(A829) Highly Flexible Endoscope Made of Silicone for Endoscopy of the Cochlear

Introduction: A cochlear implant (CI) is a surgically implanted neuroprosthesis that provides sound perception. At present, during medical examinations of small tubes, e.g. the cochlear, glass fiber endoscopes are being used for optical imaging. Unfortunately, these glass fiber endoscopes are too rigid to be inserted into the cochlear. A soft and highly flexible endoscope would solve these problem.

Methods: The endoscope consists of a waveguide matrix, a lens system, a transparent protective
layer, a light isolating layer, and a layer system of high refractive index silicone and low
refractive index silicone. The examination area in the interior of the cochlear can be
illuminated by an external cold LED source whose light is guided in a layer due to total
reflection at the surface of another layer.

Results: The first silicone layers have been successfully manufactured, using a pressing and
curing tool. Currently, the 100 layer matrix is fabricated. The silicone lens has been
realized by placing drops on different substrates coated with a monolayer of halogen
silanes.
First measurements of 5 mm long waveguides show no detectable loss.

Conclusions: A soft endoscope made of silicone would be a great help in the medical diagnostic field
and could soon be part of the standard equipment of otorhinolaryngologists.
Furthermore, it could be used as a positioning help of the electrode in cochlear implant operations.