Bipolar radiofrequency-induced thermotherapy (rfitt) for the treatment of spasmodic dysphonia. A report of three cases

Abstract

The symptoms of adductor spasmodic dysphonia are most commonly palliated by periodic botulinum toxin injections. The need for repeated injections, difficulty in obtaining injections and cost make this form of treatment intolerable for some patients. To address these concerns, we propose a new treatment approach utilizing trans-oral recurrent nerve coagulation. The goal is to weaken the force of laryngeal closure during spasms by creating fibrosis of the terminal branches of one recurrent nerve through coagulation. Under general anesthesia without paralysis, an electrical stimulator is used to identify the region within the thyroarytenoid muscle that produces the greatest contraction with minimal stimulation. The radiofrequency laryngeal probe or electrocautery device is introduced into this position, and energy is delivered. The location of the region of maximal stimulation is usually just lateral and anterior to the vocal process of the arytenoids. Between 1989 and 2000, seven patients were treated with electrocautery. To achieve remission of spasms, three patients needed three sessions, four needed two sessions and one only one session. Since 2001, three patients have achieved remission of spasms with a single treatment with radiofrequency during which 80 J was delivered. Voice results are comparable to those obtained with botulinum toxin. Initially, the voice is breathy and laryngeal examination shows complete vocal fold immobility. After 1-2 months, the voice improves and examination reveals unilateral hypomobility. Trans-oral recurrent nerve coagulation is an effective alternative to botulinum toxin injections.