Insertional depth-dependent intracochlear pressure changes in a model of cochlear implantation

Area of Science:

• Otorhinolaryngology
• Biomedical Engineering
• Neurosurgery

Background:

• Minimizing intracochlear trauma and preserving residual hearing are key goals in cochlear implantation (CI).
• Intracochlear pressure monitoring offers insights into electrode behavior within the cochlea.

Purpose of the Study:

• To investigate temporal intracochlear fluid pressure changes.
• To compare pressure variations under two distinct electrode insertion conditions.

Main Methods:

• Cochlear implantations performed using Advanced Bionics IJ® electrode in an artificial cochlear model.
• Constant insertion speed of 0.5 mm/s achieved via a linear actuator.
• Evaluation of amplitude pressure changes and pressure peaks during insertion.

Main Results:

• Homogenous increase in intracochlear pressure observed over time across all experiments.
• One-point-supported insertion showed significant reductions in amplitude variation and insertion depth over time.
• Two-point-supported insertion resulted in a significantly lower frequency of pressure peaks.

Conclusions:

• Intracochlear fluid pressure changes impact residual hearing preservation and should be minimized.
• Increased electrode stability at deeper insertions affects intracochlear fluid pressure amplitude.
• The two-point-supported insertion method demonstrates potential for reducing intracochlear trauma during CI procedures.