Intraoperative Neuromonitoring for Tethered Cord Surgery in Infants: Challenges and Outcome

Objective: The aim of this study was to evaluate the efficacy and safety of intraoperative neuromonitoring (IONM) in surgery for tethered cord in infants. Materials and Methods: The study included 87 infants who underwent surgery for closed spinal dysraphism under IONM. Their preoperative neurological and urological statuses were compared with postoperative status clinically. The study design was prospective, and the study’s duration was from January 2011 to February 2020. IONM was performed (TcMEP and direct mapping) with an Xltek Protektor 32 IOM system, Natus Neurology/medical Inc., Middleton, USA. Statistical analysis in the form of χ2 is conducted using SPSS. Results: Overall, among 87 patients, clinical improvement was seen in 28 (28/29) patients with motor deficits, 17 (17/24) with bladder deficits, and 18 (18/24) with bowel deficits. The monitorability for motor and sphincter was 97.3% and 90.7%, respectively. The sensitivity of IONM in predicting new motor deficit was 100%, whereas the specificity was 100%. The negative predictive value of predicting motor deficit was 100%, with a diagnostic accuracy of 100%. There were no complications in this cohort related to the IONM. Conclusions: The study has highlighted that the use of IONM is sensitive in identifying motor injury in infants with reliable outcome correlation. Assessment, monitoring, and outcome correlation of bladder and sphincteric functions are a challenge in this cohort.

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Therapeutic methods for lipomyelomeningocele: literature review

10.5327/1516-3180.075 ◽

2021 ◽

Author(s):

Isabela Turino Lougon ◽

Taciana Maria Rolim Sampaio Oliveira ◽

Yan Ribeiro Francisco

Keyword(s):

Literature Review ◽

Neural Development ◽

Spinal Dysraphism ◽

Tethered Cord ◽

Relevant Information ◽

Neurological Deterioration ◽

Motor Deficits ◽

Wound Breakdown ◽

Pubmed Database ◽

Csf Leakage

Introduction: Lipomyelomeningocele is a congenital malformation in which the neural plate lies outside the spinal canal. Patients younger than 6 months of age are neurologically asymptomatic. However, if not diagnosed, the disease evolves with deterioration of bowel and bladder functions and, later, with motor deficits (paralysis) and loss of sensation. Accordingly, a literature review was developed about the therapeutic methods that enable a better quality of life and prevent or control disease progression. Objectives: This literature review aims to elucidate leading updates in the literature regarding the therapy for lipomyelomeningocele, a rare form of spinal dysraphism. Methods: Searches were performed in the LILACS e PubMed database and in the health descriptors (DeCs/MeSH), to establish the descriptors. Of the 6,292 articles found, 20 were selected, since only they presented relevant information about this topic. Results: From reading the articles, it was concluded that surgery is the recommended treatment for cases of lipomyelomeningocele. The main goal of surgery is to prevent future damage or further neurological deterioration and also to preserve or improve current neurological function. The widespread use of advanced prenatal ultrasonography can show neural development and suggest congenital malformations and progressive neurological deterioration. Conclusions: Although surgery is the best treatment, it may also be accompanied by outcomes such as meningitis, CSF leakage, neurological deterioration as a result of tethered cord or secondary to nerve injury, and incomplete healing or wound breakdown. Prenatal ultrasound is necessary to identify the malformation and support early diagnosis of lipomyelomeningocele and may open doors for future care and treatment.

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Feasibility of intraoperative motor evoked potential monitoring during tethered cord surgery in infants younger than 12 months

Child s Nervous System ◽

10.1007/s00381-021-05316-3 ◽

2021 ◽

Author(s):

Johannes Herta ◽

Erdem Yildiz ◽

Daniela Marhofer ◽

Thomas Czech ◽

Andrea Reinprecht ◽

...

Keyword(s):

Motor Evoked Potentials ◽

Motor Evoked Potential ◽

Tethered Cord ◽

Motor Deficit ◽

Motor Deficits ◽

Irreversible Loss ◽

Intravenous Anesthesia ◽

Evoked Potential Monitoring ◽

Transcranial Motor Evoked Potentials ◽

Clinical Records

Abstract Purpose Feasibility, reliability, and safety assessment of transcranial motor evoked potentials (MEPs) in infants less than 12 months of age. Methods A total of 22 patients with a mean age of 33 (range 13–49) weeks that underwent neurosurgery for tethered cord were investigated. Data from intraoperative MEPs, anesthesia protocols, and clinical records were reviewed. Anesthesia during surgery was maintained by total intravenous anesthesia (TIVA). Results MEPs were present in all patients for the upper extremities and in 21 out of 22 infants for the lower extremities. Mean baseline stimulation intensity was 101 ± 20 mA. If MEPs were present at the end of surgery, no new motor deficit occurred. In the only case of MEP loss, preoperative paresis was present, and high baseline intensity thresholds were needed. MEP monitoring did not lead to any complications. TIVA was maintained with an average propofol infusion rate of 123.5 ± 38.2 µg/kg/min and 0.46 ± 0.17 µg/kg/min for remifentanil. Conclusion In spinal cord release surgery, the use of intraoperative MEP monitoring is indicated regardless of the patient’s age. We could demonstrate the feasibility and safety of MEP monitoring in infants if an adequate anesthetic regimen is applied. More data is needed to verify whether an irreversible loss of robust MEPs leads to motor deficits in this young age group.

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Noninvasive Evaluation of Coronary Artery Bypass Grafts with 16-Slice Multidetector Computed Tomography

The Heart Surgery Forum ◽

10.1532/hsf98.20111075 ◽

2012 ◽

Vol 15 (1) ◽

pp. 12 ◽

Cited By ~ 1

Author(s):

Levent Sahiner ◽

Ali Oto ◽

Kudret Aytemir ◽

Tuncay Hazirolan ◽

Musturay Karcaaltincaba ◽

...

Keyword(s):

Computed Tomography ◽

Coronary Artery ◽

Diagnostic Accuracy ◽

Multidetector Computed Tomography ◽

Coronary Artery Bypass ◽

Predictive Value ◽

Artery Bypass ◽

Time Interval ◽

Mdct Angiography ◽

Sensitivity Specificity

Background: The aim of this study was to investigate the diagnostic accuracy of 16-slice multislice, multidetector computed tomography (MDCT) angiography for the evaluation of grafts in patients with coronary artery bypass grafting (CABG).Methods: Fifty-eight consecutive patients with CABG who underwent both MDCT and conventional invasive coronary angiography were included. The median time interval between the 2 procedures was 10 days (range, 1-32 days). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MDCT for the detection of occluded grafts were calculated. The accuracy of MDCT angiography for detecting significant stenoses in patent grafts and the evaluability of proximal and distal anastomoses were also investigated.Results: Optimal diagnostic images could not be obtained for only 3 (2%) of 153 grafts. Evaluation of the remaining 150 grafts revealed values for sensitivity, specificity, PPV, NPV, and diagnostic accuracy of the MDCT angiography procedure for the diagnosis of occluded grafts of 87%, 97%, 94%, 93%, and 92%, respectively. All of the proximal anastomoses were optimally visualized. In 4 (8%) of 50 patent arterial grafts, however, the distal anastomotic region could not be evaluated because of motion and surgical-clip artifacts. The accuracy of MDCT angiography for the detection of significant stenotic lesions was relatively low (the sensitivity, specificity, PPV, and NPV were 67%, 98%, 50%, and 99%, respectively). The number of significant lesions was insufficient to reach a reliable conclusion, however.Conclusion: Our study showed that MDCT angiography with 16-slice systems has acceptable diagnostic performance for the evaluation of coronary artery bypass graft patency.

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Introduction of intraoperative neuromonitoring does not necessarily improve overall long-term outcome in elective aneurysm clipping

Journal of Neurosurgery ◽

10.3171/2018.12.jns182177 ◽

2020 ◽

Vol 132 (4) ◽

pp. 1188-1196 ◽

Cited By ~ 2

Author(s):

Tobias Greve ◽

Veit M. Stoecklein ◽

Franziska Dorn ◽

Sophia Laskowski ◽

Niklas Thon ◽

...

Keyword(s):

Evoked Potentials ◽

Predictive Value ◽

Neurological Outcome ◽

Positive Impact ◽

Case Series ◽

Intraoperative Neuromonitoring ◽

Neurosurgical Procedures ◽

Long Term Outcome ◽

Unruptured Intracranial Aneurysms ◽

Significant Difference

OBJECTIVEIntraoperative neuromonitoring (IOM), particularly of somatosensory-evoked potentials (SSEPs) and motor-evoked potentials (MEPs), evolved as standard of care in a variety of neurosurgical procedures. Case series report a positive impact of IOM for elective microsurgical clipping of unruptured intracranial aneurysms (ECUIA), whereas systematic evaluation of its predictive value is lacking. Therefore, the authors analyzed the neurological outcome of patients undergoing ECUIA before and after IOM introduction to this procedure.METHODSThe dates of inclusion in the study were 2007–2014. In this period, ECUIA procedures before (n = 136, NIOM-group; 2007–2010) and after introduction of IOM (n = 138, IOM-group; 2011–2014) were included. The cutoff value for SSEP/MEP abnormality was chosen as an amplitude reduction ≥ 50%. SSEP/MEP changes were correlated with neurological outcome. IOM-undetectable deficits (bulbar, vision, ataxia) were not included in risk stratification.RESULTSThere was no significant difference in sex distribution, follow-up period, subarachnoid hemorrhage risk factors, aneurysm diameter, complexity, and location. Age was higher in the IOM-group (57 vs 54 years, p = 0.012). In the IOM group, there were 18 new postoperative deficits (13.0%, 5.8% permanent), 9 hemisyndromes, 2 comas, 4 bulbar symptoms, and 3 visual deficits. In the NIOM group there were 18 new deficits (13.2%; 7.3% permanent, including 7 hemisyndromes). The groups did not significantly differ in the number or nature of postoperative deficits, nor in their recovery rate. In the IOM group, SSEPs and MEPs were available in 99% of cases. Significant changes were noted in 18 cases, 4 of which exhibited postoperative hemisyndrome, and 1 suffered from prolonged comatose state (5 true-positive cases). Twelve patients showed no new detectable deficits (false positives), however 2 of these cases showed asymptomatic infarction. Five patients with new hemisyndrome and 1 comatose patient did not show significant SSEP/MEP alterations (false negatives). Overall sensitivity of SSEP/MEP monitoring was 45.5%, specificity 89.8%, positive predictive value 27.8%, and negative predictive value 95.0%.CONCLUSIONSThe assumed positive impact of introducing SSEP/MEP monitoring on overall neurological outcome in ECUIA did not reach significance. This study suggests that from a medicolegal point of view, IOM is not stringently required in all neurovascular procedures. However, future studies should carefully address high-risk patients with complex procedures who might benefit more clearly from IOM than others.

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Accuracy of MSCT Coronary Angiography with 64 Row CT Scanner—Facing the Facts

Clinical Medicine Insights Cardiology ◽

10.4137/cmc.s3864 ◽

2010 ◽

Vol 4 ◽

pp. CMC.S3864 ◽

Cited By ~ 3

Author(s):

M. Wehrschuetz ◽

E. Wehrschuetz ◽

H. Schuchlenz ◽

G. Schaffler

Keyword(s):

Coronary Artery Disease ◽

Coronary Artery ◽

Coronary Angiography ◽

Positive Predictive Value ◽

Diagnostic Accuracy ◽

Predictive Value ◽

Diagnostic Potential ◽

Coronary Artery Stenoses ◽

Artery Disease ◽

Msct Angiography

Improvements in multislice computed tomography (MSCT) angiography of the coronary vessels have enabled the minimally invasive detection of coronary artery stenoses, while quantitative coronary angiography (QCA) is the accepted reference standard for evaluation thereof. Sixteen-slice MSCT showed promising diagnostic accuracy in detecting coronary artery stenoses haemodynamically and the subsequent introduction of 64-slice scanners promised excellent and fast results for coronary artery studies. This prompted us to evaluate the diagnostic accuracy, sensitivity, specificity, and the negative und positive predictive value of 64-slice MSCT in the detection of haemodynamically significant coronary artery stenoses. Thirty-seven consecutive subjects with suspected coronary artery disease were evaluated with MSCT angiography and the results compared with QCA. All vessels were considered for the assessment of significant coronary artery stenosis (diameter reduction ≥ 50%). Thirteen patients (35%) were identified as having significant coronary artery stenoses on QCA with 6.3% (35/555) affected segments. None of the coronary segments were excluded from analysis. Overall sensitivity for classifying stenoses of 64-slice MSCT was 69%, specificity was 92%, positive predictive value was 38% and negative predictive value was 98%. The interobserver variability for detection of significant lesions had a κ-value of 0.43. Sixty-four-slice MSCT offers the diagnostic potential to detect coronary artery disease, to quantify haemodynamically significant coronary artery stenoses and to avoid unnecessary invasive coronary artery examinations.

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Long-term motor deficit in brain tumour surgery with preserved intra-operative motor-evoked potentials

Brain Communications ◽

10.1093/braincomms/fcaa226 ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Davide Giampiccolo ◽

Cristiano Parisi ◽

Pietro Meneghelli ◽

Vincenzo Tramontano ◽

Federica Basaldella ◽

...

Keyword(s):

Evoked Potentials ◽

Brain Tumour ◽

Evoked Potential ◽

Corticospinal Tract ◽

Motor Evoked Potentials ◽

Motor Evoked Potential ◽

Motor Deficit ◽

Motor Deficits ◽

Brain Tumour Surgery

Abstract Muscle motor-evoked potentials are commonly monitored during brain tumour surgery in motor areas, as these are assumed to reflect the integrity of descending motor pathways, including the corticospinal tract. However, while the loss of muscle motor-evoked potentials at the end of surgery is associated with long-term motor deficits (muscle motor-evoked potential-related deficits), there is increasing evidence that motor deficit can occur despite no change in muscle motor-evoked potentials (muscle motor-evoked potential-unrelated deficits), particularly after surgery of non-primary regions involved in motor control. In this study, we aimed to investigate the incidence of muscle motor-evoked potential-unrelated deficits and to identify the associated brain regions. We retrospectively reviewed 125 consecutive patients who underwent surgery for peri-Rolandic lesions using intra-operative neurophysiological monitoring. Intraoperative changes in muscle motor-evoked potentials were correlated with motor outcome, assessed by the Medical Research Council scale. We performed voxel–lesion–symptom mapping to identify which resected regions were associated with short- and long-term muscle motor-evoked potential-associated motor deficits. Muscle motor-evoked potentials reductions significantly predicted long-term motor deficits. However, in more than half of the patients who experienced long-term deficits (12/22 patients), no muscle motor-evoked potential reduction was reported during surgery. Lesion analysis showed that muscle motor-evoked potential-related long-term motor deficits were associated with direct or ischaemic damage to the corticospinal tract, whereas muscle motor-evoked potential-unrelated deficits occurred when supplementary motor areas were resected in conjunction with dorsal premotor regions and the anterior cingulate. Our results indicate that long-term motor deficits unrelated to the corticospinal tract can occur more often than currently reported. As these deficits cannot be predicted by muscle motor-evoked potentials, a combination of awake and/or novel asleep techniques other than muscle motor-evoked potentials monitoring should be implemented.

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Influence of lesion location on the accuracy of CT derived FFR: head-to-head comparison with invasive FFR

European Heart Journal ◽

10.1093/ehjci/ehaa946.0158 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

M Moshage ◽

S Smolka ◽

S Achenbach ◽

F Ammon ◽

P Ferstl ◽

...

Keyword(s):

Coronary Angiography ◽

Positive Predictive Value ◽

Diagnostic Accuracy ◽

Negative Predictive Value ◽

Predictive Value ◽

Invasive Coronary Angiography ◽

Roc Curve Analysis ◽

Jude Medical ◽

Lesion Location ◽

Distal Vessel

Abstract Background The accuracy of CT-derived FFR (FFRCT) has been repeatedly reported. However, the influence of lesion location on accuracy is unknown. Therefore, we evaluated the diagnostic accuracy of FFRCT to detect lesion-specific ischemia and determined the influence of lesion location (proximal vs. distal vessel segments) compared to invasively measured FFR in patients with suspected CAD. Methods A total of 136 vessels in which “Dual-Source”-CT coronary angiography had been performed due to suspected CAD and who were further referred for invasive coronary angiography with invasive FFR measurement within three months of the index CT examination were retrospectively identified and screened for inclusion in this analysis. Patients with either left main coronary artery stenoses, bifurcation or ostial stenoses were excluded. Invasive FFR was measured using a pressure wire (CERTUS®, St. Jude Medical, Minnesota, USA or Verrata®, Volcano, San Diego, USA). FFRCT was calculated using an on-site prototype (cFFR Version 3.0, Siemens Healthineers, Forchheim, Germany). All vessels were analyzed by an experienced observer blinded to the results of invasive FFR. Stenoses with invasively measured FFR ≤0.80 were classified as hemodynamically significant. We evaluated the diagnostic accuracy of FFRCT in proximal vs. non-proximal vessel segments. Proximal lesions included stenoses located in segment one, six, eleven and twelve. All other stenoses were categorized as distal lesions. Results Out of 136 coronary stenoses, 47 (35%) were located in proximal segments and 89 (65%) lesions were located in distal segments. Compared to invasive FFR, the sensitivity of FFRCT to correctly identify/exclude hemodynamically significant stenoses in proximal vessel segments was 93% (95% CI: 68–99.8%) and the specificity was 100% (95% CI: 89–100%), compared to a sensitivity of 72% (95% CI: 46.5–90%) and a specificity of 87% (95% CI: 77–94%) for FFRCT in distal lesions. The positive predictive value was 100% and the negative predictive value was 97% (95% CI: 82.8–99.5%) compared to a positive predictive value of 59% (95% CI: 42–93.9%) and a negative predictive value of 93% (95% CI: 85.4–96.3%) for proximal vs. distal vessel segment, respectively. This corresponds to an accuracy of 98% vs. 84%, respectively (p=0.02). ROC-Curve analysis showed a slightly higher – albeit non-significant – area under the curve for FFRCT to detect hemodynamic relevance in proximal lesions compared to distal lesions (AUC 0.95, p<0.001 vs. AUC: 0.86, p<0.001, respectively, p=0.2). Conclusion FFRCT obtained using an on-site prototype shows overall a high diagnostic accuracy for detecting lesions causing ischemia as compared to invasive FFR with a trend towards better diagnostic performance in proximal vessel segments. Funding Acknowledgement Type of funding source: None

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Motor Evoked Potential Warning Criteria in Supratentorial Surgery: A Scoping Review

Cancers ◽

10.3390/cancers13112803 ◽

2021 ◽

Vol 13 (11) ◽

pp. 2803

Author(s):

Evridiki Asimakidou ◽

Pablo Alvarez Abut ◽

Andreas Raabe ◽

Kathleen Seidel

Keyword(s):

Scoping Review ◽

Predictive Value ◽

Motor Evoked Potentials ◽

Motor Evoked Potential ◽

Critical Duration ◽

Motor Deficit ◽

Warning Sign ◽

Outcome Reporting ◽

Scoping Reviews ◽

Warning Criteria

During intraoperative monitoring of motor evoked potentials (MEP), heterogeneity across studies in terms of study populations, intraoperative settings, applied warning criteria, and outcome reporting exists. A scoping review of MEP warning criteria in supratentorial surgery was conducted in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR). Sixty-eight studies fulfilled the eligibility criteria. The most commonly used alarm criteria were MEP signal loss, which was always a major warning sign, followed by amplitude reduction and threshold elevation. Irreversible MEP alterations were associated with a higher number of transient and persisting motor deficits compared with the reversible changes. In almost all studies, specificity and Negative Predictive Value (NPV) were high, while in most of them, sensitivity and Positive Predictive Value (PPV) were rather low or modest. Thus, the absence of an irreversible alteration may reassure the neurosurgeon that the patient will not suffer a motor deficit in the short-term and long-term follow-up. Further, MEPs perform well as surrogate markers, and reversible MEP deteriorations after successful intervention indicate motor function preservation postoperatively. However, in future studies, a consensus regarding the definitions of MEP alteration, critical duration of alterations, and outcome reporting should be determined.

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Neurophysiologic Mapping of Thalamocortical Tract in Asleep Craniotomies: Promising Results From an Early Experience

Operative Neurosurgery ◽

10.1093/ons/opaa330 ◽

2020 ◽

Author(s):

Mirela V Simon ◽

Daniel K Lee ◽

Bryan D Choi ◽

Pratik A Talati ◽

Jimmy C Yang ◽

...

Keyword(s):

General Anesthesia ◽

Corticospinal Tract ◽

Sensory Function ◽

Motor Deficit ◽

Motor Deficits ◽

Central Sulcus ◽

Postcentral Gyrus ◽

Subcortical Stimulation ◽

Subcortical Mapping

Abstract BACKGROUND Subcortical mapping of the corticospinal tract has been extensively used during craniotomies under general anesthesia to achieve maximal resection while avoiding postoperative motor deficits. To our knowledge, similar methods to map the thalamocortical tract (TCT) have not yet been developed. OBJECTIVE To describe a neurophysiologic technique for TCT identification in 2 patients who underwent resection of frontoparietal lesions. METHODS The central sulcus (CS) was identified using the somatosensory evoked potentials (SSEP) phase reversal technique. Furthermore, monitoring of the cortical postcentral N20 and precentral P22 potentials was performed during resection. Subcortical electrical stimulation in the resection cavity was done using the multipulse train (case #1) and Penfield (case #2) techniques. RESULTS Subcortical stimulation within the postcentral gyrus (case #1) and in depth of the CS (case #2), resulted in a sudden drop in amplitudes in N20 (case #1) and P22 (case #2), respectively. In both patients, the potentials promptly recovered once the stimulation was stopped. These results led to redirection of the surgical plane with avoidance of damage of thalamocortical input to the primary somatosensory (case #1) and motor regions (case #2). At the end of the resection, there were no significant changes in the median SSEP. Both patients had no new long-term postoperative sensory or motor deficit. CONCLUSION This method allows identification of TCT in craniotomies under general anesthesia. Such input is essential not only for preservation of sensory function but also for feedback modulation of motor activity.

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