Abstract
Aim:
Recent guidelines have been published by the Association of Neurophysiological Scientists / British Society for Clinical Neurophysiology (ANS/BSCN) regarding the use of intra-operative neurophysiological monitoring (IOM) during spinal deformity procedures. We present our unit's experience with IOM and the compliance with national guidelines.
Method:
All patients undergoing intra-operative spinal cord monitoring during adult and paediatric spinal deformity surgery between Jan 2009 and Dec 2012 were prospectively followed. The use of somatosensory-evoked potentials (SSEPs) and motor-evoked potentials (MEPs) was recorded and monitoring outcomes were compared to post-operative clinical neurological outcomes. Compliance with the national ANS/BSCN guidelines was assessed.
Results:
333 patients were included in this study. IOM was successful in 312 patients (94%), with both MEPs and SSEPs obtained in 282 patients (85%). SEPs were achieved in 91% and MEPs in 87%. Aetiology was idiopathic in 199 cases, 53 neuromuscular, 28 degenerative, 16 congenital, 16 other. Nine patients had changes in IOM related to surgical activity; six had MEP changes only, three had MEPs and SSEPs changes. All but one of these changes returned to baseline following surgical action; the one remaining patient had a temporary postoperative neurological deficit. One patient had a post-operative single radiculopathy requiring surgical exploration, without change in initial IOM. Final IOM findings demonstrated a positive predictive value (PPV) of 1 and a negative predictive value (NPV) of 0.996.
Discussion:
IOM is essential during spinal deformity surgery and, using MEPs, has a high PPV and NPV. Our unit meets guidelines for MEP use and frequently meets guidelines for SSEP use.
Conflict Of Interest Statement: No conflict of interest.