Method of inserting an endosteal electrode

Abstract

An implantable tissue-stimulating device comprising an elongate electrode carrier member ( 11 ) having a plurality of electrodes thereon. The carrier member ( 11 ) is preformed from a resiliently flexible biocompatible silicone and extends from a distal end ( 12 ) to a stop member ( 13 ). The carrier member ( 11 ) is adapted for intracochlear but extraluminar insertion within the cochlea of an implantee. The placement of the carrier member ( 11 ) is designed to avoid any breach of the internal ducts of the cochlea ( 20 ), such as the scala tympani ( 24 ) and scala vestibuli ( 25 ) so that the normal hydrodynamic behavior of the cochlea ( 20 ) is not affected by any intrusive device. Use of the device in a system for masking or treating the symptoms of tinnitus is also described.

1 - 23 . (canceled) 
     
     
         24 . A method of inserting an endosteal electrode assembly comprising:
 providing the electrode assembly having a plurality of electrodes mounted on an elongate carrier member having a longitudinal axis, wherein the carrier member has a width that is at least twice as great as the thickness of the carrier member and an extension arm extending from the carrier member substantially perpendicular to the longitudinal axis;   accessing a crevice in a recipient's cochlea disposed outside of the cochlea's internal ducts;   gripping the extension arm;   guiding the carrier member into the crevice by the extension arm; and   sealing the crevice.   
     
     
         25 . The method of  claim 24 , wherein the extension arm is substantially planar and a planar surface of the extension arm is generally parallel to the longitudinal axis of the carrier member. 
     
     
         26 . The method of  claim 25 , wherein the extension arm is disposed at a proximal end of the carrier member. 
     
     
         27 . The method of  claim 24 , wherein the carrier member has a concave inner surface and a convex outer surface, and wherein said guiding the carrier member into the crevice by the extension arm comprises:
 guiding the carrier member into the crevice such that the inner surface faces toward the interior of the cochlea and the outer surface faces toward the endosteum of the cochlea.   
     
     
         28 . The method of  claim 24 , wherein said accessing the crevice in the recipient's cochlea disposed outside of the cochlea's internal ducts comprises:
 performing a fenestration to access a crevice of the cochlea between a spiral ligament and an endosteum of a lateral wall of the cochlea.   
     
     
         29 . The method of  claim 28 , wherein said gripping the extension arm comprises:
 gripping the extension arm with an insertion tool.   
     
     
         30 . The method of  claim 29 , wherein said guiding the carrier member into the crevice by the extension arm comprises:
 guiding the carrier member into the crevice by the extension arm using the insertion tool gripping the extension arm.   
     
     
         31 . A method of inserting an endosteal electrode assembly comprising:
 providing the electrode assembly having a plurality of electrodes mounted on an elongate carrier member having a longitudinal axis, wherein the carrier member has a width that is at least twice as great as the thickness of the carrier member and a stop member extending from the carrier member substantially perpendicular to the longitudinal axis;   accessing a crevice in the recipient's cochlea disposed outside of the cochlea's internal ducts;   gripping the stop member;   guiding the carrier member into the crevice by the stop member until the stop member resists further insertion of the carrier member; and   sealing the crevice.   
     
     
         32 . The method of  claim 31 , wherein said gripping the stop member comprises:
 gripping the stop member with an insertion tool.   
     
     
         33 . The method of  claim 32 , wherein said guiding the carrier member into the crevice by the stop member comprises:
 guiding the carrier member into the crevice by the stop member, via the insertion tool gripping the stop member, until the stop member resists further insertion of the carrier member.   
     
     
         34 . The method of  claim 31 , wherein the carrier member has a concave inner surface and a convex outer surface, and wherein said guiding the carrier member into the crevice by the stop member until the stop member resists further insertion of the carrier member comprises:
 guiding the carrier member into the crevice such that the inner surface faces toward the interior of the cochlea and the outer surface faces toward the endosteum of the cochlea.   
     
     
         35 . The method of  claim 34 , wherein at least one surface of each of the plurality of electrodes is adjacent to the inner surface. 
     
     
         36 . The method of  claim 31 , wherein the carrier member is resiliently flexible, and wherein said guiding the carrier member into the crevice by the stop member until the stop member resists further insertion of the carrier member comprises:
 guiding the carrier member into the crevice such that the carrier member follows the curvature of the endosteum of the cochlea along the basal turn.   
     
     
         37 . The method of  claim 31 , wherein the stop member has a length of between about 1.5 mm and 2.0 mm. 
     
     
         38 . A method of inserting an endosteal electrode assembly comprising:
 providing the electrode assembly having a plurality of electrodes mounted on an elongate carrier member having a longitudinal axis, wherein the carrier member has a width that is at least twice as great as the thickness of the carrier member and an extension arm extending from the carrier member substantially perpendicular to the longitudinal axis;   accessing a crevice in a recipient's cochlea disposed outside of the cochlea's internal ducts;   gripping the extension arm with an insertion tool;   guiding the carrier member into the crevice by the extension arm; and   sealing the crevice.   
     
     
         39 . The method of  claim 38 , wherein the extension arm is substantially planar and a planar surface of the extension arm is generally parallel to the longitudinal axis of the carrier member. 
     
     
         40 . The method of  claim 39 , wherein the extension arm is disposed at a proximal end of the carrier member. 
     
     
         41 . The method of  claim 38 , wherein the carrier member has a concave inner surface and a convex outer surface, and wherein said guiding the carrier member into the crevice by the extension arm comprises:
 guiding the carrier member into the crevice such that the inner surface faces toward the interior of the cochlea and the outer surface faces toward the endosteum of the cochlea.   
     
     
         42 . The method of  claim 41 , wherein at least one surface of each of the plurality of electrodes is adjacent to the inner surface. 
     
     
         43 . The method of  claim 38 , wherein the extension arm has a length of between about 1.5 mm and 2.0 mm.