Development of Automated Tool for Electrode Array Insertion and its Study on Intracochlear Pressure

Cochlear implantation is the most successful approach for people with profound sensorineural hearing loss. Manual insertion of the electrode array may result in damaging the soft tissue structures and basilar membrane. An automated electrode array insertion device is reported to be less traumatic in cochlear implant surgery. Objectives: The present work develops a simple, reliable, and compact device for automatically inserting the electrode array during cochlear implantation and test the device to observe intracochlear pressure during simulated electrode insertion. Methods: The device actuates the electrode array by a roller mechanism. For testing the automated device, a straight cochlea having the dimension of the scala tympani and a model electrode is developed using a 3D printer. A pressure sensor is utilized to observe the pressure change at different insertional conditions. Results: The electrode is inserted into a prototype cochlea at different speeds without any pause, and it is noticed that the pressure is increased with the depth of insertion of the electrode irrespective of the speed of electrode insertion. The rate of pressure change is observed to be increased exponentially with the speed of insertion. Conclusion: At an insertion speed of 0.15 mm/s, the peak pressure is observed to be 133 Pa, which can be further evaluated in anatomical models for clinical scenarios.