Ag. Zeitouni et al., PROGNOSTIC-SIGNIFICANCE OF INTRAOPERATIVE FACIAL-NERVE STIMULUS THRESHOLDS, The American journal of otology, 18(4), 1997, pp. 494-497
Objective: Intraoperative facial nerve monitoring has reduced the inci
dence of facial nerve paralysis associated with acoustic neuroma surge
ry, but poor facial nerve outcomes continue to occur. Intraoperative p
rediction of facial nerve outcome would be advantageous in patient man
agement and counseling. This study seeks to evaluate intraoperative fa
cial nerve stimulus thresholds as a tool for predicting postoperative
facial nerve outcome. Study Design: This study is a prospective clinic
al study of the prognostic value of intraoperative stimulus thresholds
. Setting: The study was performed at a tertiary referral center. Pati
ents: There were 109 patients undergoing excision of acoustic neuromas
included in this study. Interventions: The minimum current required t
o stimulate the facial nerve at the brain stem was prospectively recor
ded after excision of the acoustic neuroma. Main Outcome Measures: Fac
ial nerve outcome was evaluated by the House-Brackmann grade. Results:
A statistically significant relationship was found between poor initi
al facial nerve outcome and higher stimulus thresholds. Long-term impa
ired facial function was also more common in the higher stimulus group
compared to that of the lower stimulus groups. Conclusions: Although
these findings suggest that intraoperative stimulus thresholds have pr
ognostic potential, other prognostic factors should also be considered
and additional research is needed.