scholarly journals Motor Evoked Potentials and Disability in Secondary Progressive Multiple Sclerosis

1997 ◽  
Vol 24 (04) ◽  
pp. 332-337 ◽  
Author(s):  
D. Facchetti ◽  
R. Mai ◽  
A. Micheli ◽  
N. Marcianó ◽  
R. Capra ◽  
...  
Keyword(s):  
Evoked Potentials ◽  
Lower Limb ◽  
Evoked Potential ◽  
Motor Evoked Potentials ◽  
Functional System ◽  
Conduction Time ◽  
Lesion Load ◽  
Secondary Progressive ◽  
Spinal Motor ◽  
Relapsing Remitting

ABSTRACT:Background:To investigate the mechanisms underlying disability in multiple sclerosis (MS), 40 patients with the relapsing-remitting form of the disease and 13 patients with secondary progressive MS underwent multimodal evoked potential (EP), motor evoked potential (MEP), and spinal motor conduction time evaluation. Clinical disability was evaluated by the expanded disability status scale (EDSS) and functional system scales. In secondary progressive MS patients, magnetic resonance imaging (MRI) was used to obtain a semiquantitative estimate of the total lesion load of the brain.Results:Spinal motor conduction time was significantly longer in secondary progressive MS patients than controls (p < 0.001) and relapsing-remitting MS patients (p < 0.05), but did not differ between relapsing-remitting patients and controls. Spinal motor conduction times also correlated directly with EDSS scores (p < 0.001) and pyramidal functional system scores (p < 0.001). Brain lesion load (4960.3 ± 3719.0 mm2) and the total number of lesions (67.7 ± 37.0) in secondary progressive MS did not correlate with disability scores. For the following EPs, the frequencies of abnormalities were significantly higher in secondary progressive MS patients than relapsing-remitting patients: visual evoked potentials (p < 0.05), somatosensory evoked potentials and upper limb motor evoked potentials (p < 0.01), and brainstem auditory evoked potentials, lower limb somatosensory evoked potentials and lower limb motor evoked potentials (p < 0.001).Conclusions:These findings suggest that disability in secondary progressive MS patients is mainly due to progressive involvement of corticospinal tract in the spinal cord.

031 Investigating motor evoked potentials as a biomarker for disease severity in hereditary spastic paraplegia

2018 ◽  
Vol 89 (6) ◽  
pp. A13.2-A13
Author(s):  
Sue-Faye Siow ◽  
Carolyn Sue ◽  
Kishore Kumar ◽  
Sharon Coward ◽  
Amy Lofts ◽  
...  
Keyword(s):  
Evoked Potentials ◽  
Disease Severity ◽  
Lower Limb ◽  
Hereditary Spastic Paraplegia ◽  
Disease Duration ◽  
Rating Scale ◽  
Motor Evoked Potentials ◽  
Conduction Time ◽  
Spastic Paraplegia ◽  
Resting Motor Threshold

IntroductionHereditary spastic paraplegia (HSP) encompasses a diverse group of neurodegenerative disorders that results in significant disability with no curative or disease-modifying treatment. The lack of standardised biomarkers of disease severity has limited the evaluation of potential therapeutic agents. Our aim is to investigate motor evoked potentials (MEPs) as a marker of HSP disease severity.MethodsWe studied 21 subjects (10 male, 11 female; mean age 54.3±13.8 years) with a clinical diagnosis of HSP (10 SPG4, 4 SPG7, 1 SPG3A, 1 SPG 30, 5 genetically undetermined). All patients underwent transcranial magnetic stimulation to measure central motor conduction time (CMCT), resting motor threshold (rMT) and MEP amplitude from the tibialis anterior (TA), abductor hallucis (AH) and abductor digiti minimi (ADM). Clinical disease severity was assessed with the Spastic Paraplegia Rating Scale (SPRS). Pearson correlation coefficient was used to assess correlation between variables, significance was defined as P value<0.05.ResultsTA CMCT was prolonged in 16/21 subjects (76%). AH CMCT was absent in 3/18 subjects (16.7%) and prolonged in 9/18 subjects (50%). ADM CMCT was measured in 19 subjects; all were normal. There was no significant correlation between SPRS scores and MEP amplitude, rMT or CMCT for TA or AH. There was also no significant correlation between these MEP measures and disease duration or patient age. Subgroup analysis of SPG4 HSP (10 subjects) revealed significant correlation between TA and AH CMCT with disease duration (r=0.841, p=0.001; r=0.930, p=0.001) but not SPRS scores.ConclusionLower limb CMCT was absent or prolonged in the majority of subjects. Despite being potentially useful as a diagnostic biomarker for HSP, this study only showed a correlation between lower limb CMCT and disease duration in the SPG4 subgroup. Further genotype-specific studies utilising larger numbers may clarify the relationship between MEP markers and clinical features.

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

2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Davide Giampiccolo ◽  
Cristiano Parisi ◽  
Pietro Meneghelli ◽  
Vincenzo Tramontano ◽  
Federica Basaldella ◽  
...  
Keyword(s):  
Evoked Potentials ◽  
Brain Tumour ◽  
Evoked Potential ◽  
Corticospinal Tract ◽  
Motor Evoked Potentials ◽  
Motor Evoked Potential ◽  
Motor Deficit ◽  
Motor Deficits ◽  
Brain Tumour Surgery

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

scholarly journals Clinical, Neurophysiological, and MRI Markers of Fampridine Responsiveness in Multiple Sclerosis—An Explorative Study

2021 ◽  
Vol 12 ◽  
Author(s):  
Sepehr Mamoei ◽  
Henrik Boye Jensen ◽  
Andreas Kristian Pedersen ◽  
Mikkel Karl Emil Nygaard ◽  
Simon Fristed Eskildsen ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Longitudinal Study ◽  
Transcranial Magnetic Stimulation ◽  
Magnetic Stimulation ◽  
Motor Evoked Potentials ◽  
Step Test ◽  
Conduction Time ◽  
Lesion Load ◽  
Clinical Trial Registration ◽  
Peripheral Motor

Objective: Persons with multiple sclerosis (PwMS), already established as responders or non-responders to Fampridine treatment, were compared in terms of disability measures, physical and cognitive performance tests, neurophysiology, and magnetic resonance imaging (MRI) outcomes in a 1-year explorative longitudinal study.Materials and Methods: Data from a 1-year longitudinal study were analyzed. Examinations consisted of the timed 25-foot walk test (T25FW), six spot step test (SSST), nine-hole peg test (9-HPT), five times sit-to-stand test (5-STS), symbol digit modalities test (SDMT), transcranial magnetic stimulation (TMS) elicited motor evoked potentials (MEP) examining central motor conduction times (CMCT), peripheral motor conduction times (PMCT) and their amplitudes, electroneuronography (ENG) of the lower extremities, and brain structural MRI measures.Results: Forty-one responders and eight non-responders to Fampridine treatment were examined. There were no intergroup differences except for the PMCT, where non-responders had prolonged conduction times compared to responders to Fampridine. Six spot step test was associated with CMCT throughout the study. After 1 year, CMCT was further prolonged and cortical MEP amplitudes decreased in both groups, while PMCT and ENG did not change. Throughout the study, CMCT was associated with the expanded disability status scale (EDSS) and 12-item multiple sclerosis walking scale (MSWS-12), while SDMT was associated with number of T2-weighted lesions, lesion load, and lesion load normalized to brain volume.Conclusions: Peripheral motor conduction time is prolonged in non-responders to Fampridine when compared to responders. Transcranial magnetic stimulation-elicited MEPs and SDMT can be used as markers of disability progression and lesion activity visualized by MRI, respectively.Clinical Trial Registration:www.ClinicalTrials.gov, identifier: NCT03401307.

Natalizumab restores evoked potential abnormalities in patients with relapsing–remitting multiple sclerosis

2010 ◽  
Vol 17 (2) ◽  
pp. 198-203 ◽  
Author(s):  
Sven G Meuth ◽  
Stefan Bittner ◽  
Carola Seiler ◽  
Kerstin Göbel ◽  
Heinz Wiendl
Keyword(s):  
Multiple Sclerosis ◽  
Evoked Potentials ◽  
Motor Evoked Potentials ◽  
Sum Score ◽  
Relapsing Remitting ◽  
Natalizumab Treatment ◽  
Remitting Multiple Sclerosis ◽  
Sum Scores ◽  
Multiple Sclerosis Patients ◽  
Relapsing Remitting Multiple Sclerosis

Background and Objective: The objective of this study was to examine the effects of natalizumab on functional parameters assessed by evoked potentials (visual [VEP], somatosensory [SEP] and motor evoked potentials [MEP]) in a cohort study in relapsing–remitting multiple sclerosis patients. Methods: EP data of 44 patients examined 12 months prior to natalizumab treatment, at the timepoint of treatment initiation and 1 year later were compared. Sum scores (VEP, MEP, SEP) were evaluated and correlated with the Expanded Disability Status Scale. Results: Improvement of the VEP sum score was found in 33% of natalizumab-treated patients but only in 9% of the same patients prior to treatment ( p = 0.041). A comparable situation was found for SEP (improvement: 32% versus 5%; worsening: 11% versus 37%; p = 0.027). For MEP no significant differences were seen (improvement: 10% versus 18%; worsening: 5% versus 29%; p = 0.60). EP recordings (VEP = SEP > MEP) have the capacity to demonstrate treatment effects of natalizumab on a functional level. Conclusions: Natalizumab therapy increases the percentage of patients showing stable or even ameliorated electrophysiological parameters in the investigated functional systems.

Loss of Lower Limb Motor Evoked Potentials and Spinal Cord Injury During the Initial Exposure in Scoliosis Surgery

2014 ◽  
Vol 31 (2) ◽  
pp. e1-e5 ◽  
Author(s):  
Alan D. Legatt ◽  
Stephen J. Fried ◽  
Terry D. Amaral ◽  
Vishal Sarwahi ◽  
Marina Moguilevitch
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Evoked Potentials ◽  
Lower Limb ◽  
Motor Evoked Potentials ◽  
Scoliosis Surgery ◽  
Initial Exposure ◽  
Cord Injury

scholarly journals Peculiarities of motor evoked potential in healthy children of different age

2019 ◽  
Vol 19 (4) ◽  
pp. 228-231
Author(s):  
Vladislav B. Voitenkov ◽  
N. V. Skripchenko ◽  
A. V. Klimkin ◽  
A. I. Aksenova
Keyword(s):  
Normative Data ◽  
Evoked Potential ◽  
Motor Evoked Potentials ◽  
Pediatric Population ◽  
Motor Evoked Potential ◽  
Conduction Time ◽  
Healthy Children ◽  
Abductor Hallucis ◽  
Abductor Pollicis Brevis ◽  
Pediatric Disorders

Aim of the work The implementation of the database for reference values of motor evoked potentials (MEP) in healthy children of different ages. Methods 95 healthy children were enrolled. Age ranged from 1 to 204 months. Three subgroups were established: children of 1-12 months (n=31, 18 males, 13 females), 12-144 months (n=27, 14 males, 13 females) and 144-204 (n=37, 20 males, 17 females) months. All children were healthy. Diagnostic transcranial magnetic stimulation (TMS) was performed in all patients. MEP shape, threshold, latency and amplitudes were recorded for hands (m. Abductor pollicis brevis) and legs (m. Abductor Hallucis). Central motor conduction time (CMCT) was calculated. Results. Along with age there was observed the elongation of MEP latency, gain in amplitudes and shape normalization. There were significant differences in the elongation of MEP latency between children aged of 1-12 months and children from two other subgroups (12-144 and 144-204 months). Conclusions. Our normative data can be usedfor comparative studies in the broad spectrum of pediatric disorders. Age restrictions have to be taken in a consideration when performing the TMS in pediatric population.

Motor evoked potentials in clinically isolated syndrome suggestive of multiple sclerosis

2009 ◽  
Vol 15 (3) ◽  
pp. 355-362 ◽  
Author(s):  
A Rico ◽  
B Audoin ◽  
J Franques ◽  
A Eusebio ◽  
F Reuter ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Evoked Potentials ◽  
Amplitude Ratio ◽  
Motor Evoked Potentials ◽  
Clinically Isolated Syndrome ◽  
Conduction Time ◽  
Motor Pathway ◽  
Clinical Sensitivity ◽  
Conduction Failure ◽  
Stimulation Technique

The aim of the present study was to determine the sensitivity and the profile of motor evoked potentials (MEP) in patients with clinically isolated syndrome (CIS) suggestive of multiple sclerosis (MS). We measured the central motor conduction time (CMCT), amplitude ratio (AR), and surface ratio (SR) in tibialis anterior and first dorsal interosseous muscles in 22 patients with CIS. In 12 patients, the triple stimulation technique (TST) was also performed. AR was abnormal in 50% of patients, CMCT in 18% of patients, and TST in 25% of patients. AR had the highest sub-clinical sensitivity and the best positive predictive value. In the absence of clinical pyramidal signs, an early AR decrease seems to result from demyelination inducing excessive temporal dispersion of the MEP, while in territories with clinical pyramidal signs, it seems to result from conduction failure, which suggests that clinical pyramidal signs may be attributable to conduction failure. This study demonstrates that MEP, especially the AR, is sensitive to motor pathway dysfunction right from the early stages of MS.

Determining the Corticospinal and Neuromuscular Responses Following a Warm-Up Protocol

2020 ◽  
Vol 2 (2) ◽  
pp. 1-12
Author(s):  
Rhys Painter ◽  
Alan Pearce ◽  
Mohamad Rostami ◽  
Ashlyn Frazer ◽  
Dawson Kidgell
Keyword(s):  
Heart Rate ◽  
Evoked Potentials ◽  
Neuromuscular Transmission ◽  
Primary Motor Cortex ◽  
Motor Evoked Potentials ◽  
Corticospinal Excitability ◽  
Muscle Temperature ◽  
Conduction Time ◽  
Warm Up ◽  
Time To Peak

Background: The effect of warming-up prior to exercise on increased neuromuscular transmission speed remains largely untested. Objective: This study used transcranial magnetic stimulation (TMS) and peripheral nerve stimulation (PNS) to quantify neuromuscular transmission along the corticospinal tract (CST) before and after a warm-up protocol of the elbow flexors. Method: Using a single-group, pre-test-post-test design, 30 participants (20 male; 10 female; mean age 26.3 ± 7.4 years) completed four sets of bicep curls that aimed to increase heart rate (HR) and biceps brachii (BB) muscle temperature by a minimum of 40 beats per minute (bpm) and 1°C, respectively. Single-pulse TMS was applied to the primary motor cortex, and over the cervical and thoracic (C7-T1) areas of the spine to quantify motor evoked potentials (MEPs) and spinal evoked potentials (SEPs), respectively. Central motor conduction time (CMCT) was determined by calculating the difference in latency time of the onset of MEPs and SEPs. Peripheral motor conduction time (PMCT) was calculated following stimuli from Erb’s point to the onset of the maximal compound muscle action potential twitch (MMAX latency). MMAX time to peak twitch was also measured. MMAX amplitude was used to normalize the MEP to quantify corticospinal excitability. Results: Following the warm-up, significant increases in mean heart rate (44.8 ± 11.7 bpm; P < 0.001) and muscle temperature (1.4 ± 0.6°C; P < 0.001) were observed. No changes were seen in corticospinal excitability (P = 0.39), CMCT (P = 0.09), or MMAX latency (P = 0.24). However, MMAX time to peak twitch was significantly reduced (P = 0.003). Conclusion: This study has shown that exercise-based warm-ups improve neuromuscular conduction velocity via thermoregulatory processes that result in the onset of muscle contraction being more rapid, but not as a result of changes in the efficacy of neural transmission along the CST.

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