title: The efficacy of brainstem auditory evoked potentials in acoustic tumor surgery.
abstract: As the identification of patients with small acoustic neuromas and salvageable hearing increases, intraoperative auditory nerve monitoring has been used increasingly in an attempt to improve the hearing preservation rate. Far-field recordings obtained by brainstem auditory evoked potentials (BAEP), at times enhanced by electrocochleography, have become a standard method of intraoperative auditory nerve assessment. To evaluate the usefulness of this monitoring technique, the hearing preservation results of a series of unmonitored acoustic tumor removals were compared to a series of patients monitored via the standard brainstem auditory evoked potentials. With comparable average tumor sizes, 4 of 7 unmonitored patients had hearing preserved at preoperative levels compared to 4 of 9 monitored patients. Neither preoperative BAEP assessments nor absolute tumor size were predictive of hearing preservation. This report brings into question the effectiveness of far-field intraoperative BAEP monitoring during acoustic tumor resection and suggests that direct auditory nerve monitoring may be more appropriate.
authors.affiliation: Section of Otolaryngology, Yale University School of Medicine, New Haven, Conn 06510.
authors.forename: J F
authors.initials: JF
authors.lastname: Kveton
mesh_terms: D000328:Adult; D016057:Evoked Potentials, Auditory, Brain Stem; D006309:Hearing; D006801:Humans; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D009464:Neuroma, Acoustic / Q000503:physiopathology / Q000601:surgery*