Low-frequency harmonic acceleration in the evaluation of surgical treatment of Meniere's disease.

23 patients with classical findings of Meniere's disease and so diagnosed by a neurotologist were tested with harmonic acceleration. 7 of these patients were selected to receive endolymphatic-mastoid shunts for intractable vertigo and/or highly progressive fluctuant hearing loss. All 7 patients showed an increase in the impairment in their phase relationships at the lowest frequency (0.01Hz) following surgery which was considered to be secondary to the procedure. Later this phase lag returned to a level approaching normal. They also showed a definite decrease in the asymmetry (labyrinthine preponderance) of their nystagmic responses to acceleration.