Monitoring rate and predictability of intraoperative monitoring in patients with intradural extramedullary and epidural metastatic spinal tumors

• Published in: Spinal cord Vol. 55; no. 10; pp. 906 - 910
• Main Authors: Kang, H, Gwak, H S, Shin, S H, Woo, M K, Jeong, I H, Yoo, H, Kwon, J W, Lee, S H
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.10.2017; Nature Publishing Group
• Subjects: 692/308/409; 692/617/375/1922; 9/30; Adolescent; Adult; Aged; Aged, 80 and over; Anatomy; Anesthesia; Biomedical and Life Sciences; Biomedicine; Bone cancer; Epidural Neoplasms - physiopathology; Epidural Neoplasms - secondary; Epidural Neoplasms - surgery; Evoked potentials; Evoked Potentials, Motor; Evoked Potentials, Somatosensory; Feasibility Studies; Female; Human Physiology; Humans; Intraoperative Neurophysiological Monitoring - methods; Latency; Male; Metastases; Metastasis; Middle Aged; Monitoring; Motor evoked potentials; Movement Disorders - diagnosis; Movement Disorders - etiology; Movement Disorders - prevention & control; Neurochemistry; Neurological diseases; Neuropsychology; Neurosciences; Oncology; original-article; Patients; Postoperative Complications - diagnosis; Postoperative Complications - prevention & control; Retrospective Studies; Sensitivity; Sensitivity analysis; Sensitivity and Specificity; Spinal cancer; Spinal Cord Neoplasms - physiopathology; Spinal Cord Neoplasms - secondary; Spinal Cord Neoplasms - surgery; Treatment Outcome; Tumors; Young Adult
• ISSN: 1362-4393; 1476-5624
• DOI: 10.1038/sc.2017.43

Study design: Single-center retrospective study. Objectives: To evaluate the monitoring rate, sensitivity and specificity of intraoperative monitoring (IOM) during removal of intradural extramedullary (IDEM) or epidural metastatic spinal tumors. Also, to assess the efficacy of monitoring somatosensory-evoked potentials (SSEP) when motor-evoked potentials (MEP) are not measurable. Setting: The Neuro-Oncology Clinic, National Cancer Center, Korea. Methods: Patients ( n =101) with IDEM or epidural metastatic spinal tumors at the cord level underwent surgeries monitored with SSEP and/or MEP. The monitoring rate was defined as negative when MEP or SSEP could not be measured after reversal of the neuromuscular block under general anesthesia. Positive IOM changes included more than a 50% change in the MEP or SSEP amplitude and more than a 10% delay in SSEP latency. Results: MEP was measurable in 73% of patients. The MEP monitoring rate in patients with motor power grades of 3 or less was 39%, which was lower than that of SSEP (83%). The sensitivity, specificity and predictability of MEP for motor changes were 93, 90 and 91%, respectively. Conversely, the sensitivity, specificity and predictability of SSEP were 62, 97 and 89%, respectively. In patients in whom MEP was not measurable ( n =24), SSEP was monitored with a predictability of 83%. Conclusion: In cases of extramedullary spinal tumors, MEP shows a higher sensitivity than SSEP does. However, the monitoring rate of MEP in non-ambulatory patients was lower than that of SSEP. In those cases, SSEP can be useful to monitor for postoperative neurological deficits.