Browsing by Author "Strantzas, S"

Now showing 1 - 3 of 3

Open Access
Intraoperative neuromonitoring has a poor correlation with postoperative neurological deficits in noncord level adult deformity surgery
(Spine Journal, 2024-09-01) Sardar, Z; Swamy, G; Yoshida, G; Kelly, MP; Strantzas, S; Basu, S; Kwan, K; Smith, JS; Pellise, F; Gupta, MC; Jones, KE; Charalampidis, A; Rocos, B; Lewis, SJ; Lenke, LG
BACKGROUND CONTEXT: Intraoperative neuromonitoring (IONM) is routinely used during spinal deformity surgery. While it is highly effective at detecting spinal cord level changes, the utility for surgery at a noncord level is less known. The purpose of this study is to evaluate rates of new neural deficits relative to IONM alerts in noncord-level spinal deformity surgery. PURPOSE: In noncord-level spinal deformity surgery, postop neural deficits are incompletely associated with IONM alerts. The purpose of this study was to assess the efficacy of neuromonitoring in detecting and preventing neurological deficits. STUDY DESIGN/SETTING: Prospective, international, multicenter cohort. PATIENT SAMPLE: A total of 197 adult patients undergoing spinal deformity surgery at a noncord level. OUTCOME MEASURES: IONM changes defined as loss of amplitude>50% in SSEP or MEP from baseline or sustained EMG activity lasting>10 seconds were recorded. Postoperative new neurological deficits were recorded. Other outcomes measured were baseline demographics, radiographic alignment parameters, events leading to and following IONM alerts. METHODS: Twenty international centers prospectively documented IONM (EMG, SSEP and MEP), demographics, radiographic findings, and surgical events of patients (10-80 years) undergoing spinal deformity surgery. Inclusion criteria: neurologically intact, spinal deformity correction with major Cobb>80° or involving any osteotomy. IONM change was defined as loss of amplitude>50% in SSEP or MEP from baseline or sustained EMG activity lasting>10 seconds. RESULTS: Of 197 patients, 22 (11.2%) had an IONM alert. More patients were undergoing revision surgery during an alert compared to those with no alert (40.9% vs 18.9%, p = 0.026). IONM alerts did not correlate with coronal cobb angle, deformity angular ratio, sagittal vertical axis, or coronal vertical axis. There were a total of 26 alerts in 22 patients - 4 patients (18.2%) had 2 IONM alerts, while the other 18 (81.8%) had 1 alert. MEPs were affected in 21 of 26 alerts (80.8%) and 15 (71.4%) of those were recovered. Isolated MEP changes were seen in 16 of 26 alerts (61.5%). SSEPs were affected in 8 of 26 alerts (30.8%). Isolated SSEP changes were seen in 3 (11.5%). Lastly, EMGs were affected in only 2 (7.7%) and were isolated. Five of 21 MEP alerts (23.8%) were bilateral, whereas 16 (76.2%) were unilateral. The most frequent event preceding an MEP change was an osteotomy in 6 (28.6%) of 21 patients. The most frequent nonsurgical event preceding an MEP alert was technical in 5 (23.8%), followed by systemic (low blood pressure/anemia) and anesthetic in 3 patients each (14.3%). Thirty-three of 197 patients (16.8%) developed a new postop neural deficit. Of these patients, 24 (72.7%) had no IONM alert. In the presence of an IONM alert 9 of 22 (40.9%) had a new neural deficit. IONM alert and development of new neural deficit had a crude negative predictive value (NPV) of 86.1%. CONCLUSIONS: In noncord-level spinal deformity surgery, IONM alerts occurred in 11.2% of patients, with osteotomy being the most frequent preceding surgical event. A new postop neural deficit was observed in 16.8% of all patients, and in 41% of patients with a IONM alert. A surprisingly high 73% of postop neural deficits occurred in patients who did not have an alert. This highlights the need for further refinement of IONM techniques and alert criteria for noncord-level surgery. FDA Device/Drug Status: This abstract does not discuss or include any applicable devices or drugs.
Open Access
Rapid response during spinal deformity surgery can successfully save spinal cord function using intraoperative monitoring.
(Spine Journal, 2024-09-01) Theologis, AA; Gupta, MC; Swamy, G; Yoshida, G; Kelly, MP; Strantzas, S; Basu, S; Kwan, K; Smith, JS; Pellise, F; Kato, S; Sardar, Z; Ames, CP; Jones, KE; Charalampidis, A; Rocos, B; Lenke, LG; Lewis, SJ
This abstract contains content that is significantly similar to the authors' previously published abstract in the Global Spine Journal Rapid Fire. For access to the original publication, please visit the following DOI: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11086046/pdf/10.1177_21925682241239518.pdf.
Open Access
Responding to Intraoperative Neuromonitoring Changes During Pediatric Coronal Spinal Deformity Surgery
(Global Spine Journal, 2019-05-01) Lewis, SJ; Wong, IHY; Strantzas, S; Holmes, LM; Vreugdenhil, I; Bensky, H; Nielsen, CJ; Zeller, R; Lebel, DE; de Kleuver, M; Germscheid, N; Alanay, A; Berven, S; Cheung, KMC; Ito, M; Polly, DW; Shaffrey, CI; Qiu, Y; Lenke, LG
Study Design: Retrospective case study on prospectively collected data. Objectives: The purpose of this explorative study was: 1) to determine if patterns of spinal cord injury could be detected through intra-operative neuromonitoring (IONM) changes in pediatric patients undergoing spinal deformity corrections, 2) to identify if perfusion based or direct trauma causes of IONM changes could be distinguished, 3) to observe the effects of the interventions performed in response to these events, and 4) to attempt to identify different treatment algorithms for the different causes of IONM alerts. Methods: Prospectively collected neuromonitoring data in pre-established forms on consecutive pediatric patients undergoing coronal spinal deformity surgery at a single center was reviewed. Real-time data was collected on IONM alerts with >50% loss in signal. Patients with alerts were divided into 2 groups: unilateral changes (direct cord trauma), and bilateral MEP changes (cord perfusion deficits). Results: A total of 97 pediatric patients involving 71 females and 26 males with a mean age of 14.9 (11-18) years were included in this study. There were 39 alerts in 27 patients (27.8% overall incidence). All bilateral changes responded to a combination of transfusion, increasing blood pressure, and rod removal. Unilateral changes as a result of direct trauma, mainly during laminotomies for osteotomies, improved with removal of the causative agent. Following corrective actions in response to the alerts, all cases were completed as planned. Signal returned to near baseline in 20/27 patients at closure, with no new neurological deficits in this series. Conclusion: A high incidence of alerts occurred in this series of cases. Dividing IONM changes into perfusion-based vs direct trauma directed treatment to the offending cause, allowing for safe corrections of the deformities. Patients did not need to recover IONM signal to baseline to have a normal neurological examination.