The role of laryngeal electromyography in the diagnosis of vocal fold immobility in children

Laryngeal electromyography, a useful tool in difficult cases of pediatric laryngeal mobility disorders

INTRODUCTION

Pediatric laryngeal mobility disorders constitute a challenge in terms of diagnosis and treatment, especially in small children and those complex patients with prior history of prolonged intubation or surgery. Laryngeal electromyography (L-EMG) may help to distinguish vocal fold paralysis from fixation.

MATERIAL AND METHODS

Ten children with laryngeal mobility disorders (including bilateral vocal fold immobility (BVFI) or unilateral vocal fold immobility (UVFI) with contralateral hypomobility) underwent suspension laryngoscopy and L-EMG between July 2019 and March 2021. The EMG data were acquired simultaneously in both thyroarytenoid muscles. Anesthesia was lightened until volitional activity appeared like cough, cry or spontaneous Valsalva maneuver.

RESULTS

We found secondary airway lesions in 2 patients and 3 vocal fold fixation. L-EMG recordings were pathologic in 4 patients (3 moderate and 1 severe nerve lesion). No recurrent laryngeal nerve injury was found in congenital BVFI cases. The data from both suspension laryngoscopy and L-EMG recordings influenced clinical decision-making.

CONCLUSIONS

L-EMG adds value to suspension laryngoscopy in the management of pediatric patients with laryngeal mobility disorders. Selected cases such as patients with iatrogenic BVFI, UVFI with associated contralateral hypomobility or patients with combined pathologies may obtain the greatest benefit.

The impact of identifying laryngeal obstruction syndromes on reducing treatment of pediatric asthma: A systematic review

Inducible laryngeal obstruction (ILO) in children is underrecognized. This systematic review characterizes the scientific evidence on the impact of pediatric ILO diagnosis and treatment on asthma medication use. This review, registered with PROSPERO (CRD42020209168), utilized database searches in MEDLINE, EMBASE, CINAHL, and Web of Science from inception to October 2020. Both experimental and observational studies on ILO and asthma outcomes in patients ≤18 years were included. Population characteristics (sample size, sex, age, and comorbidities) and study outcomes (medication usage and respiratory symptoms) were extracted. The risk of bias was assessed with the National Toxicology Program's Office of Health Assessment and Risk of Bias Rating Tool. Data are presented narratively due to study heterogeneity. Of 1091 studies, 1076 titles and abstracts were screened after duplicate removal. Screening 31 full texts yielded eight pre-post studies. Patients were an average of 14.1 years old, 15% male, and >90% used asthma medication; 40% reported allergies, 30% gastroesophageal reflux, and 20% anxiety or depression. Most patients received at least one intervention, with 75% showing symptomatic improvement and >75% decreasing or stopping asthma medications. Studies were small with a high risk of selection, confounding, and detection bias. Asthma management was not a primary outcome in any of the studies. Overall, ILO patients were often diagnosed with or treated for asthma before ILO diagnosis. Evidence from individual studies suggests that comorbidities including ILO, gastroesophageal reflux, allergies, and anxiety should be considered in pediatric patients with asthma not responsive to medical therapy. Further research is required to determine the proportion of impacted asthma patients.

Pediatric Vocal Fold Paresis and Paralysis: A Narrative Review

Importance

Vocal fold paralysis (VFP) results from the disruption of neural motor outputs to laryngeal muscles. Children with VFP manifest various degrees of difficulties in phonation, breathing, and swallowing. Although the etiologic characteristics and symptoms of VFP are well established in adults, corresponding clinical profiles are notably different in children. Clinical management of VFP is particularly challenging in children because their larynges are still actively developing and the recovery of disrupted laryngeal nerves is often unpredictable. This review discusses the neurologic conditions and diagnostic and treatment considerations in pediatric VFP.

Observations

Injury to the peripheral laryngeal nerves and certain central nervous system diseases, such as Arnold-Chiari malformation type II, can result in VFP in infants and children. The incidence of unilateral vs bilateral VFP is variable across pediatric studies. Most reported VFP cases are associated with injury of the recurrent laryngeal nerve. Laryngeal electromyography requires needle insertion that must be performed under anesthesia with special care in the pediatric setting. Neither normative values nor standardized procedures of laryngeal electromyography are currently established for the pediatric population. Laryngeal reinnervation, endoscopic arytenoid abduction lateropexy, and laryngeal pacing are plausible treatment options for pediatric VFP. Despite these new advances in the field, no corresponding efficacy data are available for clinicians to discern which type of patients would be the best candidates for these procedures.

Conclusions and Relevance

The neuroanatomy and neurophysiology of VFP remain more elusive for the pediatric population than for adults. Basic and clinical research is warranted to fully comprehend the complexity of this laryngeal movement disorder and to better inform and standardize clinical practice.

Experience with laryngeal reinnervation using nerve-muscle pedicle in pediatric patients

OBJECTIVE

Vocal fold paralysis (VFP) in adducted position remains a challenge for airway surgeons. Alternatives to tracheostomies such as lateralization, cordectomy, and posterior rib grafting disrupt the laryngeal tissue or framework and carry an increased risk of aspiration. Laryngeal reinnervation using nerve-muscle pedicle (NMP), carries the distinct advantage of preserving the larynx, sparing the recurrent laryngeal nerve, and obtaining an active VF abduction. The aim of this study was to evaluate the success and complications of laryngeal reinnervation using nerve-muscle pedicle (NMP) in pediatric patients presenting with dyspnea related to VFP in adducted position.

METHODS

In this case series performed at a tertiary care referral center, review of medical records on all pediatric patients with VFP in adduction treated with laryngeal reinnervation using NMP between 1999 and 2017. Data were collected on the preoperative flexible laryngoscopy, suspension micro-laryngoscopy, and laryngeal electromyography as well as post-operative clinical assessment of the voice and airway. All patients underwent surgery consisting of the transfer of an innervated omohyoid muscle pedicle onto the paralyzed posterior cricoarytenoid muscle. The main outcomes measured were the clinical and fiberoptic laryngoscopic airway assessment monthly for the first 6 months, then at 12 months and annually thereafter. Clinical assessment included dyspnea evaluation based on a visual analog scale and voice assessment using the GRBAS scores. Complications from the treatment were also noted. These outcomes were determined before collection of data.

RESULTS

16 cases were identified, with a mean age of 4 years. The recurrent laryngeal nerve paralysis was bilateral in 3 cases and unilateral in 13 cases. There were no peri or postoperative complications. After a mean follow-up of 7 years, vocal fold abduction was observed in 10 out of 16 cases and disappearance of paradoxical inspiratory adduction in 3 cases. Persistent dyspnea was noted in 7 cases (44%), and moderate dysphonia was present in 11 cases (69%). Finally, additional procedures were necessary in 2 patients (13%) to achieve the outcomes.

CONCLUSIONS

Laryngeal reinnervation using NMP may be used in pediatric patients. This procedure, is safe and allows us to spare the recurrent laryngeal nerve while obtaining an active VF abduction in the majority of cases, and an improvement in breathing in most cases.

QUALITY OF EVIDENCE

4.

Neonatal vocal fold motion impairment after complex aortic arch reconstruction: What should parents expect after diagnosis?

OBJECTIVES

To study the incidence, sequelae, follow up, and recovery rate of vocal fold motion impairment (VFMI) after complex aortic arch reconstruction in neonates.

STUDY DESIGN

Retrospective case control study.

METHODS

We retrospectively evaluated 105 neonates who underwent complex aortic arch reconstruction from 2014 to 2016. We compared patients that did have VFMI compared to a control group of patients with normal vocal fold movement. Descriptive statistics were computed for all demographic and clinical variables by treatment group.

RESULTS

36% of patients were evaluated for VFMI (n = 38) by an otolaryngologist. The incidence of VFMI was 22% (n = 23). Females were more likely to have VFMI (p = 0.02). Aspiration was more common in patients with VFMI (p = 0.006). The difference in age, weight, incidence of pneumonia, nasogastric tube, gastrostomy, total length of stay, genetic anomaly, and reintubation was not significant between the VFMI group and control group (p > 0.05). Tracheostomy was not performed in any patients with unilateral paralysis. Only 61% of patients followed up in clinic (n = 14). 64% of patients showed improvement or resolution (n = 9). Average time to improvement was 4.8 months. Average time to complete resolution was 10.5 months.

CONCLUSIONS

VFMI after complex aortic arch reconstruction is relatively common. Despite increased aspiration in patients with VFMI, pneumonia did not occur at all in either group. Tracheostomy was not necessary in any patients with a unilateral paralysis. Most patients showed an improvement in the VFMI within 5 months of surgery. Our data support the need for otolaryngology follow-up after the diagnosis of VFMI.

Pediatric laryngeal electromyography technique for vocal fold immobility using bipolar double hookwire electrodes

Vocal fold immobility (VFI) is a common cause of dysphonia and dysphagia in children. Laryngeal electromyography (LEMG) is an important adjunctive test in its diagnosis and treatment. In this study, we present an alternative technique in which bipolar double hookwire electrodes allow simultaneous placement and recordings from the bilateral thyroarytenoid and posterior cricoarytenoid muscles. Details of the technique are shown for a 5 y/o F with history of Neurofibromatosis Type 2 with left VFI and aspiration and dysphonia. This modified technique for pediatric LEMG has the potential to be a useful tool in predicting return of laryngeal function.

Consensus statement: Using laryngeal electromyography for the diagnosis and treatment of vocal cord paralysis

INTRODUCTION

The purpose of this study was to develop an evidence-based consensus statement regarding use of laryngeal electromyography (LEMG) for diagnosis and treatment of vocal fold paralysis after recurrent laryngeal neuropathy (RLN).

METHODS

Two questions regarding LEMG were analyzed: (1) Does LEMG predict recovery in patients with acute unilateral or bilateral vocal fold paralysis? (2) Do LEMG findings change clinical management in these individuals? A systematic review was performed using American Academy of Neurology criteria for rating of diagnostic accuracy.

RESULTS

Active voluntary motor unit potential recruitment and presence of polyphasic motor unit potentials within the first 6 months after lesion onset predicted recovery. Positive sharp waves and/or fibrillation potentials did not predict outcome. The presence of electrical synkinesis may decrease the likelihood of recovery, based on 1 published study. LEMG altered clinical management by changing the initial diagnosis from RLN in 48% of cases. Cricoarytenoid fixation and superior laryngeal neuropathy were the most common other diagnoses observed.

CONCLUSIONS

If prognostic information is required in a patient with vocal fold paralysis that is more than 4 weeks and less than 6 months in duration, then LEMG should be performed. LEMG may be performed to clarify treatment decisions for vocal fold immobility that is presumed to be caused by RLN. Muscle Nerve 53: 850-855, 2016.

Case Report: Neonate With Stridor and Subcutaneous Emphysema as the Only Signs of Physical Abuse

A stridulous, dysphonic cry with no external signs of trauma is a unique and unusual presenting sign for physical abuse. We report a previously healthy neonate with unremarkable birth history and medical history who presented with stridor and hypopharyngeal perforation due to physical abuse. This case highlights the need for further evaluation for traumatic injuries in the setting of unexplained new-onset stridor and consideration of physical abuse in the differential diagnosis.

Velopharyngeal incompetence in patients with cleft palate, flexible video pharyngoscopy and perceptual speech assessment: a correlational pilot study

Objectives:

To assess the role of video endoscopy in evaluating velopharyngeal incompetence and investigate a possible relationship between velopharyngeal incompetence type and speech defect in cleft palate patients.

Methods:

A prospective study of 28 pre- or post-operative cleft palate patients with speech defects who attended Plastic Surgery–Cleft Palate and ENT out-patient clinics was performed. The velar defect type was determined using a flexible endoscope and findings were video recorded. Speech pathology was assessed using the cleft palate audit protocol for speech.

Results:

A significant, clinically relevant relationship was noted between the perceived characteristics of hypernasality and velopharyngeal insufficiency type. Hypernasal speech was a definite clinical indicator of velopharyngeal incompetence, and the type 1 velopharyngeal defect was most common. Type 1 velopharyngeal coronal-type dysfunction was strongly associated with hypernasality (p < 0.05). When speech substitution was noted, type 2 velopharyngeal (or sagittal) incompetence could be predicted (p < 0.05).

Conclusion:

In the management of cleft palate patients, it is important that surgical correction of the defect and achieving velopharyngeal competency for speech are performed simultaneously. Pre-operative velopharyngeal endoscopy with speech assessment will define the anatomical and functional bases for velopharyngeal correction and assist in planning and tailoring the pharyngeal flap.

Arytenoid dislocation: An analysis of the contemporary literature

OBJECTIVES/HYPOTHESIS

To discuss the incidence, diagnosis, laryngeal findings, and management of arytenoid dislocation as a separate entity from vocal fold paralysis.

STUDY DESIGN

Literature review.

METHODS

A contemporary review of the literature was performed by searching the terms arytenoid cartilage dislocation and subluxation in various combinations. Articles were analyzed and selected based on relevance and content.

RESULTS

Arytenoid dislocation is described as an uncommon laryngeal finding associated with intubation or blunt laryngeal trauma. The majority of recent publications are case reports or small case series. Diagnosis of arytenoid dislocation with flexible laryngoscopy, helical computed tomography, videostroboscopy, and laryngeal electromyography is recommended. In most reported cases, diagnosis has been made based on the position of the arytenoid at laryngoscopy. Reduction and repositioning of the arytenoid cartilage is reported with limited success noted with delayed diagnosis. Speech therapy may also be a beneficial treatment option.

CONCLUSIONS

Although arytenoid dislocation is reported in the literature, the body of available evidence fails to sufficiently differentiate it as a separate entity from unilateral vocal fold paralysis. Flexible laryngoscopy is inadequate as a standalone procedure to distinguish arytenoid dislocation from laryngeal nerve injury.

A novel physiological investigation of the functional residual capacity by the bias flow nitrogen washout technique in infants

The dynamic functional residual capacity (FRC(dyn)), the lung volume most routinely measured in infants, is an unreliable volume landmark. In addition to the FRC(dyn), we measured the (passive) static FRC (FRC(st)) by inducing a brief post-hyperventilation apnea (PHA) in 33 healthy infants aged 7.4-127.2 weeks. A commercial system for nitrogen (N2) washout to measure FRC, and a custom made system to monitor and record flow and airway opening pressure signals in real-time were used in unison. Infants were manually hyperventilated to induce a PHA. After the last passive expiration, FRC(st) was estimated by measuring the volume of N2 expired after end-passive expiratory switching of the inspired gas from room air to 100% oxygen during the post-expiratory apneic pause. Repeatable intrasubject FRC(st) and FRC(dyn) measurements overlapped in most infants including the younger ones (P = 0.2839). Mean (95% confidence interval [CI]) FRC(st) was 21.1 (20.0-22.3), and error-corrected FRC(dyn) was 21.4 (20.4-22.4) ml/kg. Mean (washout time [t]) tFRC(st) was longer than tFRC(dyn) 60 sec (95% CI 55-65) versus 47 sec (95% CI 43-51) (P < 0.0001). The FRC and washout time were dependent on body length, weight and age. We conclude that the FRC(st) is not different from the FRC(dyn) in infants. The FRC(st) is a reliable volume landmark because the PHA stabilizes the end-expiratory level by potentially abolishing the sedated infant's breathing strategies. The FRC(st) lacks potential sources of errors and disadvantages associated with measuring the FRC(dyn). The findings cast significant doubt on the traditional physiology of air trapping in healthy infants' lungs.