Respiration-related laryngeal electromyography in children with bilateral vocal fold paralysis.

We present 2 case reports to demonstrate the relationship between laryngeal muscle activity and respiration in children with bilateral vocal fold paralysis (BVFP) by simultaneous laryngeal electromyography (EMG) with recording of chest wall movement and intercostal muscle EMG. Laryngeal EMG was performed together with recording of chest wall movement in a 55-day-old girl who was undergoing tracheostomy for idiopathic congenital BVFP. Normal phasic activity was observed, i.e., the thyroarytenoid (TA) muscle was active during expiration and the posterior cricoarytenoid (PCA) muscle during inspiration, suggesting a good prognosis for recovery. The child was decannulated at 11 months. Laryngeal EMG together with recording of chest wall movement and intercostal EMG in a 5-year-old girl who was tracheostomy-dependent following tracheoesophageal fistula repair due to BVFP showed phasic activity during expiration for both the TA and PCA muscles, indicating aberrant regeneration of the PCA motor nerve. The timing of laryngeal muscle activity with respiration in the assessment of pediatric congenital BVFP is essential to demonstrate the presence of normal or abnormal medullary respiratory neuronal input to laryngeal motoneurons. In cases in which BVFP is due to recurrent laryngeal nerve injury, respiration-related laryngeal EMG will identify aberrant regeneration. Laryngeal EMG should be combined with intercostal muscle EMG in the evaluation of children with significant vocal fold dyfunction of either central or peripheral origin.