Physiologic effect of electrical stimulation on reinnervation of the canine larynx

• Published in: Otolaryngology-head and neck surgery 2004-08, Vol.131 (2), p.P205-P205
• Main Authors: Harley, David, Jeremy, Dan Vos, Rodriguez, Ricardo, Katada, Akihird, Swelstad, Brad, Kusuma, Shashidhar, Zealear, David L
• Format: Article
• Language: English
• ISSN: 0194-5998; 1097-6817
• DOI: 10.1016/j.otohns.2004.06.386

Problem: Paralysis of the recurrent laryngeal nerve (RLN) leads to significant functional morbidity in affected patients. Methods: Six canines underwent RLN sectioning and reanastomosis. In the experimental group, the posterior cricoarytenoid (PCA) muscle was stimulated using an implantable electrical stimulator. Reinnervation through the RLN was documented through electromyography of the the thyroarytenoid (TA) and PCA muscles during physiologic trials. Results: At 110 days of interrupted stimulation, there was a trend toward enhanced native reinnervation and reduced foreign reinnervation. By 140 days of stimulation, this reduction became more significant and even approximated the normal contralateral side. Later, a period of continuous stimulation appeared to inhibit further innervation, both native and foreign, while the control group demonstrated a continued increase in overall innervation. Additionally, all reinnervation of the PCA, both foreign and native, was shown to occur exclusively through the reanastomosed RLN. Conclusion: Electrical stimulation of the dennervated larynx appears to inhibit the formation of foreign and erroneous reinnervation after injury to the RLN. When presented intermittently, in a more physiologic fashion, it appears to stimulate proper native reinnervation. Significance: While laryngeal paralysis poses a difficult problem to correct, electrical stimulation of the paralyzed musculature offers a promising option for future study. By showing that this model produces consistently hopeful results in the canine model, the opportunity exists for significant benefits for patients in the years to come. Support: None reported.