Multimodal Intraoperative Neuromonitoring Research Articles

Practice Pattern Variations in the Use of Neuromonitoring, Image Guidance, and Robotics for Lumbar Pedicle Screw Placement Based on a Nationwide Neurosurgery Survey

Lumbar pedicle screw placement surgery involves various assistive technologies, including fluoroscopic, stereotactic, or robotic navigation and intraoperative neuromonitoring (IONM). We aimed to discern neurosurgeons' preferences for screw placement techniques and IONM utility, while also considering the influence of experience. A survey was distributed to members of the Congress of Neurological Surgeons using REDCap software, collecting demographic data and querying preferred techniques for screw placement and IONM modalities. Opinions on IONM use during stereotactic or robotic navigation were also obtained. Responses were analyzed using Pearson's Chi Square and ANOVA tests via R software. Of 188 responses, 35.5% (n=67) reported 1-10 years of experience and 64.5% (n=121) reported ≥11 years. Less experienced neurosurgeons utilized stereotactic navigation more than those with greater experience (p < 0.001). Seasoned neurosurgeons utilized fluoroscopic guidance more often (p = 0.038). Less experienced neurosurgeons employed 1.69 (±0.11) techniques for their fixation surgeries compared to 1.50 (±0.0.8) for more experienced neurosurgeons. Robotic navigation utilization was low and comparable between the groups. Surgeons employing multiple techniques utilized t-EMG the most (62.1%, p = 0.024). No strong opinions emerged on the necessity of multi-modality IONM with robotic or stereotactic navigation. This national survey shows that stereotactic navigation is the predominant technique for pedicle screw placement among less experienced neurosurgeons, with seasoned neurosurgeons leaning towards fluoroscopic guidance. Robotic guidance was the least utilized technique with no observed difference based on experience. Neurosurgeons employing multiple techniques use IONM the most, compared with surgeons who only use stereotactic navigation and/or robotic guidance.

Transabdominal motor evoked potential neuromonitoring of lumbosacral spine surgery

BACKGROUND CONTEXTTranscranial Motor Evoked Potentials (TcMEPs) can improve intraoperative detection of femoral plexus and nerve root injury during lumbosacral spine surgery. However, even under ideal conditions, TcMEPs are not completely free of false-positive alerts due to the immobilizing effect of general anesthetics, especially in the proximal musculature. The application of transcutaneous stimulation to activate ventral nerve roots directly at the level of the conus medularis (bypassing the brain and spinal cord) has emerged as a method to potentially monitor the motor component of the femoral plexus and lumbosacral nerves free from the blunting effects of general anesthesia. PURPOSETo evaluate the reliability and efficacy of transabdominal motor evoked potentials (TaMEPs) compared to TcMEPs during lumbosacral spine procedures. DESIGNWe present the findings of a single-center 12-month retrospective experience of all lumbosacral spine surgeries utilizing multimodality intraoperative neuromonitoring (IONM) consisting of TcMEPs, TaMEPs, somatosensory evoked potentials (SSEPs), electromyography (EMG), and electroencephalography. PATIENT SAMPLETwo hundred and twenty patients having one, or a combination of lumbosacral spine procedures, including anterior lumbar interbody fusion (ALIF), lateral lumbar interbody fusion (LLIF), posterior spinal fusion (PSF), and/or transforaminal lumbar interbody fusion (TLIF). OUTCOME MEASURESIntraoperative neuromonitoring data was correlated to immediate postoperative neurologic examinations and chart review. METHODSBaseline reliability, false positive rate, true positive rate, false negative rate, area under the curve at baseline and at alerts, and detection of preoperative deficits of TcMEPs and TaMEPs were compared and analyzed for statistical significance. The relationship between transcutaneous stimulation voltage level and patient BMI was also examined. RESULTSTaMEPs were significantly more reliable than TcMEPs in all muscles except abductor hallucis. Of the 27 false positive alerts, 24 were TcMEPs alone, and 3 were TaMEPs alone. Of the 19 true positives, none were detected by TcMEPs alone, 3 were detected by TaMEPs alone (TcMEPs were not present), and the remaining 16 true positives involved TaMEPs and TcMEPs. TaMEPs had a significantly larger area under the curve (AUC) at baseline than TcMEPs in all muscles except abductor hallucis. The percent decrease in TcMEP and TaMEP AUC during LLIF alerts was not significantly different. Both TcMEPs and TaMEPs reflected three preexisting motor deficits. Patient BMI and TaMEP stimulation intensity were found to be moderately positively correlated. CONCLUSIONSThese findings demonstrate the high reliability and predictability of TaMEPs and the potential added value when TaMEPs are incorporated into multimodality IONM during lumbosacral spine surgery.

Prevention, Diagnosis, and Management of Intraoperative Spinal Cord Injury in the Setting of Spine Surgery: A Proposed Care Pathway.

This study is a mixed methods approach. Intraoperative spinal cord injury (ISCI) is a challenging complication in spine surgery. Intra-operative neuromonitoring (IONM) has been developed to detect changes in neural function. We report on the first multidisciplinary, international effort through AO Spine and the Praxis Spinal Cord Institute to develop a comprehensive guideline and care pathway for the prevention, diagnosis, and management of ISCI. Three literature reviews were registered on PROSPERO (CRD 42022298841) and performed according to PRISMA guidelines: (1) Definitions, frequency, and risk factors for ISCI, (2) Meta-analysis of the accuracy of IONM for diagnosis of ISCI, (3) Reported management approaches for ISCI and related events. The results were presented in a consensus session to decide the definition of IONM and recommendation of its use in high-risk cases. Based on a literature review of management strategies for ISCI, an intra-operative checklist and overall care pathway was developed by the study team. An operational definition and high-risk patient categories for ISCI were established. The reported incidence of deficits was documented to be higher in intramedullary tumour spine surgery. Multimodality IONM has a high sensitivity and specificity. A guideline recommendation of IONM to be employed for high-risk spine cases was made. The different sections of the intraoperative checklist include surgery, anaesthetic and neurophysiology. The care pathway includes steps (1) initial clinical assessment, (2) pre-operative planning, (3) surgical/anaesthetic planning, (4) intra-operative management, and (5) post-operative management. This is the first evidence based comprehensive guideline and care pathway for ISCI using the GRADE methodology. This will facilitate a reduction in the incidence of ISCI and improved outcomes from this complication. We welcome the wide implementation and validation of these guidelines and care pathways in prospective, multicentre studies.

A Cross-over study comparing the effects of Lactated Ringers vs. Normal Saline irrigation on Multi-Modality Intraoperative Neuromonitoring during skull base Surgery involving the facial nerve

A Cross-over study comparing the effects of Lactated Ringers vs. Normal Saline irrigation on Multi-Modality Intraoperative Neuromonitoring during skull base Surgery involving the facial nerve

Can NIRS be a surrogate indicator of elective shunt in carotid endarterectomy? A single-center observational retrospective study says no.

Neuromonitoring during carotid endarterectomy (CEA) under general anesthesia is desirable and may be useful for preventing brain ischemia, but the selection of the most appropriate method remains controversial. To determine the effectiveness of near infrared spectroscopy (NIRS) compared to multimodality intraoperative neuromonitoring (IONM) in indicating elective shunts and predicting postoperative neurological status. This is a retrospective observational study including 86 consecutive patients with CEA under general anesthesia. NIRS and multimodality IONM were performed during the procedure. IONM included electroencephalography (EEG), somatosensory evoked potentials (SSEPs) and transcranial motor-evoked potentials (TcMEPs). Sensitivity, specificity, and positive and negative predictive values (PPV and NPV) were calculated for each neuromonitoring modality. NIRS presented a sensitivity and a specificity for detecting brain ischemia of 77.7% and 89.6%, respectively (PPV = 46.6% and NPV = 97.2%). In contrast, a 100% sensitivity and specificity for multimodality IONM was determined (PPV and NPV = 100%). No significant difference (in demographical or clinical data) between "true positive" and "false-positive" patients was identified. Among the methods included in multimodality IONM, EEG showed the best results for predicting postoperative outcome after CEA (PPV and NPV=100%). NIRS is inferior to multimodality IONM in detecting brain ischemia and predicting postoperative neurological status during CEA under general anesthesia.

Neuromonitoring Guided Vessel Identification in Iatrogenic Arterial Injury During Meningioma Resection

ABSTRACT Neuromonitoring is commonly used in neurosurgery and allows intraoperative assessment of functional pathways in the brain during surgery. Monitoring alerts can guide surgical decision making in real-time allowing surgeons to mitigate or avoid potential iatrogenic injury and subsequent postoperative neurologic sequelae that may result from cerebral ischemia or malperfusion. Here we present a case of a patient undergoing a right pterional craniotomy for the resection of a tumor which crosses midline with multimodal intraoperative neuromonitoring including somatosensory evoked potentials, transcranial motor evoked potentials, and visual evoked potentials. During the final portion of tumor resection, arterial bleeding was noted of unknown origin shortly followed by loss of right lower extremity motor evoked potential recordings. Motor evoked potential recordings in the right upper, and left upper and lower extremities were stable, as well as all somatosensory evoked potentials and visual evoked potentials. This distinct pattern of right lower extremity motor-evoked potential loss suggested compromise of the contralateral anterior cerebral artery and guided the surgeons to a rapid intervention. The patient awoke from surgery with moderate postoperative weakness in the affected limb that resolved to preoperative status by postoperative day 2, and back to normal strength prior to three-month follow-up. In this case the neuromonitoring data suggested compromise to the contralateral anterior cerebral artery which guided the surgeons to investigate and identify the site of vascular injury. The present case reinforces the utility of neuromonitoring in emergent surgical situations to guide surgical decision making.

Intramedullary hemangioblastoma. Case report

Hemangioblastomas are benign tumors that develop from the vessels of the central nervous system and can be a manifestation of autosomal dominant von Hippel-Lindau disease. Statistically, they account for 1.5‒2.5% of all intracranial tumors and 2‒15% of spinal cord tumor lesions. There are very few publications on the intramedullary localization of these neoplasms.The patient, 45 years old, a serviceman, presented with complaints of headache, slight unsteadiness of gait, as well as slight weakness in the right extremities, more pronounced in the right upper extremity, periodic numbness of the upper extremities, which progressed and made further service impossible. On neurological examination: pupils D=S, light reflexes were brisk, eye movement was fully preserved and horizontal nystagmus. BNI - PS - I, BNI - NS - I. HB - I. GR - I. Swallowing and phonation were fully preserved. There was a slight hemiparesis on the right. Hemihypesthesia on the right was more prominent in the upper extremity. Ataxia of mixed genesis. Pelvic organs function was preserved. Periodic constipation for up to 7 days. Magnetic resonance imaging revealed a multifocal brain lesion. Supratentorially, a cystic mass measuring 2.60×2.12×2.14 cm with a solid component up to 1.5 cm in the diameter was detected in the of the thickened corpus callosum. Intramedullary cystic-solid lesion of the medulla oblongata extending to the cervical spinal cord with conventional dimensions of the solid component 1.76×1.23×1.57 cm and the cystic component was 1.52×1.62×1.22 cm. Magnetic resonance imaging of the cervicothoracic region of the spinal cord revealed significant hydromyelitic expansion of the central canal from the C2 level to the Th3 level (up to 10mm in the diameter). Endovascular embolization of the neoplasm with a liquid embolic agent (Phil) and following microsurgical en bloc tumor resection were performed.Hemangioblastomas with an intramedullary location are extremely difficult and risky for the surgical removal. The presence of a cystic component in the hemangioblastoma structure or perifocally gives a chance to remove such a neoplasm avoiding risk of functional deterioration. Preoperative endovascular obliteration of hemangioblastoma vascularity is considered as an effective measure, although it is associated with a risk of cerebral ischemia in corresponding brain structures. Another crucial issues of intramedullary hemangioblastoma surgery includes multimodal intraoperative neuromonitoring and maximum possible intraoperative magnification to minimize injury of adjacent brain structures. Present practice shows that multiple intramedullary cysts in the spinal cord commonly regressing after neoplasm removal and leads to improvement of neurological deficit within a relatively short period of time.Conclusions. Hemangioblastomas with intramedullary growth and perifocal cyst can be surgically removed with a good functional result and comprehensive approach includes preoperative selective angiography with endovascular embolization, multimodal intraoperative neuromonitoring and appropriate microsurgical technique.

Intraoperative neuromonitoring in non-idiopathic pediatric scoliosis operated with minimally fusionless procedure: A series of 290 patients

BackgroundOne of the worst complications of surgery for spinal deformity is postoperative neurological deficit. Multimodal intraoperative neuromonitoring (IONM) can be used to detect impending neurological injuries. This study aimed to analyze IONM in non-idiopathic scoliosis using a minimally invasive fusionless surgical technique. MethodsThis retrospective, single-center study was performed from 2014 to 2018. Patients with non-idiopathic scoliosis who underwent a minimally invasive fusionless procedure and had at least 2 years of follow-up were included. IONM was performed using a neurophysiological monitoring work station with somatosensory evoked potentials (SSEP) and neurogenic mixed evoked potentials (NMEP). ResultsA total of 290 patients were enrolled. The mean age at surgery was 12.9±3 years. The main etiology was central nervous system (CNS) disorders (n=139, 48%). Overall, 35 alerts (11%) in the SSEP and 10 (7%) in the NMEP occurred. There were two neurological deficits with total recovery after 6 months. There were no false negatives in either SSEP or NMEP, although there was one false positive in SSEP and two false positives for NMEP in the group without signal recovery. There was no significant relationship between the incidence of SSEP or NMEP loss and age, body mass index (BMI), number of rods used, upper instrumented vertebrae (p=0.36), lower instrumented vertebrae, or type of surgery. A preoperative greater Cobb angle was associated with a significantly higher risk of NMEP loss (p=0.02). In CNS patients, a higher BMI was associated with a statistically significant risk of NMEP loss (p=0.004). The use of a traction table was associated with a higher risk of signal loss (p=0.0005). ConclusionA preoperative higher Cobb angle and degree of correction were associated with a significant risk of NMEP loss. In CNS scoliosis, a higher BMI was associated with a significant risk of NMEP loss. The use of a traction table was associated with a higher risk of signal loss.

Tailored Approach and Multimodal Intraoperative Neuromonitoring in Cerebellopontine Angle Surgery.

The cerebellopontine angle (CPA) is a highly complex anatomical compartment consisting of numerous nervous and vascular structures that present mutual and intricate spatial relationships. CPA surgery represents, therefore, a constant challenge for neurosurgeons. Over the years, neurosurgeons have developed and refined several solutions with the aim of maximizing the surgical treatment effects while minimizing the invasiveness and risks for the patient. In this paper, we present our integrated approach to CPA surgery, describing its advantages in treating pathologies in this anatomical district. Our approach incorporates the use of technology, such as neuronavigation, along with advanced and multimodal intraoperative neuromonitoring (IONM) techniques, with the final goal of making this surgery safe and effective.

Intraoperative Neuromonitoring for Pediatric Pelvic Tumors.

BackgroundTumors of the pre-sacral and sacral spaces are a rare occurrence in children. Total tumor excision is required due to the significant risk of relapse in the event of partial surgery, but the surgical procedure may lead to postoperative problems such as urinary, sexual, and anorectal dysfunctions. Intraoperative neuromonitoring (IONM) has gained popularity in recent years as a strategy for preventing the onset of neurologic impairments by combining several neurophysiological techniques. The aim of our study is to describe the experience of Bambino Gesù Children’s Hospital in the use of IONM in pediatric pelvic surgery.Materials and MethodsThe data of patients treated for pelvic malignancies at Bambino Gesù Children’s Hospital from 2015 to 2019 were retrospectively collected. All patients were assessed from a neurologic and neuro-urologic point of view at different time-points (before and immediately after surgery, after 6 months, and 1-year follow-up). They were all monitored during a surgical procedure using multimodal IONM including transcranial motor evoked potentials (TcMEP), triggered-EMG (t-EMG), pudendal somatosensory evoked potentials (PSSEP), and bulbocavernosus reflex (BCR).ResultsDuring the study period, ten children underwent pelvic tumor removal at our Institution. In all cases, intraoperative neurophysiological recordings were stable and feasible. The preservation of neurophysiological response at the same intensity during surgical procedures correlated with no new deficits for all neurophysiological techniques.DiscussionAlthough the impact of the IONM on surgical strategies and clinical follow-up is unknown, this preliminary experience suggests that the appropriate use of several neurophysiological techniques can influence both the radicality of pelvic tumor removal and the neurological and urological outcome at clinical follow-up. Finally, because of the highly complex anatomy and inter-individual variances, this is especially useful in this type of surgery.

The Role of Intraoperative Neuromonitoring Modalities in Anterior Cervical Spine Surgery.

Background: Intraoperative neuromonitoring (IONM) is frequently used during spine surgery to mitigate the risk of neurological injuries. Yet, its role in anterior cervical spine surgery remains controversial. Without consensus on which anterior cervical spine surgeries would benefit the most from IONM, there is a lack of standardized guidelines for its use in such procedures. Purpose: We sought to assess the alerts generated by each IONM modality for 4 commonly performed anterior cervical spinal surgeries: anterior cervical diskectomy and fusion (ACDF), anterior cervical corpectomy and fusion (ACCF), cervical disk replacement (CDR), or anterior diskectomy. In doing so, we sought to determine which IONM modalities (electromyography [EMG], motor evoked potentials [MEP], and somatosensory evoked potentials [SSEP]) are associated with alert status when accounting for procedure characteristics (number of levels, operative level). Methods: We conducted a retrospective review of IONM data collected by Accurate Neuromonitoring, LLC, a company that supports spine surgeries conducted by 400 surgeons in 8 states, in an internally managed database from December 2009 to September 2018. The database was queried for patients who underwent ACCF, ACDF, anterior CDR, or anterior diskectomy in which at least 1 IONM modality was used. The IONM modalities and incidence of alerts were collected for each procedure. The search identified 8854 patients (average age, 50.6 years) who underwent ACCF (n = 209), ACDF (n = 8006), CDR (n = 423), and anterior diskectomy (n = 216) with at least 1 IONM modality. Results: Electromyography was used in 81.3% (n = 7203) of cases, MEP in 64.8% (n = 5735) of cases, and SSEP in 99.9% (n = 8844) of cases. Alerts were seen in 9.3% (n = 671), 0.5% (n = 30), and 2.7% (n = 241) of cases using EMG, MEP and SSEP, respectively. In ACDF, a significant difference was seen in EMG alerts based on the number of spinal levels involved, with 1-level ACDF (6.9%, n = 202) having a lower rate of alerts than 2-level (10.0%, n = 272), 3-level (15.2%, n = 104), and 4-level (23.4%, n = 15). Likewise, 2-level ACDF had a lower rate of alerts than 3-level and 4-level ACDF. A significant difference by operative level was noted in EMG use for single-level ACDF, with C2-C3 having a lower rate of use than other levels. Conclusions: This retrospective review of anterior cervical spinal surgeries performed with at least 1 IONM modality found that SSEP had the highest rate of use across procedure types, whereas MEP had the highest rate of nonuse. Future studies should focus on determining the most useful IONM modalities by procedure type and further explore the benefit of multimodal IONM in spine surgery.

Diagnostic Value of Multimodal Intraoperative Neuromonitoring by Combining Somatosensory-With Motor-Evoked Potential in Posterior Decompression Surgery for Thoracic Spinal Stenosis.

BackgroundIntraoperative neuromonitoring (IONM) has become an increasingly essential technique in spinal surgery. However, data on the diagnostic value of IONM in predicting impending postoperative neurological deficits (PONDs) for patients who underwent posterior decompression surgery for thoracic spinal stenosis (TSS) are limited. Furthermore, patients who are at the highest risk of waveform changes during the surgery remain unknown. Our purpose was to (1) assess the diagnostic accuracy of IONM by combining somatosensory-evoked potential (SSEP) with motor-evoked potential (MEP) in predicting PONDs for patients who underwent the surgery and (2) identify the independent risk factors correlated with IONM changes in our study population.MethodsA total of 326 consecutive patients who underwent the surgery were identified and analyzed. We collected the following data: (1) demographic and clinical data; (2) IONM data; and (3) outcome data such as details of PONDs, and recovery status (complete, partial, or no recovery) at the 12-month follow-up visit.ResultsIn total, 27 patients developed PONDs. However, 15, 6, and 6 patients achieved complete recovery, partial recovery, and no recovery, respectively, at the 12-month follow-up. SSEP or MEP change monitoring yielded better diagnostic efficacy in predicting PONDs as indicated by the increased sensitivity (96.30%) and area under the receiver operating characteristic (ROC) curve (AUC) value (0.91). Only one neurological deficit occurred without waveform changes. On multiple logistic regression analysis, the independent risk factors associated with waveform changes were as follows: preoperative moderate or severe neurological deficits (p = 0.002), operating in the upper- or middle-thoracic spinal level (p = 0.003), estimated blood loss (EBL) ≥ 400 ml (p < 0.001), duration of symptoms ≥ 3 months (p < 0.001), and impairment of gait (p = 0.001).ConclusionSomatosensory-evoked potential or MEP change is a highly sensitive and moderately specific indicator for predicting PONDs in posterior decompression surgery for TSS. The independent risks for IONM change were as follows: operated in upper- or middle-thoracic spinal level, presented with gait impairment, had massive blood loss, moderate or severe neurological deficits preoperatively, and had a longer duration of symptoms.Clinical Trial Registration[http://www.chictr.org.cn]; identifier [ChiCTR 200003 2155].

Can the Processed EEG Be Utilized as a Cerebral Ischemia Monitor during the Temporary Clip Application in Anterior Circulation Aneurysm Surgery?

AbstractPatients undergoing cerebral aneurysm clipping are at risk for cerebral ischemia. Ischemic tolerance varies among individuals. Hence, multimodal intraoperative neuromonitoring (IONM) is essential. IONM is not available in many centers. This case report highlights the utilization of processed electroencephalography (EEG) as a cerebral ischemia monitor during temporary clip application. Our patient underwent clipping of a ruptured anterior-communicating artery aneurysm. After the temporary clip applications on the right and left, A1 arterial segments led to a transient drop of somatosensory evoked potentials (SSEPs). At the same time, the frontal four-channel processed EEG showed a burst suppression (BS) pattern. Blood pressure augmentation and the removal of temporary clips helped restore the SSEP back to baseline and the disappearance of the BS pattern in processed EEG. During the steady state of anesthesia, the sudden appearance of the BS pattern in processed EEG can be attributed to clip-induced cerebral ischemia after ruling out other potential causes for BS.

Prediction of Post-operative Long-Term Outcome of the Motor Function by Multimodal Intraoperative Neuromonitoring With Transcranial Motor-Evoked Potential and Spinal Cord-Evoked Potential After Microsurgical Resection for Spinal Cord Tumors.

ObjectiveTo examine the effect of multimodal intraoperative neuromonitoring on the long-term outcome of motor function after microsurgical resection for spinal cord tumors.Materials and MethodsConsecutive fourteen patients with spinal tumors who were surgically treated at the University of Fukui Hospital between 2009 and 2020 [M:F = 10:4, ages ranging from 22 to 83 years (mean ± SD = 58 ± 21 years)] were included in this study. There were eight intra-axial tumors and six extra-axial tumors. There were four patients with hypertension, two patients with diabetes mellitus, and four patients with hyperlipidemia. Three patients were under antithrombotic medication, two were under steroid medication, four were current smokers, and four were current drinkers. Manual muscle test (MMT) of the upper and lower extremities of the patients was examined before surgery, 2 weeks after surgery, and at the final follow-up. The mean follow-up period was 38 ± 37 months. McCormick scores were examined before surgery and at the final follow-up. Microsurgical resection of the tumor was underwent through the posterior approach under transcranial motor-evoked potential (TcMEP) monitoring. The MEP of 46 extremities was recorded during the surgery. Gross total resection was achieved in 13 of 14 surgeries. Spinal cord-evoked potential (Sp-SCEP) monitoring was performed in eight of 14 patients.ResultsThe length of peritumoral edema was significantly longer in patients with deterioration of McCormick scores than in patients with preservation of McCormick scores (p = 0.0274). Sp-SCEP could not predict the deterioration. The ratio of MEP at the beginning of the surgery to that at the end of the surgery was the only significant negative factor that predicts deterioration of motor function of the extremity at the final follow-up (p = 0.0374, odds ratio [OR] 1.02E-05, 95% CI 9.13E+01–7.15E+18). A receiver operating characteristic (ROC) analysis revealed that the cutoff value of the ratio of MEP to predict the deterioration at the final follow-up was 0.23 (specificity 100%, specificity 88%, positive predictive value 100%, and negative predictive value 88%) to predict deterioration at the final follow-up.ConclusionsRatio MEP was the most significant negative factor to predict the deterioration of motor weakness at spinal tumor surgery. The setting of the cutoff value should be more strict as compared to the brain surgery and might be different depending on the institutions.

The Predictive Value of Multimodal Intraoperative Neuromonitoring Techniques for Periprocedural Preventive Interventions during Carotid Surgery (P15-10.006)

The Predictive Value of Multimodal Intraoperative Neuromonitoring Techniques for Periprocedural Preventive Interventions during Carotid Surgery (P15-10.006)

Long-term Neurologic Outcome After Spinal Ependymoma Resection With Multimodal Intraoperative Electrophysiological Recording: Cohort Study and Review of the Literature.

ObjectiveTo evaluate how multimodal intraoperative neuromonitoring (IONM) changes during spinal ependymoma (SE) resection correlate with long-term neuro-functional outcomes. MethodsA retrospective analysis of patients aged 18 years or older who underwent surgical resection for SE over a 10-year period was conducted. IONM changes were defined as sustained transcranial motor evoked potential (TcMEP) and/or somatosensory evoked potential (SSEP) signal decrease of 50% or greater from baseline. Primary endpoints were postoperative modified McCormick Neurologic Scale (MNS) scores at postoperative day (POD) < 2, 6 weeks, 1 year, and 2 years. Univariate and multivariate analyses were performed.ResultsTwenty-nine patients were identified. Average age was 44.2±15.4 years. Sixteen (55.2%) were male and 13 (44.8%) were female. Tumor location was 10 cervical-predominant (34.5%), 13 thoracic-predominant (44.8%), and 6 lumbar/conus-predominant (20.7%). A majority (69.0%) were World Health Organization grade 2 tumors. Twentyfour patients (82.8%) achieved gross total resection. Thirteen patients (44.8%) had a sustained documented IONM signal change and 10 (34.5%) had a TcMEP change with or without derangement in SSEP. At POD < 2, 6 weeks, 1 year, and 2 years, MNS was significantly higher for those when analyzing subgroups with either any sustained IONM or TcMEP±SSEP signal attenuation > 50% below baseline (all p<0.05). ConclusionSustained IONM derangements > 50% below baseline, particularly for TcMEP, are significantly associated with higher MNS postoperatively out to 2 years. Intraoperative and postoperative management of these patients warrant special consideration to limit neurologic morbidity.

Efficacy of D-Wave Monitoring Combined With the Transcranial Motor-Evoked Potentials in High-Risk Spinal Surgery: A Retrospective Multicenter Study of the Monitoring Committee of the Japanese Society for Spine Surgery and Related Research.

Retrospective multicenter cohort study. We aimed to clarify the efficacy of multimodal intraoperative neuromonitoring (IONM), especially in transcranial electrical stimulation of motor-evoked potentials (TES-MEPs) with spinal cord-evoked potentials after transcranial stimulation of the brain (D-wave) in the detection of reversible spinal cord injury in high-risk spinal surgery. We reviewed 1310 patients who underwent TES-MEPs during spinal surgery at 14 spine centers. We compared the monitoring results of TES-MEPs with D-wave vs TES-MEPs without D-wave in high-risk spinal surgery. There were 40 cases that used TES-MEPs with D-wave and 1270 cases that used TES-MEPs without D-wave. Before patients were matched, there were significant differences between groups in terms of sex and spinal disease category. Although there was no significant difference in the rescue rate between TES-MEPs with D-wave (2.0%) and TES-MEPs (2.5%), the false-positivity rate was significantly lower (0%) in the TES-MEPs-with-D-wave group. Using a one-to-one propensity score-matched analysis, 40 pairs of patients from the two groups were selected. Baseline characteristics did not significantly differ between the matched groups. In the score-matched analysis, one case (2.5%) in both groups was a case of rescue (P = 1), five (12.5%) cases in the TES-MEPs group were false positives, and there were no false positives in the TES-MEPs-with-D-wave group (P = .02). TES-MEPs with D-wave in high-risk spine surgeries did not affect rescue case rates. However, it helped reduce the false-positivity rate.

Abstract TP83: Benefit Of Multimodal Intraoperative Neuromonitoring Techniques During Carotid Procedures

Background: Carotid intervention is done for reduction of stroke risk. Intraoperative neuromonitoring (IOM), including electroencephalography (EEG), somatosensory evoked potential (SSEP), and cerebral oximetry/near-infrared spectroscopy (NIRS) may be used to guide operative decision-making and minimize the risk of perioperative complications. The utility of combining IOM methods is unclear. Therefore, we sought to investigate the value of multimodal IOM for carotid interventions. Methods: A retrospective review of all patients undergoing carotid intervention from January 1, 2012 to December 31, 2019 at a single academic medical center was done. Patients with acute stroke undergoing catheter directed thrombectomy were excluded. Data collected included: patient demographics, IOM parameters, surgical intervention with endpoints of 30-day post-operative complications. Surrogate end-points of IOM change and intraoperative hemodynamic interventions were also assessed. Efficacy and diagnostic value of each IOM modality alone, and in combination, were assessed using multivariable logistic regression. Results: 409 carotid interventions in 311 patients meeting inclusion criteria were identified. Patients were 63.3% male, 36.7% female, 83.4% white, 7.1% Hispanic, and 5.9% other. 162(39.6%) interventions were performed for ipsilateral symptoms including 111(27.1%) ipsilateral stroke, 91(22.3%) TIA. Use of a single versus multiple IOM modalities was not associated with a reduction in post-operative neurologic events. Changes in SSEP demonstrated a 2.97 odds ratio for predicting neurologic adverse events (AE), though this was not statistically significant. Conclusion: IOM changes were associated with an increase in AEs but IOM impact on intraoperative changes in surgical plans were infrequent. It is unclear whether IOM had a significant impact on procedural modifications though this may reflect an underpowered sample size. The low impact of IOM on outcome raises the question of cost-effectiveness of these techniques in reducing intraoperative complications from carotid procedures.

Waveform Changes of Multimodal Intraoperative Neuromonitoring in Adult Spinal Deformity Surgery

Waveform Changes of Multimodal Intraoperative Neuromonitoring in Adult Spinal Deformity Surgery

Outline and Benefits of Multi-Modality Intraoperative Neuromonitoring in Spine Surgery Explained with a Case Report

The major complication of any form of spinal surgery is neurological insult which can result in serious post-operative sensory or motor deficit. Intraoperative neuromonitoring has evolved to identify and help to avert these insults through real time assessment of the spinal cord function. This paper is to provide an outline of the major modalities utilised in Intraoperative neuromonitoring during spine surgery, how they help in identifying neurological insults and aid in reducing post operative deficits, all explained through a case report. Keywords : Neuromonitoring, Spine Surgery