N. Shah1, A. Bansal2
1Suresh Brahmkumar Bhatt College of Physiotherapy, Physiotherapy, Ahmedabad, India, 2Chirayu Hospital, Spine Surgery, Ahmedabad, India
Background: Patients undergoing spine surgery are at risk of new neurological deficit (NND).Intra-operative Neuro-monitoring (IONM) is recommended during spine surgery for deformity Correction. Multimodal Neuro-monitoring comprise of Motor evoked Potential (MEPs) and somatosensory evoked potential (SSEPs). SSEPs monitor sensory tracts, gives high false positive and false negative alerts. While MEPs monitor motor pathways and MEPs are more sensitive to ischemia as compared to SSEPs.
Purpose: The purpose of the study is to determine diagnostic accuracy in terms of sensitivity, specificity, positive predictive value (PPV) and negative predictive value of motor evoked potential to report new neurological deficit in spine corrective surgery.
Methods: A retrospective data of 105 patients with spinal deformity who underwent corrective surgeries from April 2014 to July 2019 were collected. MEPs were used for monitoring during surgeries, which were monitored and interpreted by a trained physiotherapist. A Neurophysiological change i.e. alert was defined as 80% or more decrement in the amplitude in previously stable one or more MEPs. Data was studied for true positive, true negative, false positive, false negative, positive predictive value and negative predictive value. The definition of true positive included two subgroups, I) an alert which did not resolve despite the intervention and had a new neurological deficit, II) an alert resolved with the intervention and had no new neurological deficit. A calculation was made of sensitivity (true positive/true positive plus false negative) and specificity (true negative/true negative plus false positive).
Results: There were in total 33 alerts in 105 cases (31.42%).Out of 105 cases,26(27.76%) were True positives, 71 (67.61%) were true negatives, 07 (6.66%) were false positives and 1(0.95%) were false negatives. Sensitivity and specificity of MEPs were found to be 96% and 91% respectively. Positive predictive value and negative predictive value were found to be 78% and 98% respectively.
Conclusion(s): Motor evoked potential is an effective technique of monitoring the functional integrity and detect the new neurological deficit during corrective spine surgery of monitoring the spinal cord functional integrity during spine surgery. Thus MEPs should be used with effective communication between surgeon, anesthetist and monitoring team during corrective spine surgery.
Implications: MEPs are sensitive and specific in detecting NND in corrective spine surgery and should be further applied to other neurosurgeries.
Funding, acknowledgements: This work received no funding
We would like to thank Dr.Amit Jhala and Chirayu Orthopaedic and Spine Hospital, Ahmedabad, India
We would like to thank Dr.Amit Jhala and Chirayu Orthopaedic and Spine Hospital, Ahmedabad, India
Keywords: MEPs, spine corrective surgery, diagnostic accuracy
Topic: Neurology
Did this work require ethics approval? No
Institution: N/A
Committee: N/A
Reason: This is a retrospective data which was extracted from the previous surgeries performed.
All authors, affiliations and abstracts have been published as submitted.
