[Selective laryngeal re-innervations in the dog by nervous microsutures of branches of the recurrent laryngeal nerve].

Introduction: This work has been carried out to investigate in an animal model, the possibility of surgical selective reinnervation of the larynx following destruction of the laryngeal branch of the vagus nerve.

Material And Methods: In ten dogs, on the right side of the neck only, the recurrent laryngeal nerve was identified, cut and section of the nerve removed. Following this the hemi-larynx on the operated side was reinnervated in the following manner. Using a microsurgical suture (described in the text) the motor nerves from extra-laryngeal muscles were anastomosed onto the nerves supplying the intrinsic abductors and adductors of the larynx. The nerve to sterno-thyroid was anastomosed onto the nerve supplying the posterior crico-arytenoid muscle (vocal cord abductor). Similarly the nerve supplying thyrohyoid was anastomosed onto the cut distal end of the adductor division of the recurrent laryngeal nerve. Clinical, electromyographical and histological evaluations have been used to prove the reinnervation.

Results: In the nine surviving animals successful re-innervations, as defined by the return of normal function, has been achieved for posterior crico-arytenoid and 7 adductor muscles.

Conclusion: This study has demonstrated the feasibility of laryngeal reinnervation after surgical section of the recurrent laryngeal nerve, and give some cause for optimism for its ultimate application in man.