Objective: To assess the efficacy of three intraoperative auditory monitoring techniques: auditory brainstem response (ABR), electrocochleography (ECoG), and direct eight nerve monitoring (DENM).
Study design: A retrospective review of the intraoperative recordings of ABR, ECoG, and DENM was performed.
Setting: A private, neurotologic practice.
Patients: Sixty-six patients with usable preoperative hearing underwent intraoperative auditory monitoring with ABR, ECoG, or DENM.
Interventions: Intraoperative auditory monitoring.
Main outcome measures: Postoperative pure-tone hearing threshold and word recognition scores.
Results: Of the 66 patients, 16 (24%) had postoperative serviceable hearing. Five (18%) of the 28 with ABR monitoring, 3 (17%) of the 18 with ECoG monitoring, and 8 (40%) of the 20 with DENM monitoring had serviceable hearing after surgery.
Conclusions: This study suggests that DENM may be more effective than ABR or ECoG, although the differences in hearing preservation rates are not statistically significant.