Question 1: Does intraoperative facial nerve monitoring during vestibular schwannoma surgery lead to better long-term facial nerve function?
Target population: This recommendation applies to adult patients undergoing vestibular schwannoma surgery regardless of tumor characteristics.
Recommendation: Level 3: It is recommended that intraoperative facial nerve monitoring be routinely utilized during vestibular schwannoma surgery to improve long-term facial nerve function.
Question 2: Can intraoperative facial nerve monitoring be used to accurately predict favorable long-term facial nerve function after vestibular schwannoma surgery?
Target population: This recommendation applies to adult patients undergoing vestibular schwannoma surgery.
Recommendation: Level 3: Intraoperative facial nerve can be used to accurately predict favorable long-term facial nerve function after vestibular schwannoma surgery. Specifically, the presence of favorable testing reliably portends a good long-term facial nerve outcome. However, the absence of favorable testing in the setting of an anatomically intact facial nerve does not reliably predict poor long-term function and therefore cannot be used to direct decision-making regarding the need for early reinnervation procedures.
Question 3: Does an anatomically intact facial nerve with poor electromyogram (EMG) electrical responses during intraoperative testing reliably predict poor long-term facial nerve function?
Target population: This recommendation applies to adult patients undergoing vestibular schwannoma surgery.
Recommendation: Level 3: Poor intraoperative EMG electrical response of the facial nerve should not be used as a reliable predictor of poor long-term facial nerve function.
Question 4: Should intraoperative eighth cranial nerve monitoring be used during vestibular schwannoma surgery?
Target population: This recommendation applies to adult patients undergoing vestibular schwannoma surgery with measurable preoperative hearing levels and tumors smaller than 1.5 cm.
Recommendation: Level 3: Intraoperative eighth cranial nerve monitoring should be used during vestibular schwannoma surgery when hearing preservation is attempted.
Question 5: Is direct monitoring of the eighth cranial nerve superior to the use of far-field auditory brain stem responses?
Target population: This recommendation applies to adult patients undergoing vestibular schwannoma surgery with measurable preoperative hearing levels and tumors smaller than 1.5 cm.
Recommendation: Level 3: There is insufficient evidence to make a definitive recommendation. The full guideline can be found at: https://www.cns.org/guidelines/guidelines-manage-ment-patients-vestibular-schwannoma/chapter_4.
Keywords: Acoustic neuroma; Auditory brainstem response; Cranial nerve monitoring; EMG; Electrophysiology; Intraoperative cranial nerve monitoring; Vestibular schwannoma.
Copyright © 2017 by the Congress of Neurological Surgeons