Preliminary electrophysiological data after the obliteration of cochlear blood vessels by the action of a magnetic field on circulating iron particles.

In order to develop an experimental model for studying local disturbances of the inner ear microcirculation we conducted a series of experiments using small iron particles. Suspensions of iron were infused into the carotid artery of a tracheotomized guinea pig, after which a magnetic force was applied to the basal part of the cochlea. The cochlear microphonics were measured every 10 min over a frequency range from 200 Hz to 10 000 Hz. The amplitude of the cochlear microphonic decreased with this decrease dependent on the time after the application of the magnet. We then found that this amplitude was up to 30 dB less after 110 min. We were able to demonstrate histologically that the thrombosis induced by the iron particles blocks the circulation of the inner ear and results in a loss of its function.