Bipolar Hooked-Wire Electromyographic Technique in the Evaluation of Pediatric Vocal Cord Paralysis

Abstract

Laryngeal electromyography is a valuable test to assess vocal cord paralysis in adults. This technique can be applied and adapted to the pediatric patient. In the operating room under general anesthesia and endoscopic guidance, bipolar hooked-wire electrodes are passed percutaneously through the anterior neck skin into both thyroarytenoid muscles. Electromyographic signals are evaluated during light anesthesia and on awakening. A critical appraisal of this technique is presented, including an analysis of sources of electrical interference in the operating room.

The clinical value of laryngeal electromyography in laryngeal immobility

“…Many LEMG studies do not refer to the duration of the potentials in the interpretation of the examinations. [11][12][13]27,32,30,36 It is common, when making a diagnosis of paralysis, for only polyphasic potentials and recruitment to be considered. 31 Our results suggest that MUAP duration should be measured whenever possible, as an increase in duration can be considered a criterion for the diagnosis of denervation, as is the case for facial nerve paralysis.…”

Electromyography in Children's Laryngeal Mobility Disorders

“…Indeed, there are many differences regarding technique and conditions among the subsequent studies ( Table 6). For example, while most used monopolar electrodes, only 2 used the bipolar variety 8,9 ; aside from the studies by Berkowitz 7 and Jacobs and Finkel, 8 the remaining works sampled either thyroarytenoid or posterior cricoarytenoid muscle only, leaving out the posterior cricoarytenoid more commonly.…”

Intraoperative laryngeal electromyography in children with vocal fold immobility: A simplified technique

“…While adolescents and select older children are able to comply with standard, office-based L-EMG assessment, infants and younger children will not participate with awake, volitional, task-focused examination. Techniques for performing L-EMG in children under anesthesia have been described, however the procedure requires the use of electromyography equipment in the operating room, which often must be further modified [10,[15][16][17][18]. Additionally, the presence of an electromyography-trained neurologist in the operating room for interpretation is advised, so that both the acoustic profile and electrical activity can be analysed effectively.…”

“…The presence or absence of SLN function helps localize the site of the lesion, as evaluation of the cricothyroid muscle allows for a more complete examination of the neuromuscular axis. While at least five papers have been published describing techniques for intraoperative L-EMG in children, none of these studies evaluated the cricothyroid muscles [10,[15][16][17][18]. This is likely explained by the fact that the function of this muscle cannot be fully assessed during spontaneous respiration under a light plane of general anesthesia.…”

“…Nevertheless, multiple studies examining the role of L-EMG in determining prognosis for recovery of VF paralysis in both adults and children have shown that the majority of prognostic information obtained by L-EMG is acquired through examination of the TA muscles; in fact many of these studies limited their assessment to L-EMG evaluation of the TA muscles alone [11,13,16,18].…”