06304787 is referenced by 201 patents and cites 19 patents.

An implantable electrode array, adapted for insertion into a cochlea, provides a multiplicity of exposed electrode contacts, each having a shape, geometry, or makeup that aids in controlling the current flow and current density associated with the electrode contact as a function of position on the electrode contact. In one embodiment, the shape or geometry of the exposed electrode contact controls the contact surface of the electrode contact in a way that varies the current flow and current density as a function of surface area position on the electrode, thereby focusing most of the current to flow through the center of the electrode contact. In another embodiment, the electrode contact is coated with a dielectric or other material that controls the surface contact impedance as a function of distance from the center of the electrode, again focusing most of the current flow through the center of the electrode contact. In yet a further embodiment, the exposed electrode contact surface area is masked with an insulator to prevent conduction of current at various locations on the surface of the electrode contact. Separately, or in combination with any of the above embodiments, the exposed electrode contact surface and/or the entire electrode array may be coated with a selected substance or drug compound that diffuses into the tissue and liquids surrounding the electrode. Such substance or drug compound is selected to elicit a desired result, e.g., to inhibit fibrous tissue or bone growth in the vicinity of the electrode contacts; to promote healing of damaged tissue in the region of the electrode contacts, to prevent neural degeneration, or to promote neural regeneration.

Title
Cochlear electrode array having current-focusing and tissue-treating features
Application Number
9/375424
Publication Number
6304787 (B1)
Application Date
August 17, 1999
Publication Date
October 16, 2001
Inventor
Albert A Maltan
Stevenson Ranch
CA, US
William Vanbrooks Harrison
Valencia
CA, US
Janusz A Kuzma
Englewood
CO, US
Agent
Bryant R Gold
US
Assignee
Advanced Bionics Corporation
CA, US
IPC
A61N 1/36
View Original Source