First Experience With a New Thin Lateral Wall Electrode in Human Temporal Bones

Area of Science:

• Otolaryngology
• Biomedical Engineering
• Neurosurgery

Background:

• Modern cochlear implant electrode arrays require a balance between surgical ease, cochlear structure preservation, and stable positioning.
• Pediatric cochlear implant applications necessitate designs that prioritize minimal trauma and preservation of delicate cochlear structures.

Purpose of the Study:

• To evaluate a novel lateral wall electrode array, the SlimJ, developed by Advanced Bionics.
• To assess the surgical feasibility, positioning accuracy, and intracochlear trauma associated with the SlimJ electrode array in human temporal bones.

Main Methods:

• Ten fresh-frozen human temporal bones were implanted with the SlimJ electrode array via the round window.
• Postoperative cone beam computed tomography (CBCT) was used to assess electrode array location.
• Histological analysis was performed to evaluate intracochlear trauma on a 0-4 grade scale.

Main Results:

• The SlimJ electrode array demonstrated ease of insertion, with an average insertion depth of 432 degrees.
• Nine out of ten arrays were fully inserted, with no observed translocations in any of the cochleae.
• Slight contact with the basilar membrane was noted in 50% of cases, with no significant intracochlear trauma observed.

Conclusions:

• The SlimJ thin lateral wall electrode array consistently achieved scala tympani placement with excellent insertion success.
• The observed positioning and minimal trauma suggest the SlimJ array is a promising design for cochlear implantation.
• Further clinical investigation is warranted to evaluate hearing preservation and speech performance outcomes.