Human cochlear microanatomy–an electron microscopy and super-resolution structured illumination study and review

Abstract

Objective: Studies of the human cochlea are particularly challenging due its exceptional vulnerability and surrounding hard bone. Swift fixation and mild decalcification are necessary to maintain its structural integrity and preserve antigenicity. Such procedures may allow immunohistochemistry, gene analyses, and molecular imaging using super resolution illumination microscopy (SR-SIM) with nanometer resolution. Design: This presentation updates recent studies of the human cochlear microanatomy and immunohistochemistry by our laboratory, discussed in the context of current and past anatomic findings and the available literature. Results: Human studies are necessary, and there are intriguing discrepancies compared with experimental animal studies, highlighting that “men are not simply big mice.” The results may improve our understanding of the function of the human hearing organ, the diseases related to it, and how this better understanding can be extended to impact future treatment. Conclusion: The first human inner ear gene therapy trials are in progress, and the accessibility of human cochlear tissue for future stem cell treatment and gene transfer needs further elucidation.