[Changes of audio-vestibular parameters in experimental endolymphatic hydrops].

Endolymphatic hydrops were produced in twenty guinea pigs by obliteration of the endolymphatic sac. Auditory and vestibular functions were investigated before and after the obliteration. Our experimental data showed that: 1) the SPVN (sinusoidal pendular vestibular nystagmus) frequency decreased after the obliteration of the lymphatic sac; 2) the CAP response threshold to filtered clicks and the CAP response threshold to clicks were both elevated after obliteration of the endolymphatic sac; and 3) 2f1-f2 DPO (distortion product otoacoustic emissions) amplitudes, as induced by primary tones of adequate frequency and level rations, decreased as endolymphatic hydrops occurred.