Active positioning device for a perimodiolar cochlear electrode array

The authors report on an actuated positioning device for a cochlear prosthesis insertion procedure. The device consists of multiple high-aspect ratio fluidic actuator chambers integrated with a high-density silicon cochlear electrode array and manufactured in a tapered-helix form. Actuation chambers with cross-sectional sizes as small as 40 × 200 μm and lengths of 30 mm have been fabricated using flexible polymers. The device will allow for low-resistance basilar insertion of a stimulating electrode array into the cochlea providing for deep, perimodiolar position considered most beneficial for auditory nerve stimulation, while minimizing intracochlear trauma. Experimental measurements, FEA analysis, and modeling demonstrate a viable and appropriate actuation method for a cochlear implant procedure.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47852/1/542_2004_Article_376.pd

A high-density electrode array for a cochlear prosthesis

© 2003 IEEE. This paper reports a high-density cochlear electrode array integrated with an articulated backing device. Fabricated on a silicon substrate, the device offers stimulating sites on a pitch of 250 μm. The backing device is designed to facilitate a deeper cochlear insertion and position the sites closer to the targeted neural receptors. The device is the first step towards a high-density 128-site array integrated with closed-loop position-sensing and control. Monopolar and bipolar auditory thresholds in guinea pigs are 50 μA and 300 μA, respectively, with tissue compliance voltages at 500 μA of ∼1.0V. A 32-site four-channel active array designed as the forerunner of the 128-site array is also described