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Distortion-product otoacoustic emissions are otoacoustic emissions evoked by two pure tones called primaries and proposed in order to provide a frequency specific investigation of the cochlea. This paper first reports complete input-output functions of distortion-product otoacoustic emissions for conventional audiometric frequencies in a population of 35 neonates without any risk for cochlear function. Distortion-product otoacoustic emissions could be useful, in association with evoked otoacoustic emissions and comportemental audiometry, to precisely evaluate the peripheral auditory system in infants and neonates.

The cochleovestibular tract is seldom involved by sarcoidosis (about 50 cases have been described since 1948). As a clinical expression of sarcoidosis, deafness is fluctuant in 50% of all cases, bilateral, and most often associated with facial palsy and uveitis, the vestibular reflexes being reduced. The histological studies demonstrate lesions at all levels from the cochlea to be brain stem, but the main mechanism is an infiltration of the arachnoid vessels. The prognosis of sarcoidosis deafness is usually poor in spite of corticosteroid therapy. This paper is illustrated by 3 cases observed in Avicenne Hospital.

Appreciating the difficulties in interpreting tonal audiograms using the classifications previously suggested, the authors, inspired by a paper by Wedenberg, have compared phonetic studies of phonemes and tonal audiograms. By this method they have obtained a simple audiometric pattern indicating both the degree of auditory loss and the rate of the curve. This is of value, from the point of view of classifying audiograms, for deciding on possible hearing-aids and for auditory education.