Protecting role of facial nerve motor evoked potential monitoring in facial nerves during resection of cerebellopontine angle lesions / 中华神经医学杂志

ABSTRACT

Objective:To analyze the protecting role of facial nerve motor evoked potential (FNMEP) monitoring in facial nerves during the resection of cerebellopontine angle lesions.Methods:The clinical data and monitoring data of 83 patients with cerebellopontine angle lesions, accepted intraoperative facial nerve motor evoked potential (FNMEP) monitoring in our hospital from January 2019 to December 2019, were retrospectively investigated. Pre-surgical (opening dural), intraoperative and post-surgical (closing dural) FNMEP amplitudes were recorded. Relation of end (closing dura) to start (opening dura) amplitude ratio with facial nerve function grading at early-term (3 d after surgery) by House-Brackmann (H-B) grading was analyzed.Results:In these 83 patients, 75 patients (90.4%) achieved total tumor resection, and 8 patients (9.6%) achieved subtotal resection. Integrated anatomical preservation of facial nerves was achieved in all patients (100%); one (1.2%) was died for postoperatively delayed hemorrhage. Three d after surgery, facial nerve H-B grading I-II was noted in 62 patients, and the end to start amplitude ratio was 85.3% (66.8%, 93.4%); facial nerve H-B grading III was noted in 11 patients, and the end to start amplitude ratio was 45.6% (38.7%, 43.8%); facial nerve H-B grading IV was noted in 7 patients, and the end to start amplitude ratio was 23.1% (16.4%, 25.6%); facial nerve H-B grading V-VI was noted in 3 patients, and the end to start amplitude ratio was 6.7% (3.5%, 7.7%). There was a negative correlation between end to start FNMEP amplitude ratio and post-surgical early HB grading ( r s=-0.895, P=0.000). Conclusion:FNMEP is highly reliable in predicting early postoperative facial function during resection of cerebellopontine angle lesions, which can be a valid protection technique for facial nerve.