Abstract
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.