Xie, Chong2024-05-202024-052024-04-19May 2024De Anda, Elsa Acosta. Re-designing Cochlear Implants: A Multi-Helix High Electrode Density Prototype. (2024). Masters thesis, Rice University. https://hdl.handle.net/1911/115919https://hdl.handle.net/1911/115919EMBARGO NOTE: This item is embargoed until 2026-05-01Sensorineural hearing loss (SNHL) is the most prevalent type of hearing impairment, with approximately 66,000 new cases reported annually in the United States alone. Cochlear implants (CIs) have proven to be a successful technology, offering the possibility of auditory restoration for individuals affected by profound SNHL. However, despite their success, the performance of these prostheses has not been able to decode the intricate patterns of sound perception close to a natural level, struggling under noise conditions and being incapable of providing pure tonal perception. Therefore, the quest to achieve a higher resolution and stimulation specificity remains an open challenge. Aiming to increase the number of effective frequency channels for stimulation, development initiatives have brought the number of electrodes from one, in the first FDA-approved prototype, up to 24 stimulation sites in the most modern commercial implant. However, it has been reported that with straight electrodes, even when 22 electrodes were in place, the effective number of stimulation channels was only up to 8, after this threshold the improvement in performance plateaus. This limitation is primarily attributed to channel shunting caused by the current dispersion within the highly conductive cochlear fluid. Consequently, mitigating current spread is crucial to avoid simultaneous excitation of neighboring frequencies and prevent media saturation. In response to these challenges, this research introduces a novel prototype, addressing the limitations of conventional cochlear implants by increasing the number of electrodes while simultaneously mitigating the current spread. The proposed design includes ten times more electrodes than any currently available commercial implant. By augmenting the electrode density while also promoting a close implant-neuron interface, the prototype aims to enhance the resolution and frequency specificity of cochlear implant stimulation. This innovative approach represents a promising advancement in cochlear implant technology, offering the potential for higher quality auditory restoration and improved outcomes for individuals suffering from sensorineural hearing loss.application/pdfengCopyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder.cochlear implantbiomedical devicesmicrofabricationThesis2024-05-20