Cochlear implant with multi-layer electrode

Inventors

TOURREL, Guillaume • MILENKOVIC, Léa • Tran, Yvette • Hourdet, Dominique • XU, Zuxiang

Assignees

Cochlear Ltd • Espci Paris

Abstract

A cochlear hearing aid system for providing electrical stimulation to auditory nerve fibers of a cochlea of a recipient of the cochlear hearing aid system is disclosed. The cochlear hearing aid system comprises a microphone configured to receive an acoustical signal and provide an audio signal based on the acoustical signal; a signal processor unit configured to receive the audio signal and process the audio signal; an electrode lead including a plurality of electrodes configured to stimulate the auditory nerve fibers based on the processed audio signal, wherein the electrode lead comprises: an electrode carrier maintaining the electrode contacts and wires, wherein the electrode carrier is made of silicone and is loaded by dexamethasone; a first layer (or sub-layers) of gelatin which is coated and chemically cross-linked selectively on a silicone outer surface of the electrode lead, wherein dexamethasone sodium phosphate is embedded in the first layer (or sub-layers); and a second layer of gelatin which is coated and physically cross-linked onto the first layer.

Core Innovation

The invention relates to a cochlear hearing aid system including an electrode lead having an electrode carrier loaded by dexamethasone. The electrode carrier comprises a silicone outer surface and maintains a plurality of electrode contacts and wires. A multi-layer electrode lead structure is formed to carry dexamethasone and to provide a defined drug-release profile over time.

A first layer of gelatin is coated and chemically cross-linked selectively on the silicone outer surface of the electrode carrier, with dexamethasone sodium phosphate embedded in the first layer. A second layer of gelatin is coated and physically cross-linked onto the first layer. The reported combination is stated to improve lubricity and to reduce insertion/friction force to mitigate cochlear trauma during electrode insertion.

The disclosed structure is further characterized by controlled temporal drug release, including short-term release for dexamethasone sodium phosphate over hours or days and long-term release over months or years. Gelatin swelling/degradation and layer formation concepts are presented in the disclosure, including formulation and structure details for gelatin types and layered geometries.

Claims Coverage

The partial claim set includes two independent claims (clm-00001 and clm-00011). Both independently recite the core three-part structure of a dexamethasone-loaded silicone electrode carrier with a chemically cross-linked gelatin first layer embedding dexamethasone sodium phosphate and a physically cross-linked gelatin second layer.

Across both independent claims, the inventive coverage centers on the same electrode-lead multi-layer architecture: dexamethasone-loaded silicone as the electrode carrier, a chemically cross-linked gelatin first layer embedding dexamethasone sodium phosphate, and a physically cross-linked gelatin second layer coated over the first layer.

Stated Advantages

Documented Applications