Intraoperative facial nerve monitoring: a description of a unique system.

Intraoperative facial nerve monitoring has become an integral adjunct in facial nerve identification and preservation for patients undergoing cerebellopontine angle surgery. Since the first description of EMG monitoring of facial nerve activity intraoperatively, many systems have been developed. These systems often rely on unilateral monitoring of the facial nerve with auditory feedback to the surgeon, and it is difficult to distinguish between artifact and significant stimulation of the facial nerve. In this paper, we present the use of a bilateral, multialarm, facial nerve monitoring system that has multiple advantages over previous systems. Furthermore, we review our experience with this bilateral system, comparing a group of 50 monitored patients to a group of 50 unmonitored patients.