Laryngeal Denervation Reinnervation Surgery for Adductor Spasmodic Dysphonia Surgical treatments for adductor Spasmodic Dysphonia (AdSD) have enjoyed a resurgence over the last ten years. Selective laryngeal adductor denervation and reinnervation (SLAD/R) surgery is a procedure whereby intrinsic endolaryngeal closing forces are reduced and the AdSD patient is left with a normal or near normal voice without vocal cord spasm. This procedure was designed as a surgical analogue to the commonly used botulinum toxin injections and similar muscles are treated. What is involved in the operation? Under general anesthesia, the patient's neck is explored and the laryngeal thyroid cartilage is opened through large windows, similar to those used in thyroplasty. The anterior branch of the recurrent laryngeal nerve is identified, and distal branches terminating in the thyroarytenoid (TA) and lateral cricoarytenoid (LCA) are verified using intraoperative evoked electromyography. The nerves to the TA and LCA are then severed and the proximal stump of the recurrent laryngeal nerve is sewn to the exterior portion of the inferior cornu of the thyroid cartilage. The distal stump of the TA nerve is then anastomosed to a previously harvested branch of the ansa cervicalis, usually a branch that terminated in the sternohyoid muscle. These last steps are performed under magnification. Fine 9-0 or 8-0 suture is used for the neurorrhaphy. Because the distal nerve to the LCA muscle is too small for precise anastomosis, the nerve and the LCA muscle are further transected and weakened by performing a partial myotomy. Following the microsurgical procedures, the thyroid cartilage windows are closed and the proximal stump of the anterior branch of the recurrent nerve is purposely kept outside the laryngeal cartilages to avoid any undesired reinnervation. The procedure is then performed on the contralateral side, so that bilateral closing muscles are treated. The approach is designed so that the posterior branch of the recurrent nerves that contain fibers destined for the vocal cord abductors (the posterior cricoarytenoid muscles) are spared. The skin flaps are closed over a drain and the patient is extubated in the operating room. What should the patient expect during recovery? The patient will have a weak breathy voice for several months following the surgery and mild to moderate dysphagia for several weeks. After reinnervation, the great majority of patients are left with a normal or near normal voice that is free of spasms. There has been no long-term dysphagia reported. A large percentage (~90%) of the patients are very satisfied with their post-operative voice. Some patients have lost some of their upper register vocal range. Expert listeners have noted some degree of breathiness in up to 30% of patients, with the majority of these rated as mild or moderate. In a long term study, 83% of patients would recommend this surgical procedure to someone in a similar situation as cited in long-term follow up study. Advantages and Benefits Denervation is bilateral Denervation is selective and specific for the laryngeal adductors PCA (abductor) innervation is preserved A surgical analogue to botulinum toxin inducted denervation Occupy laryngeal neuromuscular junctions with “good” nerve Prevent denervation atrophy Remove vocal strain quality of adductor Spasmodic Dysphonia Reduce the laryngeal resistance associated with AdSD Improve vocal fluency Remove patient dependence on botulinum toxin treatment Laryngeal-Specific Risks Decreased vocal range, especially loss of higher range Poor vocal quality Weak or breathy voice Breathing problems Swallowing problems Sensation of increased 'phlegm' in throat Recurrence of symptoms of AdSD Development of additional dystonia in larynx, throat, or elsewhere in the vocal tract (a product of the disease and not treatment) General Surgical Risks Bleeding Infection Seroma or Hematoma Scar Pain Anesthesia associated complications Heart Attack Stroke Death With respect to larynx specific risks, significant problems have rarely occurred. There have been a few patients that have had poor vocal outcome with profoundly weak voices. It may be possible to address these undesired outcomes with another surgical procedure or voice therapy. Some patients have reported some loss of vocal range, especially with higher pitched sounds. Some patients have reported minor vocal weakness or breathiness. Most patients with these issues state that it is insignificant and desire no further therapy. Options for treatment would include additional operative procedures or voice therapy. The majority of patients have self-reported a normal or near-normal voice after the procedure. Only a very few patients have had recurrence of AdSD symptoms. If spasms recur, options for further treatment include returning to botulinum toxin injections, further surgery, or possibly voice therapy. There have been no long-term breathing or swallowing problems. All patients that undergo the procedure do have a temporary problem with swallowing that can last a few weeks to a few months. Some patients complain of increased phlegm production, or the sensation of increased phlegm production and this may represent residue of a minor swallowing problem. With respect to major surgical risks, there have been no major morbidities associated with this procedure, that is, no operative associated deaths, strokes, heart attacks, or otherwise. As an elective procedure, it is performed on reasonably healthy patients with minimal risk of undergoing general anesthesia.