Use of intraoperative neurophysiological monitoring during epiduroscopy as a safety measure

OBJECTIVE: In this study, we present the first 12 cases of the use of intraoperative neurophysiological monitoring (IONM) during therapeutic epiduroscopy in patients with clinical canal stenosis. METHODS: IESS was performed using two working instruments: an epidural balloon to dilate the epidural space without damaging the nerve structures (Resaloon®) and an element to perform flavotomy of the ligamentum flavum (Resaflex®). The procedure was performed at levels of the greatest stenosis, as detected using preoperative magnetic resonance imaging. RESULTS: Of the 12 cases that used IONM, 2 patients presented neurotonic activity in roots during ligamentum flavum ablation, 1 patient presented neurotonic activity while using Resaloon® in a root contralateral to the level at which the procedure was conducted, and other presented neurotonic activity in a root below the level at which the ligamentum flavum was ablated. In all cases, potentially harmful discharges stopped when the procedure was interrupted momentarily. CONCLUSIONS: Intraoperative neurophysiological monitoring detected alterations in surgical field and roots below and/or contralateral to the field, which disappeared with complete recovery after interrupting the procedure; this can avoid the possible prolonged or even permanent complications postoperatively. SIGNIFICANCE: Intraoperative neurophysiological monitoring during epiduroscopy is safe, thus optimizing surgical outcomes.