1
|
Wilkinson MF, Galdino Chaves JP, Arroyo MV, Zarrabian M. Repeated L5 Nerve Root Compromise Detected with Motor Evoked Potentials (MEP), but Not Electromyography (EMG): A Case Report. Neurodiagn J 2024; 64:24-32. [PMID: 38437023 DOI: 10.1080/21646821.2024.2312098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2024] [Accepted: 01/24/2024] [Indexed: 03/06/2024]
Abstract
We report a case where neuromonitoring, using motor evoked potentials (MEP), detected an intraoperative L5 nerve root deficit during a lumbosacral decompression and instrumented fusion procedure. Critically, the MEP changes were not preceded nor accompanied by any significant spontaneous electromyography (sEMG) activity. Presumptive L5 innervated muscles, including tibialis anterior (TA), extensor hallucis longus (EHL) and gluteus maximus, were targets for nerve root surveillance using combined MEP and sEMG techniques. During a high-grade spondylolisthesis correction procedure, attempts to align a left-sided rod resulted in repeated loss and recovery cycles of MEP from the TA and EHL. No accompanying EMG alerts were associated with any of the MEP changes nor were MEP variations seen from muscles innervated above and below L5. After several attempts, the rod alignment was achieved, but significant MEP signal decrement (72% decrease) remained from the EHL. Postoperatively, the patient experienced significant foot drop on the left side that recovered over a period of 3 months. This case contributes to a growing body of evidence that exclusive reliance on sEMG for spinal nerve root scrutiny can be unreliable and MEP may provide more dependable data on nerve root patency.
Collapse
Affiliation(s)
- Marshall F Wilkinson
- Section of Neurosurgery, University of Manitoba and Health Sciences Centre, Winnipeg, Canada
| | - Jennyfer P Galdino Chaves
- Department of Orthopedic Surgery and Winnipeg Spine Program University of Manitoba and Health Sciences Centre, Winnipeg, Canada
| | - Miguel Vega Arroyo
- Department of Orthopedic Surgery and Winnipeg Spine Program University of Manitoba and Health Sciences Centre, Winnipeg, Canada
| | - Mohammed Zarrabian
- Department of Orthopedic Surgery and Winnipeg Spine Program University of Manitoba and Health Sciences Centre, Winnipeg, Canada
- Division of Orthopedic Surgery, McMaster University, Hamilton, Canada
| |
Collapse
|
2
|
Alvi MA, Kwon BK, Hejrati N, Tetreault LA, Evaniew N, Skelly AC, Fehlings MG. Accuracy of Intraoperative Neuromonitoring in the Diagnosis of Intraoperative Neurological Decline in the Setting of Spinal Surgery-A Systematic Review and Meta-Analysis. Global Spine J 2024; 14:105S-149S. [PMID: 38632716 PMCID: PMC10964897 DOI: 10.1177/21925682231196514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 04/19/2024] Open
Abstract
STUDY DESIGN Systematic review and meta-analysis. OBJECTIVES In an effort to prevent intraoperative neurological injury during spine surgery, the use of intraoperative neurophysiological monitoring (IONM) has increased significantly in recent years. Using IONM, spinal cord function can be evaluated intraoperatively by recording signals from specific nerve roots, motor tracts, and sensory tracts. We performed a systematic review and meta-analysis of diagnostic test accuracy (DTA) studies to evaluate the efficacy of IONM among patients undergoing spine surgery for any indication. METHODS The current systematic review and meta-analysis was performed using the Preferred Reporting Items for a Systematic Review and Meta-analysis statement for Diagnostic Test Accuracy Studies (PRISMA-DTA) and was registered on PROSPERO. A comprehensive search was performed using MEDLINE, EMBASE and SCOPUS for all studies assessing the diagnostic accuracy of neuromonitoring, including somatosensory evoked potential (SSEP), motor evoked potential (MEP) and electromyography (EMG), either on their own or in combination (multimodal). Studies were included if they reported raw numbers for True Positives (TP), False Negatives (FN), False Positives (FP) and True Negative (TN) either in a 2 × 2 contingency table or in text, and if they used postoperative neurologic exam as a reference standard. Pooled sensitivity and specificity were calculated to evaluate the overall efficacy of each modality type using a bivariate model adapted by Reitsma et al, for all spine surgeries and for individual disease groups and regions of spine. The risk of bias (ROB) of included studies was assessed using the quality assessment tool for diagnostic accuracy studies (QUADAS-2). RESULTS A total of 163 studies were included; 52 of these studies with 16,310 patients reported data for SSEP, 68 studies with 71,144 patients reported data for MEP, 16 studies with 7888 patients reported data for EMG and 69 studies with 17,968 patients reported data for multimodal monitoring. The overall sensitivity, specificity, DOR and AUC for SSEP were 71.4% (95% CI 54.8-83.7), 97.1% (95% CI 95.3-98.3), 41.9 (95% CI 24.1-73.1) and .899, respectively; for MEP, these were 90.2% (95% CI 86.2-93.1), 96% (95% CI 94.3-97.2), 103.25 (95% CI 69.98-152.34) and .927; for EMG, these were 48.3% (95% CI 31.4-65.6), 92.9% (95% CI 84.4-96.9), 11.2 (95% CI 4.84-25.97) and .773; for multimodal, these were found to be 83.5% (95% CI 81-85.7), 93.8% (95% CI 90.6-95.9), 60 (95% CI 35.6-101.3) and .895, respectively. Using the QUADAS-2 ROB analysis, of the 52 studies reporting on SSEP, 13 (25%) were high-risk, 10 (19.2%) had some concerns and 29 (55.8%) were low-risk; for MEP, 8 (11.7%) were high-risk, 21 had some concerns and 39 (57.3%) were low-risk; for EMG, 4 (25%) were high-risk, 3 (18.75%) had some concerns and 9 (56.25%) were low-risk; for multimodal, 14 (20.3%) were high-risk, 13 (18.8%) had some concerns and 42 (60.7%) were low-risk. CONCLUSIONS These results indicate that all neuromonitoring modalities have diagnostic utility in successfully detecting impending or incident intraoperative neurologic injuries among patients undergoing spine surgery for any condition, although it is clear that the accuracy of each modality differs.PROSPERO Registration Number: CRD42023384158.
Collapse
Affiliation(s)
- Mohammed Ali Alvi
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Brian K Kwon
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, BC, Canada
- Department of Orthopaedics, University of British Columbia, Vancouver, BC, Canada
| | - Nader Hejrati
- Division of Neurosurgery, Krembil Neuroscience Centre, Toronto Western Hospital, University Health Network, Toronto, ON, Canada
| | | | - Nathan Evaniew
- McCaig Institute for Bone and Joint Health, Department of Surgery, Orthopaedic Surgery, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | | | - Michael G Fehlings
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
- Division of Neurosurgery, Krembil Neuroscience Centre, Toronto Western Hospital, University Health Network, Toronto, ON, Canada
- Division of Neurosurgery and Spine Program, Department of Surgery, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
3
|
Michaeli A, Appel S, Danto J, Korn A, Schroeder JE. Intraoperative Deterioration of Neurophysiological Potentials of the Spinal Tracts in Cervical Spine Surgery: Correlation With Patient-Related and Procedure-Related Variables. J Clin Neurophysiol 2023; 40:325-330. [PMID: 35089908 DOI: 10.1097/wnp.0000000000000889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
PURPOSE To identify characteristics associated with higher incidence of intraoperative deterioration of neurophysiological potentials related to spinal tracts in cervical spine surgeries. METHODS Electrophysiological raw data and neurophysiological case reports of 1,611 patients from multiple medical centers, who underwent cervical spine surgery for decompression and/or fusion, were retrospectively reviewed. Patient-related and procedure-related variables were identified and analyzed for correlation with intraoperative neurophysiological event of the spinal tracts. The neurophysiological events were analyzed for identification of collective characteristics. RESULTS The study cohort presented consistent dominancy of male over female patients (67% vs. 33%). Intraoperative deterioration of spinal tract-derived potentials was noted in 10.5% of the total cases, which was not correlated with gender, age, or indication of the surgery. Higher incidence of neurophysiological events was noted in patients with impaired baseline of motor evoked potentials from the thenar muscle ( P = 0.01) or somatosensory evoked potentials of the posterior tibial nerve ( P = 0.0002). Procedures of circumferential approach or procedures that involved ≥3 spinal levels demonstrated higher incidence of neurophysiological events as well ( P = 0.0003 and 0.001, respectively). CONCLUSIONS Patients with deteriorated neurophysiological baseline and procedures of extensive intervention are at higher risk of intraoperative neurophysiological event in cervical spine surgery. Inclusion of intraoperative neurophysiological monitoring should be encouraged in complicated cases of cervical spine surgeries.
Collapse
Affiliation(s)
| | - Shmuel Appel
- Surgical Monitoring Services LTD, Beit Shemesh, Israel
- Department of Neurology, Barzilai Medical Center, Ashkelon, Israel, affiliated with the Joyce and Irving Goldman School of Medicine, Ben Gurion University of the Negev
| | - Joseph Danto
- Surgical Monitoring Services LTD, Beit Shemesh, Israel
| | - Akiva Korn
- Surgical Monitoring Services LTD, Beit Shemesh, Israel
- Departmet of Pediatric Neurosurgery, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel, affiliated with the Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel; and
| | - Josh E Schroeder
- Department of Orthopedics, Hadassah Medical Center and Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| |
Collapse
|
4
|
Yoshida G, Ushirozako H, Machino M, Shigematsu H, Kawabata S, Yamada K, Kanchiku T, Fujiwara Y, Iwasaki H, Ando M, Taniguchi S, Takatani T, Tadokoro N, Takahashi M, Wada K, Yamamoto N, Funaba M, Yasuda A, Hashimoto J, Morito S, Kurosu K, Kobayashi K, Ando K, Takeshita K, Matsuyama Y, Imagama S. Transcranial Motor-evoked Potentials for Intraoperative Nerve Root Monitoring During Adult Spinal Deformity Surgery: A Prospective Multicenter Study. Spine (Phila Pa 1976) 2022; 47:1590-1598. [PMID: 35905314 DOI: 10.1097/brs.0000000000004440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 07/06/2022] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN A prospective, multicenter study. OBJECTIVE This study clarified the uses and limitations of transcranial motor-evoked potentials (Tc-MEPs) for nerve root monitoring during adult spinal deformity (ASD) surgeries. SUMMARY OF BACKGROUND DATA Whether Tc-MEPs can detect nerve root injuries (NRIs) in ASD surgeries remains controversial. MATERIALS AND METHODS We prospectively analyzed neuromonitoring data from 14 institutions between 2017 and 2020. The subjects were ASD patients surgically treated with posterior corrective fusion using multichannel Tc-MEPs. An alert was defined as a decrease of ≥70% in the Tc-MEP's waveform amplitude from baseline, and NRI was considered as meeting the focal Tc-MEP alerts shortly following surgical procedures with postoperative nerve root symptoms in the selected muscles. RESULTS A total of 311 patients with ASD (262 women and 49 men) and a mean age of 65.5 years were analyzed. Tc-MEP results revealed 47 cases (15.1%) of alerts, including 25 alerts after 10 deformity corrections, six three-column osteotomies, four interbody fusions, three pedicle screw placements or two decompressions, and 22 alerts regardless of surgical maneuvers. Postoperatively, 14 patients (4.5%) had neurological deterioration considered to be all NRI, 11 true positives, and three false negatives (FN). Two FN did not reach a 70% loss of baseline (46% and 65% loss of baseline) and one was not monitored at target muscles. Multivariate logistic regression analysis revealed that risk factors of NRI were preexisting motor weakness ( P <0.001, odds ratio=10.41) and three-column osteotomies ( P =0.008, odds ratio=7.397). CONCLUSIONS Nerve root injuries in our ASD cohort were partially predictable using multichannel Tc-MEPs with a 70% decrease in amplitude as an alarm threshold. We propose that future research should evaluate the efficacy of an idealized warning threshold (e.g., 50%) and a more detailed evoked muscle selection, in reducing false negatives.
Collapse
Affiliation(s)
- Go Yoshida
- Department of Orthopedic Surgery, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Hiroki Ushirozako
- Department of Orthopedic Surgery, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Masaaki Machino
- Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Hideki Shigematsu
- Department of Orthopedic Surgery, Nara Medical University, Nara, Japan
| | - Shigenori Kawabata
- Department of Orthopedic Surgery, Tokyo Medical and Dental University, Tokyo, Japan
| | - Kei Yamada
- Department of Orthopedic Surgery, Kurume University School of Medicine, Kurume, Japan
| | - Tsukasa Kanchiku
- Department of Orthopedic Surgery, Yamaguchi Rosai Hospital, Yamaguchi, Japan
| | - Yasushi Fujiwara
- Department of Orthopedic Surgery, Hiroshima City Asa Citizens Hospital, Hiroshima, Japan
| | - Hiroshi Iwasaki
- Department of Orthopedic Surgery, Wakayama Medical University, Wakayama, Japan
| | - Muneharu Ando
- Department of Orthopedic Surgery, Kansai Medical University, Osaka, Japan
| | | | - Tsunenori Takatani
- Division of Central Clinical Laboratory, Nara Medical University, Nara, Japan
| | - Nobuaki Tadokoro
- Department of Orthopedic Surgery, Kochi University, Kochi, Japan
| | | | - Kanichiro Wada
- Department of Orthopedic Surgery, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Naoya Yamamoto
- Department of Orthopedic Surgery, Tokyo Women's Medical University Medical Center East, Tokyo, Japan
| | - Masahiro Funaba
- Department of Orthopedic Surgery, Yamaguchi University, Yamaguchi, Japan
| | - Akimasa Yasuda
- Department of Orthopedic Surgery, National Defense Medical College Hospital, Saitama, Japan
| | - Jun Hashimoto
- Department of Orthopedic Surgery, Tokyo Medical and Dental University, Tokyo, Japan
| | - Shinji Morito
- Department of Orthopedic Surgery, Kurume University School of Medicine, Kurume, Japan
| | - Kenta Kurosu
- Department of Orthopedic Surgery, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Kazuyoshi Kobayashi
- Department of Orthopedic Surgery, Nagoya Daini Red Cross Hospital, Nagoya, Japan
| | - Kei Ando
- Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Katsushi Takeshita
- Department of Orthopedic Surgery, Jichi Medical University, Tochigi, Japan
| | - Yukihiro Matsuyama
- Department of Orthopedic Surgery, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Shiro Imagama
- Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan
| |
Collapse
|
5
|
TAŞKIRAN E, KEMERDERE R, KÜÇÜKYÜRÜK B, TAHMAZOĞLU B, KAFADAR AM. Mapping and Monitoring During Surgery for Congenital Spinal Malformation. BEZMIALEM SCIENCE 2022. [DOI: 10.14235/bas.galenos.2020.4452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
|
6
|
Intraoperative neurophysiologic monitoring in thoracoabdominal aortic aneurysm surgery can provide real-time feedback for strategic decision making. Neurophysiol Clin 2022; 52:232-241. [PMID: 34998631 DOI: 10.1016/j.neucli.2021.12.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 12/19/2021] [Accepted: 12/20/2021] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVES Despite the introduction of several adjuncts to improve spinal perfusion, spinal cord ischemia (SCI) remains a devastating complication of thoracoabdominal aortic aneurysm (TAAA) repair. Our aim was to assess the effects on clinical outcome of interventions triggered by motor evoked potentials (MEP) alerts. Furthermore, we want to assess whether a multimodal intraoperative neurophysiologic monitoring (IONM) protocol is helpful for stratifying patients according to the risk of SCI at the end of the vascular phase of surgery. METHODS We prospectively studied one-hundred consecutive patients who underwent TAAA repair. We applied a multimodal IONM including MEP, somatosensory evoked potentials (SEP) and peripheral nerve monitoring techniques. Signal deteriorations were classified as reversible/irreversible according to whether they recovered or not at the end of monitoring (EOM), set at the end of the vascular phase of surgery. Significant MEP changes drove a series of corrective measures aimed to improve spinal perfusion. RESULTS The rate of immediate postoperative motor deficits consistent with SCI was significantly higher with irreversible MEP deteriorations compared to reversible ones. The interpretation of MEP findings at the EOM led to the development of risk categories for SCI, based on the association between MEP results and motor outcome. CONCLUSIONS Our data seem to justify interventions made to reverse MEP deterioration in order to improve the clinical outcome. A multimodal IONM protocol could improve MEP interpretation at the end of the vascular phase of surgery, supporting the surgeon in their decision-making, before concluding vascular maneuvers.
Collapse
|
7
|
Nuwer MR, MacDonald DB, Gertsch J. Monitoring scoliosis and other spinal deformity surgeries. HANDBOOK OF CLINICAL NEUROLOGY 2022; 186:179-204. [PMID: 35772886 DOI: 10.1016/b978-0-12-819826-1.00014-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Surgery to correct a spinal deformity incurs a risk of injury to the spinal cord and roots. Injuries include postoperative paraplegia. Surgery for cervical myelopathy also incurs risk for postoperative motor deficits, as well as nerve injury most commonly at the C5 root. Risks can be mitigated by monitoring the nervous system during surgery. Ideally, monitoring detects an impending injury in time to intervene and correct the impairment before it becomes permanent. Monitoring includes several modalities of testing. Somatosensory evoked potentials measure axonal conduction in the spinal cord posterior columns. This can be checked almost continuously during surgery. Motor evoked potentials measure conduction along the lateral corticospinal tracts. Because motor pathway stimulation often produces a patient movement on the table, these often are tested periodically rather than continuously. Electromyography observes for spontaneous discharges accompanying injuries, and is useful to assess misplacement of pedicle screws. Literature demonstrates the usefulness of these techniques, their association with reducing motor adverse outcomes, and the relative value of the techniques. Neurophysiologic monitoring for scoliosis, kyphosis, and cervical myelopathy surgery are addressed, along with background information about those conditions.
Collapse
Affiliation(s)
- Marc R Nuwer
- Departments of Neurology and Clinical Neurophysiology, David Geffen School of Medicine, University of California Los Angeles, and Ronald Reagan UCLA Medical Center, Los Angeles, CA, United States.
| | | | - Jeffrey Gertsch
- Department of Neurology, UC San Diego Health, San Diego, CA, United States
| |
Collapse
|
8
|
Intraoperative neuromonitoring practice patterns in spinal deformity surgery: a global survey of the Scoliosis Research Society. Spine Deform 2021; 9:315-325. [PMID: 33230669 DOI: 10.1007/s43390-020-00246-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 10/30/2020] [Indexed: 10/22/2022]
Abstract
PURPOSE Although multimodal IONM has reached a widespread use, several unresolved issues have remained in clinical practice. The aim was to determine differences in approaches to form a basis for taking actions to improve patient safety globally. METHODS A survey comprising 19 questions in four sections (demographics, setup, routine practices and reaction to alerts) was distributed to the membership of the SRS. RESULTS Of the estimated 1300 members, 205 (~ 15%) completed the survey. Respondent demographics reflected SRS member distribution. Most of the respondents had > 10 years of experience. TcMEP and SSEP were available to > 95%. Less than 5% reported that a MD/PhD with neurophysiology background routinely examines patients preoperatively, while 19% would consult if requested. After an uneventful case, 36% reported that they would decrease sedation and check motor function if the patient was to be transferred to ICU intubated. Reactions to dropped signals that recovered or did not fully recover varied between attempting the same correction to aborting the surgery with no rods and returning another day, with or without implant removal. After a decrease of signals, 85.7% use steroids of varied doses. Of the respondents, 53.7% reported using the consensus-created checklist by Vitale et al. Approximately, 14% reported never using the wake-up test while others use it for various conditions. CONCLUSION The responses of 205 experienced SRS members from different regions of the world showed that surgeons had different approaches in their routine IONM practices and in the handling of alerts. This survey indicates the need for additional studies to identify best practices.
Collapse
|
9
|
Charalampidis A, Jiang F, Wilson JRF, Badhiwala JH, Brodke DS, Fehlings MG. The Use of Intraoperative Neurophysiological Monitoring in Spine Surgery. Global Spine J 2020; 10:104S-114S. [PMID: 31934514 PMCID: PMC6947672 DOI: 10.1177/2192568219859314] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
STUDY DESIGN Narrative review. OBJECTIVE To summarize relevant studies regarding the utilization of intraoperative neurophysiological monitoring (IONM) techniques in spine surgery implemented in recent years. METHODS A literature search of the Medline database was performed. Relevant studies from all evidence levels have been included. Titles, abstracts, and reference lists of key articles were included. RESULTS Multimodal intraoperative neurophysiological monitoring (MIONM) has the advantage of compensating for the limitations of each individual technique and seems to be effective and accurate for detecting perioperative neurological injury during spine surgery. CONCLUSION Although there are no prospective studies validating the efficacy of IONM, there is a growing body of evidence supporting its use during spinal surgery. However, the lack of validated protocols to manage intraoperative alerts highlights a critical knowledge gap. Future investigation should focus on developing treatment methodology, validating practice protocols, and synthesizing clinical guidelines.
Collapse
Affiliation(s)
- Anastasios Charalampidis
- Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada,Department of Clinical Sciences, Intervention and Technology (CLINTEC), Karolinska Institutet, Stockholm, Sweden,Department of Reconstructive Orthopaedics, Karolinska University Hospital, Stockholm, Sweden
| | - Fan Jiang
- Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada,University of Toronto, Toronto, Ontario, Canada
| | - Jamie R. F. Wilson
- Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada,University of Toronto, Toronto, Ontario, Canada
| | - Jetan H. Badhiwala
- Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada,University of Toronto, Toronto, Ontario, Canada
| | | | - Michael G. Fehlings
- Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada,University of Toronto, Toronto, Ontario, Canada,Michael G. Fehlings, Division of Neurosurgery, Toronto Western Hospital, University of Toronto, 399 Bathurst St, Toronto, Ontario M5T2S8, Canada.
| |
Collapse
|
10
|
Yi YG, Kim K, Shin HI, Bang MS, Kim HS, Choi J, Wang KC, Kim SK, Lee JY, Phi JH, Seo HG. Feasibility of intraoperative monitoring of motor evoked potentials obtained through transcranial electrical stimulation in infants younger than 3 months. J Neurosurg Pediatr 2019; 23:758-766. [PMID: 30875681 DOI: 10.3171/2019.1.peds18674] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 01/21/2019] [Indexed: 11/06/2022]
Abstract
OBJECTIVE This study aimed to investigate the feasibility and safety of intraoperative motor evoked potential (MEP) monitoring in infants less than 3 months of age. METHODS The authors investigated 25 cases in which infants younger than 3 months (mean age 72.8 days, range 39-87) underwent neurosurgery between 2014 and 2017. Myogenic MEPs were obtained through transcranial electrical stimulation. In all cases, surgery was performed under total intravenous anesthesia, maintained with remifentanil and propofol. RESULTS MEPs were documented in 24 infants, the sole exception being 1 infant who was lethargic and had 4-limb weakness before surgery. The mean stimulation intensity maintained during monitoring was 596 ± 154 V (range 290-900 V). In 19 of 24 infants MEP signals remained at ≥ 50% of the baseline amplitude throughout the operation. Among 5 cases with a decrease in intraoperative MEP amplitude, the MEP signal was recovered in one during surgery, and in the other case a neurological examination could not be performed after surgery. In the other 3 cases, 2 infants had relevant postoperative weakness and the other did not show postoperative neurological deficits. Postoperative weakness was not observed in any of the 20 infants who had no deterioration (n = 19) or only temporary deterioration (n = 1) in MEP signal during surgery. CONCLUSIONS Transcranial electrical MEPs could be implemented during neurosurgery in infants between 1 and 3 months of age. Intraoperative MEP monitoring may be a safe adjunct for neurosurgical procedures in these very young patients.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Kyu-Chang Wang
- 3Neurosurgery, Seoul National University College of Medicine and Seoul National University Hospital; and
- 4Division of Pediatric Neurosurgery, Seoul National University Children's Hospital, Seoul, Republic of Korea
| | - Seung-Ki Kim
- 3Neurosurgery, Seoul National University College of Medicine and Seoul National University Hospital; and
- 4Division of Pediatric Neurosurgery, Seoul National University Children's Hospital, Seoul, Republic of Korea
| | - Ji Yeoun Lee
- 3Neurosurgery, Seoul National University College of Medicine and Seoul National University Hospital; and
- 4Division of Pediatric Neurosurgery, Seoul National University Children's Hospital, Seoul, Republic of Korea
| | - Ji Hoon Phi
- 3Neurosurgery, Seoul National University College of Medicine and Seoul National University Hospital; and
- 4Division of Pediatric Neurosurgery, Seoul National University Children's Hospital, Seoul, Republic of Korea
| | | |
Collapse
|
11
|
Kozaki T, Tsutsui S, Yamada H. Transcranial motor evoked potentials electrically elicited by multi-train stimulation can reflect isolated nerve root injury more precisely than those by conventional multi-pulse stimulation: an experimental study in rats. J Clin Monit Comput 2019; 34:125-129. [PMID: 30835023 DOI: 10.1007/s10877-019-00296-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Accepted: 03/01/2019] [Indexed: 11/29/2022]
Abstract
Nerve root injury can occur in complex spine surgeries. Recording transcranial motor-evoked potentials (TcMEPs) has been the most popular method to monitor motor function during surgery. However, TcMEPs cannot detect single nerve root injury satisfactorily. Recently, multi-train stimulation (MTS) was demonstrated to effectively enhance TcMEPs. The aim of this study was to investigate the utility of TcMEPs elicited by MTS for intraoperative nerve root monitoring. TcMEPs were recorded from the quadriceps femoris (QF) and gastrocnemius (GC) muscles in the hindlimbs of 20 rats before and after transection of the nerve root at L6 (dominant root innervating the GC). For MTS, a multipulse (train) stimulus was delivered repeatedly at 5 Hz. The change ratio of the amplitude after transection of the nerve root was compared between MTS and conventional single-train stimulation (STS). The change in TcMEP amplitudes for QF after transection of the nerve root at L6 was 97.8 ± 12.2% with MTS and 100.1 ± 7.2% with STS (p = 0.496), whereas that for GC was 40.6 ± 11.5% with MTS and 64.8 ± 8.8% with STS (p < 0.001). MTS could improve the ability to detect isolated nerve root injury in intraoperative TcMEP monitoring.
Collapse
Affiliation(s)
- Takuhei Kozaki
- Department of Orthopedic Surgery, Wakayama Medical University, 811-1 Kimiidera, Wakayama, 641-8510, Japan
| | - Shunji Tsutsui
- Department of Orthopedic Surgery, Wakayama Medical University, 811-1 Kimiidera, Wakayama, 641-8510, Japan.
| | - Hiroshi Yamada
- Department of Orthopedic Surgery, Wakayama Medical University, 811-1 Kimiidera, Wakayama, 641-8510, Japan
| |
Collapse
|
12
|
Lieberman JA, Lyon R, Jasiukaitis P, Berven SH, Burch S, Feiner J. The reliability of motor evoked potentials to predict dorsiflexion injuries during lumbosacral deformity surgery: importance of multiple myotomal monitoring. Spine J 2019; 19:377-385. [PMID: 30025994 DOI: 10.1016/j.spinee.2018.07.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 07/08/2018] [Accepted: 07/09/2018] [Indexed: 02/03/2023]
Abstract
STUDY DESIGN Case-control analysis of transcranial motor evoked potential (MEP) responses and clinical outcome. OBJECTIVE To determine the sensitivity and specificity of MEPs to predict isolated nerve root injury causing dorsiflexion weakness in selected patients having complex lumbar spine surgery. SUMMARY OF BACKGROUND DATA The surgical correction of distal lumbar spine deformity involves significant risk for damage to neural structures that control muscles of ankle and toe dorsiflexion. Procedures often include vertebral translation, interbody fusion, and posterior-based osteotomies. The benefit of using MEP monitoring to predict dorsiflexion weakness has not been well-established. The purpose of this paper is to describe the relationship between neural complications from lumbar surgery and intraoperative MEP changes. METHODS Included were 542 neurologically intact patients who underwent posterior spinal fusion for the correction of distal lumbar deformity. Two myotomes, including tibialis anterior (TA) and extensor hallucis longus (EHL), were monitored. MEP and free-running electromyography data were assessed in each patient. Cases of new dorsiflexion weakness noted postoperatively were identified. Data in case and control patients were compared. There was no direct funding for this work. The Department of Anesthesiology and Perioperative Care provides salary support for authors one and six. Authors two and three report employment in the field of intraoperative neurophysiological monitoring as a study-specific conflict of interest. RESULTS Twenty-five patients (cases) developed dorsiflexion weakness. MEP amplitude decreased in the injured myotomes by an average of 65 ± 21% (TA) and 60±26% (EHL), which was significantly greater than the contralateral uninjured side or for control subjects. (p < .01) Receiver operator characteristic (ROC) curves showed high sensitivity, specificity, and predictive value for changes in MEP amplitude using either the TA or EHL. Analysis of MEP changes to either TA or EHL yielded a superior ROC curve. Net reclassification improvement analysis showed assessing MEP changes to both TA and EHL improved the predictability of injury. CONCLUSIONS The use of MEP amplitude change is highly sensitive and specific to predict a new postoperative dorsiflexion injury. Monitoring two myotomes (both TA and EHL) is superior to relying on MEP changes from a single myotome. Electromyography activity was less accurate but compliments MEP use. Additional studies are needed to define optimal intraoperative MEP warning thresholds.
Collapse
Affiliation(s)
- Jeremy A Lieberman
- Department of Anesthesia & Perioperative Care, University of California, San Francisco, San Francisco, CA 94143, USA.
| | - Russ Lyon
- Division of Operating Room Services, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Paul Jasiukaitis
- Division of Operating Room Services, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Sigurd H Berven
- Department of Orthopedic Surgery, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Shane Burch
- Department of Orthopedic Surgery, University of California, San Francisco, San Francisco, CA 94143, USA
| | - John Feiner
- Department of Anesthesia & Perioperative Care, University of California, San Francisco, San Francisco, CA 94143, USA
| |
Collapse
|
13
|
Jasiukaitis P, Lyon R. Trending algorithm discriminates hemodynamic from injury related TcMEP amplitude loss. J Clin Monit Comput 2019; 34:131-137. [PMID: 30726520 DOI: 10.1007/s10877-019-00272-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 01/30/2019] [Indexed: 10/27/2022]
Abstract
Jasiukaitis and Lyon (J Clin Monit Comput, https://doi.org/10.1007/s10877-018-0181-9, 2018) described an motor evoked potential (MEP)amplitude trending system to detect MEP amplitude loss against a background of MEP variability. They found that the end of case value of a running R2 triggered by a set MEP amplitude loss criterion appeared to discriminate new injury from non-injury in a small sample of three patients. The present study examines the predictive capability of the running R2 in a larger sample of patients (21 injured and 19 non-injured). It also varies the amplitude loss criterion (50%, 65% and 80%) for triggering the running R2 and the numbers of points used in the moving linear regression (8, 12 and 16). 40 patients who had undergone correction for lumbar deformity were retrospectively examined. 21 of these woke up with a newly acquired radicular injury, 19 did not but were characterized by hypovolemic hemorrhage. All 40 patients had sufficient MEP amplitude loss sometime during their procedure to cause the monitoring specialist to report this to the surgeon and anesthesia. End-of-case running R2s were significantly larger in the injury group. Using an 80% amplitude loss criterion to trigger the running R2 proved to be too stringent, causing reduced sensitivity. The running R2 appeared to have equivalent sensitivity to that of conventional MEP amplitude loss ratios, but superior specificity within this monitoring challenged sample. The different number of points for the moving regressions did not have any significant effect. End-of-case R2 values greater than 60% appeared to be highly predictive of new post-operative deficit, while values less than 40% appeared to insure no new deficit. The proposed trending system can discriminate injury from non-injury outcomes when compressive radicular injury during correction for lumbar deformity is involved. This discrimination appears to be successful even when MEP amplitude loss for non-iatrogenic reasons (i.e., hemorrhage) is also occurring.
Collapse
Affiliation(s)
| | - Russ Lyon
- DABNM, Division of Operating Rooms, University of California San Francisco, San Francisco, CA, USA
| |
Collapse
|
14
|
Yalınay Dikmen P, Ozden VE, Dikmen G, Aydınlar EI, Tozun IR. Intraoperative neuromonitoring of anterior root muscle response during hip surgery under spinal anesthesia. J Clin Monit Comput 2018; 33:695-702. [PMID: 30415323 DOI: 10.1007/s10877-018-0212-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 10/10/2018] [Indexed: 11/25/2022]
Abstract
The aim of this study was to evaluate the anterior root muscle (ARM) response monitorability during total hip arthroplasty (THA) under spinal anesthesia. A total of 20 adults (64.6 ± 13.87 years old) were monitored using ARM response and free-run electromyography during THA. To elicit the ARM response from muscles, percutaneous stimulation of the lumbosacral roots was performed by self-adhesive electrodes placed over the skin of the projection of the first and third lumbar interspinous space (anode) and over the abdominal skin of the umbilicus (cathode). Latency and amplitude values of the ARM response were recorded from both sides (non-operated and operated) and from five muscles as follows: rectus femoris (RF), vastus lateralis (VL), biceps femoris long-head (BF), Tibialis Anterior (TA) and gastrocnemius. The most recorded ARM response in a muscle was the TA (n = 38); the least recorded AMR response in a muscle was the BF (n = 33). The mean stimulus intensities for the non-operated and the operated sides were 462.5 ± 112.8 V and 520.0 ± 172.3 V (p = 0.834), respectively. The mean latencies and amplitude values of the ARM response from muscles were as follows: 8.8 ± 1.4 ms; 98.8 ± 114.5 µV for RF; 9.8 ± 2.1 ms; 119.1 ± 122.23 µV for VL; 9.5 ± 1.6 ms; 39.6 ± 30.3 µV for BF; 15.1 ± 1.9 ms; 146.6 ± 150.9 µV for TA; 15.6 ± 2.4 ms; 81.0 ± 99.9 µV for Gastrocnemius. The present study demonstrates that the ARM response could easily and safely be obtained during THA under spinal anesthesia. This non-invasive technique may have a potential to detect early neurological deficit in patients who need complex hip surgery under spinal anesthesia.
Collapse
Affiliation(s)
- Pınar Yalınay Dikmen
- Neurology Department, School of Medicine, Acıbadem Mehmet Ali Aydınlar University, Ic Erenkoy Mah. Kerem Aydınlar Kampusu, Kayısdag Cad., Atasehir, 34752, Istanbul, Turkey.
- Department of Neurology, Maslak Acıbadem Hospital, Büyükdere Caddesi. No: 40, 34390, Istanbul, Turkey.
| | - V Emre Ozden
- Orthopedic and Traumatology Department, School of Medicine, Acıbadem Mehmet Ali Aydınlar University, Ic Erenkoy Mah. Kerem Aydınlar Kampusu. Kayısdag Cad. Atasehir, 34752, Istanbul, Turkey
| | - Goksel Dikmen
- Orthopedic and Traumatology Department, School of Medicine, Acıbadem Mehmet Ali Aydınlar University, Ic Erenkoy Mah. Kerem Aydınlar Kampusu. Kayısdag Cad. Atasehir, 34752, Istanbul, Turkey
| | - Elif Ilgaz Aydınlar
- Neurology Department, School of Medicine, Acıbadem Mehmet Ali Aydınlar University, Ic Erenkoy Mah. Kerem Aydınlar Kampusu, Kayısdag Cad., Atasehir, 34752, Istanbul, Turkey
| | - I Remzi Tozun
- Orthopedic and Traumatology Department, School of Medicine, Acıbadem Mehmet Ali Aydınlar University, Ic Erenkoy Mah. Kerem Aydınlar Kampusu. Kayısdag Cad. Atasehir, 34752, Istanbul, Turkey
| |
Collapse
|
15
|
Riley MR, Doan AT, Vogel RW, Aguirre AO, Pieri KS, Scheid EH. Use of motor evoked potentials during lateral lumbar interbody fusion reduces postoperative deficits. Spine J 2018; 18:1763-1778. [PMID: 29505853 DOI: 10.1016/j.spinee.2018.02.024] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 01/16/2018] [Accepted: 02/23/2018] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT Intraoperative neurophysiological monitoring (IONM) has gained rather widespread acceptance as a method to mitigate risk to the lumbar plexus during lateral lumbar interbody fusion (LLIF) surgery. The most common approach to IONM involves using only electromyography (EMG) monitoring, and the rate of postoperative deficit remains unacceptably high. Other test modalities, such as transcranial electric motor-evoked potentials (tcMEPs) and somatosensory-evoked potentials, may be more suitable for monitoring neural integrity, but they have not been widely adopted during LLIF. Recent studies have begun to examine their utility in monitoring LLIF surgery with favorable results. PURPOSE This study aimed to evaluate the efficacy of different IONM paradigms in the prevention of iatrogenic neurologic sequelae during LLIF and to specifically evaluate the utility of including tcMEPs in an IONM strategy for LLIF surgery. STUDY DESIGN/SETTING A non-randomized, retrospective analysis of 479 LLIF procedures at a single institution over a 4-year period was conducted. During the study epoch, three different IONM strategies were used for LLIF procedures: (1) surgeon-directed T-EMG monitoring ("SD-EMG"), (2) neurophysiologist-controlled T-EMG monitoring ("NC-EMG"), and (3) neurophysiologist-controlled T-EMG monitoring supplemented with MEP monitoring ("NC-MEP"). PATIENT SAMPLE The patient population comprised 254 men (53.5%) and 221 women (46.5%). Patient age ranged from a minimum of 21 years to a maximum of 89 years, with a mean of 56.6 years. OUTCOME MEASURES Physician-documented physiological measures included manual muscle test grading of hip-flexion, hip-adduction, or knee-extension, as well as hypo- or hyperesthesia of the groin or anterolateral thigh on the surgical side. Self-reported measures included numbness or tingling in the groin or anterolateral thigh on the surgical side. METHODS Patient progress notes were reviewed from the postoperative period up to 12 months after surgery. The rates of postoperative sensory-motor deficit consistent with lumbar plexopathy or peripheral nerve palsy on the surgical side were compared between the three cohorts. RESULTS Using the dependent measure of neurologic deficit, whether motor or sensory, patients with NC-MEP monitoring had the lowest rate of immediate postoperative deficit (22.3%) compared with NC-EMG monitoring (37.1%) and SD-EMG monitoring (40.4%). This result extended to sensory deficits consistent with lumbar plexopathy (pure motor deficits being excluded); patients with NC-MEP monitoring had the lowest rate (20.5%) compared with NC-EMG monitoring (34.3%) and SD-EMG monitoring (36.9%). Additionally, evaluation of postoperative motor deficits consistent with peripheral nerve palsy (pure sensory deficits being excluded) revealed that the NC-MEP group had the lowest rate (5.7%) of motor deficit compared with the SD-EMG (17.0%) and NC-EMG (17.1%) cohorts. Finally, when assessing only those patients whose last follow-up was greater than or equal to 12 months (n=251), the rate of unresolved motor deficits was significantly lower in the NC-MEP group (0.9%) compared with NC-EMG (6.9%) and SD-EMG (11.0%). A comparison of the NC-MEP versus NC-EMG and SD-EMG groups, both independently and combined, was statistically significant (>95% confidence level) for all analyses. CONCLUSIONS The results of the present study indicate that preservation of tcMEPs from the adductor longus, quadriceps, and tibialis anterior muscles are of paramount importance for limiting iatrogenic sensory and motor injuries during LLIF surgery. In this regard, the inclusion of tcMEPs serves to compliment EMG and allows for the periodic, functional assessment of at-risk nerves during these procedures. Thus, tcMEPs appear to be the most effective modality for the prevention of both transient and permanent neurologic injury during LLIF surgery. We propose that the standard paradigm for protecting the nervous system during LLIF be adapted to include tcMEPs.
Collapse
Affiliation(s)
- Michael R Riley
- SafePassage Patient Monitoring Services LLC, 915 Broadway Suite 1200, New York, NY 10010, USA.
| | - Adam T Doan
- SafePassage Patient Monitoring Services LLC, 915 Broadway Suite 1200, New York, NY 10010, USA
| | - Richard W Vogel
- SafePassage Patient Monitoring Services LLC, 915 Broadway Suite 1200, New York, NY 10010, USA
| | - Alexander O Aguirre
- Department of Neuroscience, Syracuse University, 362 Life Sciences Complex, Syracuse, NY, USA
| | - Kayla S Pieri
- Department of Biochemistry, Elon University, 2625 Campus Box, Elon, NC 27244, USA
| | - Edward H Scheid
- Capital Region Special Surgery PLLC, 1220 New Scotland Rd, Slingerlands, NY 12159, USA
| |
Collapse
|
16
|
A new criterion for detection of radiculopathy based on motor evoked potentials and intraoperative nerve root monitoring. Clin Neurophysiol 2018; 129:2075-2082. [PMID: 30077868 DOI: 10.1016/j.clinph.2018.07.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Revised: 07/08/2018] [Accepted: 07/09/2018] [Indexed: 11/21/2022]
Abstract
OBJECTIVE Our objective is to use the area of the motor evoked potential (MEP) as a diagnostic tool for intraoperative radicular injury. METHODS We analyzed the intraoperative neurophysiological monitoring data and clinical outcomes of 203 patients treated for dorsolumbar spine deformity. The decrease in amplitude was compared with the reduction in the MEP area. RESULTS In 11 cases, new intraoperative injuries occurred, nine of them were lumbar radiculopathies. Our new criteria, a decrease MEP area of 70%, yielded a sensitivity and specificity of 1, since it detected all the radicular injuries, with no false positive cases. Using a 70% amplitude decrease criteria, we obtained a sensitivity of 0,89 and a specificity of 0,99. A lower threshold (65% amplitude reduction) yielded a higher number of false positives, whereas a higher threshold (75 and 80%) gave rise to a higher number of false negatives. CONCLUSIONS The measurement of the MEP area gave evidence to be more reliable and accurate than the measurement of the amplitude reduction in order to assess and detect intraoperative radicular injuries. SIGNIFICANCE The criterion of decrease of the MEP area has a higher reliability and accuracy in the detection of intraoperative radicular lesions than the amplitude reduction.
Collapse
|
17
|
Differences in the Transcranial Motor Evoked Potentials Between Proximal and Distal Lower Extremity Muscles. J Clin Neurophysiol 2018; 35:155-158. [DOI: 10.1097/wnp.0000000000000454] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|
18
|
Zyss J, Bernat I, Wolff S, Riouallon G, Pascal-Moussellard H. Limitations and pitfalls of the pedicle screw testing monitoring technique: An in vivo and in vitro study. Neurophysiol Clin 2017; 47:393-403. [PMID: 29111396 DOI: 10.1016/j.neucli.2017.09.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 09/15/2017] [Accepted: 09/26/2017] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVES Pedicle screw testing is a widely used technique in the field of neuromonitoring for spinal surgery. It was designed by Calancie et al. (1992) in order to detect pedicle breach, one of the major complications of pedicle screw fixation, which can lead to neurological impairment. However, numerous false negative and equivocal results led to its clinical relevance being questioned. We aimed to clarify these discrepancies and characterize electrical parameters underlying this technique. METHODS In this setting, our study is divided into two parts: (1) a clinical part assessing the difference between direct pedicle hole via the pedicle perforator stimulation and indirect stimulation via the implanted screw; (2) an in vitro study testing the electrical properties (resistivity and conductivity) on a sample of different commonly used pedicle screws. RESULTS We showed that there were discrepancies between direct perforator stimulation and pedicle screws, especially at high threshold values. These might be attributed to electrical contact discontinuity. In vitro testing revealed that the previously described resistivity variability and the instability of measures are due to the result of slight changes of position of the recording contacts. CONCLUSION Electrical continuity is crucial in the pedicle screw test technique. This parameter cannot actually be fully ensured and can lead to discrepancies and potentially false negative results. Therefore, we recommend the use of both direct stimulation of the pedicle hole and control testing of the screw. Further studies and improvement of the technique are required to ensure its reliability.
Collapse
Affiliation(s)
- Julie Zyss
- Clinical Neurophysiology Department, groupe hospitalier Pitié-Salpêtrière, 47-83, boulevard de l'Hôpital, 75013 Paris, France.
| | - Isabelle Bernat
- Clinical Neurophysiology Department, groupe hospitalier Pitié-Salpêtrière, 47-83, boulevard de l'Hôpital, 75013 Paris, France
| | - Stéphane Wolff
- Department of Orthopaedic Surgery, groupe hospitalier Paris-Saint-Joseph, 185, rue Raymond-Losserand, 75014 Paris, France
| | - Guillaume Riouallon
- Department of Orthopaedic Surgery, groupe hospitalier Paris-Saint-Joseph, 185, rue Raymond-Losserand, 75014 Paris, France
| | - Hugues Pascal-Moussellard
- Department of orthopaedic Surgery, groupe hospitalier Pitié-Salpêtrière, 47-83, boulevard de l'Hôpital, 75013 Paris, France
| |
Collapse
|
19
|
Higher success rate with transcranial electrical stimulation of motor-evoked potentials using constant-voltage stimulation compared with constant-current stimulation in patients undergoing spinal surgery. Spine J 2017; 17:1472-1479. [PMID: 28483707 DOI: 10.1016/j.spinee.2017.05.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 03/11/2017] [Accepted: 05/02/2017] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT During spine surgery, the spinal cord is electrophysiologically monitored via transcranial electrical stimulation of motor-evoked potentials (TES-MEPs) to prevent injury. Transcranial electrical stimulation of motor-evoked potential involves the use of either constant-current or constant-voltage stimulation; however, there are few comparative data available regarding their ability to adequately elicit compound motor action potentials. We hypothesized that the success rates of TES-MEP recordings would be similar between constant-current and constant-voltage stimulations in patients undergoing spine surgery. PURPOSE The objective of this study was to compare the success rates of TES-MEP recordings between constant-current and constant-voltage stimulation. STUDY DESIGN This is a prospective, within-subject study. PATIENT SAMPLE Data from 100 patients undergoing spinal surgery at the cervical, thoracic, or lumbar level were analyzed. OUTCOME MEASURES The success rates of the TES-MEP recordings from each muscle were examined. MATERIALS AND METHODS Transcranial electrical stimulation with constant-current and constant-voltage stimulations at the C3 and C4 electrode positions (international "10-20" system) was applied to each patient. Compound muscle action potentials were bilaterally recorded from the abductor pollicis brevis (APB), deltoid (Del), abductor hallucis (AH), tibialis anterior (TA), gastrocnemius (GC), and quadriceps (Quad) muscles. RESULTS The success rates of the TES-MEP recordings from the right Del, right APB, bilateral Quad, right TA, right GC, and bilateral AH muscles were significantly higher using constant-voltage stimulation than those using constant-current stimulation. The overall success rates with constant-voltage and constant-current stimulations were 86.3% and 68.8%, respectively (risk ratio 1.25 [95% confidence interval: 1.20-1.31]). CONCLUSIONS The success rates of TES-MEP recordings were higher using constant-voltage stimulation compared with constant-current stimulation in patients undergoing spinal surgery.
Collapse
|
20
|
Ohashi M, Watanabe K, Furutani K, Hirano T, Katsumi K, Shoji H, Mizouchi T, Endo N. False-negative transcranial motor evoked potentials (TcMEPs) during surgery for congenital lumbar kyphoscoliosis: a case report. Spinal Cord Ser Cases 2017; 3:17053. [PMID: 28944085 DOI: 10.1038/scsandc.2017.53] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 06/24/2017] [Accepted: 07/10/2017] [Indexed: 11/09/2022] Open
Abstract
INTRODUCTION Transcranial motor evoked potential (TcMEP) monitoring is the gold standard for intra-operative neurological monitoring (IOM) of motor pathways during complex spine surgery because of its high sensitivity and specificity. However, although it is very low, the rate of false-negatives in TcMEP monitoring is not zero. Therefore, over-reliance on TcMEP monitoring can cause potentially preventable motor deficits. CASE PRESENTATION We report a case of motor deficits due to nerve root stretch after surgical correction of a congenital lumbar kyphoscoliosis in a 56-year-old woman. TcMEPs did not show any significant changes during surgery, whereas free-run electromyography (EMG) demonstrated a long-lasting train activity in the left quadriceps femoris muscle (QF) after correction at the osteotomy area. According to the normal findings on TcMEP monitoring, we did not release the correction. Postoperatively, a significant decrease (grade 2-) in the manual muscle test for the left QF and iliopsoas muscle and hypesthesia of the left anterior thigh was revealed. Fortunately, muscle strength was fully recovered without revision surgery at 6 months postoperatively; however, numbness in the left anterior thigh persisted at 2 years after surgery. DISCUSSION Our report suggests that the possibility of false-negative TcMEPs should be kept in mind, especially during surgery with a risk of nerve root injury. When abnormal findings in the free-run EMG, including long-lasting train activity, are observed, surgeons should consider performing appropriate responses, such as the release of the correction, even when no substantial changes are seen in the TcMEPs.
Collapse
Affiliation(s)
- Masayuki Ohashi
- Division of Orthopaedic Surgery, Department of Regenerative and Transplant Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata City, Niigata, Japan
| | - Kei Watanabe
- Division of Orthopaedic Surgery, Department of Regenerative and Transplant Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata City, Niigata, Japan
| | - Kenta Furutani
- Division of Anesthesiology, Niigata University Graduate School of Medical and Dental Sciences, Niigata City, Niigata, Japan
| | - Toru Hirano
- Division of Orthopaedic Surgery, Department of Regenerative and Transplant Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata City, Niigata, Japan
| | - Keiichi Katsumi
- Department of Orthopedic Surgery, Uonuma Kikan Hospital, Minami-Uonuma City, Niigata, Japan
| | - Hirokazu Shoji
- Division of Orthopaedic Surgery, Department of Regenerative and Transplant Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata City, Niigata, Japan
| | - Tatsuki Mizouchi
- Division of Orthopaedic Surgery, Department of Regenerative and Transplant Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata City, Niigata, Japan
| | - Naoto Endo
- Division of Orthopaedic Surgery, Department of Regenerative and Transplant Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata City, Niigata, Japan
| |
Collapse
|
21
|
Choi YD, Jin SH, Kim CH, Kwak GH, Kim BE, Chung CK. An Electrode Configuration for Recording Muscle Motor Evoked Potentials in the Upper Extremities during Intraoperative Neurophysiological Monitoring. J Korean Neurosurg Soc 2017; 60:475-480. [PMID: 28689398 PMCID: PMC5544366 DOI: 10.3340/jkns.2016.0506.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 12/31/2016] [Accepted: 01/05/2017] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE The main aim of the present study is to examine the electrode configurations used to record the muscle motor evoked potential (mMEP) in the upper extremities during surgery with the goal of producing a high and stable mMEP signal, in particular among the abductor pollicis brevis (APB), abductor digiti minimi (ADM), and across the APB-ADM muscles, which have been widely used for the mMEP in the upper extremities. METHODS Thirty right-handed patients were recruited in this prospective study. No patients showed any adverse events in their mMEP signals of the upper extremities during surgery. The mMEPs were recorded independently from the signals for the APB and ADM and for those across the APB-ADM. RESULTS The mMEP amplitude from across the APB-ADM was statistically higher than those recorded from the APB and ADM muscles. Moreover, the coefficient of variation of the mMEP amplitude from across the APB-ADM was smaller than those of mMEP amplitude recorded from the APB and ADM muscles. CONCLUSION The mMEP from across the APB-ADM muscles showed a high yield with high stability compared to those in each case from the APB and ADM muscles. The configuration across the APB-ADM muscles would be best for mMEP recordings from the upper extremities for intraoperative neurophysiological monitoring purposes.
Collapse
Affiliation(s)
- Young-Doo Choi
- Department of Neurosurgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Seung-Hyun Jin
- Department of Neurosurgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.,Neuroscience Research Institute, Seoul National University Medical Research Center, Seoul, Korea
| | - Chi-Heon Kim
- Department of Neurosurgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.,Neuroscience Research Institute, Seoul National University Medical Research Center, Seoul, Korea.,Department of Neurosurgery, Seoul National University College of Medicine, Seoul, Korea
| | - Gil Ho Kwak
- Department of Neurosurgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Bo Eun Kim
- Department of Neurosurgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Chun Kee Chung
- Department of Neurosurgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.,Neuroscience Research Institute, Seoul National University Medical Research Center, Seoul, Korea.,Department of Neurosurgery, Seoul National University College of Medicine, Seoul, Korea.,Department of Brain and Cognitive Sciences, Seoul National University College of Natural Sciences, Seoul, Korea
| |
Collapse
|
22
|
Abstract
Intraoperative motor evoked potentials include the D-wave as a surrogate for long-term motor outcome and muscle motor evoked potentials as a surrogate for early outcome. Their efficacy depends on excluding confounding factors and on warning criteria; insufficiently sensitive criteria could result in unpredicted deficits, whereas excessively sensitive ones could cause false alarms deterring surgical treatment and jading surgeons to alerts, eventually leading to deficits through failure to intervene. Although D-waves have few indications, they are nonsynaptic, linear, and stable-properties that support amplitude reduction criteria: >50% for intramedullary spinal cord tumor surgery and >30% to 40% for peri-Rolandic brain surgery. Muscle motor evoked potentials have many indications but are polysynaptic, nonlinear, and unstable-properties that challenge warning criteria and make them unusually capricious and sensitive. Disappearance is a remarkably frequent pathologic sign compared with other evoked potentials and is always a major criterion. Marked (>80%) amplitude reduction may be a minor or moderate spinal cord criterion, depending on the surgical circumstance. Modest (>50%) reduction may be a major criterion for brain, brainstem, and facial nerve monitoring, if justified by sufficient preceding stability. Acute ≥100-V threshold elevation may be a minor or moderate spinal cord criterion, depending on the surgical circumstance and on adherence to reported methodology. Morphology criteria lack support. Tailoring warning criteria to different monitoring situations based on anatomy, surgical goals, and published evidence seems advisable.
Collapse
|
23
|
Chen Y, Wang BP, Yang J, Deng Y. Neurophysiological monitoring of lumbar spinal nerve roots: A case report of postoperative deficit and literature review. Int J Surg Case Rep 2016; 30:218-221. [PMID: 28089323 PMCID: PMC5985246 DOI: 10.1016/j.ijscr.2016.11.027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 11/17/2016] [Accepted: 11/17/2016] [Indexed: 11/24/2022] Open
Abstract
INTRODUCTION Intraoperative neurophysiological monitoring (IONM) has proven to help reduce the probability of postoperative neurological deficit for spinal deformity correctional surgeries. However, in rare cases new deficits may still happen. We report a surgical case in which the patient had postoperative paralysis. We would like to call for more case reports with postoperative neurological deficits as they present difficult clinical cases. PRESENTATION OF CASE A 61-year-old male patient with severe thoracolumbar kyphoscoliosis underwent posterior spinal correction and fusion with segmental T10-L5 pedicle screws and rods instrumentation with IONM. The only intraoperative event was a pedicle breach at left L3 which was detected by triggered electromyography (EMG) testing, and the pedicle screw was repositioned. Left lower extremity paralysis was observed upon patient awakening. He received rehabilitation treatment and had limited recovery of muscle strength. Partial lumbar nerve root injury was likely the cause of the paralysis. DISCUSSION This is a case with new lumbar nerve root deficit, with positive EMG signal change, but negative somatosensory evoked potential (SSEP) and motor evoked potential (MEP) findings. We discuss the different neurophysiological modalities for monitoring lumbar spinal nerve root function. We review journal articles from the past two decades which reported lumbar root deficits, and list neuromonitoring events during the surgeries. CONCLUSION Multimodality monitoring with spontaneous and electrically triggered EMG combined with SSEP and MEP may provide the best chance to detect lumbar nerve root injuries.
Collapse
Affiliation(s)
- Yuguang Chen
- Department of Spinal Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Baoqing P Wang
- Neurological Monitoring Services, West Reading, PA, USA.
| | - Junlin Yang
- Department of Spinal Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Yaolong Deng
- Department of Spinal Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| |
Collapse
|
24
|
Abstract
The number of surgeries performed for adult spinal deformity (ASD) has been increasing due to an aging population, longer life expectancy, and studies supporting an improvement in health-related quality of life scores after operative intervention. However, medical and surgical complication rates remain high, and neurological complications such as spinal cord injury and motor deficits can be especially debilitating to patients. Several independent factors potentially influence the likelihood of neurological complications including surgical approach (anterior, lateral, or posterior), use of osteotomies, thoracic hyperkyphosis, spinal region, patient characteristics, and revision surgery status. The majority of ASD surgeries are performed by a posterior approach to the thoracic and/or lumbar spine, but anterior and lateral approaches are commonly performed and are associated with unique neural complications such as femoral nerve palsy and lumbar plexus injuries. Spinal morphology, such as that of hyperkyphosis, has been reported to be a risk factor for complications in addition to three-column osteotomies, which are often utilized to correct large deformities. Additionally, revision surgeries are common in ASD and these patients are at an increased risk of procedure-related complications and nervous system injury. Patient selection, surgical technique, and use of intraoperative neuromonitoring may reduce the incidence of complications and optimize outcomes.
Collapse
Affiliation(s)
- Justin A Iorio
- Spine Care Institute, Hospital for Special Surgery, 535 East 70th Street, New York, NY, 10021, USA.
| | - Patrick Reid
- Spine Care Institute, Hospital for Special Surgery, 535 East 70th Street, New York, NY, 10021, USA
| | - Han Jo Kim
- Spine Care Institute, Hospital for Special Surgery, 535 East 70th Street, New York, NY, 10021, USA
| |
Collapse
|
25
|
Raynor BL, Padberg AM, Lenke LG, Bridwell KH, Riew KD, Buchowski JM, Luhmann SJ. Failure of Intraoperative Monitoring to Detect Postoperative Neurologic Deficits: A 25-year Experience in 12,375 Spinal Surgeries. Spine (Phila Pa 1976) 2016; 41:1387-1393. [PMID: 26913466 DOI: 10.1097/brs.0000000000001531] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN Retrospective. OBJECTIVE The purpose was to categorize and evaluate intraoperative monitoring (IOM) failure to detect neurologic deficits occurring during spinal surgery. SUMMARY OF BACKGROUND DATA The efficacy of spinal cord/nerve root monitoring regarding undetected neurologic deficits is examined in a large, single institution series involving all levels of the spinal column and all spinal surgical procedures. METHODS Multimodality IOM included somatosensory-evoked potentials (SSEPs), descending neurogenic-evoked potentials (DNEPs), transcranial motor-evoked potentials (MEPs), dermatomal somatosensory-evoked potentials (DSEPs), and spontaneous and triggered electromyography (spEMG, trgEMG). We reviewed 12,375 patients who underwent surgery for spinal pathology from 1985 to 2010. There were 7178 females (59.3%) and 5197 males (40.7%); 9633 (77.8%) primary surgeries and 2742 (22.2%) revisions. Procedures by spinal level were cervical 29.7% (3671), thoracic/thoracolumbar 45.4% (5624), and lumbosacral 24.9% (3080). Age at surgery was > 18 years - 72.7% (8993) and < 18 years - 27.3% (3382). RESULTS Forty-five of the 12,375 patients (0.36%) had false negative outcomes. False negative results by modality were as follows: spEMG (n = 22, 48.8%), trgEMG (n = 8, 17.7%), DSEP (n = 4, 8.8%), DNEP (n = 4, 8.8%), SSEP (n = 3, 6.6%), DSEP/spEMG (n = 3, 6.6%), and trgEMG/spEMG (n = 1, 2.2%). Thirty-seven patients had immediate postoperative deficits unidentified by IOM; 30 patients (81%) involved nerve root monitoring, four patients had spinal cord deficits, and three patients had peripheral sensory deficits. Eight patients had permanent neurologic deficits, six (0.048%) were nerve root and two (0.016%) were spinal cord in nature. CONCLUSION Despite correct application and usage, IOM data failed to identify 45 (0.36%) patients with false negative outcomes out of 12,375 surgical patients. Eight patients (0.064%) of these 45 patients had permanent neurologic deficits, six patients had nerve root deficits in nature and two patients had spinal cord deficits. Although admittedly small, this represents the risk of undetected neurologic deficits even when properly using IOM. Deficits are at a higher risk to remain unresolved when not detected by IOM. LEVEL OF EVIDENCE 4.
Collapse
Affiliation(s)
- Barry L Raynor
- Intraoperative Monitoring Service, Barnes-Jewish Hospital, Saint Louis, MO
| | - Anne M Padberg
- Intraoperative Monitoring Service, Barnes-Jewish Hospital, Saint Louis, MO
| | - Lawrence G Lenke
- Department of Orthopedic Surgery, The Spine Hospital, Columbia University Medical Center, New York, NY
| | - Keith H Bridwell
- Department of Orthopedic Surgery, Washington University School of Medicine, Saint Louis, MO
| | - K Daniel Riew
- Department of Orthopedic Surgery, The Spine Hospital, Columbia University Medical Center, New York, NY
| | - Jacob M Buchowski
- Department of Orthopedic Surgery, Washington University School of Medicine, Saint Louis, MO
| | - Scott J Luhmann
- Department of Orthopedic Surgery, Washington University School of Medicine, Saint Louis, MO
| |
Collapse
|
26
|
Tsutsui S, Yamada H. Basic Principles and Recent Trends of Transcranial Motor Evoked Potentials in Intraoperative Neurophysiologic Monitoring. Neurol Med Chir (Tokyo) 2016; 56:451-6. [PMID: 26935781 PMCID: PMC4987444 DOI: 10.2176/nmc.ra.2015-0307] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Transcranial motor evoked potentials (TcMEPs), which are muscle action potentials elicited by transcranial brain stimulation, have been the most popular method for the last decade to monitor the functional integrity of the motor system during surgery. It was originally difficult to record reliable and reproducible potentials under general anesthesia, especially when inhalation-based anesthetic agents that suppressed the firing of anterior horn neurons were used. Advances in anesthesia, including the introduction of intravenous anesthetic agents, and progress in stimulation techniques, including the use of pulse trains, improved the reliability and reproducibility of TcMEP responses. However, TcMEPs are much smaller in amplitude compared with compound muscle action potentials evoked by maximal peripheral nerve stimulation, and vary from one trial to another in clinical practice, suggesting that only a limited number of spinal motor neurons innervating the target muscle are excited in anesthetized patients. Therefore, reliable interpretation of the critical changes in TcMEPs remains difficult and controversial. Additionally, false negative cases have been occasionally encountered. Recently, several facilitative techniques using central or peripheral stimuli, preceding transcranial electrical stimulation, have been employed to achieve sufficient depolarization of motor neurons and augment TcMEP responses. These techniques might have potentials to improve the reliability of intraoperative motor pathway monitoring using TcMEPs.
Collapse
Affiliation(s)
- Shunji Tsutsui
- Department of Orthopedic Surgery, Wakayama Medical University
| | | |
Collapse
|
27
|
Rabai F, Sessions R, Seubert CN. Neurophysiological monitoring and spinal cord integrity. Best Pract Res Clin Anaesthesiol 2015; 30:53-68. [PMID: 27036603 DOI: 10.1016/j.bpa.2015.11.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Revised: 11/10/2015] [Accepted: 11/17/2015] [Indexed: 12/15/2022]
Abstract
An integral part of a major spine surgery is the intraoperative neurophysiological monitoring (IONM). By providing continuous functional assessment of specific anatomic structures, IONM allows the rapid detection of neuronal compromise and the opportunity for corrective action before an insult causes permanent neurological damage. Thus, IONM functions not just as a diagnostic tool but may also improve surgical outcomes. Effective clinical application requires a thorough understanding of the scope and limitations of IONM modalities not only by the monitoring team but also by the surgeon and anesthesiologist. Intraoperatively, collaboration and communication between monitorist, surgeon, and anesthesiologist are critical to the effectiveness of IONM. In this study, we review specific monitoring modalities, focusing on the relevant anatomy, physiology, and mechanisms of neuronal injury during major spine surgery. We discuss how these factors interact with anesthetic and surgical management. This review concludes with the current controversies surrounding the evidence in support of IONM and directions of future research.
Collapse
Affiliation(s)
- Ferenc Rabai
- Department of Anesthesiology, University of Florida College of Medicine, PO Box 100254 JHMHSC, 1600 SW Archer Rd., Room M-509, Gainesville, FL 32610-0254, USA.
| | - Renard Sessions
- Department of Anesthesiology, University of Florida College of Medicine, PO Box 100254 JHMHSC, 1600 SW Archer Rd., Room M-509, Gainesville, FL 32610-0254, USA.
| | - Christoph N Seubert
- Department of Anesthesiology, University of Florida College of Medicine, PO Box 100254 JHMHSC, 1600 SW Archer Rd., Room M-509, Gainesville, FL 32610-0254, USA.
| |
Collapse
|
28
|
Chaudhary K, Speights K, McGuire K, White AP. Re: Trans-cranial motor evoked potential detection of femoral nerve injury in trans-psoas lateral lumbar interbody fusion by Justin W. Silverstein. J Clin Monit Comput 2015; 30:745-6. [PMID: 26429133 DOI: 10.1007/s10877-015-9783-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 09/09/2015] [Indexed: 11/24/2022]
Affiliation(s)
- Kshitij Chaudhary
- Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | | | - Kevin McGuire
- Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | - Andrew P White
- Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA.
| |
Collapse
|
29
|
Holdefer RN, McAuliffe J, Seubert CN, MacDonald DB, Shils JL, Edwards ME, Cohen BA, Sturm PF. Intraoperative neuromonitoring for the prevention of iatrogenic injury during cervical and thoracic spine surgery. Hippokratia 2015. [DOI: 10.1002/14651858.cd011835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Robert N Holdefer
- University of Washington School of Medicine; Department of Rehabilitation; Box 359740 Seattle WA USA 98104-2499
| | - John McAuliffe
- Cincinnati Children's Hospital Medical Center; Department of Anesthesiology; 3333 Burnet Avenue E3-238 Cincinnati Ohio USA 45229-3039
| | - Christoph N Seubert
- University of Florida College of Medicine; Director, Intraoperative Neurologic Monitoring Laboratory, Shands at UF; Gainesville FL USA
| | - David B MacDonald
- King Faisal Specialist Hospital & Research Center; Department of Neurosciences; MBC 76, PO Box 3354 Riyadh Saudi Arabia 11211
| | - Jay L Shils
- Rush University Medical Center; Department of Anesthesiology; 1750 W. Harrison (Suite 739 jelke) Chicago IL USA 60612
| | - Mary E Edwards
- University of Florida; University of Florida Health Science Center Libraries; 1600 SW Archer Road PO Box 100206 Gainesville Florida USA 32610-0206
| | - Bernard A Cohen
- Neurological Monitoring Associates, LLC; 333 West Brown Deer Road Suite 240 Milwaukee WI USA 53217
| | - Peter F Sturm
- Cincinnati Children's Hospital Medical Center; 3333 Burnet Avenue ML2017 Cincinnati OH USA 45229
| |
Collapse
|
30
|
Trans-cranial motor evoked potential detection of femoral nerve injury in trans-psoas lateral lumbar interbody fusion. J Clin Monit Comput 2015; 29:549-54. [PMID: 26076805 DOI: 10.1007/s10877-015-9713-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Accepted: 06/05/2015] [Indexed: 10/23/2022]
Abstract
Trans-psoas lateral lumbar interbody fusion (LLIF) is frequently associated with neurological complications, limiting its value as a less invasive procedure. The routine use of EMG neuromonitoring has been inadequate to detect iatrogenic injuries; significant postoperative deficits have gone undetected by EMG. An effective way to monitor for these intraoperative neurological events is not yet well established. To our knowledge, detection of lumbar plexus injury during LLIF by trans-cranial motor evoked potentials (MEP) without corresponding change in EMG has not been reported in the literature. Three cases are presented to illustrate the potential utility of trans-cranial MEP monitoring during trans-psoas LLIF. We introduce a modified intraoperative neuro-monitoring (IONM) protocol for LLIF surgery, which includes MEP in addition to spontaneous and triggered EMG. Postoperative neurological outcome was correlated with the IONM findings. In each case, loss of quadriceps MEP signals occurred during LLIF at L4/L5, and after prolonged retraction (27, 25 and 61 min respectively). The EMG, however, did not show any abnormal activity. Two patients had post-operative quadriceps weakness, concordant with MEP data. The third patient, in whom the MEP signals returned to normal after expeditious removal of the retractor, did not exhibit quadriceps weakness, also concordant with MEP data. These cases contribute to the developing perception that stand-alone EMG nerve monitoring is not adequate for trans-psoas surgery. The addition of MEP may improve the sensitivity of IONM during trans-psoas surgery. Multimodality IONM may offer the opportunity to intervene on evolving iatrogenic nerve injuries, and may reduce the incidence of adverse postoperative findings.
Collapse
|
31
|
Somatosensory and motor evoked potentials as biomarkers for post-operative neurological status. Clin Neurophysiol 2015; 126:857-65. [DOI: 10.1016/j.clinph.2014.11.009] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 11/07/2014] [Accepted: 11/12/2014] [Indexed: 11/22/2022]
|
32
|
Abstract
Intraoperative neurophysiologic monitoring has had major advances in the past few decades. During spine surgery, the use of multimodality monitoring enables us to assess the integrity of the spinal cord, nerve roots, and peripheral nerves. The authors present a practical approach to the current modalities in use during spine surgery, including somatosensory evoked potentials, motor evoked potentials, spinal D-waves, and free-run and triggered electromyography. Understanding the complementary nature of these modalities will help tailor monitoring to a particular procedure to minimize postoperative neurologic deficit during spine surgery.
Collapse
|
33
|
|
34
|
Tsutsui S, Iwasaki H, Yamada H, Hashizume H, Minamide A, Nakagawa Y, Nishi H, Yoshida M. Augmentation of motor evoked potentials using multi-train transcranial electrical stimulation in intraoperative neurophysiologic monitoring during spinal surgery. J Clin Monit Comput 2014; 29:35-9. [PMID: 24532184 DOI: 10.1007/s10877-014-9565-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2013] [Accepted: 02/12/2014] [Indexed: 11/30/2022]
Abstract
Transcranial motor evoked potentials (TcMEPs) are widely used to monitor motor function during spinal surgery. Improvements in transcranial stimulation techniques and general anesthesia have made it possible to record reliable and reproducible potentials. However, TcMEPs are much smaller in amplitude compared with compound muscle action potentials (CMAPs) evoked by maximal peripheral nerve stimulation. In this study, multi-train transcranial electrical stimulation (mt-TES) was introduced to enhance TcMEPs, and the optimal setting of mt-TES was investigated. In 30 patients undergoing surgical correction of spinal deformities (4 males and 26 females with normal motor status; age range 11-75 years), TcMEPs from the abductor hallucis (AH) and quadriceps femoris (QF) were analyzed. A multipulse (train) stimulus with an individual pulse width of 0.5 ms and an inter-pulse interval of 2 ms was delivered repeatedly (2-7 times) at different rates (2, 5, and 10 Hz). TcMEP amplitudes increased with the number of train stimuli for AH, with the strongest facilitation observed at 5 Hz. The response amplitude increased 6.1 times on average compared with single-train transcranial electrical stimulation (st-TES). This trend was also observed in the QF. No adverse events (e.g., seizures, cardiac arrhythmias, scalp burns, accidental injury resulting from patient movement) were observed in any patients. Although several facilitative techniques using central or peripheral stimuli, preceding transcranial electrical stimulation, have been recently employed to augment TcMEPs during surgery, responses are still much smaller than CMAPs. Changing from conventional st-TES to mt-TES has potential to greatly enhance TcMEP responses.
Collapse
Affiliation(s)
- Shunji Tsutsui
- Department of Orthopaedic Surgery, Wakayama Medical University, 811-1 Kimiidera, Wakayama, 641-8510, Japan,
| | | | | | | | | | | | | | | |
Collapse
|
35
|
|
36
|
Effect of Hemorrhage and Hypotension on Transcranial Motor-evoked Potentials in Swine. Anesthesiology 2013; 119:1109-19. [DOI: 10.1097/aln.0b013e31829d4a92] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Abstract
Background:
Transcranial motor-evoked potentials (TcMEPs) monitor spinal cord motor tract integrity. Using a swine model, the authors studied the effects of vasodilatory hypotension, hemorrhage, and various resuscitation efforts on TcMEP responses.
Methods:
Twelve pigs were anesthetized with constant infusions of propofol, ketamine, and fentanyl. Animals were incrementally hemorrhaged, until bilateral tibialis anterior TcMEP amplitude decreased to less than 40% of baseline or until 50% of the blood volume was removed. Mean arterial pressure (MAP), cardiac output (CO), and oxygen delivery (DO2) were examined. Resuscitation with phenylephrine, epinephrine, and colloid were evaluated. In seven animals, vasodilatory hypotension was examined. Paired comparisons and multivariate analysis were performed.
Results:
Hemorrhage significantly reduced (as a percentage of baseline, mean ± SD) TcMEPs (left, 33 ± 29%; right, 26 ± 21%), MAP (60 ± 17%), CO (49 ± 12%), and DO2 (43 ± 13%), P value less than 0.001 for all. Vasodilation reduced MAP comparably, but TcMEPs, CO, and DO2, were not significantly lowered. After hemorrhage, restoration of MAP with phenylephrine did not improve TcMEPs, CO, or DO2, but similar restoration of MAP with epinephrine restored (to percentage of baseline) TcMEPs (59 ± 40%), and significantly increased CO (81 ± 17%) and DO2 (72 ± 19%) compared with both hemorrhage and phenylephrine, P value less than 0.05 for all. Resuscitation with colloid did not improve TcMEPs. Multivariate analysis revealed that changes in TcMEPs were more closely associated with changes in CO and DO2 as compared with MAP.
Conclusions:
Hypotension from hemorrhage, but not vasodilation, is associated with a decrease in TcMEP amplitude. After hemorrhage, restoration of TcMEPs with epinephrine but not phenylephrine indicates that CO and DO2 affect TcMEPs more than MAP. Monitoring CO may be beneficial in major spine surgery when using TcMEP monitoring.
Collapse
|
37
|
Macdonald DB, Skinner S, Shils J, Yingling C. Intraoperative motor evoked potential monitoring - a position statement by the American Society of Neurophysiological Monitoring. Clin Neurophysiol 2013; 124:2291-316. [PMID: 24055297 DOI: 10.1016/j.clinph.2013.07.025] [Citation(s) in RCA: 302] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2013] [Revised: 07/20/2013] [Accepted: 07/22/2013] [Indexed: 12/12/2022]
Abstract
The following intraoperative MEP recommendations can be made on the basis of current evidence and expert opinion: (1) Acquisition and interpretation should be done by qualified personnel. (2) The methods are sufficiently safe using appropriate precautions. (3) MEPs are an established practice option for cortical and subcortical mapping and for monitoring during surgeries risking motor injury in the brain, brainstem, spinal cord or facial nerve. (4) Intravenous anesthesia usually consisting of propofol and opioid is optimal for muscle MEPs. (5) Interpretation should consider limitations and confounding factors. (6) D-wave warning criteria consider amplitude reduction having no confounding factor explanation: >50% for intramedullary spinal cord tumor surgery, and >30-40% for peri-Rolandic surgery. (7) Muscle MEP warning criteria are tailored to the type of surgery and based on deterioration clearly exceeding variability with no confounding factor explanation. Disappearance is always a major criterion. Marked amplitude reduction, acute threshold elevation or morphology simplification could be additional minor or moderate spinal cord monitoring criteria depending on the type of surgery and the program's technique and experience. Major criteria for supratentorial, brainstem or facial nerve monitoring include >50% amplitude reduction when warranted by sufficient preceding response stability. Future advances could modify these recommendations.
Collapse
Affiliation(s)
- D B Macdonald
- Section of Clinical Neurophysiology, Department of Neurosciences, King Faisal Specialist Hospital & Research Center, MBC 76, PO Box 3354, Riyadh, Saudi Arabia.
| | | | | | | | | |
Collapse
|
38
|
|