抄録
The purpose of this study was to evaluate the efficacy and safety of functional electrical stimulation in restoring glottal opening, ventilation, and exercise tolerance in case of bilateral laryngeal paralysis. A new generation stimulator, Genesis XP, and deep brain stimulation electrodes were surgically implanted into both posterior cricoarytenoid (PCA) muscles of canine, and the recurrent laryngeal nerves sectioned and repaired bilaterally. Vocal fold movement was measured endoscopically in the anesthetized animal during bimonthly sessions for over a year. The movement resulted from electrical stimulation of the PCA or from hypercapnia during spontaneous breathing. Exercise tolerance was measured on a treadmill using pulse oximetry and swallowing function was examined via videofluoroscopy. During the three months after surgery, there was minimal ventilatory compromise and near normal exercise tolerance in the stimulation-off state. PCA stimulation produced only nominal abduction. Beyond three months postoperatively, there was passive airway narrowing and further closure of the glottis during hypercapnia. The canine presented severe stridor and could walk for only 1 to 2 minutes on a treadmill. With the stimulation-on condition, the glottal area increased considerably, equaling that of a normally innervated animal. Exercise tolerance also returned to normal. There was no evidence of aspiration during deglutition. In conclusion, bilateral PCA stimulation offers a physiologic approach to rehabilitate ventilation to a normal level in the case of bilateral laryngeal paralysis.
