Analysis of wave III of brain stem auditory evoked potential waveforms during microvascular decompression of cranial nerve VII for hemifacial spasm

INTRODUCTION:: Intraoperative monitoring of brain stem auditory evoked potential during microvascular decompression (MVD) prevent hearing loss (HL). Previous studies have shown that changes in wave III (wIII) are an early and sensitive sign of auditory nerve injury. OBJECTIVE:: To evaluate the changes of amplitude and latency of wIII of brain stem auditory evoked potential during MVD and its association with postoperative HL. Hearing loss was classified by American Academy of Otolaryngology - Head and Neck Surgery (AAO-HNS) criteria, based on changes in pure tone audiometry and speech discrimination score. METHODS:: Retrospective analysis of wIII in patients who underwent intraoperative monitoring with brain stem auditory evoked potential during MVD was performed. A univariate logistic regression analysis was performed on independent variables amplitude of wIII and latency of wIII at change max and On-Skin, or a final recording at the time of skin closure. A further analysis for the same variables was performed adjusting for the loss of wave. RESULTS:: The latency of wIII was not found to be significantly different between groups I and II. The amplitude of wIII was significantly decreased in the group with HL. Regression analysis did not find any increased odds of HL with changes in the amplitude of wIII. CONCLUSIONS:: Changes in wave III did not increase the odds of HL in patients who underwent brain stem auditory evoked potential s during MVD. This information might be valuable to evaluate the value of wIII as an alarm criterion during MVD to prevent HL. © 2014 by the American Clinical Neurophysiology Society

Playfully Assessing Lower Extremity Selective Voluntary Motor Control in Children With Cerebral Palsy: Psychometric Study

Background Objective measures specifically assessing selective voluntary motor control are scarce. Therefore, we have developed an interval-scaled assessment based on accelerometers. Objective This study provided a preliminary evaluation of the validity and reliability of this novel gamelike assessment measuring lower limb selective voluntary motor control in children with cerebral palsy (CP). Methods Children with CP and their neurologically intact peers were recruited for this psychometric evaluation of the assessgame. The participants played the assessgame and steered an avatar by selective hip, knee, or ankle joint movements captured with accelerometers. The assessgame’s scores provide information about the accuracy of the selective movement of the target joint and the amplitude and frequency of involuntary movements occurring in uninvolved joints. We established discriminative validity by comparing the assessgame scores of the children with CP with those of the neurologically intact children, concurrent validity by correlations with clinical scores and therapists’ opinions, and relative and absolute test-retest reliability. Results We included 20 children with CP (mean age 12 years and 5 months, SD 3 years and 4 months; Gross Motor Function Classification System levels I to IV) and 31 neurologically intact children (mean age 11 years and 1 month, SD 3 years and 6 months). The assessgame could distinguish between the children with CP and neurologically intact children. The correlations between the assessgame’s involuntary movement score and the therapist’s rating of the occurrence of involuntary movements during the game were moderate (Spearman ρ=0.56; P=.01), whereas the correlations of the assessgame outcomes with the Selective Control Assessment of the Lower Extremity and Gross Motor Function Classification System were low and not significant (|ρ|≤0.39). The intraclass correlation coefficients were >0.85 and indicated good relative test-retest reliability. Minimal detectable changes amounted to 25% (accuracy) and 44% (involuntary movement score) of the mean total scores. The percentage of children able to improve by the minimal detectable change without reaching the maximum score was 100% (17/17) for the accuracy score and 94% (16/17) for the involuntary movement score. Conclusions The assessgame proved reliable and showed discriminative validity in this preliminary evaluation. Concurrent validity was moderate with the therapist’s opinion but relatively poor with the Selective Control Assessment of the Lower Extremity. We assume that the assessment’s gamelike character demanded various other motor control aspects that are less considered in current clinical assessments

Validity and reliability of an accelerometer-based assessgame to quantify upper limb selective voluntary motor control

From Springer Nature via Jisc Publications RouterIntroduction: Current clinical assessments measure selective voluntary motor control (SVMC) on an ordinal scale. We introduce a playful, interval-scaled method to assess SVMC in children with brain lesions and evaluate its validity and reliability. Methods: Thirty-one neurologically intact children (median [1st-3rd quartile]: 11.6 years [8.5–13.9]) and 33 patients (12.2 years [8.8–14.9]) affected by upper motor neuron lesions with mild to moderate impairments participated. Using accelerometers, they played a movement tracking game (assessgame) with isolated joint movements (shoulder, elbow, lower arm [pro−/supination], wrist, and fingers), yielding an accuracy score. Involuntary movements were recorded simultaneously and resulted in an involuntary movement score. Both scores were normalized to the performance of 33 neurologically intact adults (32.5 years [27.9; 38.3]), which represented physiological movement patterns. We correlated the assessgame outcomes with the Manual Ability Classification System, Selective Control of the Upper Extremity Scale, and a therapist rating of involuntary movements. Furthermore, a robust ANCOVA was performed with age as covariate, comparing patients to their healthy peers at the age levels of 7.5, 9, 10.5, 12, and 15 years. Intraclass correlation coefficients and smallest real differences indicated relative and absolute reliability. Results: Correlations (Kendall/Spearman) for the accuracy score were τ = 0.29 (p = 0.035; Manual Ability Classification System), ρ = − 0.37 (p = 0.035; Selective Control of the Upper Extremity Scale), and ρ = 0.64 (p < 0.001; therapist rating). Correlations for the involuntary movement metric were τ = 0.37 (p = 0.008), ρ = − 0.55 (p = 0.001), and ρ = 0.79 (p < 0.001), respectively. The robust ANCOVAs revealed that patients performed significantly poorer than their healthy peers in both outcomes and at all age levels except for the dominant/less affected arm, where the youngest age group did not differ significantly. Robust intraclass correlation coefficients and smallest real differences were 0.80 and 1.02 (46% of median patient score) for the accuracy and 0.92 and 2.55 (58%) for involuntary movements, respectively. Conclusion: While this novel assessgame is valid, the reliability might need to be improved. Further studies are needed to determine whether the assessgame is sensitive enough to detect changes in SVMC after a surgical or therapeutic intervention.pubpu

Diagnostic accuracy of motor evoked potentials to detect neurological deficit during idiopathic scoliosis correction:a systematic review

OBJECTIVE The goal of this study was to evaluate the efficacy of intraoperative transcranial motor evoked potential (TcMEP) monitoring in predicting an impending neurological deficit during corrective spinal surgery for patients with idiopathic scoliosis (IS). METHODS The authors searched the PubMed and Web of Science database for relevant lists of retrieved reports and/or experiments published from January 1950 through October 2014 for studies on TcMEP monitoring use during IS surgery. The primary analysis of this review fit the operating characteristic into a hierarchical summary receiver operating characteristic curve model to determine the efficacy of intraoperative TcMEP-predicted change. RESULTS Twelve studies, with a total of 2102 patients with IS were included. Analysis found an observed incidence of neurological deficits of 1.38% (29/2102) in the sample population. Of the patients who sustained a neurological deficit, 82.8% (24/29) also had irreversible TcMEP change, whereas 17.2% (5/29) did not. The pooled analysis using the bivariate model showed TcMEP change with sensitivity (mean 91% [95% CI 34%-100%]) and specificity (mean 96% [95% CI 92-98%]). The diagnostic odds ratio indicated that it is 250 times more likely to observe significant TcMEP changes in patients who experience a new-onset motor deficit immediately after IS correction surgery (95% CI 11-5767). TcMEP monitoring showed high discriminant ability with an area under the curve of 0.98. CONCLUSIONS A patient with a new neurological deficit resulting from IS surgery was 250 times more likely to have changes in TcMEPs than a patient without new deficit. The authors' findings from 2102 operations in patients with IS show that TcMEP monitoring is a highly sensitive and specific test for detecting new spinal cord injuries in patients undergoing corrective spinal surgery for IS. They could not assess the value of TcMEP monitoring as a therapeutic adjunct owing to the limited data available and their study design

First validation of a novel assessgame quantifying selective voluntary motor control in children with upper motor neuron lesions

Julia Balzer - ORCID 0000-0001-7139-229X https://orcid.org/0000-0001-7139-229XThe question whether novel rehabilitation interventions can exploit restorative rather than compensatory mechanisms has gained momentum in recent years. Assessments measuring selective voluntary motor control could answer this question. However, while current clinical assessments are ordinal-scaled, which could affect their sensitivity, lab-based assessments are costly and time-consuming. We propose a novel, interval-scaled, computer-based assessment game using low-cost accelerometers to evaluate selective voluntary motor control. Participants steer an avatar owl on a star-studded path by moving the targeted joint of the upper or lower extremities. We calculate a target joint accuracy metric, and an outcome score for the frequency and amplitude of involuntary movements of adjacent and contralateral joints as well as the trunk. We detail the methods and, as a first proof of concept, relate the results of select children with upper motor neuron lesions (n = 48) to reference groups of neurologically intact children (n = 62) and adults (n = 64). Linear mixed models indicated that the cumulative therapist score, rating the degree of selectivity, was a good predictor of the involuntary movements outcome score. This highlights the validity of this assessgame approach to quantify selective voluntary motor control and warrants a more thorough exploration to quantify changes induced by restorative interventions.This work was supported by the Swiss National Science Foundation (Grant numbers 32003B_156646 and 32003B_179471)https://doi.org/10.1038/s41598-019-56495-89pubpu

Brainstem Auditory Evoked Potentials' Diagnostic Accuracy for Hearing Loss: Systematic Review and Meta-Analysis

Background: Microvascular decompression (MVD) utilizes brainstem auditory evoked potential (BAEP) intraoperative monitoring to reduce the risk of iatrogenic hearing loss. Studies report varying efficacy and hearing loss rates during MVD with intraoperative monitoring. Objectives: This study aims to perform a comprehensive review and study of diagnostic accuracy of BAEPs during MVD to predict hearing loss in studies published from January 1984 to December 2013. Methods: The PubMed/MEDLINE and World Science databases were searched. Studies performed MVD for trigeminal neuralgia, hemifacial spasm, glossopharyngeal neuralgia or geniculate neuralgia and monitored intraoperative BAEPs to prevent hearing loss. Retrospectively, BAEP parameters were compared with postoperative hearing. The diagnostic accuracy of significant change in BAEPs, which includes loss of response, was tested using summary receiver operative curve and diagnostic odds ratio (DOR). Results: A total of 13 studies were included in the analysis with a total of 2,540 cases. Loss of response pooled sensitivity, specificity, and DOR with 95% confidence interval being 74% (60–84%), 98% (88–100%), and 69.3 (18.2–263%), respectively. The similar significant change results were 88% (77–94%), 63% (40–81%), and 9.1 (3.9–21.6%). Conclusion: Patients with hearing loss after MVD are more likely to have shown loss of BAEP responses intraoperatively. Loss of responses has high specificity in evaluating hearing loss. Patients undergoing MVD should have BAEP monitoring to prevent hearing loss

Validity and reliability of an electromyography-based upper limb assessment quantifying selective voluntary motor control in children with upper motor neuron lesions

From SAGE Publishing via Jisc Publications RouterCurrent clinical assessments evaluating selective voluntary motor control are measured on an ordinal scale. We combined the Selective Control of the Upper Extremity Scale (SCUES) with surface electromyography to develop a more objective and interval-scaled assessment of selective voluntary motor control. The resulting Similarity Index (SI) quantifies the similarity of muscle activation patterns. We aimed to evaluate the validity and reliability of this new assessment named SISCUES (Similarity Index of the SCUES) in children with upper motor neuron lesions. Thirty-three patients (12.2 years [8.8;14.9]) affected by upper motor neuron lesions with mild to moderate impairments and 31 typically developing children (11.6 years [8.5;13.9]) participated. We calculated reference muscle activation patterns for the SISCUES using data of 33 neurologically healthy adults (median [1st; 3rd quantile]: 32.5 [27.9; 38.3]). We calculated Spearman correlations (ρ) between the SISCUES and the SCUES and the Manual Ability Classification System (MACS) to establish concurrent validity. Discriminative validity was tested by comparing scores of patients and healthy peers with a robust ANCOVA. Intraclass correlation coefficients2,1 and minimal detectable changes indicated relative and absolute reliability. The SISCUES correlates strongly with SCUES (ρ = 0.76, p < 0.001) and moderately with the MACS (ρ = −0.58, p < 0.001). The average SISCUES can discriminate between patients and peers. The intraclass correlation coefficient2,1 was 0.90 and the minimal detectable change was 0.07 (8% of patients’ median score). Concurrent validity, discriminative validity, and reliability of the SISCUES were established. Further studies are needed to evaluate whether it is responsive enough to detect changes from therapeutic interventions.Funder: Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung; FundRef: https://doi.org/10.13039/501100001711; Grant(s): 32003B_179471Funder: Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung; FundRef: https://doi.org/10.13039/501100001711; Grant(s): 32003B_156646104pubpub

Validity and reliability of an electromyography-based similarity index to quantify lower extremity selective voluntary motor control in children with cerebral palsy

Julia Balzer - ORCID: 0000-0001-7139-229X https://orcid.org/0000-0001-7139-229XMarietta van der Linden - ORCID: 0000-0003-2256-6673 https://orcid.org/0000-0003-2256-6673Thomas Mercer - ORCID: 0000-0002-5078-4769 https://orcid.org/0000-0002-5078-4769Deposited VoR 2022-03-31OBJECTIVE To quantify selective voluntary motor control (SVMC) objectively and more precisely, we combined the “Selective Control Assessment of the Lower Extremity” (SCALE) with surface electromyography. The resulting Similarity Index (SI) measures the similarity of muscle activation patterns. This study evaluated the preliminary validity and reliability of this novel SISCALE measure in children with cerebral palsy (CP).METHOD We investigated concurrent validity by correlating the SISCALE of 24 children with CP (median age 10.6 years) with comparator assessments . For discriminative validity, the patients’ SISCALE scores were compared to 31 neurologically intact age-matched peers. Test-retest reliability was quantified using intraclass correlation coefficients (ICC) and minimal detectable change (MDC) values.RESULTS The SISCALE correlated strongly with the SCALE (ρ = 0.90, p<.001) and the Gross Motor Function Classification System (ρ = -0.74, p<.001). SISCALE scores were significantly lower in children with CP compared to healthy peers. Test-retest reliability appeared good (for the more and less affected leg, ICC ≥ 0.84, and MDC ≤ 0.17).CONCLUSION Validity and reliability of the SISCALE leg and total scores lay within clinically acceptable ranges. Further clinimetric analyses should include responsiveness.SIGNIFICANCE A neurophysiology-based assessment could contribute to a more refined assessment of SVMC impairments.7pubpu