Comparison of tympanic membrane to promontory electrode recordings of electrocochleographic responses in patients with Menière's disease.

The purpose of the present study was to evaluate ECoG recordings obtained simultaneously from a transtympanic electrode and a tympanic membrane electrode in 26 patients with unilateral Meniere's disease. The ECoG recordings were examined quantitatively with regard to absolute amplitude of the summating potential and action potential. Recordings were examined qualitatively in terms of overall waveform quality and ease of component wave identification. All patients demonstrated a clear response with both electrodes. Although the transtympanic electrode resulted in the most robust responses in overall amplitude, the tympanic membrane electrode provided recordings equal to or, in most cases, superior to other noninvasive, extratympanic methods currently available. Furthermore, in our patient population, the likelihood of a positive (upward-going) summating potential was less for the tympanic membrane electrode recordings than for the TT electrode recordings. The major advantages of the TM electrode system are its unique method of stimulus delivery and its ease of application.