In Vivo Measurement of Ear Ossicle and Bony Wall Vibration by Sound Stimulation of Cartilage Conduction

The cartilage-conduction pathway was recently proposed as a third auditory pathway; however, middle-ear vibrations have not yet been investigated in vivo. We aimed to measure the ossicles and bone vibration upon stimulation with non-contact laser Doppler vibrometer. recruited adult patients normal ear structures who underwent cochlear implant surgery at our hospital between April 2020 December 2022. For sound input, transducer, custom-made by RION Corporation (Tokyo, Japan), fixed surface of tragus connected an audiometer regulate output. A posterior tympanotomy performed beam directed through cavity ossicles, promontory, wall external canal. Five participants (three men, mean age: 56.4 years) were included. hearing loss on operative side 96.3 dB HL one patient, that other off-scale. measured input 1 kHz 60 dB. observed all three structures, demonstrating existence pathways These results may help uncover mechanisms future.