The sensory epithelium in the cochlea of the inner ear transduces sound energy into electrical signals, which are essential for a neurotransmitter release. Nevertheless, the in vivo behavior and correlation of the dynamics among each layer remains unclear. To assess the wide-range motion within a living organism, we develop multifrequency-swept optical coherence microscopic vibrometry (MS-OCMV). This method employed the wide-filed heterodyne interferometric vibration measurement technique, which can capture the full-field vibration amplitude and phase distributions with optical coherence microscopy (OCM). In this system, we newly introduced the broadband multifrequency supercontinuum (SC) as a light source. Manipulating the frequency interval of the multifrequency SC can determine the depth of the region of interest where the two-dimensional biological vibration distributed as well as to conduct 3D tomographic volumetric imaging. In this manuscript, we demonstrate the accuracy of two-dimensional surface vibration measurement and the underlying performance of 3D tomographic imaging. We report the measurement results of vibrational motions induced by sound stimuli on the sensory epithelium of a living guinea pig using MS-OCMV.
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