Impact of Preoperative Mapping and Intraoperative Neuromonitoring in Minimally Invasive Parafascicular Surgery for Deep-Seated Lesions

Abstract

Transsulcal tubular retractor-assisted minimally invasive parafascicular surgery changes the surgical strategy for deep-seated lesions by promoting a deficit-sparing approach. When integrated with preoperative brain mapping and intraoperative neuromonitoring (IONM), this approach may potentially improve patient outcomes. In this study, we assessed the impact of preoperative brain mapping and IONM in tubular retractor-assisted neuro-oncological surgery. This retrospective single-center cohort study included patients who underwent transsulcal tubular retractor-assisted minimally invasive parafascicular surgery for resection of deep-seated brain tumors from 2016 to 2022. The cohort was divided into 3 groups: group 1, no preoperative mapping or IONM (17 patients); group 2, IONM only (25 patients); group 3, both preoperative mapping and IONM (38 patients). We analyzed 80 patients (33 males and 47 females) with a median age of 46.5 years (range: 1-81 years). There was no significant difference in mean tumor volume (26.2 cm3 [range 1.07-97.4 cm3]; P= 0.740) and mean preoperative depth of the tumor (31 mm [range 3-65 mm], P= 0.449) between the groups. A higher proportion of high-grade gliomas and metastases was present within group 3 (P= 0.003). IONM was related to fewer motor (P= 0.041) and language (P= 0.032) deficits at hospital discharge. Preoperative mapping and IONM were also related to shorter length of stay (P= 0.008). Preoperative and intraoperative brain mapping and monitoring enhance transsulcal tubular retractor-assisted minimally invasive parafascicular surgery in neuro-oncology. Patients had a reduced length of stay and prolonged overall survival. IONM alone reduces postoperative neurological deficit.