Surgical strategies for peripheral nerve schwannoma based on the intraoperative neurophysiological monitoring

Abstract

Objective: To present our classification for peripheral nerve schwannomas as well as explore the surgical strategies and operative management of peripheral nerve schwannomas based on the intraoperative neurophysiological monitoring (INM) technique and to decrease the risk of postoperative neurological deficits in the management of these schwannomas. Materials and methods: A retrospective study was conducted on 92 cases of peripheral nerve microsurgery performed, using the INM technique. We also made the classification for peripheral nerve schwannomas into two types according to operative findings and proceeded corresponding surgical strategies. Results: All tumors were removed completely under microscopy and INM. Three patients developed residual neurological deficits at final follow-up. There were different results about temporary (18/92, 19.6%) and permanent (3/92, 3.3%) neurological deficits. The incidence of temporary and permanent neurological deficits in type II group was significantly higher than that in type I group (p < 0.01). The incidence of permanent neurological deficits in larger size tumors was significantly higher than that of smaller size (p < 0.01). Conclusions: We made the classification for peripheral nerve schwannomas according to operative findings based on INM that is helpful to our surgical strategies. Intracapsular enucleation was the preferred strategy with satisfactory results and low risk of nerve injury. The size and location of tumors seem to be related to the risk of fascicular injury. Keywords: Schwannoma, Peripheral nerve, Intraoperative neurophysiological monitoring, Surgical strategies, Classification, Intracapsular enucleation