall while permitting blood flow around the expanded sense and stimulation electrodes;   excitation of the stimulation electrode using an electricity source coupled to the stimulation electrode; and   measurement of sympathetic nerve activity as a result of exciting the stimulation electrode using the expanded sense electrode.   
     
     
         17 . The method of characterizing nerve activity associated with a body organ of  claim 16 , further comprising ablation of nerves in the vicinity of the location proximate to the body organ. 
     
     
         18 . The method of characterizing nerve activity associated with a body organ of  claim 17 , where ablation is performed via an ablation element comprising a part of the probe. 
     
     
         19 . The method of characterizing nerve activity associated with a body organ of  claim 17 , further comprising re-excitation of the stimulation electrode using an electricity source coupled to the stimulation electrode, and re-measurement of sympathetic nerve activity as a result of exciting the stimulation electrode using the expanded sense electrode to confirm the effects of the ablation 
     
     
         20 . The method of characterizing nerve activity associated with a body organ of  claim 16 , wherein introduction of the probe into the artery comprises introducing the probe into the artery via a sheath.