Journal of Clinical Neurophysiology最新文献

{"title":"Agreement and Consistency of Absolute and Relative Corticospinal Stimulus-Response Curves for Upper, Lower, and Axial Musculature in Healthy Adults.","authors":"Juliana R Hougland, Felix Proessl, Nicholas Meglino, Maria C Canino, Adam J Sterczala, Chris Connaboy, Bradley C Nindl, Shawn D Flanagan","doi":"10.1097/WNP.0000000000001109","DOIUrl":"10.1097/WNP.0000000000001109","url":null,"abstract":"<p><strong>Purpose: </strong>To assess the agreement and consistency of absolute and relative stimulus-response curve (SRC) parameter estimates for upper extremity, lower extremity, and axial muscles.</p><p><strong>Methods: </strong>Thirty (15 W, age: 27.0 ± 6.3 y, height: 171.9 ± 8.9 cm, weight: 80.2 ± 19.3 kg) healthy adults completed absolute (5% to 100% stimulator output) and relative (65% to 160% motor threshold) SRCs of the first dorsal interosseous, vastus lateralis, and rectus abdominis during submaximal isometric contractions. Mean motor-evoked potential amplitudes were fit with nonlinear regression to derive MEP max , V 50 , and slope. Absolute agreement and consistency were assessed with ICCs, Cronbachs alphas, and Bland-Altman plots. Independent t -tests were used to examine differences in motor threshold, physical activity, strength, and muscle activity among participants with valid and invalid SRC parameters.</p><p><strong>Results: </strong>Absolute and relative SRCs displayed good agreement and consistency for MEP max and V 50 but not slope. Motor thresholds were lower among participants with valid absolute SRCs for the rectus abdominis and vastus lateralis. Motor threshold, physical activity, strength, and muscle activity did not differ among those with valid and invalid parameters for all relative SRCs and absolute SRCs for the first dorsal interosseous.</p><p><strong>Conclusions: </strong>Absolute and relative SRCs produce similar MEP max and V 50 estimates in the first dorsal interosseous, vastus lateralis, and rectus abdominis. The validity of absolute and relative SRC results may differ depending on individual characteristics and tested muscles.</p>","PeriodicalId":15516,"journal":{"name":"Journal of Clinical Neurophysiology","volume":" ","pages":"264-271"},"PeriodicalIF":2.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141874971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Fingerprint of Scalp-EEG in Drug-Resistant Frontal Lobe Epilepsies.","authors":"Gudrun Kalss, Veronica Pelliccia, Georg Zimmermann, Eugen Trinka, Laura Tassi","doi":"10.1097/WNP.0000000000001106","DOIUrl":"10.1097/WNP.0000000000001106","url":null,"abstract":"<p><strong>Purpose: </strong>Scalp-EEG incompletely covers the frontal lobe cortex. Underrepresentation of frontobasal or frontomesial structures, fast ictal spreading, and false lateralization impede scalp-EEG interpretation. Hence, we investigated the significance of scalp-EEG in the presurgical workup of frontal lobe epilepsy.</p><p><strong>Methods: </strong>Using descriptive statistical methods and Pearson chi-squared test for group comparisons, we retrospectively investigated postsurgical outcome, interictal epileptiform discharges (iiEDs), and electrographic seizure patterns on scalp-EEG in 81 consecutive patients undergoing resective epilepsy surgery within the margins of the frontal lobe.</p><p><strong>Results: </strong>Postoperatively, patients with frontopolar iiEDs ( n = 7) or concordant frontopolar iiED focus and seizure-onset ( n = 2) were seizure free ( n = 7/7, Engel Ia). MRI-positive patients with frontopolar iiEDs or frontopolar seizure-onset ( n = 1/8 Engel Id, n = 7/8 Engel Ia) underwent surgery without stereo-EEG. Thirteen of 16 patients with frontolateral ( n = 8/10, Engel Ia), or left frontobasal ( n = 5/6, Engel Ia) seizure-onset undergoing further stereo-EEG, were seizure-free postoperatively. Seizure-onset prevalent over one electrode ( n = 37/44 Engel I, p = 0.02), fast activity (FA)/flattening at seizure-onset ( n = 29/33 Engel I, p = 0.02), FA/flattening during the seizure ( n = 38/46 Engel I, p = 0.05), or focal rhythmic sharp-/spike-/polyspike-and-slow waves during the seizure ( n = 24/31, Engel Ia, p = 0.05) were favorable prognostic markers. Interictal polyspike waves ( p = 0.006 for Engel Ia) and interictal paroxysmal FA ( p = 0.02 for Engel I) were unfavorable prognostic markers.</p><p><strong>Conclusions: </strong>Frontopolar scalp-EEG findings serve as biomarkers for predicting favorable surgical outcome in lesional frontal lobe epilepsy. Consequently, careful analysis of scalp-EEG assists in bypassing stereo-EEG in these patients.</p>","PeriodicalId":15516,"journal":{"name":"Journal of Clinical Neurophysiology","volume":" ","pages":"215-223"},"PeriodicalIF":2.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11864044/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141748279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Role of Intraoperative Neurophysiologic Monitoring on Surgical Decision Making and Neurologic Outcomes in Pediatric Patients With Intramedullary Spinal Cord Tumors.","authors":"Joanna E Papadakis, Amanda Mosher, Anna L Slingerland, John S Albanese, Steven J Staffa, Mitali Bose, Matthew Toczylowlski, Katie P Fehnel","doi":"10.1097/WNP.0000000000001153","DOIUrl":"https://doi.org/10.1097/WNP.0000000000001153","url":null,"abstract":"<p><strong>Purpose: </strong>Maximal safe resection is recommended for intramedullary spinal cord tumors (IMSCT). Tools to minimize surgical morbidity are, therefore, critical. We review intraoperative neurophysiologic monitoring (IONM) in a large series of pediatric IMSCTs, focusing on its relationship with functional outcomes and surgical decision making.</p><p><strong>Methods: </strong>A single-institution, retrospective review of all IMSCT resections with IONM from 2000 to 2022 was conducted. Univariate analysis evaluated IONM changes with clinical and functional outcomes across an extended follow-up period.</p><p><strong>Results: </strong>Among the 59 IMSCT cases with IONM that met inclusion, somatosensory evoked potentials were used in 89.8%, motor evoked potentials in 86.4%, and Direct wave monitoring in 18.6%. Almost a third of patients experienced intraoperative changes in motor evoked potentials, somatosensory evoked potentials, and Direct waves, respectively, depending on the modality of IONM used. Monitoring alerts were more common in older patients (≥15 years) and those with larger tumors, and often led to longer hospital/intensive care unit stays and a higher rate of discharge to inpatient rehabilitation. Motor evoked potential and Direct wave alerts significantly affected the surgeon's decision to stop further resection (p = 0.001 and p = 0.067). Marked somatosensory evoked potential changes were associated with worse immediate postoperative sensory deficits (<6-weeks, p < 0.05). At 1-year follow-up, most patients experienced improved functional outcomes, with favorable motor and sensory recovery.</p><p><strong>Conclusions: </strong>Multiple IONM modalities are technically feasible in pediatric IMSCTs and help guide surgical decision making. Intraoperative neurophysiologic monitoring alerts were more common in patients with larger tumors and older ages, significantly affecting the surgeon's decision to stop further resection. Although associated with longer hospital/intensive care unit stays and increased discharge rates to rehabilitation, IONM changes did not significantly affect long-term functional outcomes.</p>","PeriodicalId":15516,"journal":{"name":"Journal of Clinical Neurophysiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143501471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Expanding the Electroclinical Profile of CAPE.","authors":"Douglas R Nordli, Joshua Chang, Hiba A Haider","doi":"10.1097/WNP.0000000000001152","DOIUrl":"https://doi.org/10.1097/WNP.0000000000001152","url":null,"abstract":"<p><strong>Summary: </strong>This case report presents two illustrative cases of cyclic alternating pattern of encephalopathy, showcasing its distinct quantitative EEG signature alongside observed correlations with cardiorespiratory fluctuations. Recognizing cyclic alternating pattern encephalopathy patterns may provide clinicians with an actionable marker, guiding timely interventions and potentially improving outcomes in critically ill patients.</p>","PeriodicalId":15516,"journal":{"name":"Journal of Clinical Neurophysiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143515837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Subclinical Epileptiform Discharge in Patients With Alzheimer Dementia: A Systematic Review and Meta-Analysis.","authors":"Wei-Chih Yeh, Yuan-Han Yang, Ying-Sheng Li, Chung-Yao Hsu","doi":"10.1097/WNP.0000000000001148","DOIUrl":"https://doi.org/10.1097/WNP.0000000000001148","url":null,"abstract":"<p><strong>Purpose: </strong>Patients with Alzheimer's dementia (AD) who do not have a history of epilepsy have a higher frequency of subclinical epileptiform discharge (SED) than healthy individuals. This meta-analysis aims to investigate the frequency of SED in patients with AD using different EEG protocols and to compare SED rates between early- and late-onset AD.</p><p><strong>Methods: </strong>This study adhered to the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. We searched various databases until January 2024 for studies reporting the frequency of SED in patients with AD who did not have a history of epilepsy. A meta-analysis was conducted using a random-effects model.</p><p><strong>Results: </strong>Thirteen studies involving 1,373 patients with AD were analyzed. The patients had a mean age of 71.2 years, and 59.3% were women. The pooled SED rate was found to be 18.3%. The SED rate was higher with extended EEG protocols (26.7%) than with routine EEG protocols (12.1%). It was also observed that patients with early-onset AD had higher SED rates with routine EEG protocols (14.4%) and extended EEG protocols (43.9%) than those with late-onset AD (10.5 and 21.3%, respectively). Furthermore, patients with AD had a 3.55 relative risk (P < 0.001) of SED compared with healthy controls. Specifically, patients with early-onset AD showed a significantly higher risk of developing SED than those with late-onset AD (relative risk, 4.48; P < 0.001).</p><p><strong>Conclusions: </strong>Subclinical epileptiform discharge frequency was high in patients with AD, particularly in those with early onset AD.</p>","PeriodicalId":15516,"journal":{"name":"Journal of Clinical Neurophysiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143441105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Epilepsy Surgery Education: A Survey of US Epilepsy Fellowship Program Directors.","authors":"Roohi Katyal, Irfan S Sheikh, Camilo Gutierrez, Saurabh R Sinha, B Keith Day, Jay R Gavvala, Sameer A Sheth, Elaine Wirrell, Sándor Beniczky, Fábio A Nascimento","doi":"10.1097/WNP.0000000000001144","DOIUrl":"https://doi.org/10.1097/WNP.0000000000001144","url":null,"abstract":"<p><strong>Purpose: </strong>To understand the current state of epilepsy surgery education delivered to epilepsy fellows in the United States.</p><p><strong>Methods: </strong>An online survey focused on characteristics of epilepsy surgery education was distributed to all 93 epilepsy fellowship program directors listed on the ACGME website (accessed in May 2022). Programs were stratified per the number of fellows currently enrolled: 0 to 3 (group A) and ≥4 (group B).</p><p><strong>Results: </strong>Forty-one of 93 (44%) epilepsy fellowship programs were included in the study. The average number of resective surgeries, ablations, or corpus callosotomies per year was mostly 0 to 30 (54%) in group A and mostly >30 (80%) in group B (P = 0.05). The average number of intracranial implantations per year was mostly 0 to 20 (58%) in group A and mostly >20 (80%) in group B (P < 0.05). The average number of neurostimulation implantations per year was 15 (range 0-90; vagal nerve stimulation), 7 (range 0-25; responsive neurostimulation), and 4 (range 0-10; deep brain stimulation). In 78% of programs, fellows are not required to present a minimum number of epilepsy surgery cases in multidisciplinary conference before graduation. Roughly half of programs (51%) reported not using objective measures to assess fellow competency in epilepsy surgery.</p><p><strong>Conclusions: </strong>Our results suggest significant variability in epilepsy surgery volume and, consequently, fellow exposure to surgical cases and lack of standardized, objective measures in fellow teaching and assessment in the field of epilepsy surgery across programs in the United States. We advocate development of a core epilepsy surgery curriculum including minimum standards at the national level.</p>","PeriodicalId":15516,"journal":{"name":"Journal of Clinical Neurophysiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143399428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reference Values of the Tube-Based Laryngeal Adductor Reflex of the Healthy Recurrent Laryngeal Nerve.","authors":"Maria J Téllez, Juan Manuel Escobar-Montalvo, Catherine F Sinclair, Paola M Rodriguez Morel, Patricia Torralba, Sedat Ulkatan, Mark L Urken","doi":"10.1097/WNP.0000000000001150","DOIUrl":"https://doi.org/10.1097/WNP.0000000000001150","url":null,"abstract":"<p><strong>Purpose: </strong>This study aimed to establish reference values for laryngeal adductor reflex latency and amplitude under general anesthesia using a noninvasive technique with commercially available electromyographic endotracheal tubes.</p><p><strong>Methods: </strong>This retrospective observational study included 380 patients undergoing head and neck surgery. The inclusion criteria were recording the laryngeal adductor reflex from the nonsurgical side and the absence of pathology in the recurrent laryngeal nerve. Measurements were taken before incision and surgical completion.</p><p><strong>Results: </strong>The R1 component medians for the latency and amplitude were 20 ms and 448 µV for the right and 22 ms and 425 µV for the left LARs, respectively. There were significant differences in the R1 latencies between the sides. Quantile regression models revealed that 95th percentile amplitudes exceeded 400 µV, whereas 5% of our data set surpassed 600 µV. The R2 component was present in 26% of patients initially but decreased to 8% at surgical conclusion. The percentage difference between the median R1 value at the end of the surgery, compared with the opening value, was up to 4% for latency and 10% for amplitude.</p><p><strong>Conclusions: </strong>The R1 component of the laryngeal adductor reflex remains a reliable tool for intraoperative neuromonitoring. This is the largest study to provide reference values for laryngeal adductor reflex, aiding future diagnostic applications in head and neck surgeries.</p>","PeriodicalId":15516,"journal":{"name":"Journal of Clinical Neurophysiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143382589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accuracy of SEEG Source Localization: A Pilot Study Using Corticocortical Evoked Potentials.","authors":"Benjamin C Cox, Rachel J Smith, Ismail Mohamed, Jenna V Donohue, Mahtab Rostamihosseinkhani, Jerzy P Szaflarski, Rebekah J Chatfield","doi":"10.1097/WNP.0000000000001140","DOIUrl":"10.1097/WNP.0000000000001140","url":null,"abstract":"<p><strong>Introduction: </strong>EEG source localization is an established technique for localizing scalp EEG in medically refractory epilepsy but has not been adequately studied with intracranial EEG (iEEG). Differences in sensor location and spatial sampling may affect the accuracy of EEG source localization with iEEG. Corticocortical evoked potentials can be used to evaluate EEG source localization algorithms for iEEG given the known source location.</p><p><strong>Methods: </strong>We recorded 205 sets of corticocortical evoked potentials using low-frequency single-pulse electrical stimulation in four patients with iEEG. Averaged corticocortical evoked potentials were analyzed using 11 distributed source algorithms and compared using the Wilcoxon signed-rank test ( P < 0.05). We measured the localization error from stimulated electrodes and the spatial dispersion of each solution.</p><p><strong>Results: </strong>Minimum norm, standard low-resolution electromagnetic tomography (sLORETA), LP Norm, sLORETA-weighted accurate minimum norm (SWARM), exact LORETA (eLORETA), standardized weighted LORETA (swLORETA), and standardized shrinking LORETA-FOCUSS (ssLOFO) had the least localization error (13.3-15.7 mm) and were superior to focal underdetermined system solver (FOCUSS), logistic autoregressive average (LAURA, and LORETA, 17.9-21.7, P < 0.001). The FOCUSS solution had the smallest spatial dispersion (7.4 mm), followed by minimum norm, L1 norm, LP norm, and SWARM (20.8-28.3 mm). Gray matter stimulations had less localization error than white matter (median differences 3.1-6.1 mm) across all algorithms except SWARM, LORETA, and logistic autoregressive average. A multivariate linear regression showed that distance from the source to sensors and gray/white matter stimulation had a significant effect on localization error for some algorithms but not SWARM, minimum norm, focal underdetermined system solver, logistic autoregressive average, and LORETA.</p><p><strong>Conclusions: </strong>Our study demonstrated that minimum norm, L1 norm, LP norm, and SWARM localize iEEG corticocortical evoked potentials well with lower localization error and spatial dispersion. Larger studies are needed to confirm these findings.</p>","PeriodicalId":15516,"journal":{"name":"Journal of Clinical Neurophysiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143122825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stimulation-Induced Seizures in Children Undergoing Stereo-EEG Evaluation.","authors":"Ranjith Kumar Manokaran, Ayako Ochi, Shelly Weiss, Ivanna Yau, Rohit Sharma, Hiroshi Otsubo, George M Ibrahim, Elizabeth J Donner, Puneet Jain","doi":"10.1097/WNP.0000000000001077","DOIUrl":"10.1097/WNP.0000000000001077","url":null,"abstract":"<p><strong>Purpose: </strong>This study reports our center's initial experience with the use of low-frequency stimulation in provoking stimulation-induced seizures (SIS) in children with drug-resistant epilepsy undergoing stereo-EEG evaluations.</p><p><strong>Methods: </strong>This retrospective study enrolled children aged 2 to 18 years with drug-resistant focal epilepsy who underwent stereo-EEG evaluation and extraoperative direct electrical cortical stimulation to elicit seizures. The low-frequency stimulation parameters consisted of biphasic square waveforms at frequency of 1 Hz, pulse width 1 millisecond, current 1 to 3 mA, and train duration of 20 seconds. Various epilepsy-related, imaging, neurophysiology, and surgery-related variables were collected and summarized.</p><p><strong>Results: </strong>Fourteen children (mean age 13 years; 57.1% girls) were included, 10 of whom had unilateral stereo-EEG coverage. Cortical stimulation for provoking seizures was performed after a median of 5 days after electrode implantation. The median number of electrode-contacts stimulated per patient was 42. Four patients (28.6%) experienced habitual SIS (all extratemporal). The etiology in three patients was focal cortical dysplasia. Interictal high-frequency oscillations at electrode-contacts provoking SIS were observed in three cases (75%). Two of these individuals (50%) had class 1 International League Against Epilepsy seizure outcome at last follow-up, after the resection of the brain regions generating SIS.</p><p><strong>Conclusions: </strong>Low-frequency (1-Hz) stimulation could provoke habitual SIS in nearly one-fourth of children with focal epilepsy undergoing stereo-EEG monitoring. This study provides a limited pediatric experience with the low-frequency cortical stimulation and SIS.</p>","PeriodicalId":15516,"journal":{"name":"Journal of Clinical Neurophysiology","volume":" ","pages":"126-131"},"PeriodicalIF":2.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139912745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Contraction-Induced H Reflexes of the Upper and Lower Limbs in Healthy Adults.","authors":"Antony Winkel, Mark Cook, Leslie Roberts","doi":"10.1097/WNP.0000000000001070","DOIUrl":"10.1097/WNP.0000000000001070","url":null,"abstract":"<p><strong>Purpose: </strong>Contraction-induced H reflexes are a late neurophysiologic response elicited with submaximal nerve stimulation during isometric muscle contraction. Mediated by spinal pathways, like other H reflexes, their use has remained somewhat limited despite a long history of development dating back to the original description by Hoffman. There is a paucity of data on normal reference ranges, which this article aims to add to.</p><p><strong>Methods: </strong>Contraction-induced H reflexes were elicited from the first dorsal interosseous, flexor carpi radialis, and tibialis anterior bilaterally in 100 healthy volunteers. Reference values, including side-to-side variation, were calculated. Pearson test and multiple regression were used to evaluate the relationship of H-reflex latency to height, age, and sex of participants.</p><p><strong>Results: </strong>The mean onset latencies of 28.00, 17.44, and 31.10 ms were seen for first dorsal interosseous, flexor carpi radialis, and tibialis anterior muscles, respectively. The calculated allowable side-to-side latency difference in individual participants was 3 to 4 ms. A correlation to participant height was seen.</p><p><strong>Conclusions: </strong>This work provides normal reference values of contraction-induced H reflexes to three muscles, including allowable side-to-side variation. The latter suggests that bilateral testing evaluating for asymmetry within an individual is likely to be optimally sensitive. The relationship to height is also confirmed.</p>","PeriodicalId":15516,"journal":{"name":"Journal of Clinical Neurophysiology","volume":" ","pages":"107-110"},"PeriodicalIF":2.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141446284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}