Intraoperative Neuromonitoring for Tethered Cord Surgery in Infants: Challenges and Outcome

Abstract

Objective: The aim of this study was to evaluate the efficacy and safety of intraoperative neuromonitoring (IONM) in surgery for tethered cord in infants.

Materials and methods: The study included 87 infants who underwent surgery for closed spinal dysraphism under IONM. Their preoperative neurological and urological statuses were compared with postoperative status clinically. The study design was prospective, and the study's duration was from January 2011 to February 2020. IONM was performed (TcMEP and direct mapping) with an Xltek Protektor 32 IOM system, Natus Neurology/medical Inc., Middleton, USA. Statistical analysis in the form of χ2 is conducted using SPSS.

Results: Overall, among 87 patients, clinical improvement was seen in 28 (28/29) patients with motor deficits, 17 (17/24) with bladder deficits, and 18 (18/24) with bowel deficits. The monitorability for motor and sphincter was 97.3% and 90.7%, respectively. The sensitivity of IONM in predicting new motor deficit was 100%, whereas the specificity was 100%. The negative predictive value of predicting motor deficit was 100%, with a diagnostic accuracy of 100%. There were no complications in this cohort related to the IONM.

Conclusions: The study has highlighted that the use of IONM is sensitive in identifying motor injury in infants with reliable outcome correlation. Assessment, monitoring, and outcome correlation of bladder and sphincteric functions are a challenge in this cohort.

Keywords: Intraoperative neuromonitoring; Neurogenic bladder; Outcome; Tethered cord syndrome.