Imaging the auditory system: A new application of high-frequency ultrasound

This work describes an ex-vivo imaging study of the auditory system using high-frequency ultrasound. Tissue structures relevant to hearing disorders were imaged using a realistic in-vivo approach and a custom built 50 MHz annular-array imaging system. Images were generated of the middle ear and features of the tympanic membrane and ossicles could be visualized. Images were also generated of the inner ear where the basilar membrane could be visualized. The comparison of ultrasound images with ¿post-imaging¿ microscopic photos showed that features of the ossicles and the cochlea agreed with the ultrasound images. A 1 mm diameter Doppler probe has also been fabricated and pulsed-wave Doppler measurements were performed through the round window membrane on a fresh in-tact temporal bone as sound was applied to the ear canal.