The Effects of Ultrasound on the Internal Ear: A Histological Investigation

Ultrasonics in Medicine

“…McLay, Flinn and Ormerod (1961). Brain et al (1960) report the general histological effects of ultrasonic irradiat'ions on the labyrinth of the cat, but they have no method of measuring the ultrasonic output of their treatment head, and so cannot relate the effect to the true intensity of radiation, t'he total energy delivered or absorbed, or to the distribution of intensit'y within the canal. They use a Federici generator a t a frequency of 1 AIc/s.…”

Four Years of Ultrasound in Meniere's Disease

“…In 1 case the palsy was transitory, with complete recovery on the seventh postoperative day. The paralysis was complete in 2 cases, requiring several months for recovery which was complicated with synkinesis or involuntary associated movements, indicating that the regenerating axons had split into several segments, in¬ nervating 2 or more muscle groups.7 Brain et al 8 have substantiated the thermal prob¬ lem, using a thermocouple in experiments with live cats. In 1960, James6 described a continuous irrigation technique, using saline at 37 C, at a rate of 50-80 ml.…”

“…The ultrasonic output is adjusted at the be¬ ginning of the procedure with a dosimeter and does not require adjustment by a physicist. 8. The apparatus is compact and readily trans¬ portable.…”

Vestibular Changes Following Ultrasonic Irradiation

“…Brain et al, 6 using the cat as the experimental animal, showed in their histological sections, destructive changes in the cochlea as well as in the vestibular apparatus. Their surgical approach was through the bulla and the middle ear.…”