Intracochlear visualization: comparing established and novel endoscopy techniques.

HYPOTHESIS

Intracochlear visualization is achievable with chip-on-tip endoscopes-also called (digital) video endoscopy, videoscopy, electronic endoscopy, or endoscopy with distal chip/sensor/camera technology.

BACKGROUND

Recent advances in digital camera sensor sizes have significantly reduced the size of chip-on-tip endoscopes to sizes near that of the scala tympani opening up the possibility of intracochlear visualization.

METHODS

We compared the image quality of chip-on-tip cameras with commercially available rigid endoscopes (a.k.a. Hopkins rods) and commercially available fiber-optic scopes (sialendoscopes). Furthermore, we performed a feasibility study to elucidate the spatial constraints that future visualization technology must reach to allow intracochlear visualization.

RESULTS

Image resolution for chip-on-tip endoscopes ranks before fiberscopes and after Hopkins rods. The image quality depends further on illumination, which remains unresolved for chip-on-tip endoscopes for intracochlear visualization. The insertion depth of the currently available cameras allows up to 270 degrees of travel from the round window.

CONCLUSION

Visual guidance and inspection inside scala tympani is possible with a novel, small-sized digital camera endoscope. This may find clinical applicability for visual confirmation of anatomy during cochlear implantation.