Electrode with anti-spring back component

摘要

An implantable electrode arrangement for a cochlear implant system is described that prevents post-surgical retraction of the electrode. The arrangement includes at least one retraction limiter having an extracochlear portion located at a distal end of the extracochlear electrode lead and an intracochlear portion located at a proximal end of the intracochlear electrode array and made at least in part of a swellable material that expands in response to fluid contact. The intracochlear portion of the retraction limiter is adapted for deformation away from an outer surface of the array proximal end in response to exposure of the swellable material to perilymph fluid within the cochlea after surgical insertion of the electrode array into the implanted cochlea so as to form an anti-retraction projection preventing post-surgical retraction of the array proximal end back through the electrode opening in the outer surface of the implanted cochlea.

主权项

1. An implantable electrode arrangement for a cochlear implant system, comprising:
an extracochlear electrode lead for carrying one or more cochlear stimulation signals, the electrode lead having a lead proximal end couplable to an implanted signal processor, and a lead distal end configured to enter an electrode opening in the outer surface of a cochlea; an intracochlear electrode array for insertion into the cochlea, the electrode array having:
i. an array proximal end configured to be connected to the lead distal end at the electrode opening,ii. an array distal end configured for terminating within the cochlea, andiii. an outer surface with a plurality of stimulation contacts for applying the cochlear stimulation signals to target neural tissue within the cochlea; and at least one retraction limiter having an extracochlear portion located at the lead distal end and an intracochlear portion located at the array proximal end; wherein a distal end of the intracochlear portion of the at least one retraction limiter is fixedly attached to the outer surface of the array proximal end, and wherein the remainder of the intracochlear portion is separable from the outer surface of the array proximal end, whereby sliding of the extracochlear portion of the at least one retraction limiter over the lead distal end causes the separable part of the intracochlear portion to deform out away from the outer surface of the array proximal end to form an anti-retraction projection configured for preventing post-surgical retraction of the array proximal end back through the electrode opening.