Nervous system -- Surgery and Nervous system -- Surveys

We thank Drs. Wilkinson and Kaufmann for their interest in our study (1) and their considered response to it. We thank them for highlighting the Canadian Association of Neurophysiological Monitoring [...]

To the Editor.-- After reading the noteworthy Zeskind and Stephens (1) study of the effects of in utero exposure to selective serotonin reuptake inhibitors (SSRIs) on neonates, it is likely [...]

Surgical equipment and supplies -- Usage, Surgical equipment and supplies -- Observations, Electromyography -- Usage, Chest -- Muscles, and Chest -- Health aspects

Pedicle screw-based constructs provide a stronger basis for spinal instrumentation and fusion than hooks. Placement of the screws within the pedicles is a technically challenging procedure. The orientation of the [...]

The article Is the new ASNM intraoperative neuromonitoring supervision "guideline" a trustworthy guideline? A commentary, written by Stanley A. Skinner, Elif Ilgaz Aydinlar, Lawrence F. Borges, Bob S. Carter, Bradford L. Currier, Vedran Deletis, Charles Dong, John Paul Dormans, Gea Drost, Isabel Fernandez‑Conejero, E. Matthew Hoffman, Robert N. Holdefer, Paulo Andre Teixeira Kimaid, Antoun Koht, Karl F. Kothbauer, David B. MacDonald, John J. McAuliffe III, David E. Morledge, Susan H. Morris, Jonathan Norton, Klaus Novak, Kyung Seok Park, Joseph H. Perra, Julian Prell, David M. Rippe, Francesco Sala, Daniel M. Schwartz, Martín J. Segura, Kathleen Seidel, Christoph Seubert, Mirela V. Simon, Francisco Soto, Jeffrey A. Strommen, Andrea Szelenyi, Armando Tello, Sedat Ulkatan, Javier Urriza and Marshall Wilkinson, was originally published electronically on the publisher's internet portal (currently SpringerLink) on 05 January 2019 without open access. With the author(s)' decision to opt for Open Choice the copyright of the article changed on 30 January 2019 to © The Author(s) 2019 and the article is forthwith distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits use, duplication, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made. The original article has been corrected.

Humans, Monitoring, Intraoperative, Thyroidectomy, and Intraoperative Neurophysiological Monitoring

Study Design: Retrospective review of results from a prospectively collected Canadian cohort in comparison to published literature.
Objectives: (1) To investigate whether patients in a universal health care system have different outcomes than those in a multitier health care system in surgical management of degenerative spondylolisthesis (DS). (2) To identify independent factors predictive of outcome in surgical DS patients.
Summary Of Background Data: Canada has a national health insurance program with unique properties. It is a single-payer system, coverage is universal, and access to specialist care requires referral by the primary care physician. The United States on the other hand is a multitier public/private payer system with more rapid access for insured patients to specialist care.
Methods: Surgical DS patients treated between 2013 and 2016 in Canada were identified through the Canadian Spine Outcome Research Network (CSORN) database, a national registry that prospectively enrolls consecutive patients with spinal pathology from 16 tertiary care academic hospitals. This population was compared with the surgical DS arm of patients treated in the Spine Patients Outcome Research Trial (SPORT) study. We compared baseline demographics, spine-related, and health-related quality of life (HRQOL) outcomes at 3 months and 1 year. Multivariate analysis was used to identify factors predictive of outcome in surgical DS patients.
Results: The CSORN cohort of 213 patients was compared with the SPORT cohort of 248 patients. Patients in the CSORN cohort were younger (mean age 60.1 vs. 65.2; p<.001), comprised fewer females (60.1% vs. 67.7%; p=.09), and had a higher proportion of smokers (23.3% vs. 8.9%; p<.001). The SPORT cohort had more patients receiving compensation (14.6% vs. 7.7%; p<.001). The CSORN cohort consisted of patients with slightly greater baseline disability (Oswestry disability index scores: 47.7 vs. 44.0; p=.008) and had more patients with symptom duration of greater than 6 months (93.7% vs. 62.1%; p<.001). The CSORN cohort showed greater satisfaction with surgical results at 3 months (91.1% vs. 66.1% somewhat or very satisfied; p<.01) and 1 year (88.2% vs. 71.0%, p<.01). Improvements in back and leg pain were similar comparing the two cohorts. On multivariate analysis, duration of symptoms, treatment group (CSORN vs. SPORT) or insurance type (public/Medicare/Medicaid vs. Private/Employer) predicted higher level of postoperative satisfaction. Baseline depression was also associated with worse Oswestry disability index at 1-year postoperative follow-up in both cohorts.
Conclusions: Surgical DS patients treated in Canada (CSORN cohort) reported higher levels of satisfaction than those treated in the United States (SPORT cohort) despite similar to slightly worse baseline HRQOL measures. Symptom duration and insurance type appeared to impact satisfaction levels. Improvements in other patient-reported health-related quality of life measures were similar between the cohorts.
(Copyright © 2019. Published by Elsevier Inc.)

Introduction: Odontoid fractures in young children are rare. Most authors advocate for closed reduction and external stabilization as first line treatment. Unlike adults, young children are much less amenable to an awake reduction for real-time assessment of neurological function. We used spinal cord monitoring, as used in spine surgery, to assess the function of the spinal cord during the closed reduction in our 31-month-old patient.
Case presentation: A 31-month-old male presented with a displaced odontoid fracture and ASIA C spinal cord injury. Given his age, closed reduction and halo application were completed under general anesthesia guided by neuromonitoring. A less-than-ideal reduction initially was accepted due to a decline in motor-evoked potentials. Subsequently, there was no change in neurological status. The reduction was repeated under anesthesia, with monitoring, a number of times until good correction was achieved. Ultimately, a surgical fusion was required due to ligamentous instability. The child achieved a very good neurological outcome and a stable spine.
Discussion: Neuromonitoring is an important adjunct to closed reductions when complete and reliable neurological assessment is not possible.

Objective: To describe the changes in the shape and topology of the somatosensory evoked potential (SSEP) during carotid endarterectomy, with particular reference to the time of clamping.
Methods: Routine intraoperative monitoring was performed on 30 patients undergoing carotid endarterectomy (15) or undergoing stenting (15) using median nerve SSEPs. Post-operatively the first and second derivatives of the potential were examined. Separate analysis of the SSEP using wavelets was also performed.
Results: In no instances did changes in the SSEP reach clinical significance. The first derivative showed significant changes that were temporally related to the clamp period. After clamping the 'velocity' was higher than baseline. There were changes in the wavelets related to the clamp period with more marked spectral edges at the conclusion of the procedure than baseline. In all instances the patient had a good clinical outcome.
Conclusions: Wavelet and derivative analysis of evoked potentials show changes that are not apparent with measures of amplitude and latency. The clinical relevance of these changes remains uncertain and await larger studies.
Significance: Increased velocity and spectral edges may be markers of increased cerebral blood flow, at least in the setting of pre-existing carotid stenosis.

Adult, Aged, Antibodies, Bispecific adverse effects, Antibodies, Bispecific pharmacokinetics, Antineoplastic Agents adverse effects, Antineoplastic Agents pharmacokinetics, CD3 Complex immunology, Carcinoembryonic Antigen immunology, Dose-Response Relationship, Drug, Female, Humans, Male, Maximum Tolerated Dose, Middle Aged, Single-Chain Antibodies administration dosage, Single-Chain Antibodies adverse effects, Single-Chain Antibodies pharmacokinetics, T-Lymphocytes drug effects, T-Lymphocytes immunology, Adenocarcinoma drug therapy, Antibodies, Bispecific administration dosage, Antineoplastic Agents administration dosage, Gastrointestinal Neoplasms drug therapy, and Immunotherapy methods

Introduction: MEDI-565, a bispecific, single-chain antibody targeting human carcinoembryonic antigen on tumor cells and the CD3 epsilon subunit of the human T-cell receptor complex, showed antitumor activity in carcinoembryonic antigen-expressing tumors in murine models.
Patients and Methods: This phase I, multicenter, open-label dose escalation study enrolled adults with gastrointestinal adenocarcinomas. MEDI-565 was given intravenously over 3 hours on days 1 through 5 in 28-day cycles, with 4 single-patient (0.75-20 μg) and 5 standard 3 + 3 escalation (60 μg-3 mg; 1.5-7.5 mg with dexamethasone) cohorts. Primary objective was determining maximum tolerated dose; secondary objectives were evaluating pharmacokinetics, antidrug antibodies, and antitumor activity.
Results: Thirty-nine patients were enrolled (mean age, 59 years; 56% male; 72% colorectal cancer). Four patients experienced dose-limiting toxicities (2 at 3 mg; 2 at 7.5 mg + dexamethasone): hypoxia (n = 2), diarrhea, and cytokine release syndrome (CRS). Five patients reported grade 3 treatment-related adverse events: diarrhea, CRS, increased alanine aminotransferase, hypertension (all, n = 1), and hypoxia (n = 2); 6 experienced treatment-related serious adverse events: diarrhea, vomiting, pyrexia, CRS (all, n = 1), and hypoxia (n = 2). MEDI-565 pharmacokinetics was linear and dose-proportional, with fast clearance and short half-life. Nineteen patients (48.7%) had antidrug antibodies; 5 (12.8%) had high titers, 2 with decreased MEDI-565 concentrations. No objective responses occurred; 11 (28%) had stable disease as best response.
Conclusions: The maximum tolerated dose of MEDI-565 in this patient population was 5 mg administered over 3 hours on days 1 through 5 every 28 days, with dexamethasone. Pharmacokinetics were linear. No objective responses were observed.
(Copyright © 2016 Elsevier Inc. All rights reserved.)

Functional Laterality, Humans, Cerebral Palsy, and Movement

Canada, Data Collection, Humans, Neurology, Neurophysiology, Practice Patterns, Physicians', Workforce, Attitude of Health Personnel, Diagnostic Techniques, Neurological, Monitoring, Intraoperative methods, and Surgeons

Intraoperative neuromonitoring is a specialized skill set performed in the operating room to reduce the risk of neurologic injury. There appears to be a shortage of qualified personnel and a lack of Canadian guidelines on the performance of the task. We distributed a web-based survey on the attitude of the surgeons to the interpretation of intraoperative neuromonitoring data among surgeons who use the technique. At present, most of the interpretation is performed by either technologists or by the surgeons themselves. Most surgeons would prefer professional oversight from a neurologist or neurophysiologist at the doctoral level. There is a lack of personnel in Canada with the appropriate training and expertise to interpret intraoperative neuromonitoring data.

Adolescent, Female, Humans, Male, Neural Tube Defects surgery, Neurosurgical Procedures methods, Predictive Value of Tests, Retrospective Studies, Scoliosis physiopathology, Scoliosis surgery, Spinal Cord physiopathology, Evoked Potentials, Motor, Evoked Potentials, Somatosensory, Monitoring, Intraoperative methods, Neural Tube Defects diagnosis, Neural Tube Defects physiopathology, Spinal Cord surgery, and Tibial Nerve physiopathology

Object: The diagnosis of tethered cord syndrome (TCS) remains difficult, and the decision to operate is even more complex. The objective of this study was to examine how detailed examination of neurophysiological test results can affect the diagnosis for patients undergoing a surgical cord release.
Methods: Patients undergoing tethered spinal cord releases were matched by age and sex with control patients undergoing scoliosis correction in the absence of spinal cord pathology. The latency and width of the P37 peak of the posterior tibial nerve somatosensory evoked potential (SSEP) and the motor evoked potential (MEP) latencies were examined. Immediate changes as a result of the surgical procedure were reported.
Results: The width of the P37 response differed significantly between TCS and control patients and changed significantly during the surgical procedure. Nonsignificant trends were seen in SSEP and MEP latencies.
Conclusions: The width of the P37 response may be a useful marker for TCS and may play a role in presurgical decision making.

Adult, Cerebral Palsy physiopathology, Child, Child, Preschool, Feasibility Studies, Female, Humans, Male, Phonation physiology, Vital Capacity physiology, Young Adult, Biomechanical Phenomena, Electromyography, Muscle Contraction physiology, Respiration, Speech physiology, and Thoracic Wall physiology

Objective: To develop a standardized paediatric protocol for acquiring simultaneous chest wall kinematics and surface electromyography (EMG) of chest wall muscles during maximum performance and speech tasks.
Patients and Methods: Eighteen healthy participants included: (a) a younger age group (n = 6; ages 4.0-6.5 years), (b) an older age group (n = 6; ages 7.0-10.5 years), and (c) an adult group (n = 8; ages 21-33 years). A child (age 10 years) with spastic-type cerebral palsy (CP) served as a 'proof of protocol feasibility'. Chest wall kinematics and surface EMGs (intercostals, rectus abdominus, external oblique, latissimus dorsi, and erector spinae) were acquired during maximum performance and speech tasks.
Results: Successful calibration of the EMG signal and reliable detection of muscle activation onset, offset, and amplitude relative to vital capacity and percent maximum voluntary contraction in children were demonstrated. Kinematic and surface EMG measurements were sensitive to non-speech and speech tasks, age, and neurological status (i.e. CP).
Conclusion: The simultaneous measurement of kinematics and EMG of the chest wall muscle groups provides a more comprehensive description of speech breathing in children. This protocol can be used for the observation and interpretation of clinical outcomes seen in children with motor speech disorders following treatments that focus on increasing overall respiratory and vocal effort.
(© 2016 S. Karger AG, Basel.)

Humans, Hydrocephalus surgery, Ventriculoperitoneal Shunt, Vibration, and Catheters

Biomedical catheters are commonly used to move fluids from one part of the body to another, or remove them from the body completely. In some instances, these catheters become occluded due to blood or other debris. Such occlusions may prove fatal or require re-operation with enormous costs and effects on the health-care system and the individual. We developed a model of occlusion in both a ventriculo-peritoneal shut system and en external ventricular drain. Having demonstrated that occlusions can be reliably generated in a manner that resembles the clinical situation we show that vibration can clear the blockages. Vibration in the 50-60 Hz range was able to maintain patency in the catheters or to clear the blockage when the catheter was completely occluded. In high concentrations of blood, 150 s of vibration applied every 30 min was able to maintain the patency of the catheter. Clinically, as the level of blood in the fluid decreases, the time intervals between vibration applications could be increased. We believe that vibration offers a safe, non-invasive method to maintain the patency of biomedical catheters.
(Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.)