Directional electrode devices with locating features

Abstract

Electrode devices having directional electrodes for use in deep brain stimulation or other uses. In one aspect, an electrode assembly comprises an elongate lead and a lead guide that are engageable with each other in a coaxial relationship. When the elongate lead and the lead guide are engaged with each other, the two components are rotationally fixed in relation to each other. In another aspect, an elongate lead comprises a radiologically-visible feature for indicating the orientation of the elongate lead. In yet another aspect, an electrode system is capable of determining the position and/or orientation of an electrode positioned within a body. In other aspects, methods for electrically stimulating a target site in the body are disclosed.

I/We claim: 
     
         1 . An elongate lead having a distal portion and longitudinal axis, the elongate lead comprising:
 at least one directional electrode disposed on the distal portion of the elongate lead, wherein each of the at least one directional electrode extends less than 360 degrees around the elongate lead; and   an orientation indicator positioned and aligned with an orientation of one of the at least one directional electrode.   
     
     
         2 . The elongate lead of  claim 1 , wherein the orientation indicator comprises a first portion and a second portion, wherein the first portion has a larger width than the second portion. 
     
     
         3 . The elongate lead of  claim 2 , wherein the first portion is proximal to the second portion. 
     
     
         4 . The elongate lead of  claim 1 , wherein the at least one directional electrode comprises two directional electrodes disposed at a same longitudinal position relative to the longitudinal axis of the elongate lead, wherein the two directional electrodes do not overlap with each other, wherein the orientation indictor is aligned with the orientation of only one of the two directional electrodes. 
     
     
         5 . The elongate lead of  claim 1 , further comprising at least one cylindrical electrode disposed on the distal portion of the elongate lead and extending 360 degrees around the elongate lead. 
     
     
         6 . The elongate lead of  claim 1 , wherein the at least one directional electrode comprises at least two directional electrodes disposed at different longitudinal positions relative to the longitudinal axis of the elongate lead, wherein the at least two directional electrodes do not overlap with each other, wherein the orientation indictor is aligned with the orientation of at least one of the at least two directional electrodes. 
     
     
         7 . The elongate lead of  claim 1 , wherein each of the at least one directional electrode extends no more than 120 degrees around the elongate lead. 
     
     
         8 . A method for implanting the elongate lead of  claim 1 , the method comprising:
 introducing the elongate lead into a patient using a lead guide; and   determining an orientation of the at least one directional electrode of the elongate lead using the orientation indicator.   
     
     
         9 . The method of  claim 8 , wherein the lead guide comprises a cannula. 
     
     
         10 . The method of  claim 8 , wherein the lead guide comprises a stylet. 
     
     
         11 . The method of  claim 8 , further comprising rotating the elongate lead to position the at least one directional electrode in a desired orientation. 
     
     
         12 . The method of  claim 8 , wherein the orientation indicator comprises a first portion and a second portion, wherein the first portion has a larger width than the second portion. 
     
     
         13 . The method of  claim 12 , wherein the first portion is proximal to the second portion. 
     
     
         14 . The method of  claim 8 , wherein the at least one directional electrode comprises two directional electrodes disposed at a same longitudinal position relative to the longitudinal axis of the elongate lead, wherein the two directional electrodes do not overlap with each other, wherein the orientation indictor is aligned with the orientation of only one of the two directional electrodes. 
     
     
         15 . The method of  claim 8 , wherein the elongate lead further comprises at least one cylindrical electrode disposed on the distal portion of the elongate lead and extending 360 degrees around the elongate lead. 
     
     
         16 . The method of  claim 8 , wherein the at least one directional electrode comprises at least two directional electrodes disposed at different longitudinal positions relative to the longitudinal axis of the elongate lead, wherein the at least two directional electrodes do not overlap with each other, wherein the orientation indictor is aligned with the orientation of at least one of the at least two directional electrodes. 
     
     
         17 . The method of  claim 8 , wherein each of the at least one directional electrode extends no more than 120 degrees around the elongate lead. 
     
     
         18 . An electrode assembly, comprising
 the elongate lead of  claim 1 ; and   a lead guide.   
     
     
         19 . The electrode assembly of  claim 18 , wherein the lead guide comprises a cannula. 
     
     
         20 . The electrode assembly of  claim 18 , wherein the lead guide comprises a stylet.